Graphical User Interfaces for Volume Rendering Applications in Medical Imaging

OpenAIRE

Lindfors, Lisa; Lindmark, Hanna

2002-01-01

Volume rendering applications are used in medical imaging in order to facilitate the analysis of three-dimensional image data. This study focuses on how to improve the usability of graphical user interfaces of these systems, by gathering user requirements. This is achieved by evaluations of existing systems, together with interviews and observations at clinics in Sweden that use volume rendering to some extent. The usability of the applications of today is not sufficient, according to the use...

Mucosal detail at CT virtual reality: surface versus volume rendering.

Science.gov (United States)

Hopper, K D; Iyriboz, A T; Wise, S W; Neuman, J D; Mauger, D T; Kasales, C J

2000-02-01

To evaluate computed tomographic virtual reality with volumetric versus surface rendering. Virtual reality images were reconstructed for 27 normal or pathologic colonic, gastric, or bronchial structures in four ways: the transition zone (a) reconstructed separately from the wall by using volume rendering; (b) with attenuation equal to air; (c) with attenuation equal to wall (soft tissue); (d) with attenuation halfway between air and wall. The four reconstructed images were randomized. Four experienced imagers blinded to the reconstruction graded them from best to worst with predetermined criteria. All readers rated images with the transition zone as a separate structure as overwhelmingly superior (P Virtual reality is best with volume rendering, with the transition zone (mucosa) between the wall and air reconstructed as a separate structure.

On the design of a real-time volume rendering engine

NARCIS (Netherlands)

Smit, Jaap; Wessels, H.L.F.; van der Horst, A.; Bentum, Marinus Jan

1992-01-01

An architecture for a Real-Time Volume Rendering Engine (RT-VRE) is given, capable of computing 750 × 750 × 512 samples from a 3D dataset at a rate of 25 images per second. The RT-VRE uses for this purpose 64 dedicated rendering chips, cooperating with 16 RISC-processors. A plane interpolator

On the design of a real-time volume rendering engine

NARCIS (Netherlands)

Smit, Jaap; Wessels, H.J.; van der Horst, A.; Bentum, Marinus Jan

1995-01-01

An architecture for a Real-Time Volume Rendering Engine (RT-VRE) is given, capable of computing 750 × 750 × 512 samples from a 3D dataset at a rate of 25 images per second. The RT-VRE uses for this purpose 64 dedicated rendering chips, cooperating with 16 RISC-processors. A plane interpolator

A cache-friendly sampling strategy for texture-based volume rendering on GPU

Directory of Open Access Journals (Sweden)

Junpeng Wang

2017-06-01

Full Text Available The texture-based volume rendering is a memory-intensive algorithm. Its performance relies heavily on the performance of the texture cache. However, most existing texture-based volume rendering methods blindly map computational resources to texture memory and result in incoherent memory access patterns, causing low cache hit rates in certain cases. The distance between samples taken by threads of an atomic scheduling unit (e.g. a warp of 32 threads in CUDA of the GPU is a crucial factor that affects the texture cache performance. Based on this fact, we present a new sampling strategy, called Warp Marching, for the ray-casting algorithm of texture-based volume rendering. The effects of different sample organizations and different thread-pixel mappings in the ray-casting algorithm are thoroughly analyzed. Also, a pipeline manner color blending approach is introduced and the power of warp-level GPU operations is leveraged to improve the efficiency of parallel executions on the GPU. In addition, the rendering performance of the Warp Marching is view-independent, and it outperforms existing empty space skipping techniques in scenarios that need to render large dynamic volumes in a low resolution image. Through a series of micro-benchmarking and real-life data experiments, we rigorously analyze our sampling strategies and demonstrate significant performance enhancements over existing sampling methods.

Frequency Analysis of Gradient Estimators in Volume Rendering

NARCIS (Netherlands)

Bentum, Marinus Jan; Lichtenbelt, Barthold B.A.; Malzbender, Tom

1996-01-01

Gradient information is used in volume rendering to classify and color samples along a ray. In this paper, we present an analysis of the theoretically ideal gradient estimator and compare it to some commonly used gradient estimators. A new method is presented to calculate the gradient at arbitrary

Real-time 3-dimensional fetal echocardiography with an instantaneous volume-rendered display: early description and pictorial essay.

Science.gov (United States)

Sklansky, Mark S; DeVore, Greggory R; Wong, Pierre C

2004-02-01

Random fetal motion, rapid fetal heart rates, and cumbersome processing algorithms have limited reconstructive approaches to 3-dimensional fetal cardiac imaging. Given the recent development of real-time, instantaneous volume-rendered sonographic displays of volume data, we sought to apply this technology to fetal cardiac imaging. We obtained 1 to 6 volume data sets on each of 30 fetal hearts referred for formal fetal echocardiography. Each volume data set was acquired over 2 to 8 seconds and stored on the system's hard drive. Rendered images were subsequently processed to optimize translucency, smoothing, and orientation and cropped to reveal "surgeon's eye views" of clinically relevant anatomic structures. Qualitative comparison was made with conventional fetal echocardiography for each subject. Volume-rendered displays identified all major abnormalities but failed to identify small ventricular septal defects in 2 patients. Important planes and views not visualized during the actual scans were generated with minimal processing of rendered image displays. Volume-rendered displays tended to have slightly inferior image quality compared with conventional 2-dimensional images. Real-time 3-dimensional echocardiography with instantaneous volume-rendered displays of the fetal heart represents a new approach to fetal cardiac imaging with tremendous clinical potential.

Immersive volume rendering of blood vessels

Science.gov (United States)

Long, Gregory; Kim, Han Suk; Marsden, Alison; Bazilevs, Yuri; Schulze, Jürgen P.

2012-03-01

In this paper, we present a novel method of visualizing flow in blood vessels. Our approach reads unstructured tetrahedral data, resamples it, and uses slice based 3D texture volume rendering. Due to the sparse structure of blood vessels, we utilize an octree to efficiently store the resampled data by discarding empty regions of the volume. We use animation to convey time series data, wireframe surface to give structure, and utilize the StarCAVE, a 3D virtual reality environment, to add a fully immersive element to the visualization. Our tool has great value in interdisciplinary work, helping scientists collaborate with clinicians, by improving the understanding of blood flow simulations. Full immersion in the flow field allows for a more intuitive understanding of the flow phenomena, and can be a great help to medical experts for treatment planning.

View compensated compression of volume rendered images for remote visualization.

Science.gov (United States)

Lalgudi, Hariharan G; Marcellin, Michael W; Bilgin, Ali; Oh, Han; Nadar, Mariappan S

2009-07-01

Remote visualization of volumetric images has gained importance over the past few years in medical and industrial applications. Volume visualization is a computationally intensive process, often requiring hardware acceleration to achieve a real time viewing experience. One remote visualization model that can accomplish this would transmit rendered images from a server, based on viewpoint requests from a client. For constrained server-client bandwidth, an efficient compression scheme is vital for transmitting high quality rendered images. In this paper, we present a new view compensation scheme that utilizes the geometric relationship between viewpoints to exploit the correlation between successive rendered images. The proposed method obviates motion estimation between rendered images, enabling significant reduction to the complexity of a compressor. Additionally, the view compensation scheme, in conjunction with JPEG2000 performs better than AVC, the state of the art video compression standard.

A concept of volume rendering guided search process to analyze medical data set.

Science.gov (United States)

Zhou, Jianlong; Xiao, Chun; Wang, Zhiyan; Takatsuka, Masahiro

2008-03-01

This paper firstly presents an approach of parallel coordinates based parameter control panel (PCP). The PCP is used to control parameters of focal region-based volume rendering (FRVR) during data analysis. It uses a parallel coordinates style interface. Different rendering parameters represented with nodes on each axis, and renditions based on related parameters are connected using polylines to show dependencies between renditions and parameters. Based on the PCP, a concept of volume rendering guided search process is proposed. The search pipeline is divided into four phases. Different parameters of FRVR are recorded and modulated in the PCP during search phases. The concept shows that volume visualization could play the role of guiding a search process in the rendition space to help users to efficiently find local structures of interest. The usability of the proposed approach is evaluated to show its effectiveness.

TransCut: interactive rendering of translucent cutouts.

Science.gov (United States)

Li, Dongping; Sun, Xin; Ren, Zhong; Lin, Stephen; Tong, Yiying; Guo, Baining; Zhou, Kun

2013-03-01

We present TransCut, a technique for interactive rendering of translucent objects undergoing fracturing and cutting operations. As the object is fractured or cut open, the user can directly examine and intuitively understand the complex translucent interior, as well as edit material properties through painting on cross sections and recombining the broken pieces—all with immediate and realistic visual feedback. This new mode of interaction with translucent volumes is made possible with two technical contributions. The first is a novel solver for the diffusion equation (DE) over a tetrahedral mesh that produces high-quality results comparable to the state-of-art finite element method (FEM) of Arbree et al. but at substantially higher speeds. This accuracy and efficiency is obtained by computing the discrete divergences of the diffusion equation and constructing the DE matrix using analytic formulas derived for linear finite elements. The second contribution is a multiresolution algorithm to significantly accelerate our DE solver while adapting to the frequent changes in topological structure of dynamic objects. The entire multiresolution DE solver is highly parallel and easily implemented on the GPU. We believe TransCut provides a novel visual effect for heterogeneous translucent objects undergoing fracturing and cutting operations.

Use of volume-rendered images in registration of nuclear medicine studies

International Nuclear Information System (INIS)

Wallis, J.W.; Miller, T.R.; Hsu, S.S.

1995-01-01

A simple operator-guided alignment technique based on volume-rendered images was developed to register tomographic nuclear medicine studies. For each of 2 three-dimensional data sets to be registered, volume-rendered images were generated in 3 orthogonal projections (x,y,z) using the method of maximum-activity projection. Registration was achieved as follows: (a) One of the rendering orientations (e.g. x) was chosen for manipulation; (b) The two dimensional rendering was translated and rotated under operator control to achieve the best alignment as determined by visual assessment; (c) This rotation and translation was then applied to the underlying three-dimensional data set, with updating of the rendered images in each of the orthogonal projections; (d) Another orientation was chosen, and the process repeated. Since manipulation was performed on the small two-dimensional rendered image, feedback was instantaneous. To aid in the visual alignment, difference images and flicker images (toggling between the two data sets) were displayed. Accuracy was assessed by analysis of separate clinical data sets acquired without patient movement. After arbitrary rotation and translation of one of the two data sets, the 2 data sets were registered. Mean registration error was 0.36 pixels, corresponding to a 2.44 mm registration error. Thus, accurate registration can be achieved in under 10 minutes using this simple technique. The accuracy of registration was assessed with use of duplicate SPECT studies originating from separate reconstructions of the data from each of the detectors of a triple-head gamma camera

Lighting design for globally illuminated volume rendering.

Science.gov (United States)

Zhang, Yubo; Ma, Kwan-Liu

2013-12-01

With the evolution of graphics hardware, high quality global illumination becomes available for real-time volume rendering. Compared to local illumination, global illumination can produce realistic shading effects which are closer to real world scenes, and has proven useful for enhancing volume data visualization to enable better depth and shape perception. However, setting up optimal lighting could be a nontrivial task for average users. There were lighting design works for volume visualization but they did not consider global light transportation. In this paper, we present a lighting design method for volume visualization employing global illumination. The resulting system takes into account view and transfer-function dependent content of the volume data to automatically generate an optimized three-point lighting environment. Our method fully exploits the back light which is not used by previous volume visualization systems. By also including global shadow and multiple scattering, our lighting system can effectively enhance the depth and shape perception of volumetric features of interest. In addition, we propose an automatic tone mapping operator which recovers visual details from overexposed areas while maintaining sufficient contrast in the dark areas. We show that our method is effective for visualizing volume datasets with complex structures. The structural information is more clearly and correctly presented under the automatically generated light sources.

Morphological pyramids in multiresolution MIP rendering of large volume data : Survey and new results

NARCIS (Netherlands)

Roerdink, J.B.T.M.

We survey and extend nonlinear signal decompositions based on morphological pyramids, and their application to multiresolution maximum intensity projection (MIP) volume rendering with progressive refinement and perfect reconstruction. The structure of the resulting multiresolution rendering

State of the Art in Transfer Functions for Direct Volume Rendering

KAUST Repository

Ljung, Patric; Krü ger, Jens; Groller, Eduard; Hadwiger, Markus; Hansen, Charles D.; Ynnerman, Anders

2016-01-01

A central topic in scientific visualization is the transfer function (TF) for volume rendering. The TF serves a fundamental role in translating scalar and multivariate data into color and opacity to express and reveal the relevant features present in the data studied. Beyond this core functionality, TFs also serve as a tool for encoding and utilizing domain knowledge and as an expression for visual design of material appearances. TFs also enable interactive volumetric exploration of complex data. The purpose of this state-of-the-art report (STAR) is to provide an overview of research into the various aspects of TFs, which lead to interpretation of the underlying data through the use of meaningful visual representations. The STAR classifies TF research into the following aspects: dimensionality, derived attributes, aggregated attributes, rendering aspects, automation, and user interfaces. The STAR concludes with some interesting research challenges that form the basis of an agenda for the development of next generation TF tools and methodologies. © 2016 The Author(s) Computer Graphics Forum © 2016 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

State of the Art in Transfer Functions for Direct Volume Rendering

KAUST Repository

Ljung, Patric

2016-07-04

A central topic in scientific visualization is the transfer function (TF) for volume rendering. The TF serves a fundamental role in translating scalar and multivariate data into color and opacity to express and reveal the relevant features present in the data studied. Beyond this core functionality, TFs also serve as a tool for encoding and utilizing domain knowledge and as an expression for visual design of material appearances. TFs also enable interactive volumetric exploration of complex data. The purpose of this state-of-the-art report (STAR) is to provide an overview of research into the various aspects of TFs, which lead to interpretation of the underlying data through the use of meaningful visual representations. The STAR classifies TF research into the following aspects: dimensionality, derived attributes, aggregated attributes, rendering aspects, automation, and user interfaces. The STAR concludes with some interesting research challenges that form the basis of an agenda for the development of next generation TF tools and methodologies. © 2016 The Author(s) Computer Graphics Forum © 2016 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

An Extension of Fourier-Wavelet Volume Rendering by View Interpolation

NARCIS (Netherlands)

Westenberg, Michel A.; Roerdink, Jos B.T.M.

2001-01-01

This paper describes an extension to Fourier-wavelet volume rendering (FWVR), which is a Fourier domain implementation of the wavelet X-ray transform. This transform combines integration along the line of sight with a simultaneous 2-D wavelet transform in the view plane perpendicular to this line.

Development of volume rendering module for real-time visualization system

International Nuclear Information System (INIS)

Otani, Takayuki; Muramatsu, Kazuhiro

2000-03-01

Volume rendering is a method to visualize the distribution of physical quantities in the three dimensional space from any viewpoint by tracing the ray direction on the ordinary two dimensional monitoring display. It enables to provide the interior information as well as the surfacial one by producing the translucent images. Therefore, it is regarded as a very useful means as well as an important one in the analysis of the computational results of the scientific calculations, although it has, unfortunately, disadvantage to need a large amount of computing time. This report describes algorithm and its performance of the volume rendering soft-ware which was developed as an important functional module in the real-time visualization system PATRAS. This module can directly visualize the computed results on BFC grid. Moreover, it has already realized the speed-up in some parts of the software by the use of a newly developed heuristic technique. This report includes the investigation on the speed-up of the software by parallel processing. (author)

A point-based rendering approach for real-time interaction on mobile devices

Institute of Scientific and Technical Information of China (English)

LIANG XiaoHui; ZHAO QinPing; HE ZhiYing; XIE Ke; LIU YuBo

2009-01-01

Mobile device is an Important interactive platform. Due to the limitation of computation, memory, display area and energy, how to realize the efficient and real-time interaction of 3D models based on mobile devices is an important research topic. Considering features of mobile devices, this paper adopts remote rendering mode and point models, and then, proposes a transmission and rendering approach that could interact in real time. First, improved simplification algorithm based on MLS and display resolution of mobile devices is proposed. Then, a hierarchy selection of point models and a QoS transmission control strategy are given based on interest area of operator, interest degree of object in the virtual environment and rendering error. They can save the energy consumption. Finally, the rendering and interaction of point models are completed on mobile devices. The experiments show that our method is efficient.

3-D volume rendering visualization for calculated distributions of diesel spray; Diesel funmu kyodo suchi keisan kekka no sanjigen volume rendering hyoji

Energy Technology Data Exchange (ETDEWEB)

Yoshizaki, T; Imanishi, H; Nishida, K; Yamashita, H; Hiroyasu, H; Kaneda, K [Hiroshima University, Hiroshima (Japan)

1997-10-01

Three dimensional visualization technique based on volume rendering method has been developed in order to translate calculated results of diesel combustion simulation into realistically spray and flame images. This paper presents an overview of diesel combustion model which has been developed at Hiroshima University, a description of the three dimensional visualization technique, and some examples of spray and flame image generated by this visualization technique. 8 refs., 8 figs., 1 tab.

Diagnostic Accuracy of the Volume Rendering Images of Multi-Detector CT for the Detection of Lumbar Transverse Process Fractures

Energy Technology Data Exchange (ETDEWEB)

Lee, Yun Hak; Chun, Tong Jin [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

2012-01-15

To compare the accuracy of three-dimensional computed tomographic (3D CT) volume rendering techniques with axial images of multi-detector row computed tomography to identify lumbar transverse process (LTP) fractures in trauma patients. We retrospectively evaluated 42 patients with back pain as a result of blunt trauma between January and June of 2010. Two radiologists examined the 3D CT volume rendering images independently. The confirmation of a LTP fracture was based on the consensus of the axial images by the two radiologists. The results of 3D CT volume rendering images were compared with the axial images and the diagnostic powers (sensitivity, specificity, and accuracy) were calculated. Seven of the 42 patients had twenty five lumbar transverse process fractures. The diagnostic power of the 3D CT volume rendering technique is as accurate as axial images. Reader 1, sensitivity 96%, specificity 100%, accuracy 99.9%; and Reader 2 sensitivity 100%, specificity 99.8%, accuracy 99.8%. The accordance of the two radiologists was 99.8%. 3D CT volume rendering images can alternate axial images to detect lumbar transverse process fractures with good image quality.

SparseLeap: Efficient Empty Space Skipping for Large-Scale Volume Rendering

KAUST Repository

Hadwiger, Markus; Al-Awami, Ali K.; Beyer, Johanna; Agus, Marco; Pfister, Hanspeter

2017-01-01

Recent advances in data acquisition produce volume data of very high resolution and large size, such as terabyte-sized microscopy volumes. These data often contain many fine and intricate structures, which pose huge challenges for volume rendering, and make it particularly important to efficiently skip empty space. This paper addresses two major challenges: (1) The complexity of large volumes containing fine structures often leads to highly fragmented space subdivisions that make empty regions hard to skip efficiently. (2) The classification of space into empty and non-empty regions changes frequently, because the user or the evaluation of an interactive query activate a different set of objects, which makes it unfeasible to pre-compute a well-adapted space subdivision. We describe the novel SparseLeap method for efficient empty space skipping in very large volumes, even around fine structures. The main performance characteristic of SparseLeap is that it moves the major cost of empty space skipping out of the ray-casting stage. We achieve this via a hybrid strategy that balances the computational load between determining empty ray segments in a rasterization (object-order) stage, and sampling non-empty volume data in the ray-casting (image-order) stage. Before ray-casting, we exploit the fast hardware rasterization of GPUs to create a ray segment list for each pixel, which identifies non-empty regions along the ray. The ray-casting stage then leaps over empty space without hierarchy traversal. Ray segment lists are created by rasterizing a set of fine-grained, view-independent bounding boxes. Frame coherence is exploited by re-using the same bounding boxes unless the set of active objects changes. We show that SparseLeap scales better to large, sparse data than standard octree empty space skipping.

SparseLeap: Efficient Empty Space Skipping for Large-Scale Volume Rendering

KAUST Repository

Hadwiger, Markus

2017-08-28

Recent advances in data acquisition produce volume data of very high resolution and large size, such as terabyte-sized microscopy volumes. These data often contain many fine and intricate structures, which pose huge challenges for volume rendering, and make it particularly important to efficiently skip empty space. This paper addresses two major challenges: (1) The complexity of large volumes containing fine structures often leads to highly fragmented space subdivisions that make empty regions hard to skip efficiently. (2) The classification of space into empty and non-empty regions changes frequently, because the user or the evaluation of an interactive query activate a different set of objects, which makes it unfeasible to pre-compute a well-adapted space subdivision. We describe the novel SparseLeap method for efficient empty space skipping in very large volumes, even around fine structures. The main performance characteristic of SparseLeap is that it moves the major cost of empty space skipping out of the ray-casting stage. We achieve this via a hybrid strategy that balances the computational load between determining empty ray segments in a rasterization (object-order) stage, and sampling non-empty volume data in the ray-casting (image-order) stage. Before ray-casting, we exploit the fast hardware rasterization of GPUs to create a ray segment list for each pixel, which identifies non-empty regions along the ray. The ray-casting stage then leaps over empty space without hierarchy traversal. Ray segment lists are created by rasterizing a set of fine-grained, view-independent bounding boxes. Frame coherence is exploited by re-using the same bounding boxes unless the set of active objects changes. We show that SparseLeap scales better to large, sparse data than standard octree empty space skipping.

Wobbled splatting-a fast perspective volume rendering method for simulation of x-ray images from CT

International Nuclear Information System (INIS)

Birkfellner, Wolfgang; Seemann, Rudolf; Figl, Michael; Hummel, Johann; Ede, Christopher; Homolka, Peter; Yang Xinhui; Niederer, Peter; Bergmann, Helmar

2005-01-01

3D/2D registration, the automatic assignment of a global rigid-body transformation matching the coordinate systems of patient and preoperative volume scan using projection images, is an important topic in image-guided therapy and radiation oncology. A crucial part of most 3D/2D registration algorithms is the fast computation of digitally rendered radiographs (DRRs) to be compared iteratively to radiographs or portal images. Since registration is an iterative process, fast generation of DRRs-which are perspective summed voxel renderings-is desired. In this note, we present a simple and rapid method for generation of DRRs based on splat rendering. As opposed to conventional splatting, antialiasing of the resulting images is not achieved by means of computing a discrete point spread function (a so-called footprint), but by stochastic distortion of either the voxel positions in the volume scan or by the simulation of a focal spot of the x-ray tube with non-zero diameter. Our method generates slightly blurred DRRs suitable for registration purposes at framerates of approximately 10 Hz when rendering volume images with a size of 30 MB. (note)

Clustered deep shadow maps for integrated polyhedral and volume rendering

KAUST Repository

Bornik, Alexander

2012-01-01

This paper presents a hardware-accelerated approach for shadow computation in scenes containing both complex volumetric objects and polyhedral models. Our system is the first hardware accelerated complete implementation of deep shadow maps, which unifies the computation of volumetric and geometric shadows. Up to now such unified computation was limited to software-only rendering . Previous hardware accelerated techniques can handle only geometric or only volumetric scenes - both resulting in the loss of important properties of the original concept. Our approach supports interactive rendering of polyhedrally bounded volumetric objects on the GPU based on ray casting. The ray casting can be conveniently used for both the shadow map computation and the rendering. We show how anti-aliased high-quality shadows are feasible in scenes composed of multiple overlapping translucent objects, and how sparse scenes can be handled efficiently using clustered deep shadow maps. © 2012 Springer-Verlag.

Volume Visualization and Compositing on Large-Scale Displays Using Handheld Touchscreen Interaction

KAUST Repository

Gastelum, Cristhopper Jacobo Armenta

2011-07-27

Advances in the physical sciences have progressively delivered ever increasing, already extremely large data sets to be analyzed. High performance volume rendering has become critical to the scientists for a better understanding of the massive amounts of data to be visualized. Cluster based rendering systems have become the base line to achieve the power and flexibility required to perform such task. Furthermore, display arrays have become the most suitable solution to display these data sets at their natural size and resolution which can be critical for human perception and evaluation. The work in this thesis aims at improving the scalability and usability of volume rendering systems that target visualization on display arrays. The first part deals with improving the performance by introducing the implementations of two parallel compositing algorithms for volume rendering: direct send and binary swap. The High quality Volume Rendering (HVR) framework has been extended to accommodate parallel compositing where previously only serial compositing was possible. The preliminary results show improvements in the compositing times for direct send even for a small number of processors. Unfortunately, the results of binary swap exhibit a negative behavior. This is due to the naive use of the graphics hardware blending mechanism. The expensive transfers account for the lengthy compositing times. The second part targets the development of scalable and intuitive interaction mechanisms. It introduces the development of a new client application for multitouch tablet devices, like the Apple iPad. The main goal is to provide the HVR framework, that has been extended to use tiled displays, a more intuitive and portable interaction mechanism that can get advantage of the new environment. The previous client is a PC application for the typical desktop settings that use a mouse and keyboard as sources of interaction. The current implementation of the client lets the user steer and

Visualization of normal and abnormal inner ear with volume rendering technique using multislice spiral CT

International Nuclear Information System (INIS)

Ma Hui; Han Ping; Liang Bo; Lei Ziqiao; Liu Fang; Tian Zhiliang

2006-01-01

Objective: To evaluate the ability of the volume rendering technique to display the normal and abnormal inner ear structures. Methods: Forty normal earand 61 abnormal inner ears (40 congenital inner ear malformations, 7 labyrinthitis ossificans, and 14 inner ear erosion caused by cholesteatomas) were examined with a MSCT scanner. Axial imaging were performed using the following parameters: 120 kV, 100 mAs, 0.75 mm slice thickness, a pitch factor of 1. The axial images of interested ears were reconstructed with 0.1 mm reconstruction increment and a FOV of 50 mm. The 3D reconstructions were done with volume rendering technique on the workstation. Results: In the subjects without ear disorders a high quality 3D visualization of the inner ear could be achieved. In the patients with inner ear' disorders all inner ear malformations could be clearly displayed on 3D images as follows: (1) Michel deformity (one ear): There was complete absence of all cochlear and vestibular structures. (2) common cavity deformity (3 ears): The cochlea and vestibule were represented by a cystic cavity and couldn't be differentiated from each other. (3)incomplete partition type I (3 ears): The cochlea lacked the entire modiolus and cribriform area, resulting in a cystic appearance. (4) incomplete partition type II (Mondini deformity) (5 ears): The cochlea consisted of 1.5 turns, in which the middle and apical turns coalesced to form a cystic apex. (5) vestibular and semicircular canal malformations (14 ears): Cochlea was normal, vestibule dilated, semicircular canals were absent, hypoplastic or enlarged. (6) dilated vestibular aqueduct (14 ears): The vestibular aqueduct was bell-mouthed. In 7 patients with labyrinthifis ossificans, 3D images failed to clearly show the completeinner ears in 4 ears because of too high ossifications in the membranous labyrinth. In the other 3 ears volume rendering could display the thin cochlea basal turn and the intermittent semicircular canals. In the patients

Method and system for rendering and interacting with an adaptable computing environment

Science.gov (United States)

Osbourn, Gordon Cecil [Albuquerque, NM; Bouchard, Ann Marie [Albuquerque, NM

2012-06-12

An adaptable computing environment is implemented with software entities termed "s-machines", which self-assemble into hierarchical data structures capable of rendering and interacting with the computing environment. A hierarchical data structure includes a first hierarchical s-machine bound to a second hierarchical s-machine. The first hierarchical s-machine is associated with a first layer of a rendering region on a display screen and the second hierarchical s-machine is associated with a second layer of the rendering region overlaying at least a portion of the first layer. A screen element s-machine is linked to the first hierarchical s-machine. The screen element s-machine manages data associated with a screen element rendered to the display screen within the rendering region at the first layer.

Feed-forward volume rendering algorithm for moderately parallel MIMD machines

Science.gov (United States)

Yagel, Roni

1993-01-01

Algorithms for direct volume rendering on parallel and vector processors are investigated. Volumes are transformed efficiently on parallel processors by dividing the data into slices and beams of voxels. Equal sized sets of slices along one axis are distributed to processors. Parallelism is achieved at two levels. Because each slice can be transformed independently of others, processors transform their assigned slices with no communication, thus providing maximum possible parallelism at the first level. Within each slice, consecutive beams are incrementally transformed using coherency in the transformation computation. Also, coherency across slices can be exploited to further enhance performance. This coherency yields the second level of parallelism through the use of the vector processing or pipelining. Other ongoing efforts include investigations into image reconstruction techniques, load balancing strategies, and improving performance.

FluoRender: joint freehand segmentation and visualization for many-channel fluorescence data analysis.

Science.gov (United States)

Wan, Yong; Otsuna, Hideo; Holman, Holly A; Bagley, Brig; Ito, Masayoshi; Lewis, A Kelsey; Colasanto, Mary; Kardon, Gabrielle; Ito, Kei; Hansen, Charles

2017-05-26

Image segmentation and registration techniques have enabled biologists to place large amounts of volume data from fluorescence microscopy, morphed three-dimensionally, onto a common spatial frame. Existing tools built on volume visualization pipelines for single channel or red-green-blue (RGB) channels have become inadequate for the new challenges of fluorescence microscopy. For a three-dimensional atlas of the insect nervous system, hundreds of volume channels are rendered simultaneously, whereas fluorescence intensity values from each channel need to be preserved for versatile adjustment and analysis. Although several existing tools have incorporated support of multichannel data using various strategies, the lack of a flexible design has made true many-channel visualization and analysis unavailable. The most common practice for many-channel volume data presentation is still converting and rendering pseudosurfaces, which are inaccurate for both qualitative and quantitative evaluations. Here, we present an alternative design strategy that accommodates the visualization and analysis of about 100 volume channels, each of which can be interactively adjusted, selected, and segmented using freehand tools. Our multichannel visualization includes a multilevel streaming pipeline plus a triple-buffer compositing technique. Our method also preserves original fluorescence intensity values on graphics hardware, a crucial feature that allows graphics-processing-unit (GPU)-based processing for interactive data analysis, such as freehand segmentation. We have implemented the design strategies as a thorough restructuring of our original tool, FluoRender. The redesign of FluoRender not only maintains the existing multichannel capabilities for a greatly extended number of volume channels, but also enables new analysis functions for many-channel data from emerging biomedical-imaging techniques.

Usefulness of PC based 3D volume rendering technique in the evaluation of suspected aneurysm on brain MRA

International Nuclear Information System (INIS)

Baek, Seung Il; Lee, Ghi Jai; Shim, Jae Chan; Bang, Sun Woo; Ryu, Seok Jong; Kim, Ho Kyun

2002-01-01

To evaluated usefulness of volume rending technique using 3D visualization software on PC in patients with suspected intracranial aneurysm on brain MRA. We analyzed prospectively 21 patients with suspected aneurysms on the routine MIP images which were obtained 15 .deg. C increment along axial and sagittal plane, among 135 patients in whom brain MRA was done due to stroke symptoms for recent 5 months. The locations were the anterior communicating artery (A-com) in 8 patients, the posterior communicating artery (P-com) in 3, the ICA bifurcation in 5, the MCA bifurcation in 4, and the basilar tip in one. Male to female ratio was 14:7 and mean age was 62 years. MRA source images were sent to PC through LAN, and the existence of aneurysm was evaluated with volume rendering technique using 3D visualization software on PC. The presence or absence of aneurysm on MIP and volume rendering images was decided by the consensus of two radiologists. We found the aneurysms with volume rendering technique, from 1 patient among 8 patients with suspected aneurysm at A-com and also 1 patient among 3 patients with suspected aneurysm at P=com on routine MIP images. Confirmative angiography and interventional procedures were done in these 2 patients. The causes for mimicking the aneurysm on MIP were flow displacement artifact in 9, normal P-com infundibulum in 2, and overlapped or narrowed vessels in 8 patients, and among them confirmative angiography was done in 2 patient. Volume rendering technique using visualization software on PC is useful to scrutinize the suspected aneurysm on routine MIP images and to avoid further invasive angiography

Advantages and disadvantages of 3D ultrasound of thyroid nodules including thin slice volume rendering

Directory of Open Access Journals (Sweden)

Slapa Rafal

2011-01-01

Full Text Available Abstract Background The purpose of this study was to assess the advantages and disadvantages of 3D gray-scale and power Doppler ultrasound, including thin slice volume rendering (TSVR, applied for evaluation of thyroid nodules. Methods The retrospective evaluation by two observers of volumes of 71 thyroid nodules (55 benign, 16 cancers was performed using a new TSVR technique. Dedicated 4D ultrasound scanner with an automatic 6-12 MHz 4D probe was used. Statistical analysis was performed with Stata v. 8.2. Results Multiple logistic regression analysis demonstrated that independent risk factors of thyroid cancers identified by 3D ultrasound include: (a ill-defined borders of the nodule on MPR presentation, (b a lobulated shape of the nodule in the c-plane and (c a density of central vessels in the nodule within the minimal or maximal ranges. Combination of features provided sensitivity 100% and specificity 60-69% for thyroid cancer. Calcification/microcalcification-like echogenic foci on 3D ultrasound proved not to be a risk factor of thyroid cancer. Storage of the 3D data of the whole nodules enabled subsequent evaluation of new parameters and with new rendering algorithms. Conclusions Our results indicate that 3D ultrasound is a practical and reproducible method for the evaluation of thyroid nodules. 3D ultrasound stores volumes comprising the whole lesion or organ. Future detailed evaluations of the data are possible, looking for features that were not fully appreciated at the time of collection or applying new algorithms for volume rendering in order to gain important information. Three-dimensional ultrasound data could be included in thyroid cancer databases. Further multicenter large scale studies are warranted.

Clinical application of three-dimensional spiral CT cerebral angiography with volume rendering

International Nuclear Information System (INIS)

Duan Shaoyin; Huang Xi'en; Kang Jianghe; Zhang Dantong; Lin Qingchi; Cai Guoxiang; Xu Meixin; Pang Ruilin

2002-01-01

Objective: To study the methodology and assess the clinical value of three-dimensional CT angiography (3D-CTA) with volume rendering (VR) in cerebral vessels. Methods: Sixty-two patients were examined by means of 3D-CTA with volume rendering. VR was used in the reconstruction of 3D images, and the demonstration of normal vessels and vascular lesions were particularly analyzed. At the same time, comparisons were made between the images of VR and SSD, MIP, and also between the diagnosis of VR-CTA and DSA or postoperative results. Results: In VR images, cerebral vessel routes and vessel cavities were showed clearly, while the relationship among vascular lesions, surrounding vessels, and neighboring structure was distinguished. 50 cases (80.6%) were found positive, 48 of which were correct and 2 were false-positive compared with DSA or postoperative results. The accurate rate of diagnosis was 96.0%. There was no obvious difference in showing the cerebral vessel among the images of VR, SSD and MIP (P > 0.25). Conclusion: Three-dimensional CT cerebral angiography with VR is a new noninvasive effective method. It can even partly replace the DSA. The 3D-images have the characteristics of showing the cerebral vascular cavity and overlapped vessels without cutting the skull

Real-time interactive three-dimensional display of CT and MR imaging volume data

International Nuclear Information System (INIS)

Yla-Jaaski, J.; Kubler, O.; Kikinis, R.

1987-01-01

Real-time reconstruction of surfaces from CT and MR imaging volume data is demonstrated using a new algorithm and implementation in a parallel computer system. The display algorithm accepts noncubic 16-bit voxels directly as input. Operations such as interpolation, classification by thresholding, depth coding, simple lighting effects, and removal of parts of the volume by clipping planes are all supported on-line. An eight-processor implementation of the algorithm renders surfaces from typical CT data sets in real time to allow interactive rotation of the volume

3D Volume Rendering and 3D Printing (Additive Manufacturing).

Science.gov (United States)

Katkar, Rujuta A; Taft, Robert M; Grant, Gerald T

2018-07-01

Three-dimensional (3D) volume-rendered images allow 3D insight into the anatomy, facilitating surgical treatment planning and teaching. 3D printing, additive manufacturing, and rapid prototyping techniques are being used with satisfactory accuracy, mostly for diagnosis and surgical planning, followed by direct manufacture of implantable devices. The major limitation is the time and money spent generating 3D objects. Printer type, material, and build thickness are known to influence the accuracy of printed models. In implant dentistry, the use of 3D-printed surgical guides is strongly recommended to facilitate planning and reduce risk of operative complications. Copyright © 2018 Elsevier Inc. All rights reserved.

Interactive Volume Rendering of Diffusion Tensor Data

Energy Technology Data Exchange (ETDEWEB)

Hlawitschka, Mario; Weber, Gunther; Anwander, Alfred; Carmichael, Owen; Hamann, Bernd; Scheuermann, Gerik

2007-03-30

As 3D volumetric images of the human body become an increasingly crucial source of information for the diagnosis and treatment of a broad variety of medical conditions, advanced techniques that allow clinicians to efficiently and clearly visualize volumetric images become increasingly important. Interaction has proven to be a key concept in analysis of medical images because static images of 3D data are prone to artifacts and misunderstanding of depth. Furthermore, fading out clinically irrelevant aspects of the image while preserving contextual anatomical landmarks helps medical doctors to focus on important parts of the images without becoming disoriented. Our goal was to develop a tool that unifies interactive manipulation and context preserving visualization of medical images with a special focus on diffusion tensor imaging (DTI) data. At each image voxel, DTI provides a 3 x 3 tensor whose entries represent the 3D statistical properties of water diffusion locally. Water motion that is preferential to specific spatial directions suggests structural organization of the underlying biological tissue; in particular, in the human brain, the naturally occuring diffusion of water in the axon portion of neurons is predominantly anisotropic along the longitudinal direction of the elongated, fiber-like axons [MMM+02]. This property has made DTI an emerging source of information about the structural integrity of axons and axonal connectivity between brain regions, both of which are thought to be disrupted in a broad range of medical disorders including multiple sclerosis, cerebrovascular disease, and autism [Mos02, FCI+01, JLH+99, BGKM+04, BJB+03].

Forensic 3D Visualization of CT Data Using Cinematic Volume Rendering: A Preliminary Study.

Science.gov (United States)

Ebert, Lars C; Schweitzer, Wolf; Gascho, Dominic; Ruder, Thomas D; Flach, Patricia M; Thali, Michael J; Ampanozi, Garyfalia

2017-02-01

The 3D volume-rendering technique (VRT) is commonly used in forensic radiology. Its main function is to explain medical findings to state attorneys, judges, or police representatives. New visualization algorithms permit the generation of almost photorealistic volume renderings of CT datasets. The objective of this study is to present and compare a variety of radiologic findings to illustrate the differences between and the advantages and limitations of the current VRT and the physically based cinematic rendering technique (CRT). Seventy volunteers were shown VRT and CRT reconstructions of 10 different cases. They were asked to mark the findings on the images and rate them in terms of realism and understandability. A total of 48 of the 70 questionnaires were returned and included in the analysis. On the basis of most of the findings presented, CRT appears to be equal or superior to VRT with respect to the realism and understandability of the visualized findings. Overall, in terms of realism, the difference between the techniques was statistically significant (p 0.05). CRT, which is similar to conventional VRT, is not primarily intended for diagnostic radiologic image analysis, and therefore it should be used primarily as a tool to deliver visual information in the form of radiologic image reports. Using CRT for forensic visualization might have advantages over using VRT if conveying a high degree of visual realism is of importance. Most of the shortcomings of CRT have to do with the software being an early prototype.

Volume-Rendered 3D Display Of MR Angiograms in the Diagnosis of Cerebral Arteriovenous Malformations

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, K.; Katase, S.; Hachiya, J. [Kyorin Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology; Shiokawa, Y. [Kyorin Univ. School of Medicine, Tokyo (Japan). Dept. of Neurosurgery

2003-11-01

Purpose: To determine whether application of a volume-rendered display of 3D time-of-flight (TOF) MR angiography could assist the diagnosis of cerebral arteriovenous malformations (AVMs). Material and Methods: Volume-rendered 3D images of postcontrast 3D time-of-flight MR angiography were compared with conventional angiograms in 12 patients. The correlation between the 3D images and the operative findings was also analyzed in 5 patients. Results: The 3D-displayed images showed all of the feeders and drainers in 10 and 9 patients, respectively. In all patients, the nidus was three-dimensionally visualized. In 3 patients with hematomas, the relationship between the hematoma and the AVM was well demonstrated. The 3D images corresponded well with the operative findings in the 5 patients. Conclusion: This method is of help in assessing the relationship between the components of an AVM as well as that between an AVM and an associated hematoma.

Volume-Rendered 3D Display Of MR Angiograms in the Diagnosis of Cerebral Arteriovenous Malformations

International Nuclear Information System (INIS)

Tsuchiya, K.; Katase, S.; Hachiya, J.; Shiokawa, Y.

2003-01-01

Purpose: To determine whether application of a volume-rendered display of 3D time-of-flight (TOF) MR angiography could assist the diagnosis of cerebral arteriovenous malformations (AVMs). Material and Methods: Volume-rendered 3D images of postcontrast 3D time-of-flight MR angiography were compared with conventional angiograms in 12 patients. The correlation between the 3D images and the operative findings was also analyzed in 5 patients. Results: The 3D-displayed images showed all of the feeders and drainers in 10 and 9 patients, respectively. In all patients, the nidus was three-dimensionally visualized. In 3 patients with hematomas, the relationship between the hematoma and the AVM was well demonstrated. The 3D images corresponded well with the operative findings in the 5 patients. Conclusion: This method is of help in assessing the relationship between the components of an AVM as well as that between an AVM and an associated hematoma

Evaluation of the relationship between extremity soft tissue sarcomas and adjacent major vessels using contrast-enhanced multidetector CT and three-dimensional volume-rendered CT angiography - A preliminary study

International Nuclear Information System (INIS)

Li, YangKang; Lin, JianBang; Cai, AiQun; Zhou, XiuGuo; Zheng, Yu; Wei, XiaoLong; Cheng, Ying; Liu, GuoRui

2013-01-01

Background: Accurate description of the relationship between extremity soft tissue sarcoma and the adjacent major vessels is crucial for successful surgery. In addition to magnetic resonance imaging (MRI) or in patients who cannot undergo MRI, two-dimensional (2D) postcontrast computed tomography (CT) images and three-dimensional (3D) volume-rendered CT angiography may be valuable alternative imaging techniques for preoperative evaluation of extremity sarcomas. Purpose: To preoperatively assess extremity sarcomas using multidetector CT (MDCT), with emphasis on postcontrast MDCT images and 3D volume-rendered MDCT angiography in evaluating the relationship between tumors and adjacent major vessels. Material and Methods: MDCT examinations were performed on 13 patients with non-metastatic extremity sarcomas. Conventional CT images and 3D volume-rendered CT angiography were evaluated, with focus on the relationship between tumors and adjacent major vessels. Kappa consistency statistics were performed with surgery serving as the reference standard. Results: The relationship between sarcomas and adjacent vessels was described as one of three patterns: proximity, adhesion, and encasement. Proximity was seen in five cases on postcontrast CT images or in eight cases on volume-rendered images. Adhesion was seen in three cases on both postcontrast CT images and volume-rendered images. Encasement was seen in five cases on postcontrast CT images or in two cases on volume-rendered images. Compared to surgical results, postcontrast CT images had 100% sensitivity, 83.3% specificity, 87.5% positive predictive value, 100% negative predictive value, and 92.3% accuracy in the detection of vascular invasion (κ = 0.843, P = 0.002). 3D volume-rendered CT angiography had 71.4% sensitivity, 100% specificity, 100% positive predictive value, 75% negative predictive value, and 84.6% accuracy in the detection of vascular invasion (κ = 0.698, P = 0.008). On volume-rendered images, all cases

Volume rendering based on magnetic resonance imaging: advances in understanding the three-dimensional anatomy of the human knee

Science.gov (United States)

Anastasi, Giuseppe; Bramanti, Placido; Di Bella, Paolo; Favaloro, Angelo; Trimarchi, Fabio; Magaudda, Ludovico; Gaeta, Michele; Scribano, Emanuele; Bruschetta, Daniele; Milardi, Demetrio

2007-01-01

The choice of medical imaging techniques, for the purpose of the present work aimed at studying the anatomy of the knee, derives from the increasing use of images in diagnostics, research and teaching, and the subsequent importance that these methods are gaining within the scientific community. Medical systems using virtual reality techniques also offer a good alternative to traditional methods, and are considered among the most important tools in the areas of research and teaching. In our work we have shown some possible uses of three-dimensional imaging for the study of the morphology of the normal human knee, and its clinical applications. We used the direct volume rendering technique, and created a data set of images and animations to allow us to visualize the single structures of the human knee in three dimensions. Direct volume rendering makes use of specific algorithms to transform conventional two-dimensional magnetic resonance imaging sets of slices into see-through volume data set images. It is a technique which does not require the construction of intermediate geometric representations, and has the advantage of allowing the visualization of a single image of the full data set, using semi-transparent mapping. Digital images of human structures, and in particular of the knee, offer important information about anatomical structures and their relationships, and are of great value in the planning of surgical procedures. On this basis we studied seven volunteers with an average age of 25 years, who underwent magnetic resonance imaging. After elaboration of the data through post-processing, we analysed the structure of the knee in detail. The aim of our investigation was the three-dimensional image, in order to comprehend better the interactions between anatomical structures. We believe that these results, applied to living subjects, widen the frontiers in the areas of teaching, diagnostics, therapy and scientific research. PMID:17645453

Video-based rendering

CERN Document Server

Magnor, Marcus A

2005-01-01

Driven by consumer-market applications that enjoy steadily increasing economic importance, graphics hardware and rendering algorithms are a central focus of computer graphics research. Video-based rendering is an approach that aims to overcome the current bottleneck in the time-consuming modeling process and has applications in areas such as computer games, special effects, and interactive TV. This book offers an in-depth introduction to video-based rendering, a rapidly developing new interdisciplinary topic employing techniques from computer graphics, computer vision, and telecommunication en

Role of volume rendered 3-D computed tomography in conservative management of trauma-related thoracic injuries.

LENUS (Irish Health Repository)

OʼLeary, Donal Peter

2012-09-01

Pneumatic nail guns are a tool used commonly in the construction industry and are widely available. Accidental injuries from nail guns are common, and several cases of suicide using a nail gun have been reported. Computed tomographic (CT) imaging, together with echocardiography, has been shown to be the gold standard for investigation of these cases. We present a case of a 55-year-old man who presented to the accident and emergency unit of a community hospital following an accidental pneumatic nail gun injury to his thorax. Volume-rendered CT of the thorax allowed an accurate assessment of the thoracic injuries sustained by this patient. As there was no evidence of any acute life-threatening injury, a sternotomy was avoided and the patient was observed closely until discharge. In conclusion, volume-rendered 3-dimensional CT can greatly help in the decision to avoid an unnecessary sternotomy in patients with a thoracic nail gun injury.

Large-Scale Multi-Resolution Representations for Accurate Interactive Image and Volume Operations

KAUST Repository

Sicat, Ronell B.

2015-11-25

The resolutions of acquired image and volume data are ever increasing. However, the resolutions of commodity display devices remain limited. This leads to an increasing gap between data and display resolutions. To bridge this gap, the standard approach is to employ output-sensitive operations on multi-resolution data representations. Output-sensitive operations facilitate interactive applications since their required computations are proportional only to the size of the data that is visible, i.e., the output, and not the full size of the input. Multi-resolution representations, such as image mipmaps, and volume octrees, are crucial in providing these operations direct access to any subset of the data at any resolution corresponding to the output. Despite its widespread use, this standard approach has some shortcomings in three important application areas, namely non-linear image operations, multi-resolution volume rendering, and large-scale image exploration. This dissertation presents new multi-resolution representations for large-scale images and volumes that address these shortcomings. Standard multi-resolution representations require low-pass pre-filtering for anti- aliasing. However, linear pre-filters do not commute with non-linear operations. This becomes problematic when applying non-linear operations directly to any coarse resolution levels in standard representations. Particularly, this leads to inaccurate output when applying non-linear image operations, e.g., color mapping and detail-aware filters, to multi-resolution images. Similarly, in multi-resolution volume rendering, this leads to inconsistency artifacts which manifest as erroneous differences in rendering outputs across resolution levels. To address these issues, we introduce the sparse pdf maps and sparse pdf volumes representations for large-scale images and volumes, respectively. These representations sparsely encode continuous probability density functions (pdfs) of multi-resolution pixel

Hybrid rendering of the chest and virtual bronchoscopy [corrected].

Science.gov (United States)

Seemann, M D; Seemann, O; Luboldt, W; Gebicke, K; Prime, G; Claussen, C D

2000-10-30

Thin-section spiral computed tomography was used to acquire the volume data sets of the thorax. The tracheobronchial system and pathological changes of the chest were visualized using a color-coded surface rendering method. The structures of interest were then superimposed on a volume rendering of the other thoracic structures, thus producing a hybrid rendering. The hybrid rendering technique exploit the advantages of both rendering methods and enable virtual bronchoscopic examinations using different representation models. Virtual bronchoscopic examinations with a transparent color-coded shaded-surface model enables the simultaneous visualization of both the airways and the adjacent structures behind of the tracheobronchial wall and therefore, offers a practical alternative to fiberoptic bronchoscopy. Hybrid rendering and virtual endoscopy obviate the need for time consuming detailed analysis and presentation of axial source images.

SPATIOTEMPORAL VISUALIZATION OF TIME-SERIES SATELLITE-DERIVED CO2 FLUX DATA USING VOLUME RENDERING AND GPU-BASED INTERPOLATION ON A CLOUD-DRIVEN DIGITAL EARTH

Directory of Open Access Journals (Sweden)

S. Wu

2017-10-01

Full Text Available The ocean carbon cycle has a significant influence on global climate, and is commonly evaluated using time-series satellite-derived CO2 flux data. Location-aware and globe-based visualization is an important technique for analyzing and presenting the evolution of climate change. To achieve realistic simulation of the spatiotemporal dynamics of ocean carbon, a cloud-driven digital earth platform is developed to support the interactive analysis and display of multi-geospatial data, and an original visualization method based on our digital earth is proposed to demonstrate the spatiotemporal variations of carbon sinks and sources using time-series satellite data. Specifically, a volume rendering technique using half-angle slicing and particle system is implemented to dynamically display the released or absorbed CO2 gas. To enable location-aware visualization within the virtual globe, we present a 3D particlemapping algorithm to render particle-slicing textures onto geospace. In addition, a GPU-based interpolation framework using CUDA during real-time rendering is designed to obtain smooth effects in both spatial and temporal dimensions. To demonstrate the capabilities of the proposed method, a series of satellite data is applied to simulate the air-sea carbon cycle in the China Sea. The results show that the suggested strategies provide realistic simulation effects and acceptable interactive performance on the digital earth.

Pulmonary nodules: sensitivity of maximum intensity projection versus that of volume rendering of 3D multidetector CT data

NARCIS (Netherlands)

Peloschek, Philipp; Sailer, Johannes; Weber, Michael; Herold, Christian J.; Prokop, Mathias; Schaefer-Prokop, Cornelia

2007-01-01

PURPOSE: To prospectively compare maximum intensity projection (MIP) and volume rendering (VR) of multidetector computed tomographic (CT) data for the detection of small intrapulmonary nodules. MATERIALS AND METHODS: This institutional review board-approved prospective study included 20 oncology

Time varying, multivariate volume data reduction

Energy Technology Data Exchange (ETDEWEB)

Ahrens, James P [Los Alamos National Laboratory; Fout, Nathaniel [UC DAVIS; Ma, Kwan - Liu [UC DAVIS

2010-01-01

Large-scale supercomputing is revolutionizing the way science is conducted. A growing challenge, however, is understanding the massive quantities of data produced by large-scale simulations. The data, typically time-varying, multivariate, and volumetric, can occupy from hundreds of gigabytes to several terabytes of storage space. Transferring and processing volume data of such sizes is prohibitively expensive and resource intensive. Although it may not be possible to entirely alleviate these problems, data compression should be considered as part of a viable solution, especially when the primary means of data analysis is volume rendering. In this paper we present our study of multivariate compression, which exploits correlations among related variables, for volume rendering. Two configurations for multidimensional compression based on vector quantization are examined. We emphasize quality reconstruction and interactive rendering, which leads us to a solution using graphics hardware to perform on-the-fly decompression during rendering. In this paper we present a solution which addresses the need for data reduction in large supercomputing environments where data resulting from simulations occupies tremendous amounts of storage. Our solution employs a lossy encoding scheme to acrueve data reduction with several options in terms of rate-distortion behavior. We focus on encoding of multiple variables together, with optional compression in space and time. The compressed volumes can be rendered directly with commodity graphics cards at interactive frame rates and rendering quality similar to that of static volume renderers. Compression results using a multivariate time-varying data set indicate that encoding multiple variables results in acceptable performance in the case of spatial and temporal encoding as compared to independent compression of variables. The relative performance of spatial vs. temporal compression is data dependent, although temporal compression has the

Freely-available, true-color volume rendering software and cryohistology data sets for virtual exploration of the temporal bone anatomy.

Science.gov (United States)

Kahrs, Lüder Alexander; Labadie, Robert Frederick

2013-01-01

Cadaveric dissection of temporal bone anatomy is not always possible or feasible in certain educational environments. Volume rendering using CT and/or MRI helps understanding spatial relationships, but they suffer in nonrealistic depictions especially regarding color of anatomical structures. Freely available, nonstained histological data sets and software which are able to render such data sets in realistic color could overcome this limitation and be a very effective teaching tool. With recent availability of specialized public-domain software, volume rendering of true-color, histological data sets is now possible. We present both feasibility as well as step-by-step instructions to allow processing of publicly available data sets (Visible Female Human and Visible Ear) into easily navigable 3-dimensional models using free software. Example renderings are shown to demonstrate the utility of these free methods in virtual exploration of the complex anatomy of the temporal bone. After exploring the data sets, the Visible Ear appears more natural than the Visible Human. We provide directions for an easy-to-use, open-source software in conjunction with freely available histological data sets. This work facilitates self-education of spatial relationships of anatomical structures inside the human temporal bone as well as it allows exploration of surgical approaches prior to cadaveric testing and/or clinical implementation. Copyright © 2013 S. Karger AG, Basel.

Three-dimensional spiral CT during arterial portography: comparison of three rendering techniques.

Science.gov (United States)

Heath, D G; Soyer, P A; Kuszyk, B S; Bliss, D F; Calhoun, P S; Bluemke, D A; Choti, M A; Fishman, E K

1995-07-01

The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

Three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT: applications and limitations

International Nuclear Information System (INIS)

Kim, Su Yeon; Choi, Sun Seob; Kang, Myung Jin; Shin, Tae Beom; Lee, Ki Nam; Kang, Myung Koo

2005-01-01

This study was conducted to know the applications and limitations of three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT. This study examined 25 patients who underwent temporal bone CT using a 16-row detector CT as a result of hearing problems or trauma. The axial CT scan of the temporal bone was performed with a 0.6 mm collimation, and a reconstruction was carried out with a U70u sharp of kernel value, a 1 mm thickness and 0.5-1.0 mm increments. After observing the ossicles in the axial and coronal images, virtual endoscopy was performed using a three dimensional volume rendering technique with a threshold value of-500 HU. The intra-operative otoendoscopy was performed in 12 ears, and was compared with the virtual endoscopy findings. Virtual endoscopy of the 29 ears without hearing problems demonstrated hypoplastic or an incomplete depiction of the stapes superstructures in 25 ears and a normal depiction in 4 ears. Virtual endoscopy of 21 ears with hearing problems demonstrated no ossicles in 1 ears, no malleus in 3 ears, a malleoincudal subluxation in 6 ears, a dysplastic incus in 5 ears, an incudostapedial subluxation in 9 ears, dysplastic stapes in 2 ears, a hypoplastic or incomplete depiction of the stapes in 16 ears and no stapes in 1 ears. In contrast to the intra-operative otoendoscopy, 8 out of 12 ears showed a hypoplastic or deformed stapes in the virtual endoscopy. Volume rendering virtual endoscopy using a multi-row detector CT is an excellent method for evaluation the ossicles in three dimension, even thought the partial volume effect for the stapes superstructures needs to be considered

Simulation and training of lumbar punctures using haptic volume rendering and a 6DOF haptic device

Science.gov (United States)

Färber, Matthias; Heller, Julika; Handels, Heinz

2007-03-01

The lumbar puncture is performed by inserting a needle into the spinal chord of the patient to inject medicaments or to extract liquor. The training of this procedure is usually done on the patient guided by experienced supervisors. A virtual reality lumbar puncture simulator has been developed in order to minimize the training costs and the patient's risk. We use a haptic device with six degrees of freedom (6DOF) to feedback forces that resist needle insertion and rotation. An improved haptic volume rendering approach is used to calculate the forces. This approach makes use of label data of relevant structures like skin, bone, muscles or fat and original CT data that contributes information about image structures that can not be segmented. A real-time 3D visualization with optional stereo view shows the punctured region. 2D visualizations of orthogonal slices enable a detailed impression of the anatomical context. The input data consisting of CT and label data and surface models of relevant structures is defined in an XML file together with haptic rendering and visualization parameters. In a first evaluation the visible human male data has been used to generate a virtual training body. Several users with different medical experience tested the lumbar puncture trainer. The simulator gives a good haptic and visual impression of the needle insertion and the haptic volume rendering technique enables the feeling of unsegmented structures. Especially, the restriction of transversal needle movement together with rotation constraints enabled by the 6DOF device facilitate a realistic puncture simulation.

MRI of the labyrinth with volume rendering for cochlear implants candidates

International Nuclear Information System (INIS)

Sakata, Motomichi; Harada, Kuniaki; Shirase, Ryuji; Suzuki, Junpei; Nagahama, Hiroshi

2009-01-01

We demonstrated three-dimensional models of the labyrinth by volume rendering (VR) in preoperative assessment for cochlear implantation. MRI data sets were acquired in selected subjects using three-dimensional-fast spin echo sequences (3D-FSE). We produced the three-dimensional models of the labyrinth from axial heavily T2-weighted images. The three-dimensional models distinguished the scala tympani and scala vestibuli and provided multidirectional images. The optimal threshold three-dimensional models clearly showed the focal region of signal loss in the cochlear turns (47.1%) and the presence of inner ear anomalies (17.3%) in our series of patients. This study was concluded that these three-dimensional models by VR provide the oto-surgeon with precise, detailed, and easily interpreted information about the cochlear turns for cochlear implants candidates. (author)

In Vivo CT Direct Volume Rendering: A Three-Dimensional Anatomical Description of the Heart

International Nuclear Information System (INIS)

Cutroneo, Giuseppina; Bruschetta, Daniele; Trimarchi, Fabio; Cacciola, Alberto; Cinquegrani, Maria; Duca, Antonio; Rizzo, Giuseppina; Alati, Emanuela; Gaeta, Michele; Milardi, Demetrio

2016-01-01

Since cardiac anatomy continues to play an important role in the practice of medicine and in the development of medical devices, the study of the heart in three dimensions is particularly useful to understand its real structure, function and proper location in the body. This study demonstrates a fine use of direct volume rendering, processing the data set images obtained by Computed Tomography (CT) of the heart of 5 subjects with age range between 18 and 42 years (2 male, 3 female), with no history of any overt cardiac disease. The cardiac structure in CT images was first extracted from the thorax by marking manually the regions of interest on the computer, and then it was stacked to create new volumetric data. The use of a specific algorithm allowed us to observe with a good perception of depth the heart and the skeleton of the thorax at the same time. Besides, in all examined subjects, it was possible to depict its structure and its position within the body and to study the integrity of papillary muscles, the fibrous tissue of cardiac valve and chordae tendineae and the course of coronary arteries. Our results demonstrated that one of the greatest advantages of algorithmic modifications of direct volume rendering parameters is that this method provides much necessary information in a single radiologic study. It implies a better accuracy in the study of the heart, being complementary to other diagnostic methods and facilitating the therapeutic plans

Use of multidetector row CT with volume renderings in right lobe living liver transplantation

International Nuclear Information System (INIS)

Ishifuro, Minoru; Akiyama, Yuji; Kushima, Toshio; Horiguchi, Jun; Nakashige, Aya; Tamura, Akihisa; Marukawa, Kazushi; Fukuda, Hiroshi; Ono, Chiaki; Ito, Katsuhide

2002-01-01

Multidetector row CT is a feasible diagnostic tool in pre- and postoperative liver partial transplantation. We can assess vascular anatomy and liver parenchyma as well as volumetry, which provide useful information for both donor selection and surgical planning. Disorders of the vascular and biliary systems are carefully observed in recipients. In addition, we evaluate liver regeneration of both the donor and the recipient by serial volumetry. We present how multidetector row CT with state-of-the-art three-dimensional volume renderings may be used in right lobe liver transplantation. (orig.)

Volume Ray Casting with Peak Finding and Differential Sampling

KAUST Repository

Knoll, A.

2009-11-01

Direct volume rendering and isosurfacing are ubiquitous rendering techniques in scientific visualization, commonly employed in imaging 3D data from simulation and scan sources. Conventionally, these methods have been treated as separate modalities, necessitating different sampling strategies and rendering algorithms. In reality, an isosurface is a special case of a transfer function, namely a Dirac impulse at a given isovalue. However, artifact-free rendering of discrete isosurfaces in a volume rendering framework is an elusive goal, requiring either infinite sampling or smoothing of the transfer function. While preintegration approaches solve the most obvious deficiencies in handling sharp transfer functions, artifacts can still result, limiting classification. In this paper, we introduce a method for rendering such features by explicitly solving for isovalues within the volume rendering integral. In addition, we present a sampling strategy inspired by ray differentials that automatically matches the frequency of the image plane, resulting in fewer artifacts near the eye and better overall performance. These techniques exhibit clear advantages over standard uniform ray casting with and without preintegration, and allow for high-quality interactive volume rendering with sharp C0 transfer functions. © 2009 IEEE.

Hardware-accelerated autostereogram rendering for interactive 3D visualization

Science.gov (United States)

Petz, Christoph; Goldluecke, Bastian; Magnor, Marcus

2003-05-01

Single Image Random Dot Stereograms (SIRDS) are an attractive way of depicting three-dimensional objects using conventional display technology. Once trained in decoupling the eyes' convergence and focusing, autostereograms of this kind are able to convey the three-dimensional impression of a scene. We present in this work an algorithm that generates SIRDS at interactive frame rates on a conventional PC. The presented system allows rotating a 3D geometry model and observing the object from arbitrary positions in real-time. Subjective tests show that the perception of a moving or rotating 3D scene presents no problem: The gaze remains focused onto the object. In contrast to conventional SIRDS algorithms, we render multiple pixels in a single step using a texture-based approach, exploiting the parallel-processing architecture of modern graphics hardware. A vertex program determines the parallax for each vertex of the geometry model, and the graphics hardware's texture unit is used to render the dot pattern. No data has to be transferred between main memory and the graphics card for generating the autostereograms, leaving CPU capacity available for other tasks. Frame rates of 25 fps are attained at a resolution of 1024x512 pixels on a standard PC using a consumer-grade nVidia GeForce4 graphics card, demonstrating the real-time capability of the system.

Mathematical models for volume rendering and neutron transport

International Nuclear Information System (INIS)

Max, N.

1994-09-01

This paper reviews several different models for light interaction with volume densities of absorbing, glowing, reflecting, or scattering material. They include absorption only, glow only, glow and absorption combined, single scattering of external illumination, and multiple scattering. The models are derived from differential equations, and illustrated on a data set representing a cloud. They are related to corresponding models in neutron transport. The multiple scattering model uses an efficient method to propagate the radiation which does not suffer from the ray effect

GenExp: an interactive web-based genomic DAS client with client-side data rendering.

Directory of Open Access Journals (Sweden)

Bernat Gel Moreno

Full Text Available BACKGROUND: The Distributed Annotation System (DAS offers a standard protocol for sharing and integrating annotations on biological sequences. There are more than 1000 DAS sources available and the number is steadily increasing. Clients are an essential part of the DAS system and integrate data from several independent sources in order to create a useful representation to the user. While web-based DAS clients exist, most of them do not have direct interaction capabilities such as dragging and zooming with the mouse. RESULTS: Here we present GenExp, a web based and fully interactive visual DAS client. GenExp is a genome oriented DAS client capable of creating informative representations of genomic data zooming out from base level to complete chromosomes. It proposes a novel approach to genomic data rendering and uses the latest HTML5 web technologies to create the data representation inside the client browser. Thanks to client-side rendering most position changes do not need a network request to the server and so responses to zooming and panning are almost immediate. In GenExp it is possible to explore the genome intuitively moving it with the mouse just like geographical map applications. Additionally, in GenExp it is possible to have more than one data viewer at the same time and to save the current state of the application to revisit it later on. CONCLUSIONS: GenExp is a new interactive web-based client for DAS and addresses some of the short-comings of the existing clients. It uses client-side data rendering techniques resulting in easier genome browsing and exploration. GenExp is open source under the GPL license and it is freely available at http://gralggen.lsi.upc.edu/recerca/genexp.

Fast DRR splat rendering using common consumer graphics hardware

International Nuclear Information System (INIS)

Spoerk, Jakob; Bergmann, Helmar; Wanschitz, Felix; Dong, Shuo; Birkfellner, Wolfgang

2007-01-01

Digitally rendered radiographs (DRR) are a vital part of various medical image processing applications such as 2D/3D registration for patient pose determination in image-guided radiotherapy procedures. This paper presents a technique to accelerate DRR creation by using conventional graphics hardware for the rendering process. DRR computation itself is done by an efficient volume rendering method named wobbled splatting. For programming the graphics hardware, NVIDIAs C for Graphics (Cg) is used. The description of an algorithm used for rendering DRRs on the graphics hardware is presented, together with a benchmark comparing this technique to a CPU-based wobbled splatting program. Results show a reduction of rendering time by about 70%-90% depending on the amount of data. For instance, rendering a volume of 2x10 6 voxels is feasible at an update rate of 38 Hz compared to 6 Hz on a common Intel-based PC using the graphics processing unit (GPU) of a conventional graphics adapter. In addition, wobbled splatting using graphics hardware for DRR computation provides higher resolution DRRs with comparable image quality due to special processing characteristics of the GPU. We conclude that DRR generation on common graphics hardware using the freely available Cg environment is a major step toward 2D/3D registration in clinical routine

Evaluation of obstructive airway lesions in complex congenital heart disease using composite volume-rendered images from multislice CT

International Nuclear Information System (INIS)

Choo, Ki Seok; Kim, Chang Won; Lee, Tae Hong; Kim, Suk; Kim, Kun Il; Lee, Hyoung Doo; Ban, Ji Eun; Sung, Si Chan; Chang, Yun Hee

2006-01-01

Multislice CT (MSCT) allows high-quality volume-rendered (VR) and composite volume-rendered images. To investigate the clinical usefulness of composite VR images in the evaluation of the relationship between cardiovascular structures and the airway in children with complex congenital heart disease (CHD). Four- or 16-slice MSCT scanning was performed consecutively in 77 children (mean age 6.4 months) with CHD and respiratory symptoms, a chest radiographic abnormality, or abnormal course of the pulmonary artery on ECHO. MSCT scanning was performed during breathing or after sedation. Contrast medium (2 ml/kg) was administered through a pedal venous route or arm vein in all patients. The VR technique was used to reconstruct the cardiovascular structures and airway, and then both VR images were composed using the commercial software (VoxelPlus 2 ; Daejeon, Korea). Stenoses were seen in the trachea in 1 patient and in the bronchi in 14 patients (19%). Other patients with complex CHD did not have significant airway stenoses. Composite VR images with MSCT can provide more exact airway images in relationship to the surrounding cardiovascular structures and thus help in optimizing management strategies in treating CHD. (orig.)

Enabling Real-Time Volume Rendering of Functional Magnetic Resonance Imaging on an iOS Device.

Science.gov (United States)

Holub, Joseph; Winer, Eliot

2017-12-01

Powerful non-invasive imaging technologies like computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI) are used daily by medical professionals to diagnose and treat patients. While 2D slice viewers have long been the standard, many tools allowing 3D representations of digital medical data are now available. The newest imaging advancement, functional MRI (fMRI) technology, has changed medical imaging from viewing static to dynamic physiology (4D) over time, particularly to study brain activity. Add this to the rapid adoption of mobile devices for everyday work and the need to visualize fMRI data on tablets or smartphones arises. However, there are few mobile tools available to visualize 3D MRI data, let alone 4D fMRI data. Building volume rendering tools on mobile devices to visualize 3D and 4D medical data is challenging given the limited computational power of the devices. This paper describes research that explored the feasibility of performing real-time 3D and 4D volume raycasting on a tablet device. The prototype application was tested on a 9.7" iPad Pro using two different fMRI datasets of brain activity. The results show that mobile raycasting is able to achieve between 20 and 40 frames per second for traditional 3D datasets, depending on the sampling interval, and up to 9 frames per second for 4D data. While the prototype application did not always achieve true real-time interaction, these results clearly demonstrated that visualizing 3D and 4D digital medical data is feasible with a properly constructed software framework.

Technical analysis of volume-rendering algorithms: application in low-contrast structures using liver vascularisation as a model; Analisi tecnica degli algoritmi di volume rendering: applicazione alle strutture a basso contrsto usando come modello la vascolarizzazione epatica

Energy Technology Data Exchange (ETDEWEB)

Cademartiri, Filippo [Erasmus Medical Center, Rotterdam (Netherlands); Luccichenti, Giacomo [Fondazione Biomedica Europea ONLUS, Roma (Italy); Runza, Giuseppe; Bartolotta, Tommaso Vincenzo; Midiri, Massimo [Palermo Univ., Palermo (Italy). Sezione di scienze radiologiche; Gualerzi, Massimo; Brambilla, Lorenzo; Coruzzi, Paolo [Parma Univ., Parma (Italy). UO di prevenzione e riabilitazione vascolare, Fondazione Don C. Gnocchi ONLUS; Soliani, Paolo; Sianesi, Mario [Parma Univ., Parma (Italy). Dipartimento di chirurgia

2005-04-01

Purpose: To assess the influence of pre-set volume rendering opacity curves (OC) on image quality and to identify which absolute parameters (density of aorta, hepatic parenchyma and portal vein) affect visualization of portal vascular structures (low-contrast structures). Materials and methods: Twenty-two patients underwent a dual-phase spiral CT with the following parameters: collimation 3 mm, pitch 2, increment 1 mm. Three scans were performed: one without contrast medium and the latter two after the injection of contrast material (conventionally identified as 'arterial' and 'portal'). The images were sent to a workstation running on an NT platform equipped with post-processing software allowing three-dimensional (3D) reconstructions to generate volume-rendered images of the vascular supply to the liver. Correlation between the absolute values of aorta, liver and portal vein density, OC parameters, and image quality were assessed. Results: 3D images generated using pre-set OC obtained a much mower overall quality score than those produced with OC set by the operator. High contrast between the liver and the portal vein, for example during the portal vascular phase, allows wider windows, thus improving image quality. Conversely, the OC in the parenchymal phase scans must have a high gradient in order to better differentiate between the vascular structures and the surrounding hepatic parenchyma. Conclusions: Image features considered to be of interest by the operator cannot be simplified by the mean of pre-set OC. Due to their strong individual variability automatic 3D algorithms cannot be universally applied: they should be adapted to both image and patient characteristics. [Italian] Scopo: Valutare l'influenza delle curve di opacit� (CO) preimpostate del volume-rendering sulla qualit� delle immagini, ed identificare quali parametri assoluti (attenzione dell'aorta, del parenchima epatico e della vena porta) influenzano la

Visualization of plasma collision phenomenon by particle based rendering

International Nuclear Information System (INIS)

Yamamoto, Takeshi; Takagishi, Hironori; Hasegawa, Kyoko; Nakata, Susumu; Tanaka, Satoshi; Tanaka, Kazuo

2012-01-01

In this paper, we visualize plasma collision phenomenon based on XYT-space (space and time) volume data for supporting research in plasma physics. We create 3D volume data in the XYT-space by piling up a time series of XY-plane photo images taken in experiment. As a result, we can visualize as one still image all the time behavior of the plasma plume. Besides, we adopt 'fused' visualization based on particle based rendering technique. Using that technique, we can easily fuse volume rendering different materials, and compare physics of different elements in flexible ways. In addition, we propose the method to generate pseudo-3D images from pictures shoot by ICCD of two perspectives on the upper and side. (author)

Realistic Real-Time Outdoor Rendering in Augmented Reality

Science.gov (United States)

Kolivand, Hoshang; Sunar, Mohd Shahrizal

2014-01-01

Realistic rendering techniques of outdoor Augmented Reality (AR) has been an attractive topic since the last two decades considering the sizeable amount of publications in computer graphics. Realistic virtual objects in outdoor rendering AR systems require sophisticated effects such as: shadows, daylight and interactions between sky colours and virtual as well as real objects. A few realistic rendering techniques have been designed to overcome this obstacle, most of which are related to non real-time rendering. However, the problem still remains, especially in outdoor rendering. This paper proposed a much newer, unique technique to achieve realistic real-time outdoor rendering, while taking into account the interaction between sky colours and objects in AR systems with respect to shadows in any specific location, date and time. This approach involves three main phases, which cover different outdoor AR rendering requirements. Firstly, sky colour was generated with respect to the position of the sun. Second step involves the shadow generation algorithm, Z-Partitioning: Gaussian and Fog Shadow Maps (Z-GaF Shadow Maps). Lastly, a technique to integrate sky colours and shadows through its effects on virtual objects in the AR system, is introduced. The experimental results reveal that the proposed technique has significantly improved the realism of real-time outdoor AR rendering, thus solving the problem of realistic AR systems. PMID:25268480

Realistic real-time outdoor rendering in augmented reality.

Directory of Open Access Journals (Sweden)

Hoshang Kolivand

Full Text Available Realistic rendering techniques of outdoor Augmented Reality (AR has been an attractive topic since the last two decades considering the sizeable amount of publications in computer graphics. Realistic virtual objects in outdoor rendering AR systems require sophisticated effects such as: shadows, daylight and interactions between sky colours and virtual as well as real objects. A few realistic rendering techniques have been designed to overcome this obstacle, most of which are related to non real-time rendering. However, the problem still remains, especially in outdoor rendering. This paper proposed a much newer, unique technique to achieve realistic real-time outdoor rendering, while taking into account the interaction between sky colours and objects in AR systems with respect to shadows in any specific location, date and time. This approach involves three main phases, which cover different outdoor AR rendering requirements. Firstly, sky colour was generated with respect to the position of the sun. Second step involves the shadow generation algorithm, Z-Partitioning: Gaussian and Fog Shadow Maps (Z-GaF Shadow Maps. Lastly, a technique to integrate sky colours and shadows through its effects on virtual objects in the AR system, is introduced. The experimental results reveal that the proposed technique has significantly improved the realism of real-time outdoor AR rendering, thus solving the problem of realistic AR systems.

Distributed rendering for multiview parallax displays

Science.gov (United States)

Annen, T.; Matusik, W.; Pfister, H.; Seidel, H.-P.; Zwicker, M.

2006-02-01

3D display technology holds great promise for the future of television, virtual reality, entertainment, and visualization. Multiview parallax displays deliver stereoscopic views without glasses to arbitrary positions within the viewing zone. These systems must include a high-performance and scalable 3D rendering subsystem in order to generate multiple views at real-time frame rates. This paper describes a distributed rendering system for large-scale multiview parallax displays built with a network of PCs, commodity graphics accelerators, multiple projectors, and multiview screens. The main challenge is to render various perspective views of the scene and assign rendering tasks effectively. In this paper we investigate two different approaches: Optical multiplexing for lenticular screens and software multiplexing for parallax-barrier displays. We describe the construction of large-scale multi-projector 3D display systems using lenticular and parallax-barrier technology. We have developed different distributed rendering algorithms using the Chromium stream-processing framework and evaluate the trade-offs and performance bottlenecks. Our results show that Chromium is well suited for interactive rendering on multiview parallax displays.

Three-dimensional volume rendering of tibiofibular joint space and quantitative analysis of change in volume due to tibiofibular syndesmosis diastases

International Nuclear Information System (INIS)

Taser, F.; Shafiq, Q.; Ebraheim, N.A.

2006-01-01

The diagnosis of ankle syndesmosis injuries is made by various imaging techniques. The present study was undertaken to examine whether the three-dimensional reconstruction of axial CT images and calculation of the volume of tibiofibular joint space enhances the sensitivity of diastases diagnoses or not. Six adult cadaveric ankle specimens were used for spiral CT-scan assessment of tibiofibular syndesmosis. After the specimens were dissected, external fixation was performed and diastases of 1, 2, and 3 mm was simulated by a precalibrated device. Helical CT scans were obtained with 1.0-mm slice thickness. The data was transferred to the computer software AcquariusNET. Then the contours of the tibiofibular syndesmosis joint space were outlined on each axial CT slice and the collection of these slices were stacked using the computer software AutoCAD 2005, according to the spatial arrangement and geometrical coordinates between each slice, to produce a three-dimensional reconstruction of the joint space. The area of each slice and the volume of the entire tibiofibular joint space were calculated. The tibiofibular joint space at the 10th-mm slice level was also measured on axial CT scan images at normal, 1, 2 and 3-mm joint space diastases. The three-dimensional volume-rendering of the tibiofibular syndesmosis joint space from the spiral CT data demonstrated the shape of the joint space and has been found to be a sensitive method for calculating joint space volume. We found that, from normal to 1 mm, a 1-mm diastasis increases approximately 43% of the joint space volume, while from 1 to 3 mm, there is about a 20% increase for each 1-mm increase. Volume calculation using this method can be performed in cases of syndesmotic instability after ankle injuries and for preoperative and postoperative evaluation of the integrity of the tibiofibular syndesmosis. (orig.)

3D reconstruction from X-ray fluoroscopy for clinical veterinary medicine using differential volume rendering

International Nuclear Information System (INIS)

Khongsomboon, K.; Hamamoto, Kazuhiko; Kondo, Shozo

2007-01-01

3D reconstruction from ordinary X-ray equipment which is not CT or MRI is required in clinical veterinary medicine. Authors have already proposed a 3D reconstruction technique from X-ray photograph to present bone structure. Although the reconstruction is useful for veterinary medicine, the technique has two problems. One is about exposure of X-ray and the other is about data acquisition process. An x-ray equipment which is not special one but can solve the problems is X-ray fluoroscopy. Therefore, in this paper, we propose a method for 3D-reconstruction from X-ray fluoroscopy for clinical veterinary medicine. Fluoroscopy is usually used to observe a movement of organ or to identify a position of organ for surgery by weak X-ray intensity. Since fluoroscopy can output a observed result as movie, the previous two problems which are caused by use of X-ray photograph can be solved. However, a new problem arises due to weak X-ray intensity. Although fluoroscopy can present information of not only bone structure but soft tissues, the contrast is very low and it is very difficult to recognize some soft tissues. It is very useful to be able to observe not only bone structure but soft tissues clearly by ordinary X-ray equipment in the field of clinical veterinary medicine. To solve this problem, this paper proposes a new method to determine opacity in volume rendering process. The opacity is determined according to 3D differential coefficient of 3D reconstruction. This differential volume rendering can present a 3D structure image of multiple organs volumetrically and clearly for clinical veterinary medicine. This paper shows results of simulation and experimental investigation of small dog and evaluation by veterinarians. (author)

Exploring the use of glossy light volumes for interactive global illumination

CSIR Research Space (South Africa)

Duvenhage, B

2010-06-01

Full Text Available . raytracing. Arvo used backward raytracing to render caustics which could not efficiently be simulated using the high fidelity forward raytracing and radiosity rendering techniques of the time. Similar to what Heckbert and Hanrahan proposed and did, Watt... graphics and interactive tech- niques, ACM, New York, NY, USA, 119–127. HECKBERT, P. 1990. Adaptive radiosity textures for bidirectional ray tracing. In SIGGRAPH ’90: Proceedings of the 17th annual conference on Computer graphics and interactive...

Interactive navigation and bronchial tube tracking in virtual bronchoscopy.

Science.gov (United States)

Heng, P A; Fung, P F; Wong, T T; Siu, Y H; Sun, H

1999-01-01

An interactive virtual environment for simulation of bronchoscopy is developed. Medical doctor can safely plan their surgical bronchoscopy using the virtual environment without any invasive diagnosis which may risk the patient's health. The 3D pen input device of the system allows the doctor to navigate and visualize the bronchial tree of the patient naturally and interactively. To navigate the patient's bronchial tree, a vessel tracking process is required. While manual tracking is tedious and labor-intensive, fully automatic tracking may not be reliable. We propose a semi-automatic tracking technique called Intelligent Path Tracker which provides automation and enough user control during the vessel tracking. To support an interactive frame rate, we also introduce a new volume rendering acceleration technique, named as IsoRegion Leaping. The volume rendering is further accelerated by distributed rendering on a TCP/IP-based network of low-cost PCs. With these approaches, a 256 x 256 x 256 volume data of human lung, can be navigated and visualized at a frame rate of over 10 Hz in our virtual bronchoscopy system.

Technical analysis of volume-rendering algorithms: application in low-contrast structures using liver vascularisation as a model

International Nuclear Information System (INIS)

Cademartiri, Filippo; Luccichenti, Giacomo; Runza, Giuseppe; Bartolotta, Tommaso Vincenzo; Midiri, Massimo; Gualerzi, Massimo; Brambilla, Lorenzo; Coruzzi, Paolo; Soliani, Paolo; Sianesi, Mario

2005-01-01

Purpose: To assess the influence of pre-set volume rendering opacity curves (OC) on image quality and to identify which absolute parameters (density of aorta, hepatic parenchyma and portal vein) affect visualization of portal vascular structures (low-contrast structures). Materials and methods: Twenty-two patients underwent a dual-phase spiral CT with the following parameters: collimation 3 mm, pitch 2, increment 1 mm. Three scans were performed: one without contrast medium and the latter two after the injection of contrast material (conventionally identified as 'arterial' and 'portal'). The images were sent to a workstation running on an NT platform equipped with post-processing software allowing three-dimensional (3D) reconstructions to generate volume-rendered images of the vascular supply to the liver. Correlation between the absolute values of aorta, liver and portal vein density, OC parameters, and image quality were assessed. Results: 3D images generated using pre-set OC obtained a much mower overall quality score than those produced with OC set by the operator. High contrast between the liver and the portal vein, for example during the portal vascular phase, allows wider windows, thus improving image quality. Conversely, the OC in the parenchymal phase scans must have a high gradient in order to better differentiate between the vascular structures and the surrounding hepatic parenchyma. Conclusions: Image features considered to be of interest by the operator cannot be simplified by the mean of pre-set OC. Due to their strong individual variability automatic 3D algorithms cannot be universally applied: they should be adapted to both image and patient characteristics [it

Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering; Die computerassistierte Operationsplanung in der Abdominalchirurgie des Kindes. 3D-Visualisierung mittels ''volume rendering'' in der MRT

Energy Technology Data Exchange (ETDEWEB)

Guenther, P.; Holland-Cunz, S.; Waag, K.L. [Universitaetsklinikum Heidelberg (Germany). Kinderchirurgie; Troeger, J. [Universitaetsklinikum Heidelberg, (Germany). Paediatrische Radiologie; Schenk, J.P. [Universitaetsklinikum Heidelberg, (Germany). Paediatrische Radiologie; Universitaetsklinikum, Paediatrische Radiologie, Heidelberg (Germany)

2006-08-15

Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this. A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning. (orig.) [German] Komplexe Operationen bei ausgepraegten pathologischen Veraenderungen anatomischer Strukturen des kindlichen Abdomens benoetigen eine exakte Operationsvorbereitung. 3D-Visualisierung und computerassistierte Operationsplanung anhand von CT-Daten finden fuer schwierige chirurgische Eingriffe bei Erwachsenen in zunehmendem Masse Anwendung. Aus strahlenhygienischen Gruenden und bei besserer Weichteildifferenzierung ist jedoch neben der Sonographie die Magnetresonanztomographie (MRT) bei Kindern das Diagnostikum der Wahl. Die 3D-Visualisierung dieser MRT-Daten ist dabei jedoch aufgrund vielfaeltiger Schwierigkeiten bisher nicht durchgefuehrt worden, obwohl sich das Gebiet embryonaler Fehlbildungen und Tumoren geradezu anbietet. Vorgestellt wird eine weiterentwickelte und an die Fragestellungen der abdominellen Kinderchirurgie angepasste, sehr leistungsstarke raycastingbasierte 3D-volume-rendering-Software (VG Studio Max 1

Parallel rendering

Science.gov (United States)

Crockett, Thomas W.

1995-01-01

This article provides a broad introduction to the subject of parallel rendering, encompassing both hardware and software systems. The focus is on the underlying concepts and the issues which arise in the design of parallel rendering algorithms and systems. We examine the different types of parallelism and how they can be applied in rendering applications. Concepts from parallel computing, such as data decomposition, task granularity, scalability, and load balancing, are considered in relation to the rendering problem. We also explore concepts from computer graphics, such as coherence and projection, which have a significant impact on the structure of parallel rendering algorithms. Our survey covers a number of practical considerations as well, including the choice of architectural platform, communication and memory requirements, and the problem of image assembly and display. We illustrate the discussion with numerous examples from the parallel rendering literature, representing most of the principal rendering methods currently used in computer graphics.

A Study of Layout, Rendering, and Interaction Methods for Immersive Graph Visualization.

Science.gov (United States)

Kwon, Oh-Hyun; Muelder, Chris; Lee, Kyungwon; Ma, Kwan-Liu

2016-07-01

Information visualization has traditionally limited itself to 2D representations, primarily due to the prevalence of 2D displays and report formats. However, there has been a recent surge in popularity of consumer grade 3D displays and immersive head-mounted displays (HMDs). The ubiquity of such displays enables the possibility of immersive, stereoscopic visualization environments. While techniques that utilize such immersive environments have been explored extensively for spatial and scientific visualizations, contrastingly very little has been explored for information visualization. In this paper, we present our considerations of layout, rendering, and interaction methods for visualizing graphs in an immersive environment. We conducted a user study to evaluate our techniques compared to traditional 2D graph visualization. The results show that participants answered significantly faster with a fewer number of interactions using our techniques, especially for more difficult tasks. While the overall correctness rates are not significantly different, we found that participants gave significantly more correct answers using our techniques for larger graphs.

Three-dimensional reconstructions of the orbital floor by volume-rendering of multidetector-row CT data

International Nuclear Information System (INIS)

Yoshikawa, Tetsuya; Miyajima, Akira; Fujita, Yuko; Yamada, Kazuo

2011-01-01

The advent of 3D-CT has made the evaluation of complicated facial fractures much easier than before. However, its use in injuries involving the orbital floor has been limited by the difficulty of visualizing the thin bony structures given artifacts caused by the partial volume effect. Nevertheless, high-technology machines such as multidetector-row CT (MDCT) and new-generation software have improved the quality of 3D imaging, and this paper describes a procedure for obtaining better visualization of the orbital floor using a MDCT scanner. Forty trauma cases were subject to MDCT: 13 with injury to the orbital floor, and 27 without. All scans were performed in the standard manner, at slice thicknesses of 0.5 mm. 3D-CT images were created overlooking the orbital floor including soft tissue to minimize the pseudo-foramen artifacts produced through volume rendering. Bone deficits, fracture lines, and grafted bone were visible in the 3D images, and visualization was supported by the ready creation of stereoscopic images from MDCT volume data. Measurement of the pseudo-foramen revealed approximately half the artifacts to be less than 5 mm in diameter, suggesting practicality of this method without subjecting the patient to undue increases in radiation exposure in the treatment of cases involving injury to the orbital floor. (author)

A Virtual Reality System for PTCD Simulation Using Direct Visuo-Haptic Rendering of Partially Segmented Image Data.

Science.gov (United States)

Fortmeier, Dirk; Mastmeyer, Andre; Schröder, Julian; Handels, Heinz

2016-01-01

This study presents a new visuo-haptic virtual reality (VR) training and planning system for percutaneous transhepatic cholangio-drainage (PTCD) based on partially segmented virtual patient models. We only use partially segmented image data instead of a full segmentation and circumvent the necessity of surface or volume mesh models. Haptic interaction with the virtual patient during virtual palpation, ultrasound probing and needle insertion is provided. Furthermore, the VR simulator includes X-ray and ultrasound simulation for image-guided training. The visualization techniques are GPU-accelerated by implementation in Cuda and include real-time volume deformations computed on the grid of the image data. Computation on the image grid enables straightforward integration of the deformed image data into the visualization components. To provide shorter rendering times, the performance of the volume deformation algorithm is improved by a multigrid approach. To evaluate the VR training system, a user evaluation has been performed and deformation algorithms are analyzed in terms of convergence speed with respect to a fully converged solution. The user evaluation shows positive results with increased user confidence after a training session. It is shown that using partially segmented patient data and direct volume rendering is suitable for the simulation of needle insertion procedures such as PTCD.

Virtual endoscopy and 3D volume rendering in the management of frontal sinus fractures.

Science.gov (United States)

Belina, Stanko; Cuk, Viseslav; Klapan, Ivica

2009-12-01

Frontal sinus fractures (FSF) are commonly caused by traffic accidents, assaults, industrial accidents and gunshot wounds. Classical roentgenography has high proportion of false negative findings in cases of FSF and is not particularly useful in examining the severity of damage to the frontal sinus posterior table and the nasofrontal duct region. High resolution computed tomography was inavoidable during the management of such patients but it may produce large quantity of 2D images. Postprocessing of datasets acquired by high resolution computer tomography from patients with severe head trauma may offer a valuable additional help in diagnostics and surgery planning. We performed virtual endoscopy (VE) and 3D volume rendering (3DVR) on high resolution CT data acquired from a 54-year-old man with with both anterior and posterior frontal sinus wall fracture in order to demonstrate advantages and disadvantages of these methods. Data acquisition was done by Siemens Somatom Emotion scanner and postprocessing was performed with Syngo 2006G software. VE and 3DVR were performed in a man who suffered blunt trauma to his forehead and nose in an traffic accident. Left frontal sinus anterior wall fracture without dislocation and fracture of tabula interna with dislocation were found. 3D position and orientation of fracture lines were shown in by 3D rendering software. We concluded that VE and 3DVR can clearly display the anatomic structure of the paranasal sinuses and nasopharyngeal cavity, revealing damage to the sinus wall caused by a fracture and its relationship to surrounding anatomical structures.

High Fidelity Haptic Rendering

CERN Document Server

Otaduy, Miguel A

2006-01-01

The human haptic system, among all senses, provides unique and bidirectional communication between humans and their physical environment. Yet, to date, most human-computer interactive systems have focused primarily on the graphical rendering of visual information and, to a lesser extent, on the display of auditory information. Extending the frontier of visual computing, haptic interfaces, or force feedback devices, have the potential to increase the quality of human-computer interaction by accommodating the sense of touch. They provide an attractive augmentation to visual display and enhance t

A Sort-Last Rendering System over an Optical Backplane

Directory of Open Access Journals (Sweden)

Yasuhiro Kirihata

2005-06-01

Full Text Available Sort-Last is a computer graphics technique for rendering extremely large data sets on clusters of computers. Sort-Last works by dividing the data set into even-sized chunks for parallel rendering and then composing the images to form the final result. Since sort-last rendering requires the movement of large amounts of image data among cluster nodes, the network interconnecting the nodes becomes a major bottleneck. In this paper, we describe a sort-last rendering system implemented on a cluster of computers whose nodes are connected by an all-optical switch. The rendering system introduces the notion of the Photonic Computing Engine, a computing system built dynamically by using the optical switch to create dedicated network connections among cluster nodes. The sort-last volume rendering algorithm was implemented on the Photonic Computing Engine, and its performance is evaluated. Prelimi- nary experiments show that performance is affected by the image composition time and average payload size. In an attempt to stabilize the performance of the system, we have designed a flow control mechanism that uses feedback messages to dynamically adjust the data flow rate within the computing engine.

Hybrid fur rendering: combining volumetric fur with explicit hair strands

DEFF Research Database (Denmark)

Andersen, Tobias Grønbeck; Falster, Viggo; Frisvad, Jeppe Revall

2016-01-01

Hair is typically modeled and rendered using either explicitly defined hair strand geometry or a volume texture of hair densities. Taken each on their own, these two hair representations have difficulties in the case of animal fur as it consists of very dense and thin undercoat hairs in combination...... with coarse guard hairs. Explicit hair strand geometry is not well-suited for the undercoat hairs, while volume textures are not well-suited for the guard hairs. To efficiently model and render both guard hairs and undercoat hairs, we present a hybrid technique that combines rasterization of explicitly...... defined guard hairs with ray marching of a prismatic shell volume with dynamic resolution. The latter is the key to practical combination of the two techniques, and it also enables a high degree of detail in the undercoat. We demonstrate that our hybrid technique creates a more detailed and soft fur...

Fast algorithm for the rendering of three-dimensional surfaces

Science.gov (United States)

Pritt, Mark D.

1994-02-01

It is often desirable to draw a detailed and realistic representation of surface data on a computer graphics display. One such representation is a 3D shaded surface. Conventional techniques for rendering shaded surfaces are slow, however, and require substantial computational power. Furthermore, many techniques suffer from aliasing effects, which appear as jagged lines and edges. This paper describes an algorithm for the fast rendering of shaded surfaces without aliasing effects. It is much faster than conventional ray tracing and polygon-based rendering techniques and is suitable for interactive use. On an IBM RISC System/6000TM workstation it renders a 1000 X 1000 surface in about 7 seconds.

Drishti: a volume exploration and presentation tool

Science.gov (United States)

Limaye, Ajay

2012-10-01

Among several rendering techniques for volumetric data, direct volume rendering is a powerful visualization tool for a wide variety of applications. This paper describes the major features of hardware based volume exploration and presentation tool - Drishti. The word, Drishti, stands for vision or insight in Sanskrit, an ancient Indian language. Drishti is a cross-platform open-source volume rendering system that delivers high quality, state of the art renderings. The features in Drishti include, though not limited to, production quality rendering, volume sculpting, multi-resolution zooming, transfer function blending, profile generation, measurement tools, mesh generation, stereo/anaglyph/crosseye renderings. Ultimately, Drishti provides an intuitive and powerful interface for choreographing animations.

Ambient Occlusion Effects for Combined Volumes and Tubular Geometry

KAUST Repository

Schott, M.; Martin, T.; Grosset, A. V. P.; Smith, S. T.; Hansen, C. D.

2013-01-01

This paper details a method for interactive direct volume rendering that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube-shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The algorithm extends the recently presented the directional occlusion shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. Stream tube geometries are computed using an effective spline-based interpolation and approximation scheme that avoids self-intersection and maintains coherent orientation of the stream tube segments to avoid surface deforming twists. Furthermore, strategies to reduce the geometric and specular aliasing of the stream tubes are discussed.

Ambient Occlusion Effects for Combined Volumes and Tubular Geometry

KAUST Repository

Schott, M.

2013-06-01

This paper details a method for interactive direct volume rendering that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube-shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The algorithm extends the recently presented the directional occlusion shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. Stream tube geometries are computed using an effective spline-based interpolation and approximation scheme that avoids self-intersection and maintains coherent orientation of the stream tube segments to avoid surface deforming twists. Furthermore, strategies to reduce the geometric and specular aliasing of the stream tubes are discussed.

Virtual reality in medicine-computer graphics and interaction techniques.

Science.gov (United States)

Haubner, M; Krapichler, C; Lösch, A; Englmeier, K H; van Eimeren, W

1997-03-01

This paper describes several new visualization and interaction techniques that enable the use of virtual environments for routine medical purposes. A new volume-rendering method supports shaded and transparent visualization of medical image sequences in real-time with an interactive threshold definition. Based on these rendering algorithms two complementary segmentation approaches offer an intuitive assistance for a wide range of requirements in diagnosis and therapy planning. In addition, a hierarchical data representation for geometric surface descriptions guarantees an optimal use of available hardware resources and prevents inaccurate visualization. The combination of the presented techniques empowers the improved human-machine interface of virtual reality to support every interactive task in medical three-dimensional (3-D) image processing, from visualization of unsegmented data volumes up to the simulation of surgical procedures.

Three-dimensional volume rendering of the ankle based on magnetic resonance images enables the generation of images comparable to real anatomy.

Science.gov (United States)

Anastasi, Giuseppe; Cutroneo, Giuseppina; Bruschetta, Daniele; Trimarchi, Fabio; Ielitro, Giuseppe; Cammaroto, Simona; Duca, Antonio; Bramanti, Placido; Favaloro, Angelo; Vaccarino, Gianluigi; Milardi, Demetrio

2009-11-01

We have applied high-quality medical imaging techniques to study the structure of the human ankle. Direct volume rendering, using specific algorithms, transforms conventional two-dimensional (2D) magnetic resonance image (MRI) series into 3D volume datasets. This tool allows high-definition visualization of single or multiple structures for diagnostic, research, and teaching purposes. No other image reformatting technique so accurately highlights each anatomic relationship and preserves soft tissue definition. Here, we used this method to study the structure of the human ankle to analyze tendon-bone-muscle relationships. We compared ankle MRI and computerized tomography (CT) images from 17 healthy volunteers, aged 18-30 years (mean 23 years). An additional subject had a partial rupture of the Achilles tendon. The MRI images demonstrated superiority in overall quality of detail compared to the CT images. The MRI series accurately rendered soft tissue and bone in simultaneous image acquisition, whereas CT required several window-reformatting algorithms, with loss of image data quality. We obtained high-quality digital images of the human ankle that were sufficiently accurate for surgical and clinical intervention planning, as well as for teaching human anatomy. Our approach demonstrates that complex anatomical structures such as the ankle, which is rich in articular facets and ligaments, can be easily studied non-invasively using MRI data.

Activation volume and interaction of metal particulate media

Energy Technology Data Exchange (ETDEWEB)

Tetsukawa, Hiroki [Sony Corporation, 6-7-35 Kitashinagawa, Shinagawa-ku, Tokyo 141-0001 (Japan)]. E-mail: tetsukaw@arc.sony.co.jp; Kondo, Hirofumi [Sony Corporation, 6-7-35 Kitashinagawa, Shinagawa-ku, Tokyo 141-0001 (Japan)

2005-09-15

We have investigated the activation volume (V{sub ac}) and magnetostatic interaction of metal particulate (MP) media. The activation volume of MP media decreases with the decrease of physical volume (V{sub phy}) of metal particles. The activation volume and the ratio of V{sub phy}/V{sub ac} of advanced metal particles are 6x10{sup -24}m{sup 3} and 1.5, respectively. It can be predicted that the physical volume of metal particle is about 3x10{sup -24}m{sup 3} when the physical volume is equal to the activation volume. This value is agreement with the practical lower limit of physical volume of metal particle predicted by Sharrock. The negative interaction (demagnetization effect) in MP media decreases with low saturation magnetization of the metal particles, a thin magnetic layer, a high orientation of MP media, and a low packing fraction of metal particles in the MP media. The activation volume of the MP media decreased as the negative interactions decreased. In advanced MP media with low M{sub r}.t (M{sub r}=remanent magnetization and t=thickness), the influence of interaction on the activation volume is reduced.

Activation volume and interaction of metal particulate media

International Nuclear Information System (INIS)

Tetsukawa, Hiroki; Kondo, Hirofumi

2005-01-01

We have investigated the activation volume (V ac ) and magnetostatic interaction of metal particulate (MP) media. The activation volume of MP media decreases with the decrease of physical volume (V phy ) of metal particles. The activation volume and the ratio of V phy /V ac of advanced metal particles are 6x10 -24 m 3 and 1.5, respectively. It can be predicted that the physical volume of metal particle is about 3x10 -24 m 3 when the physical volume is equal to the activation volume. This value is agreement with the practical lower limit of physical volume of metal particle predicted by Sharrock. The negative interaction (demagnetization effect) in MP media decreases with low saturation magnetization of the metal particles, a thin magnetic layer, a high orientation of MP media, and a low packing fraction of metal particles in the MP media. The activation volume of the MP media decreased as the negative interactions decreased. In advanced MP media with low M r .t (M r =remanent magnetization and t=thickness), the influence of interaction on the activation volume is reduced

GPU Pro advanced rendering techniques

CERN Document Server

Engel, Wolfgang

2010-01-01

This book covers essential tools and techniques for programming the graphics processing unit. Brought to you by Wolfgang Engel and the same team of editors who made the ShaderX series a success, this volume covers advanced rendering techniques, engine design, GPGPU techniques, related mathematical techniques, and game postmortems. A special emphasis is placed on handheld programming to account for the increased importance of graphics on mobile devices, especially the iPhone and iPod touch.Example programs and source code can be downloaded from the book's CRC Press web page. 

[Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering].

Science.gov (United States)

Günther, P; Tröger, J; Holland-Cunz, S; Waag, K L; Schenk, J P

2006-08-01

Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this.A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning.

Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering

International Nuclear Information System (INIS)

Guenther, P.; Holland-Cunz, S.; Waag, K.L.

2006-01-01

Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this. A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning. (orig.) [de

Rendering the Topological Spines

Energy Technology Data Exchange (ETDEWEB)

Nieves-Rivera, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2015-05-05

Many tools to analyze and represent high dimensional data already exits yet most of them are not flexible, informative and intuitive enough to help the scientists make the corresponding analysis and predictions, understand the structure and complexity of scientific data, get a complete picture of it and explore a greater number of hypotheses. With this in mind, N-Dimensional Data Analysis and Visualization (ND²AV) is being developed to serve as an interactive visual analysis platform with the purpose of coupling together a number of these existing tools that range from statistics, machine learning, and data mining, with new techniques, in particular with new visualization approaches. My task is to create the rendering and implementation of a new concept called topological spines in order to extend ND²AV's scope. Other existing visualization tools create a representation preserving either the topological properties or the structural (geometric) ones because it is challenging to preserve them both simultaneously. Overcoming such challenge by creating a balance in between them, the topological spines are introduced as a new approach that aims to preserve them both. Its render using OpenGL and C++ and is currently being tested to further on be implemented on ND²AV. In this paper I will present what are the Topological Spines and how they are rendered.

Haptic rendering for simulation of fine manipulation

CERN Document Server

Wang, Dangxiao; Zhang, Yuru

2014-01-01

This book introduces the latest progress in six degrees of freedom (6-DoF) haptic rendering with the focus on a new approach for simulating force/torque feedback in performing tasks that require dexterous manipulation skills. One of the major challenges in 6-DoF haptic rendering is to resolve the conflict between high speed and high fidelity requirements, especially in simulating a tool interacting with both rigid and deformable objects in a narrow space and with fine features. The book presents a configuration-based optimization approach to tackle this challenge. Addressing a key issue in man

Free-viewpoint depth image based rendering

NARCIS (Netherlands)

Zinger, S.; Do, Q.L.; With, de P.H.N.

2010-01-01

In 3D TV research, one approach is to employ multiple cameras for creating a 3D multi-view signal with the aim to make interactive free-viewpoint selection possible in 3D TV media. This paper explores a new rendering algorithm that enables to compute a free-viewpoint between two reference views from

RenderToolbox3: MATLAB tools that facilitate physically based stimulus rendering for vision research.

Science.gov (United States)

Heasly, Benjamin S; Cottaris, Nicolas P; Lichtman, Daniel P; Xiao, Bei; Brainard, David H

2014-02-07

RenderToolbox3 provides MATLAB utilities and prescribes a workflow that should be useful to researchers who want to employ graphics in the study of vision and perhaps in other endeavors as well. In particular, RenderToolbox3 facilitates rendering scene families in which various scene attributes and renderer behaviors are manipulated parametrically, enables spectral specification of object reflectance and illuminant spectra, enables the use of physically based material specifications, helps validate renderer output, and converts renderer output to physical units of radiance. This paper describes the design and functionality of the toolbox and discusses several examples that demonstrate its use. We have designed RenderToolbox3 to be portable across computer hardware and operating systems and to be free and open source (except for MATLAB itself). RenderToolbox3 is available at https://github.com/DavidBrainard/RenderToolbox3.

Interactive visualization and analysis of 3D medical images for neurosurgery

International Nuclear Information System (INIS)

Miyazawa, Tatsuo; Otsuki, Taisuke.

1994-01-01

We propose a method that makes it possible to interactively rotate and zoom a volume-rendered object and to interactively manipulate a function for transferring data values to color and opacity. The method ray-traces a Value-Intensity-Strength volume (VIS volume) instead of a color-opacity volume, and uses an adaptive refinement technique in generating images. The VIS volume tracing method can reduce by 20-90 percent the computational time of re-calculation necessitated by changing the function for transferring data values to color and opacity, and can reduce the computational time of pre-processing by 20 percent. It can also reduce the required memory space by 40 percent. The combination of VIS volume tracing and adaptive refinement method makes it possible to interactively visualize and analyze 3D medical image data. Once we can see detailed image of 3D objects to determine their orientation, we can easily manipulate the viewing and rendering parameters even while viewing rough, blurred images. The increase in the computation time for generating full-resolution images by using the adaptive refinement technique is approximately five to ten percent. Its effectiveness is evaluated by using the results of visualization for some 3D medical image data. (author)

Beaming teaching application: recording techniques for spatial xylophone sound rendering

DEFF Research Database (Denmark)

Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup

2012-01-01

BEAMING is a telepresence research project aiming at providing a multimodal interaction between two or more participants located at distant locations. One of the BEAMING applications allows a distant teacher to give a xylophone playing lecture to the students. Therefore, rendering of the xylophon...... to spatial improvements mainly in terms of the Apparent Source Width (ASW). Rendered examples are subjectively evaluated in listening tests by comparing them with binaural recording....

GPU PRO 3 Advanced rendering techniques

CERN Document Server

Engel, Wolfgang

2012-01-01

GPU Pro3, the third volume in the GPU Pro book series, offers practical tips and techniques for creating real-time graphics that are useful to beginners and seasoned game and graphics programmers alike. Section editors Wolfgang Engel, Christopher Oat, Carsten Dachsbacher, Wessam Bahnassi, and Sebastien St-Laurent have once again brought together a high-quality collection of cutting-edge techniques for advanced GPU programming. With contributions by more than 50 experts, GPU Pro3: Advanced Rendering Techniques covers battle-tested tips and tricks for creating interesting geometry, realistic sha

[Hybrid 3-D rendering of the thorax and surface-based virtual bronchoscopy in surgical and interventional therapy control].

Science.gov (United States)

Seemann, M D; Gebicke, K; Luboldt, W; Albes, J M; Vollmar, J; Schäfer, J F; Beinert, T; Englmeier, K H; Bitzer, M; Claussen, C D

2001-07-01

The aim of this study was to demonstrate the possibilities of a hybrid rendering method, the combination of a color-coded surface and volume rendering method, with the feasibility of performing surface-based virtual endoscopy with different representation models in the operative and interventional therapy control of the chest. In 6 consecutive patients with partial lung resection (n = 2) and lung transplantation (n = 4) a thin-section spiral computed tomography of the chest was performed. The tracheobronchial system and the introduced metallic stents were visualized using a color-coded surface rendering method. The remaining thoracic structures were visualized using a volume rendering method. For virtual bronchoscopy, the tracheobronchial system was visualized using a triangle surface model, a shaded-surface model and a transparent shaded-surface model. The hybrid 3D visualization uses the advantages of both the color-coded surface and volume rendering methods and facilitates a clear representation of the tracheobronchial system and the complex topographical relationship of morphological and pathological changes without loss of diagnostic information. Performing virtual bronchoscopy with the transparent shaded-surface model facilitates a reasonable to optimal, simultaneous visualization and assessment of the surface structure of the tracheobronchial system and the surrounding mediastinal structures and lesions. Hybrid rendering relieve the morphological assessment of anatomical and pathological changes without the need for time-consuming detailed analysis and presentation of source images. Performing virtual bronchoscopy with a transparent shaded-surface model offers a promising alternative to flexible fiberoptic bronchoscopy.

Advanced Audiovisual Rendering, Gesture-Based Interaction and Distributed Delivery for Immersive and Interactive Media Services

NARCIS (Netherlands)

Niamut, O.A.; Kochale, A.; Ruiz Hidalgo, J.; Macq, J-F.; Kienast, G.

2011-01-01

The media industry is currently being pulled in the often-opposing directions of increased realism (high resolution, stereoscopic, large screen) and personalisation (selection and control of content, availability on many devices). A capture, production, delivery and rendering system capable of

An interactive visualization tool for multi-channel confocal microscopy data in neurobiology research

KAUST Repository

Yong Wan,

2009-11-01

Confocal microscopy is widely used in neurobiology for studying the three-dimensional structure of the nervous system. Confocal image data are often multi-channel, with each channel resulting from a different fluorescent dye or fluorescent protein; one channel may have dense data, while another has sparse; and there are often structures at several spatial scales: subneuronal domains, neurons, and large groups of neurons (brain regions). Even qualitative analysis can therefore require visualization using techniques and parameters fine-tuned to a particular dataset. Despite the plethora of volume rendering techniques that have been available for many years, the techniques standardly used in neurobiological research are somewhat rudimentary, such as looking at image slices or maximal intensity projections. Thus there is a real demand from neurobiologists, and biologists in general, for a flexible visualization tool that allows interactive visualization of multi-channel confocal data, with rapid fine-tuning of parameters to reveal the three-dimensional relationships of structures of interest. Together with neurobiologists, we have designed such a tool, choosing visualization methods to suit the characteristics of confocal data and a typical biologist\\'s workflow. We use interactive volume rendering with intuitive settings for multidimensional transfer functions, multiple render modes and multi-views for multi-channel volume data, and embedding of polygon data into volume data for rendering and editing. As an example, we apply this tool to visualize confocal microscopy datasets of the developing zebrafish visual system.

Chromium Renderserver: Scalable and Open Source Remote RenderingInfrastructure

Energy Technology Data Exchange (ETDEWEB)

Paul, Brian; Ahern, Sean; Bethel, E. Wes; Brugger, Eric; Cook,Rich; Daniel, Jamison; Lewis, Ken; Owen, Jens; Southard, Dale

2007-12-01

Chromium Renderserver (CRRS) is software infrastructure thatprovides the ability for one or more users to run and view image outputfrom unmodified, interactive OpenGL and X11 applications on a remote,parallel computational platform equipped with graphics hardwareaccelerators via industry-standard Layer 7 network protocolsand clientviewers. The new contributions of this work include a solution to theproblem of synchronizing X11 and OpenGL command streams, remote deliveryof parallel hardware-accelerated rendering, and a performance analysis ofseveral different optimizations that are generally applicable to avariety of rendering architectures. CRRSis fully operational, Open Sourcesoftware.

Adaptive statistical iterative reconstruction for volume-rendered computed tomography portovenography. Improvement of image quality

International Nuclear Information System (INIS)

Matsuda, Izuru; Hanaoka, Shohei; Akahane, Masaaki

2010-01-01

Adaptive statistical iterative reconstruction (ASIR) is a reconstruction technique for computed tomography (CT) that reduces image noise. The purpose of our study was to investigate whether ASIR improves the quality of volume-rendered (VR) CT portovenography. Institutional review board approval, with waived consent, was obtained. A total of 19 patients (12 men, 7 women; mean age 69.0 years; range 25-82 years) suspected of having liver lesions underwent three-phase enhanced CT. VR image sets were prepared with both the conventional method and ASIR. The required time to make VR images was recorded. Two radiologists performed independent qualitative evaluations of the image sets. The Wilcoxon signed-rank test was used for statistical analysis. Contrast-noise ratios (CNRs) of the portal and hepatic vein were also evaluated. Overall image quality was significantly improved by ASIR (P<0.0001 and P=0.0155 for each radiologist). ASIR enhanced CNRs of the portal and hepatic vein significantly (P<0.0001). The time required to create VR images was significantly shorter with ASIR (84.7 vs. 117.1 s; P=0.014). ASIR enhances CNRs and improves image quality in VR CT portovenography. It also shortens the time required to create liver VR CT portovenographs. (author)

Physically-Based Rendering of Particle-Based Fluids with Light Transport Effects

Science.gov (United States)

Beddiaf, Ali; Babahenini, Mohamed Chaouki

2018-03-01

Recent interactive rendering approaches aim to efficiently produce images. However, time constraints deeply affect their output accuracy and realism (many light phenomena are poorly or not supported at all). To remedy this issue, in this paper, we propose a physically-based fluid rendering approach. First, while state-of-the-art methods focus on isosurface rendering with only two refractions, our proposal (1) considers the fluid as a heterogeneous participating medium with refractive boundaries, and (2) supports both multiple refractions and scattering. Second, the proposed solution is fully particle-based in the sense that no particles transformation into a grid is required. This interesting feature makes it able to handle many particle types (water, bubble, foam, and sand). On top of that, a medium with different fluids (color, phase function, etc.) can also be rendered.

High-performance GPU-based rendering for real-time, rigid 2D/3D-image registration and motion prediction in radiation oncology.

Science.gov (United States)

Spoerk, Jakob; Gendrin, Christelle; Weber, Christoph; Figl, Michael; Pawiro, Supriyanto Ardjo; Furtado, Hugo; Fabri, Daniella; Bloch, Christoph; Bergmann, Helmar; Gröller, Eduard; Birkfellner, Wolfgang

2012-02-01

A common problem in image-guided radiation therapy (IGRT) of lung cancer as well as other malignant diseases is the compensation of periodic and aperiodic motion during dose delivery. Modern systems for image-guided radiation oncology allow for the acquisition of cone-beam computed tomography data in the treatment room as well as the acquisition of planar radiographs during the treatment. A mid-term research goal is the compensation of tumor target volume motion by 2D/3D Registration. In 2D/3D registration, spatial information on organ location is derived by an iterative comparison of perspective volume renderings, so-called digitally rendered radiographs (DRR) from computed tomography volume data, and planar reference x-rays. Currently, this rendering process is very time consuming, and real-time registration, which should at least provide data on organ position in less than a second, has not come into existence. We present two GPU-based rendering algorithms which generate a DRR of 512×512 pixels size from a CT dataset of 53 MB size at a pace of almost 100 Hz. This rendering rate is feasible by applying a number of algorithmic simplifications which range from alternative volume-driven rendering approaches - namely so-called wobbled splatting - to sub-sampling of the DRR-image by means of specialized raycasting techniques. Furthermore, general purpose graphics processing unit (GPGPU) programming paradigms were consequently utilized. Rendering quality and performance as well as the influence on the quality and performance of the overall registration process were measured and analyzed in detail. The results show that both methods are competitive and pave the way for fast motion compensation by rigid and possibly even non-rigid 2D/3D registration and, beyond that, adaptive filtering of motion models in IGRT. Copyright © 2011. Published by Elsevier GmbH.

High-performance GPU-based rendering for real-time, rigid 2D/3D-image registration and motion prediction in radiation oncology

Energy Technology Data Exchange (ETDEWEB)

Spoerk, Jakob; Gendrin, Christelle; Weber, Christoph [Medical University of Vienna (Austria). Center of Medical Physics and Biomedical Engineering] [and others

2012-07-01

A common problem in image-guided radiation therapy (IGRT) of lung cancer as well as other malignant diseases is the compensation of periodic and aperiodic motion during dose delivery. Modern systems for image-guided radiation oncology allow for the acquisition of cone-beam computed tomography data in the treatment room as well as the acquisition of planar radiographs during the treatment. A mid-term research goal is the compensation of tumor target volume motion by 2D/3D Registration. In 2D/3D registration, spatial information on organ location is derived by an iterative comparison of perspective volume renderings, so-called digitally rendered radiographs (DRR) from computed tomography volume data, and planar reference X-rays. Currently, this rendering process is very time consuming, and real-time registration, which should at least provide data on organ position in less than a second, has not come into existence. We present two GPU-based rendering algorithms which generate a DRR of 512 x 512 pixels size from a CT dataset of 53 MB size at a pace of almost 100 Hz. This rendering rate is feasible by applying a number of algorithmic simplifications which range from alternative volume-driven rendering approaches - namely so-called wobbled splatting - to sub-sampling of the DRR-image by means of specialized raycasting techniques. Furthermore, general purpose graphics processing unit (GPGPU) programming paradigms were consequently utilized. Rendering quality and performance as well as the influence on the quality and performance of the overall registration process were measured and analyzed in detail. The results show that both methods are competitive and pave the way for fast motion compensation by rigid and possibly even non-rigid 2D/3D registration and, beyond that, adaptive filtering of motion models in IGRT. (orig.)

State-of-the-Art in GPU-Based Large-Scale Volume Visualization

KAUST Repository

Beyer, Johanna

2015-05-01

This survey gives an overview of the current state of the art in GPU techniques for interactive large-scale volume visualization. Modern techniques in this field have brought about a sea change in how interactive visualization and analysis of giga-, tera- and petabytes of volume data can be enabled on GPUs. In addition to combining the parallel processing power of GPUs with out-of-core methods and data streaming, a major enabler for interactivity is making both the computational and the visualization effort proportional to the amount and resolution of data that is actually visible on screen, i.e. \\'output-sensitive\\' algorithms and system designs. This leads to recent output-sensitive approaches that are \\'ray-guided\\', \\'visualization-driven\\' or \\'display-aware\\'. In this survey, we focus on these characteristics and propose a new categorization of GPU-based large-scale volume visualization techniques based on the notions of actual output-resolution visibility and the current working set of volume bricks-the current subset of data that is minimally required to produce an output image of the desired display resolution. Furthermore, we discuss the differences and similarities of different rendering and data traversal strategies in volume rendering by putting them into a common context-the notion of address translation. For our purposes here, we view parallel (distributed) visualization using clusters as an orthogonal set of techniques that we do not discuss in detail but that can be used in conjunction with what we present in this survey. © 2015 The Eurographics Association and John Wiley & Sons Ltd.

State-of-the-Art in GPU-Based Large-Scale Volume Visualization

KAUST Repository

Beyer, Johanna; Hadwiger, Markus; Pfister, Hanspeter

2015-01-01

This survey gives an overview of the current state of the art in GPU techniques for interactive large-scale volume visualization. Modern techniques in this field have brought about a sea change in how interactive visualization and analysis of giga-, tera- and petabytes of volume data can be enabled on GPUs. In addition to combining the parallel processing power of GPUs with out-of-core methods and data streaming, a major enabler for interactivity is making both the computational and the visualization effort proportional to the amount and resolution of data that is actually visible on screen, i.e. 'output-sensitive' algorithms and system designs. This leads to recent output-sensitive approaches that are 'ray-guided', 'visualization-driven' or 'display-aware'. In this survey, we focus on these characteristics and propose a new categorization of GPU-based large-scale volume visualization techniques based on the notions of actual output-resolution visibility and the current working set of volume bricks-the current subset of data that is minimally required to produce an output image of the desired display resolution. Furthermore, we discuss the differences and similarities of different rendering and data traversal strategies in volume rendering by putting them into a common context-the notion of address translation. For our purposes here, we view parallel (distributed) visualization using clusters as an orthogonal set of techniques that we do not discuss in detail but that can be used in conjunction with what we present in this survey. © 2015 The Eurographics Association and John Wiley & Sons Ltd.

Interactive visual exploration of a trillion particles

KAUST Repository

Schatz, Karsten

2017-03-10

We present a method for the interactive exploration of tera-scale particle data sets. Such data sets arise from molecular dynamics, particle-based fluid simulation, and astrophysics. Our visualization technique provides a focus+context view of the data that runs interactively on commodity hardware. The method is based on a hybrid multi-scale rendering architecture, which renders the context as a hierarchical density volume. Fine details in the focus are visualized using direct particle rendering. In addition, clusters like dark matter halos can be visualized as semi-transparent spheres enclosing the particles. Since the detail data is too large to be stored in main memory, our approach uses an out-of-core technique that streams data on demand. Our technique is designed to take advantage of a dual-GPU configuration, in which the workload is split between the GPUs based on the type of data. Structural features in the data are visually enhanced using advanced rendering and shading techniques. To allow users to easily identify interesting locations even in overviews, both the focus and context view use color tables to show data attributes on the respective scale. We demonstrate that our technique achieves interactive performance on a one trillionpar-ticle data set from the DarkSky simulation.

Three-dimensional rendering of segmented object using matlab - biomed 2010.

Science.gov (United States)

Anderson, Jeffrey R; Barrett, Steven F

2010-01-01

The three-dimensional rendering of microscopic objects is a difficult and challenging task that often requires specialized image processing techniques. Previous work has been described of a semi-automatic segmentation process of fluorescently stained neurons collected as a sequence of slice images with a confocal laser scanning microscope. Once properly segmented, each individual object can be rendered and studied as a three-dimensional virtual object. This paper describes the work associated with the design and development of Matlab files to create three-dimensional images from the segmented object data previously mentioned. Part of the motivation for this work is to integrate both the segmentation and rendering processes into one software application, providing a seamless transition from the segmentation tasks to the rendering and visualization tasks. Previously these tasks were accomplished on two different computer systems, windows and Linux. This transition basically limits the usefulness of the segmentation and rendering applications to those who have both computer systems readily available. The focus of this work is to create custom Matlab image processing algorithms for object rendering and visualization, and merge these capabilities to the Matlab files that were developed especially for the image segmentation task. The completed Matlab application will contain both the segmentation and rendering processes in a single graphical user interface, or GUI. This process for rendering three-dimensional images in Matlab requires that a sequence of two-dimensional binary images, representing a cross-sectional slice of the object, be reassembled in a 3D space, and covered with a surface. Additional segmented objects can be rendered in the same 3D space. The surface properties of each object can be varied by the user to aid in the study and analysis of the objects. This inter-active process becomes a powerful visual tool to study and understand microscopic objects.

Rendering Falling Leaves on Graphics Hardware

OpenAIRE

Marcos Balsa; Pere-Pau Vázquez

2008-01-01

There is a growing interest in simulating natural phenomena in computer graphics applications. Animating natural scenes in real time is one of the most challenging problems due to the inherent complexity of their structure, formed by millions of geometric entities, and the interactions that happen within. An example of natural scenario that is needed for games or simulation programs are forests. Forests are difficult to render because the huge amount of geometric entities and the large amount...

Interactive Dynamic Volume Illumination with Refraction and Caustics.

Science.gov (United States)

Magnus, Jens G; Bruckner, Stefan

2018-01-01

In recent years, significant progress has been made in developing high-quality interactive methods for realistic volume illumination. However, refraction - despite being an important aspect of light propagation in participating media - has so far only received little attention. In this paper, we present a novel approach for refractive volume illumination including caustics capable of interactive frame rates. By interleaving light and viewing ray propagation, our technique avoids memory-intensive storage of illumination information and does not require any precomputation. It is fully dynamic and all parameters such as light position and transfer function can be modified interactively without a performance penalty.

Conservation of old renderings - the consolidation of rendering with loss of cohesion

Directory of Open Access Journals (Sweden)

Martha Tavares

2008-01-01

Full Text Available The study of external renderings in the scope of conservation and restoration has acquired in the last years great methodological, scientific and technical advances. These renderings are important elements of the built structure, for besides possessing a protection function, they possess often a decorative function of great relevance for the image of the monument. The maintenance of these renderings implies the conservation of traditional constructive techniques and the use of compatible materials, as similar to the originals as possible. The main objective of this study is to define a methodology of conservative restoration using strategies of maintenance of renderings and traditional constructive techniques. The minimum intervention principle is maintained as well as the use of materials compatible with the original ones. This paper describes the technique and products used for the consolidation of the loss of cohesion. The testing campaign was developed under controlled conditions, in laboratory, and in situ in order to evaluate their efficacy for the consolidation of old renders. A set of tests is presented to evaluate the effectiveness of the process. The results are analysed and a reflection is added referring to the applicability of these techniques. Finally the paper presents a proposal for further research.

D.Vanwijnsberghe, Autour de la Madeleine Renders

Directory of Open Access Journals (Sweden)

Muriel Verbeeck-Boutin

2008-10-01

Full Text Available Institution fédérale belge de réputation internationale, l’Institut royal du Patrimoine artistique, à Bruxelles,  célèbre cette année son soixantième anniversaire: c’est l’occasion de rappeler le prestige dont jouit depuis des décennies cet institut de recherche, de formation et de diffusion du savoir. Pour souligner l’événement, l’IRPA publie le quatrième volume de la collection Scientia Artis. Il présente sous le titre Autour de la Madeleine Renders un ensemble de recherches qui documentent...

INCREASING SAVING BEHAVIOR THROUGH AGE-PROGRESSED RENDERINGS OF THE FUTURE SELF

Science.gov (United States)

HERSHFIELD, HAL E.; GOLDSTEIN, DANIEL G.; SHARPE, WILLIAM F.; FOX, JESSE; YEYKELIS, LEO; CARSTENSEN, LAURA L.; BAILENSON, JEREMY N.

2014-01-01

Many people fail to save what they need to for retirement (Munnell, Webb, and Golub-Sass 2009). Research on excessive discounting of the future suggests that removing the lure of immediate rewards by pre-committing to decisions, or elaborating the value of future rewards can both make decisions more future-oriented. In this article, we explore a third and complementary route, one that deals not with present and future rewards, but with present and future selves. In line with thinkers who have suggested that people may fail, through a lack of belief or imagination, to identify with their future selves (Parfit 1971; Schelling 1984), we propose that allowing people to interact with age-progressed renderings of themselves will cause them to allocate more resources toward the future. In four studies, participants interacted with realistic computer renderings of their future selves using immersive virtual reality hardware and interactive decision aids. In all cases, those who interacted with virtual future selves exhibited an increased tendency to accept later monetary rewards over immediate ones. PMID:24634544

INCREASING SAVING BEHAVIOR THROUGH AGE-PROGRESSED RENDERINGS OF THE FUTURE SELF.

Science.gov (United States)

Hershfield, Hal E; Goldstein, Daniel G; Sharpe, William F; Fox, Jesse; Yeykelis, Leo; Carstensen, Laura L; Bailenson, Jeremy N

2011-11-01

Many people fail to save what they need to for retirement (Munnell, Webb, and Golub-Sass 2009). Research on excessive discounting of the future suggests that removing the lure of immediate rewards by pre-committing to decisions, or elaborating the value of future rewards can both make decisions more future-oriented. In this article, we explore a third and complementary route, one that deals not with present and future rewards, but with present and future selves. In line with thinkers who have suggested that people may fail, through a lack of belief or imagination, to identify with their future selves (Parfit 1971; Schelling 1984), we propose that allowing people to interact with age-progressed renderings of themselves will cause them to allocate more resources toward the future. In four studies, participants interacted with realistic computer renderings of their future selves using immersive virtual reality hardware and interactive decision aids. In all cases, those who interacted with virtual future selves exhibited an increased tendency to accept later monetary rewards over immediate ones.

The effects of multiview depth video compression on multiview rendering

NARCIS (Netherlands)

Merkle, P.; Morvan, Y.; Smolic, A.; Farin, D.S.; Mueller, K.; With, de P.H.N.; Wiegang, T.

2009-01-01

This article investigates the interaction between different techniques for depth compression and view synthesis rendering with multiview video plus scene depth data. Two different approaches for depth coding are compared, namely H.264/MVC, using temporal and inter-view reference images for efficient

Rendering of Gemstones

OpenAIRE

Krtek, Lukáš

2012-01-01

The distinctive appearance of gemstones is caused by the way light reflects and refracts multiple times inside of them. The goal of this thesis is to design and implement an application for photorealistic rendering of gems. The most important effects we aim for are realistic dispersion of light and refractive caustics. For rendering we use well-known algorithm of path tracing with an experimental modification for faster computation of caustic effects. In this thesis we also design and impleme...

Irregular Morphing for Real-Time Rendering of Large Terrain

Directory of Open Access Journals (Sweden)

S. Kalem

2016-06-01

Full Text Available The following paper proposes an alternative approach to the real-time adaptive triangulation problem. A new region-based multi-resolution approach for terrain rendering is described which improves on-the-fly the distribution of the density of triangles inside the tile after selecting appropriate Level-Of-Detail by an adaptive sampling. This proposed approach organizes the heightmap into a QuadTree of tiles that are processed independently. This technique combines the benefits of both Triangular Irregular Network approach and region-based multi-resolution approach by improving the distribution of the density of triangles inside the tile. Our technique morphs the initial regular grid of the tile to deformed grid in order to minimize approximation error. The proposed technique strives to combine large tile size and real-time processing while guaranteeing an upper bound on the screen space error. Thus, this approach adapts terrain rendering process to local surface characteristics and enables on-the-fly handling of large amount of terrain data. Morphing is based-on the multi-resolution wavelet analysis. The use of the D2WT multi-resolution analysis of the terrain height-map speeds up processing and permits to satisfy an interactive terrain rendering. Tests and experiments demonstrate that Haar B-Spline wavelet, well known for its properties of localization and its compact support, is suitable for fast and accurate redistribution. Such technique could be exploited in client-server architecture for supporting interactive high-quality remote visualization of very large terrain.

Common crus aplasia: diagnosis by 3D volume rendering imaging using 3DFT-CISS sequence

International Nuclear Information System (INIS)

Kim, H.J.; Song, J.W.; Chon, K.-M.; Goh, E.-K.

2004-01-01

AIM: The purpose of this study was to evaluate the findings of three-dimensional (3D) volume rendering (VR) imaging in common crus aplasia (CCA) of the inner ear. MATERIALS AND METHODS: Using 3D VR imaging of temporal bone constructive interference in steady state (CISS) magnetic resonance (MR) images, we retrospectively reviewed seven inner ears of six children who were candidates for cochlear implants and who had been diagnosed with CCA. As controls, we used the same method to examine 402 inner ears of 201 patients who had no clinical symptoms or signs of sensorineural hearing loss. Temporal bone MR imaging (MRI) was performed with a 1.5 T MR machine using a CISS sequence, and VR of the inner ear was performed on a work station. Morphological image analysis was performed on rotation views of 3D VR images. RESULTS: In all seven cases, CCA was diagnosed by the absence of the common crus. The remaining superior semicircular canal (SCC) was normal in five and hypoplastic in two inner ears, while the posterior SCC was normal in all seven. One patient showed bilateral symmetrical CCA. Complicated combined anomalies were seen in the cochlea, vestibule and lateral SCC. CONCLUSION: 3D VR imaging findings with MR CISS sequence can directly diagnose CCA. This technique may be useful in delineating detailed anomalies of SCCs

Haptic rendering foundations, algorithms, and applications

CERN Document Server

Lin, Ming C

2008-01-01

For a long time, human beings have dreamed of a virtual world where it is possible to interact with synthetic entities as if they were real. It has been shown that the ability to touch virtual objects increases the sense of presence in virtual environments. This book provides an authoritative overview of state-of-theart haptic rendering algorithms and their applications. The authors examine various approaches and techniques for designing touch-enabled interfaces for a number of applications, including medical training, model design, and maintainability analysis for virtual prototyping, scienti

GPU Pro 4 advanced rendering techniques

CERN Document Server

Engel, Wolfgang

2013-01-01

GPU Pro4: Advanced Rendering Techniques presents ready-to-use ideas and procedures that can help solve many of your day-to-day graphics programming challenges. Focusing on interactive media and games, the book covers up-to-date methods producing real-time graphics. Section editors Wolfgang Engel, Christopher Oat, Carsten Dachsbacher, Michal Valient, Wessam Bahnassi, and Sebastien St-Laurent have once again assembled a high-quality collection of cutting-edge techniques for advanced graphics processing unit (GPU) programming. Divided into six sections, the book begins with discussions on the abi

Transformative Rendering of Internet Resources

Science.gov (United States)

2012-10-01

using either the Firefox or Google Chrome rendering engine. The rendering server then captures a screen shot of the page and creates code that positions...be compromised at web pages the hackers had built for that hacking competition to exploit that particular OS /browser configuration. During...of risk with no benefit. They include: - The rendering server is hosted on a Linux-based operating system ( OS ). The OS is much more secure than the

Streaming Model Based Volume Ray Casting Implementation for Cell Broadband Engine

Directory of Open Access Journals (Sweden)

Jusub Kim

2009-01-01

Full Text Available Interactive high quality volume rendering is becoming increasingly more important as the amount of more complex volumetric data steadily grows. While a number of volumetric rendering techniques have been widely used, ray casting has been recognized as an effective approach for generating high quality visualization. However, for most users, the use of ray casting has been limited to datasets that are very small because of its high demands on computational power and memory bandwidth. However the recent introduction of the Cell Broadband Engine (Cell B.E. processor, which consists of 9 heterogeneous cores designed to handle extremely demanding computations with large streams of data, provides an opportunity to put the ray casting into practical use. In this paper, we introduce an efficient parallel implementation of volume ray casting on the Cell B.E. The implementation is designed to take full advantage of the computational power and memory bandwidth of the Cell B.E. using an intricate orchestration of the ray casting computation on the available heterogeneous resources. Specifically, we introduce streaming model based schemes and techniques to efficiently implement acceleration techniques for ray casting on Cell B.E. In addition to ensuring effective SIMD utilization, our method provides two key benefits: there is no cost for empty space skipping and there is no memory bottleneck on moving volumetric data for processing. Our experimental results show that we can interactively render practical datasets on a single Cell B.E. processor.

FluoRender: An application of 2D image space methods for 3D and 4D confocal microscopy data visualization in neurobiology research

KAUST Repository

Wan, Yong; Otsuna, Hideo; Chien, Chi-Bin; Hansen, Charles

2012-01-01

2D image space methods are processing methods applied after the volumetric data are projected and rendered into the 2D image space, such as 2D filtering, tone mapping and compositing. In the application domain of volume visualization, most 2D image space methods can be carried out more efficiently than their 3D counterparts. Most importantly, 2D image space methods can be used to enhance volume visualization quality when applied together with volume rendering methods. In this paper, we present and discuss the applications of a series of 2D image space methods as enhancements to confocal microscopy visualizations, including 2D tone mapping, 2D compositing, and 2D color mapping. These methods are easily integrated with our existing confocal visualization tool, FluoRender, and the outcome is a full-featured visualization system that meets neurobiologists' demands for qualitative analysis of confocal microscopy data. © 2012 IEEE.

FluoRender: An application of 2D image space methods for 3D and 4D confocal microscopy data visualization in neurobiology research

KAUST Repository

Wan, Yong

2012-02-01

2D image space methods are processing methods applied after the volumetric data are projected and rendered into the 2D image space, such as 2D filtering, tone mapping and compositing. In the application domain of volume visualization, most 2D image space methods can be carried out more efficiently than their 3D counterparts. Most importantly, 2D image space methods can be used to enhance volume visualization quality when applied together with volume rendering methods. In this paper, we present and discuss the applications of a series of 2D image space methods as enhancements to confocal microscopy visualizations, including 2D tone mapping, 2D compositing, and 2D color mapping. These methods are easily integrated with our existing confocal visualization tool, FluoRender, and the outcome is a full-featured visualization system that meets neurobiologists\\' demands for qualitative analysis of confocal microscopy data. © 2012 IEEE.

Clinical Application of an Open-Source 3D Volume Rendering Software to Neurosurgical Approaches.

Science.gov (United States)

Fernandes de Oliveira Santos, Bruno; Silva da Costa, Marcos Devanir; Centeno, Ricardo Silva; Cavalheiro, Sergio; Antônio de Paiva Neto, Manoel; Lawton, Michael T; Chaddad-Neto, Feres

2018-02-01

Preoperative recognition of the anatomic individualities of each patient can help to achieve more precise and less invasive approaches. It also may help to anticipate potential complications and intraoperative difficulties. Here we describe the use, accuracy, and precision of a free tool for planning microsurgical approaches using 3-dimensional (3D) reconstructions from magnetic resonance imaging (MRI). We used the 3D volume rendering tool of a free open-source software program for 3D reconstruction of images of surgical sites obtained by MRI volumetric acquisition. We recorded anatomic reference points, such as the sulcus and gyrus, and vascularization patterns for intraoperative localization of lesions. Lesion locations were confirmed during surgery by intraoperative ultrasound and/or electrocorticography and later by postoperative MRI. Between August 2015 and September 2016, a total of 23 surgeries were performed using this technique for 9 low-grade gliomas, 7 high-grade gliomas, 4 cortical dysplasias, and 3 arteriovenous malformations. The technique helped delineate lesions with an overall accuracy of 2.6 ± 1.0 mm. 3D reconstructions were successfully performed in all patients, and images showed sulcus, gyrus, and venous patterns corresponding to the intraoperative images. All lesion areas were confirmed both intraoperatively and at the postoperative evaluation. With the technique described herein, it was possible to successfully perform 3D reconstruction of the cortical surface. This reconstruction tool may serve as an adjunct to neuronavigation systems or may be used alone when such a system is unavailable. Copyright © 2017 Elsevier Inc. All rights reserved.

Note: Nonpolar solute partial molar volume response to attractive interactions with water

Energy Technology Data Exchange (ETDEWEB)

Williams, Steven M.; Ashbaugh, Henry S., E-mail: hanka@tulane.edu [Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118 (United States)

2014-01-07

The impact of attractive interactions on the partial molar volumes of methane-like solutes in water is characterized using molecular simulations. Attractions account for a significant 20% volume drop between a repulsive Weeks-Chandler-Andersen and full Lennard-Jones description of methane interactions. The response of the volume to interaction perturbations is characterized by linear fits to our simulations and a rigorous statistical thermodynamic expression for the derivative of the volume to increasing attractions. While a weak non-linear response is observed, an average effective slope accurately captures the volume decrease. This response, however, is anticipated to become more non-linear with increasing solute size.

Note: Nonpolar solute partial molar volume response to attractive interactions with water.

Science.gov (United States)

Williams, Steven M; Ashbaugh, Henry S

2014-01-07

The impact of attractive interactions on the partial molar volumes of methane-like solutes in water is characterized using molecular simulations. Attractions account for a significant 20% volume drop between a repulsive Weeks-Chandler-Andersen and full Lennard-Jones description of methane interactions. The response of the volume to interaction perturbations is characterized by linear fits to our simulations and a rigorous statistical thermodynamic expression for the derivative of the volume to increasing attractions. While a weak non-linear response is observed, an average effective slope accurately captures the volume decrease. This response, however, is anticipated to become more non-linear with increasing solute size.

Reflection curves—new computation and rendering techniques

Directory of Open Access Journals (Sweden)

Dan-Eugen Ulmet

2004-05-01

Full Text Available Reflection curves on surfaces are important tools for free-form surface interrogation. They are essential for industrial 3D CAD/CAM systems and for rendering purposes. In this note, new approaches regarding the computation and rendering of reflection curves on surfaces are introduced. These approaches are designed to take the advantage of the graphics libraries of recent releases of commercial systems such as the OpenInventor toolkit (developed by Silicon Graphics or Matlab (developed by The Math Works. A new relation between reflection curves and contour curves is derived; this theoretical result is used for a straightforward Matlab implementation of reflection curves. A new type of reflection curves is also generated using the OpenInventor texture and environment mapping implementations. This allows the computation, rendering, and animation of reflection curves at interactive rates, which makes it particularly useful for industrial applications.

Remote parallel rendering for high-resolution tiled display walls

KAUST Repository

Nachbaur, Daniel; Dumusc, Raphael; Bilgili, Ahmet; Hernando, Juan; Eilemann, Stefan

2014-01-01

© 2014 IEEE. We present a complete, robust and simple to use hardware and software stack delivering remote parallel rendering of complex geometrical and volumetric models to high resolution tiled display walls in a production environment. We describe the setup and configuration, present preliminary benchmarks showing interactive framerates, and describe our contributions for a seamless integration of all the software components.

Remote parallel rendering for high-resolution tiled display walls

KAUST Repository

Nachbaur, Daniel

2014-11-01

© 2014 IEEE. We present a complete, robust and simple to use hardware and software stack delivering remote parallel rendering of complex geometrical and volumetric models to high resolution tiled display walls in a production environment. We describe the setup and configuration, present preliminary benchmarks showing interactive framerates, and describe our contributions for a seamless integration of all the software components.

Sketchy Rendering for Information Visualization

NARCIS (Netherlands)

Wood, Jo; Isenberg, Petra; Isenberg, Tobias; Dykes, Jason; Boukhelifa, Nadia; Slingsby, Aidan

2012-01-01

We present and evaluate a framework for constructing sketchy style information visualizations that mimic data graphics drawn by hand. We provide an alternative renderer for the Processing graphics environment that redefines core drawing primitives including line, polygon and ellipse rendering. These

Earthscape, a Multi-Purpose Interactive 3d Globe Viewer for Hybrid Data Visualization and Analysis

Science.gov (United States)

Sarthou, A.; Mas, S.; Jacquin, M.; Moreno, N.; Salamon, A.

2015-08-01

The hybrid visualization and interaction tool EarthScape is presented here. The software is able to display simultaneously LiDAR point clouds, draped videos with moving footprint, volume scientific data (using volume rendering, isosurface and slice plane), raster data such as still satellite images, vector data and 3D models such as buildings or vehicles. The application runs on touch screen devices such as tablets. The software is based on open source libraries, such as OpenSceneGraph, osgEarth and OpenCV, and shader programming is used to implement volume rendering of scientific data. The next goal of EarthScape is to perform data analysis using ENVI Services Engine, a cloud data analysis solution. EarthScape is also designed to be a client of Jagwire which provides multisource geo-referenced video fluxes. When all these components will be included, EarthScape will be a multi-purpose platform that will provide at the same time data analysis, hybrid visualization and complex interactions. The software is available on demand for free at france@exelisvis.com.

EARTHSCAPE, A MULTI-PURPOSE INTERACTIVE 3D GLOBE VIEWER FOR HYBRID DATA VISUALIZATION AND ANALYSIS

Directory of Open Access Journals (Sweden)

A. Sarthou

2015-08-01

Full Text Available The hybrid visualization and interaction tool EarthScape is presented here. The software is able to display simultaneously LiDAR point clouds, draped videos with moving footprint, volume scientific data (using volume rendering, isosurface and slice plane, raster data such as still satellite images, vector data and 3D models such as buildings or vehicles. The application runs on touch screen devices such as tablets. The software is based on open source libraries, such as OpenSceneGraph, osgEarth and OpenCV, and shader programming is used to implement volume rendering of scientific data. The next goal of EarthScape is to perform data analysis using ENVI Services Engine, a cloud data analysis solution. EarthScape is also designed to be a client of Jagwire which provides multisource geo-referenced video fluxes. When all these components will be included, EarthScape will be a multi-purpose platform that will provide at the same time data analysis, hybrid visualization and complex interactions. The software is available on demand for free at france@exelisvis.com.

Developing a Tile-Based Rendering Method to Improve Rendering Speed of 3D Geospatial Data with HTML5 and WebGL

Directory of Open Access Journals (Sweden)

Seokchan Kang

2017-01-01

Full Text Available A dedicated plug-in has been installed to visualize three-dimensional (3D city modeling spatial data in web-based applications. However, plug-in methods are gradually becoming obsolete, owing to their limited performance with respect to installation errors, unsupported cross-browsers, and security vulnerability. Particularly, in 2015, the NPAPI service was terminated in most existing web browsers except Internet Explorer. To overcome these problems, the HTML5/WebGL (next-generation web standard, confirmed in October 2014 technology emerged. In particular, WebGL is able to display 3D spatial data without plug-ins in browsers. In this study, we attempted to identify the requirements and limitations of displaying 3D city modeling spatial data using HTML5/WebGL, and we propose alternative ways based on the bin-packing algorithm that aggregates individual 3D city modeling data including buildings in tile units. The proposed method reduces the operational complexity and the number and volume of transmissions required for rendering processing to improve the speed of 3D data rendering. The proposed method was validated on real data for evaluating its effectiveness in 3D visualization of city modeling data in web-based applications.

Real-time photorealistic stereoscopic rendering of fire

Science.gov (United States)

Rose, Benjamin M.; McAllister, David F.

2007-02-01

We propose a method for real-time photorealistic stereo rendering of the natural phenomenon of fire. Applications include the use of virtual reality in fire fighting, military training, and entertainment. Rendering fire in real-time presents a challenge because of the transparency and non-static fluid-like behavior of fire. It is well known that, in general, methods that are effective for monoscopic rendering are not necessarily easily extended to stereo rendering because monoscopic methods often do not provide the depth information necessary to produce the parallax required for binocular disparity in stereoscopic rendering. We investigate the existing techniques used for monoscopic rendering of fire and discuss their suitability for extension to real-time stereo rendering. Methods include the use of precomputed textures, dynamic generation of textures, and rendering models resulting from the approximation of solutions of fluid dynamics equations through the use of ray-tracing algorithms. We have found that in order to attain real-time frame rates, our method based on billboarding is effective. Slicing is used to simulate depth. Texture mapping or 2D images are mapped onto polygons and alpha blending is used to treat transparency. We can use video recordings or prerendered high-quality images of fire as textures to attain photorealistic stereo.

CT portography by multidetector helical CT. Comparison of three rendering models

International Nuclear Information System (INIS)

Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki

2002-01-01

The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

CT portography by multidetector helical CT. Comparison of three rendering models

Energy Technology Data Exchange (ETDEWEB)

Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki [Kumamoto Univ. (Japan). School of Medicine

2002-12-01

The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

Volume Ray Casting with Peak Finding and Differential Sampling

KAUST Repository

Knoll, A.; Hijazi, Y.; Westerteiger, R.; Schott, M.; Hansen, C.; Hagen, H.

2009-01-01

classification. In this paper, we introduce a method for rendering such features by explicitly solving for isovalues within the volume rendering integral. In addition, we present a sampling strategy inspired by ray differentials that automatically matches

Water driven leaching of biocides from paints and renders

DEFF Research Database (Denmark)

Bester, Kai; Vollertsen, Jes; Bollmann, Ulla E

) were so high, that rather professional urban gardening (flower and greenhouses) than handling of biocides from construction materials seem to be able to explain the findings. While the use in agriculture is restricted, the use in greenhouses is currently considered legal in Denmark. Leaching....../partitioning: Considering material properties, it was found out that, for all of the compounds the sorption (and leaching) is highly pH-dependent. It must be take into account that the pH in the porewater of the tested render materials is between 9 and 10 while the rainwater is around 5, thus making prediction difficult...... at this stage. For some of the compounds the sorption is dependent on the amount of polymer in the render, while it is only rarely of importance which polymer is used. Considering the interaction of weather with the leaching of biocides from real walls it turned out that a lot of parameters such as irradiation...

Partial molar volume of proteins studied by the three-dimensional reference interaction site model theory.

Science.gov (United States)

Imai, Takashi; Kovalenko, Andriy; Hirata, Fumio

2005-04-14

The three-dimensional reference interaction site model (3D-RISM) theory is applied to the analysis of hydration effects on the partial molar volume of proteins. For the native structure of some proteins, the partial molar volume is decomposed into geometric and hydration contributions using the 3D-RISM theory combined with the geometric volume calculation. The hydration contributions are correlated with the surface properties of the protein. The thermal volume, which is the volume of voids around the protein induced by the thermal fluctuation of water molecules, is directly proportional to the accessible surface area of the protein. The interaction volume, which is the contribution of electrostatic interactions between the protein and water molecules, is apparently governed by the charged atomic groups on the protein surface. The polar atomic groups do not make any contribution to the interaction volume. The volume differences between low- and high-pressure structures of lysozyme are also analyzed by the present method.

RenderGAN: Generating Realistic Labeled Data

Directory of Open Access Journals (Sweden)

Leon Sixt

2018-06-01

Full Text Available Deep Convolutional Neuronal Networks (DCNNs are showing remarkable performance on many computer vision tasks. Due to their large parameter space, they require many labeled samples when trained in a supervised setting. The costs of annotating data manually can render the use of DCNNs infeasible. We present a novel framework called RenderGAN that can generate large amounts of realistic, labeled images by combining a 3D model and the Generative Adversarial Network framework. In our approach, image augmentations (e.g., lighting, background, and detail are learned from unlabeled data such that the generated images are strikingly realistic while preserving the labels known from the 3D model. We apply the RenderGAN framework to generate images of barcode-like markers that are attached to honeybees. Training a DCNN on data generated by the RenderGAN yields considerably better performance than training it on various baselines.

Physically based rendering from theory to implementation

CERN Document Server

Pharr, Matt

2010-01-01

"Physically Based Rendering, 2nd Edition" describes both the mathematical theory behind a modern photorealistic rendering system as well as its practical implementation. A method - known as 'literate programming'- combines human-readable documentation and source code into a single reference that is specifically designed to aid comprehension. The result is a stunning achievement in graphics education. Through the ideas and software in this book, you will learn to design and employ a full-featured rendering system for creating stunning imagery. This book features new sections on subsurface scattering, Metropolis light transport, precomputed light transport, multispectral rendering, and much more. It includes a companion site complete with source code for the rendering system described in the book, with support for Windows, OS X, and Linux. Code and text are tightly woven together through a unique indexing feature that lists each function, variable, and method on the page that they are first described.

Virtual Whipple: preoperative surgical planning with volume-rendered MDCT images to identify arterial variants relevant to the Whipple procedure.

Science.gov (United States)

Brennan, Darren D; Zamboni, Giulia; Sosna, Jacob; Callery, Mark P; Vollmer, Charles M V; Raptopoulos, Vassilios D; Kruskal, Jonathan B

2007-05-01

The purposes of this study were to combine a thorough understanding of the technical aspects of the Whipple procedure with advanced rendering techniques by introducing a virtual Whipple procedure and to evaluate the utility of this new rendering technique in prediction of the arterial variants that cross the anticipated surgical resection plane. The virtual Whipple is a novel technique that follows the complex surgical steps in a Whipple procedure. Three-dimensional reconstructed angiographic images are used to identify arterial variants for the surgeon as part of the preoperative radiologic assessment of pancreatic and ampullary tumors.

Chromium: A Stress-Processing Framework for Interactive Rendering on Clusters

International Nuclear Information System (INIS)

Humphreys, G.; Houston, M.; Ng, Y.-R.; Frank, R.; Ahern, S.; Kirchner, P.D.; Klosowski, J.T.

2002-01-01

We describe Chromium, a system for manipulating streams of graphics API commands on clusters of workstations. Chromium's stream filters can be arranged to create sort-first and sort-last parallel graphics architectures that, in many cases, support the same applications while using only commodity graphics accelerators. In addition, these stream filters can be extended programmatically, allowing the user to customize the stream transformations performed by nodes in a cluster. Because our stream processing mechanism is completely general, any cluster-parallel rendering algorithm can be either implemented on top of or embedded in Chromium. In this paper, we give examples of real-world applications that use Chromium to achieve good scalability on clusters of workstations, and describe other potential uses of this stream processing technology. By completely abstracting the underlying graphics architecture, network topology, and API command processing semantics, we allow a variety of applications to run in different environments

Detection of Prion Proteins and TSE Infectivity in the Rendering and Biodiesel Manufacture Processes

Energy Technology Data Exchange (ETDEWEB)

Brown, R.; Keller, B.; Oleschuk, R. [Queen' s University, Kingston, Ontario (Canada)

2007-03-15

This paper addresses emerging issues related to monitoring prion proteins and TSE infectivity in the products and waste streams of rendering and biodiesel manufacture processes. Monitoring is critical to addressing the knowledge gaps identified in 'Biodiesel from Specified Risk Material Tallow: An Appraisal of TSE Risks and their Reduction' (IEA's AMF Annex XXX, 2006) that prevent comprehensive risk assessment of TSE infectivity in products and waste. The most important challenge for monitoring TSE risk is the wide variety of sample types, which are generated at different points in the rendering/biodiesel production continuum. Conventional transmissible spongiform encephalopathy (TSE) assays were developed for specified risk material (SRM) and other biological tissues. These, however, are insufficient to address the diverse sample matrices produced in rendering and biodiesel manufacture. This paper examines the sample types expected in rendering and biodiesel manufacture and the implications of applying TSE assay methods to them. The authors then discuss a sample preparation filtration, which has not yet been applied to these sample types, but which has the potential to provide or significantly improve TSE monitoring. The main improvement will come from transfer of the prion proteins from the sample matrix to a matrix compatible with conventional and emerging bioassays. A second improvement will come from preconcentrating the prion proteins, which means transferring proteins from a larger sample volume into a smaller volume for analysis to provide greater detection sensitivity. This filtration method may also be useful for monitoring other samples, including wash waters and other waste streams, which may contain SRM, including those from abattoirs and on-farm operations. Finally, there is a discussion of emerging mass spectrometric methods, which Prusiner and others have shown to be suitable for detection and characterisation of prion proteins (Stahl

Advanced Material Rendering in Blender

Czech Academy of Sciences Publication Activity Database

Hatka, Martin; Haindl, Michal

2012-01-01

Roč. 11, č. 2 (2012), s. 15-23 ISSN 1081-1451 R&D Projects: GA ČR GAP103/11/0335; GA ČR GA102/08/0593 Grant - others:CESNET(CZ) 387/2010; CESNET(CZ) 409/2011 Institutional support: RVO:67985556 Keywords : realistic material rendering * bidirectional texture function * Blender Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2013/RO/haindl-advanced material rendering in blender.pdf

High-quality and interactive animations of 3D time-varying vector fields.

Science.gov (United States)

Helgeland, Anders; Elboth, Thomas

2006-01-01

In this paper, we present an interactive texture-based method for visualizing three-dimensional unsteady vector fields. The visualization method uses a sparse and global representation of the flow, such that it does not suffer from the same perceptual issues as is the case for visualizing dense representations. The animation is made by injecting a collection of particles evenly distributed throughout the physical domain. These particles are then tracked along their path lines. At each time step, these particles are used as seed points to generate field lines using any vector field such as the velocity field or vorticity field. In this way, the animation shows the advection of particles while each frame in the animation shows the instantaneous vector field. In order to maintain a coherent particle density and to avoid clustering as time passes, we have developed a novel particle advection strategy which produces approximately evenly-spaced field lines at each time step. To improve rendering performance, we decouple the rendering stage from the preceding stages of the visualization method. This allows interactive exploration of multiple fields simultaneously, which sets the stage for a more complete analysis of the flow field. The final display is rendered using texture-based direct volume rendering.

RenderSelect: a Cloud Broker Framework for Cloud Renderfarm Services

OpenAIRE

Ruby, Annette J; Aisha, Banu W; Subash, Chandran P

2016-01-01

In the 3D studios the animation scene files undergo a process called as rendering, where the 3D wire frame models are converted into 3D photorealistic images. As the rendering process is both a computationally intensive and a time consuming task, the cloud services based rendering in cloud render farms is gaining popularity among the animators. Though cloud render farms offer many benefits, the animators hesitate to move from their traditional offline rendering to cloud services based render ...

Volumetric ambient occlusion for real-time rendering and games.

Science.gov (United States)

Szirmay-Kalos, L; Umenhoffer, T; Toth, B; Szecsi, L; Sbert, M

2010-01-01

This new algorithm, based on GPUs, can compute ambient occlusion to inexpensively approximate global-illumination effects in real-time systems and games. The first step in deriving this algorithm is to examine how ambient occlusion relates to the physically founded rendering equation. The correspondence stems from a fuzzy membership function that defines what constitutes nearby occlusions. The next step is to develop a method to calculate ambient occlusion in real time without precomputation. The algorithm is based on a novel interpretation of ambient occlusion that measures the relative volume of the visible part of the surface's tangent sphere. The new formula's integrand has low variation and thus can be estimated accurately with a few samples.

Image Based Rendering and Virtual Reality

DEFF Research Database (Denmark)

Livatino, Salvatore

The Presentation concerns with an overview of Image Based Rendering approaches and their use on Virtual Reality, including Virtual Photography and Cinematography, and Mobile Robot Navigation.......The Presentation concerns with an overview of Image Based Rendering approaches and their use on Virtual Reality, including Virtual Photography and Cinematography, and Mobile Robot Navigation....

Earth mortars and earth-lime renders

Directory of Open Access Journals (Sweden)

Maria Fernandes

2008-01-01

Full Text Available Earth surface coatings play a decorative architectural role, apart from their function as wall protection. In Portuguese vernacular architecture, earth mortars were usually applied on stone masonry, while earth renders and plasters were used on indoors surface coatings. Limestone exists only in certain areas of the country and consequently lime was not easily available everywhere, especially on granite and schist regions where stone masonry was a current building technique. In the central west coast of Portugal, the lime slaking procedure entailed slaking the quicklime mixed with earth (sandy soil, in a pit; the resulting mixture would then be combined in a mortar or plaster. This was also the procedure for manufactured adobes stabilized with lime. Adobe buildings with earth-lime renderings and plasters were also traditional in the same region, using lime putty and lime wash for final coat and decoration. Classic decoration on earth architecture from the 18th-19th century was in many countries a consequence of the François Cointeraux (1740-1830 manuals - Les Cahiers d'Architecture Rurale" (1793 - a French guide for earth architecture and building construction. This manual arrived to Portugal in the beginning of XIX century, but was never translated to Portuguese. References about decoration for earth houses were explained on this manual, as well as procedures about earth-lime renders and ornamentation of earth walls; in fact, these procedures are exactly the same as the ones used in adobe buildings in this Portuguese region. The specific purpose of the present paper is to show some cases of earth mortars, renders and plasters on stone buildings in Portugal and to explain the methods of producing earth-lime renders, and also to show some examples of rendering and coating with earth-lime in Portuguese adobe vernacular architecture.

A Calderón multiplicative preconditioner for coupled surface-volume electric field integral equations

KAUST Repository

Bagci, Hakan

2010-08-01

A well-conditioned coupled set of surface (S) and volume (V) electric field integral equations (S-EFIE and V-EFIE) for analyzing wave interactions with densely discretized composite structures is presented. Whereas the V-EFIE operator is well-posed even when applied to densely discretized volumes, a classically formulated S-EFIE operator is ill-posed when applied to densely discretized surfaces. This renders the discretized coupled S-EFIE and V-EFIE system ill-conditioned, and its iterative solution inefficient or even impossible. The proposed scheme regularizes the coupled set of S-EFIE and V-EFIE using a Calderón multiplicative preconditioner (CMP)-based technique. The resulting scheme enables the efficient analysis of electromagnetic interactions with composite structures containing fine/subwavelength geometric features. Numerical examples demonstrate the efficiency of the proposed scheme. © 2006 IEEE.

Leveraging Disturbance Observer Based Torque Control for Improved Impedance Rendering with Series Elastic Actuators

Science.gov (United States)

Mehling, Joshua S.; Holley, James; O'Malley, Marcia K.

2015-01-01

The fidelity with which series elastic actuators (SEAs) render desired impedances is important. Numerous approaches to SEA impedance control have been developed under the premise that high-precision actuator torque control is a prerequisite. Indeed, the design of an inner torque compensator has a significant impact on actuator impedance rendering. The disturbance observer (DOB) based torque control implemented in NASA's Valkyrie robot is considered here and a mathematical model of this torque control, cascaded with an outer impedance compensator, is constructed. While previous work has examined the impact a disturbance observer has on torque control performance, little has been done regarding DOBs and impedance rendering accuracy. Both simulation and a series of experiments are used to demonstrate the significant improvements possible in an SEA's ability to render desired dynamic behaviors when utilizing a DOB. Actuator transparency at low impedances is improved, closed loop hysteresis is reduced, and the actuator's dynamic response to both commands and interaction torques more faithfully matches that of the desired model. All of this is achieved by leveraging DOB based control rather than increasing compensator gains, thus making improved SEA impedance control easier to achieve in practice.

Volume definition system for treatment planning

International Nuclear Information System (INIS)

Alakuijala, Jyrki; Pekkarinen, Ari; Puurunen, Harri

1997-01-01

Purpose: Volume definition is a difficult and time consuming task in 3D treatment planning. We have studied a systems approach for constructing an efficient and reliable set of tools for volume definition. Our intent is to automate body outline, air cavities and bone volume definition and accelerate definition of other anatomical structures. An additional focus is on assisting in definition of CTV and PTV. The primary goals of this work are to cut down the time used in contouring and to improve the accuracy of volume definition. Methods: We used the following tool categories: manual, semi-automatic, automatic, structure management, target volume definition, and visualization tools. The manual tools include mouse contouring tools with contour editing possibilities and painting tools with a scaleable circular brush and an intelligent brush. The intelligent brush adapts its shape to CT value boundaries. The semi-automatic tools consist of edge point chaining, classical 3D region growing of single segment and competitive volume growing of multiple segments. We tuned the volume growing function to take into account both local and global region image values, local volume homogeneity, and distance. Heuristic seeding followed with competitive volume growing finds the body outline, couch and air automatically. The structure management tool stores ICD-O coded structures in a database. The codes have predefined volume growing parameters and thus are able to accommodate the volume growing dissimilarity function for different volume types. The target definition tools include elliptical 3D automargin for CTV to PTV transformation and target volume interpolation and extrapolation by distance transform. Both the CTV and the PTV can overlap with anatomical structures. Visualization tools show the volumes as contours or color wash overlaid on an image and displays voxel rendering or translucent triangle mesh rendering in 3D. Results: The competitive volume growing speeds up the

A parallel coordinates style interface for exploratory volume visualization.

Science.gov (United States)

Tory, Melanie; Potts, Simeon; Möller, Torsten

2005-01-01

We present a user interface, based on parallel coordinates, that facilitates exploration of volume data. By explicitly representing the visualization parameter space, the interface provides an overview of rendering options and enables users to easily explore different parameters. Rendered images are stored in an integrated history bar that facilitates backtracking to previous visualization options. Initial usability testing showed clear agreement between users and experts of various backgrounds (usability, graphic design, volume visualization, and medical physics) that the proposed user interface is a valuable data exploration tool.

3D virtual rendering in thoracoscopic treatment of congenital malformation of the lung

Directory of Open Access Journals (Sweden)

Destro F.

2013-10-01

Full Text Available Introduction: Congenital malformations of the lung (CML are rare but potentially dangerous congenital malformations. Their identification is important in order to define the most appropriate management. Materials and methods: We retrospectively reviewed data from 37 patients affected by CML treated in our Pediatric Surgery Unit in the last four years with minimally invasive surgery (MIS. Results: Prenatal diagnosis was possible in 26/37 patients. Surgery was performed in the first month of life in 3 symptomatic patients and between 6 and 12 months in the others. All patients underwent radiological evaluation prior to thoracoscopic surgery. Images collected were reconstructed using the VR render software. Discussion and conclusions: Volume rendering gives high anatomical resolution and it can be useful to guide the surgical procedure. Thoracoscopy should be the technique of choice because it is safe, effective and feasible. Furthermore it has the benefit of a minimal access technique and it can be easily performed in children.

The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion.

Science.gov (United States)

Guo, Zhi-Jun; Lin, Qiang; Liu, Hai-Tao; Lu, Jun-Ying; Zeng, Yan-Hong; Meng, Fan-Jie; Cao, Bin; Zi, Xue-Rong; Han, Shu-Ming; Zhang, Yu-Huan

2013-09-01

Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring. To explore the feasibility of using 64-slice CT volume-rendering technology to accurately measure pleural fluid volume and to then analyze the correlation between the volume of the free pleural effusion and the different diameters of the pleural effusion. The 64-slice CT volume-rendering technique was used to measure and analyze three parts. First, the fluid volume of a self-made thoracic model was measured and compared with the actual injected volume. Second, the pleural effusion volume was measured before and after pleural fluid drainage in 25 patients, and the volume reduction was compared with the actual volume of the liquid extract. Finally, the free pleural effusion volume was measured in 26 patients to analyze the correlation between it and the diameter of the effusion, which was then used to calculate the regression equation. After using the 64-slice CT volume-rendering technique to measure the fluid volume of the self-made thoracic model, the results were compared with the actual injection volume. No significant differences were found, P = 0.836. For the 25 patients with drained pleural effusions, the comparison of the reduction volume with the actual volume of the liquid extract revealed no significant differences, P = 0.989. The following linear regression equation was used to compare the pleural effusion volume (V) (measured by the CT volume-rendering technique) with the pleural effusion greatest depth (d): V = 158.16 × d - 116.01 (r = 0.91, P = 0.000). The following linear regression was used to compare the volume with the product of the pleural effusion diameters (l × h × d): V = 0.56 × (l × h × d) + 39.44 (r = 0.92, P = 0.000). The 64-slice CT volume-rendering technique can

The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion

International Nuclear Information System (INIS)

Guo, Zhi-Jun; Lin, Qiang; Liu, Hai-Tao

2013-01-01

Background: Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring. Purpose: To explore the feasibility of using 64-slice CT volume-rendering technology to accurately measure pleural fluid volume and to then analyze the correlation between the volume of the free pleural effusion and the different diameters of the pleural effusion. Material and Methods: The 64-slice CT volume-rendering technique was used to measure and analyze three parts. First, the fluid volume of a self-made thoracic model was measured and compared with the actual injected volume. Second, the pleural effusion volume was measured before and after pleural fluid drainage in 25 patients, and the volume reduction was compared with the actual volume of the liquid extract. Finally, the free pleural effusion volume was measured in 26 patients to analyze the correlation between it and the diameter of the effusion, which was then used to calculate the regression equation. Results: After using the 64-slice CT volume-rendering technique to measure the fluid volume of the self-made thoracic model, the results were compared with the actual injection volume. No significant differences were found, P = 0.836. For the 25 patients with drained pleural effusions, the comparison of the reduction volume with the actual volume of the liquid extract revealed no significant differences, P = 0.989. The following linear regression equation was used to compare the pleural effusion volume (V) (measured by the CT volume-rendering technique) with the pleural effusion greatest depth (d): V = 158.16 X d - 116.01 (r = 0.91, P = 0.000). The following linear regression was used to compare the volume with the product of the pleural effusion diameters (l X h X d): V = 0.56 X (l X h X d) + 39.44 (r = 0.92, P = 0

The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion

Energy Technology Data Exchange (ETDEWEB)

Guo, Zhi-Jun [Dept. of Radiology, North China Petroleum Bureau General Hospital, Renqiu, Hebei (China)], e-mail: Gzj3@163.com; Lin, Qiang [Dept. of Oncology, North China Petroleum Bureau General Hospital, Renqiu, Hebei (China); Liu, Hai-Tao [Dept. of General Surgery, North China Petroleum Bureau General Hospital, Renqiu, Hebei (China)] [and others])

2013-09-15

Background: Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring. Purpose: To explore the feasibility of using 64-slice CT volume-rendering technology to accurately measure pleural fluid volume and to then analyze the correlation between the volume of the free pleural effusion and the different diameters of the pleural effusion. Material and Methods: The 64-slice CT volume-rendering technique was used to measure and analyze three parts. First, the fluid volume of a self-made thoracic model was measured and compared with the actual injected volume. Second, the pleural effusion volume was measured before and after pleural fluid drainage in 25 patients, and the volume reduction was compared with the actual volume of the liquid extract. Finally, the free pleural effusion volume was measured in 26 patients to analyze the correlation between it and the diameter of the effusion, which was then used to calculate the regression equation. Results: After using the 64-slice CT volume-rendering technique to measure the fluid volume of the self-made thoracic model, the results were compared with the actual injection volume. No significant differences were found, P = 0.836. For the 25 patients with drained pleural effusions, the comparison of the reduction volume with the actual volume of the liquid extract revealed no significant differences, P = 0.989. The following linear regression equation was used to compare the pleural effusion volume (V) (measured by the CT volume-rendering technique) with the pleural effusion greatest depth (d): V = 158.16 X d - 116.01 (r = 0.91, P = 0.000). The following linear regression was used to compare the volume with the product of the pleural effusion diameters (l X h X d): V = 0.56 X (l X h X d) + 39.44 (r = 0.92, P = 0

One-Dimensional Haptic Rendering Using Audio Speaker with Displacement Determined by Inductance

Directory of Open Access Journals (Sweden)

Avin Khera

2016-03-01

Full Text Available We report overall design considerations and preliminary results for a new haptic rendering device based on an audio loudspeaker. Our application models tissue properties during microsurgery. For example, the device could respond to the tip of a tool by simulating a particular tissue, displaying a desired compressibility and viscosity, giving way as the tissue is disrupted, or exhibiting independent motion, such as that caused by pulsations in blood pressure. Although limited to one degree of freedom and with a relatively small range of displacement compared to other available haptic rendering devices, our design exhibits high bandwidth, low friction, low hysteresis, and low mass. These features are consistent with modeling interactions with delicate tissues during microsurgery. In addition, our haptic rendering device is designed to be simple and inexpensive to manufacture, in part through an innovative method of measuring displacement by existing variations in the speaker’s inductance as the voice coil moves over the permanent magnet. Low latency and jitter are achieved by running the real-time simulation models on a dedicated microprocessor, while maintaining bidirectional communication with a standard laptop computer for user controls and data logging.

Evaluating progressive-rendering algorithms in appearance design tasks.

Science.gov (United States)

Jiawei Ou; Karlik, Ondrej; Křivánek, Jaroslav; Pellacini, Fabio

2013-01-01

Progressive rendering is becoming a popular alternative to precomputational approaches to appearance design. However, progressive algorithms create images exhibiting visual artifacts at early stages. A user study investigated these artifacts' effects on user performance in appearance design tasks. Novice and expert subjects performed lighting and material editing tasks with four algorithms: random path tracing, quasirandom path tracing, progressive photon mapping, and virtual-point-light rendering. Both the novices and experts strongly preferred path tracing to progressive photon mapping and virtual-point-light rendering. None of the participants preferred random path tracing to quasirandom path tracing or vice versa; the same situation held between progressive photon mapping and virtual-point-light rendering. The user workflow didn’t differ significantly with the four algorithms. The Web Extras include a video showing how four progressive-rendering algorithms converged (at http://youtu.be/ck-Gevl1e9s), the source code used, and other supplementary materials.

Moisture movements in render on brick wall

DEFF Research Database (Denmark)

Hansen, Kurt Kielsgaard; Munch, Thomas Astrup; Thorsen, Peter Schjørmann

2003-01-01

A three-layer render on brick wall used for building facades is studied in the laboratory. The vertical render surface is held in contact with water for 24 hours simulating driving rain while it is measured with non-destructive X-ray equipment every hour in order to follow the moisture front...

Value of 3D-Volume Rendering in the Assessment of Coronary Arteries with Retrospectively Ecg-Gated Multislice Spiral CT

International Nuclear Information System (INIS)

Mahnken, A.H.; Wildberger, J.E.; Dedden, K.; Schmitz-Rode, T.; Guenther, R.W.; Sinha, A.M.; Hoffmann, R.; Stanzel, S.

2003-01-01

Purpose: To assess the diagnostic value and measurement precision of 3D volume rendering technique (3D-VRT) from retrospectively ECG-gated multislice spiral CT (MSCT) data sets for imaging of the coronary arteries. Material and Methods: In 35 patients, retrospectively ECG-gated MSCT of the heart using a four detector row MSCT scanner with a standardized examination protocol was performed as well as quantitative X-ray coronary angiography (QCA). The MSCT data was assessed on segmental basis using 3D-VRT exclusively. The coronary artery diameters were measured at the origin of each main coronary branch and 1 cm, 3 cm and 5 cm distally. The minimum, maximum and mean diameters were determined from MSCT angiography and compared to QCA. Results: A total of 353 of 525 (67.2%) coronary artery segments were assessable by MSCT angiography. The proximal segments were more often assessable when compared to the distal segments. Stenoses were detected with a sensitivity of 82.6% and a specificity of 92.8%. According to the Bland-Altman method the mean differences between QCA and MSCT ranged from 0.55 to 1.07 mm with limits of agreement from 2.2 mm to 2.7 mm. Conclusion: When compared to QCA, the ability of 3D-VRT to quantitatively assess coronary artery diameters and coronary artery stenoses is insufficient for clinical purposes

Sketchy Rendering for Information Visualization.

Science.gov (United States)

Wood, J; Isenberg, P; Isenberg, T; Dykes, J; Boukhelifa, N; Slingsby, A

2012-12-01

We present and evaluate a framework for constructing sketchy style information visualizations that mimic data graphics drawn by hand. We provide an alternative renderer for the Processing graphics environment that redefines core drawing primitives including line, polygon and ellipse rendering. These primitives allow higher-level graphical features such as bar charts, line charts, treemaps and node-link diagrams to be drawn in a sketchy style with a specified degree of sketchiness. The framework is designed to be easily integrated into existing visualization implementations with minimal programming modification or design effort. We show examples of use for statistical graphics, conveying spatial imprecision and for enhancing aesthetic and narrative qualities of visualization. We evaluate user perception of sketchiness of areal features through a series of stimulus-response tests in order to assess users' ability to place sketchiness on a ratio scale, and to estimate area. Results suggest relative area judgment is compromised by sketchy rendering and that its influence is dependent on the shape being rendered. They show that degree of sketchiness may be judged on an ordinal scale but that its judgement varies strongly between individuals. We evaluate higher-level impacts of sketchiness through user testing of scenarios that encourage user engagement with data visualization and willingness to critique visualization design. Results suggest that where a visualization is clearly sketchy, engagement may be increased and that attitudes to participating in visualization annotation are more positive. The results of our work have implications for effective information visualization design that go beyond the traditional role of sketching as a tool for prototyping or its use for an indication of general uncertainty.

Interactions of glycine betaine with proteins: insights from volume and compressibility measurements.

Science.gov (United States)

Shek, Yuen Lai; Chalikian, Tigran V

2013-01-29

We report the first application of volume and compressibility measurements to characterization of interactions between cosolvents (osmolytes) and globular proteins. Specifically, we measure the partial molar volumes and adiabatic compressibilities of cytochrome c, ribonuclease A, lysozyme, and ovalbumin in aqueous solutions of the stabilizing osmolyte glycine betaine (GB) at concentrations between 0 and 4 M. The fact that globular proteins do not undergo any conformational transitions in the presence of GB provides an opportunity to study the interactions of GB with proteins in their native states within the entire range of experimentally accessible GB concentrations. We analyze our resulting volumetric data within the framework of a statistical thermodynamic model in which each instance of GB interaction with a protein is viewed as a binding reaction that is accompanied by release of four water molecules. From this analysis, we calculate the association constants, k, as well as changes in volume, ΔV(0), and adiabatic compressibility, ΔK(S0), accompanying each GB-protein association event in an ideal solution. By comparing these parameters with similar characteristics determined for low-molecular weight analogues of proteins, we conclude that there are no significant cooperative effects involved in interactions of GB with any of the proteins studied in this work. We also evaluate the free energies of direct GB-protein interactions. The energetic properties of GB-protein association appear to scale with the size of the protein. For all proteins, the highly favorable change in free energy associated with direct protein-cosolvent interactions is nearly compensated by an unfavorable free energy of cavity formation (excluded volume effect), yielding a modestly unfavorable free energy for the transfer of a protein from water to a GB/water mixture.

[Rendering surgical care to wounded with neck wounds in an armed conflict].

Science.gov (United States)

Samokhvalov, I M; Zavrazhnov, A A; Fakhrutdinov, A M; Sychev, M I

2001-10-01

The results of rendering of the medical care (the first aid, qualified and specialized) obtained in 172 servicemen with neck injuries who stayed in Republic of Chechnya during the period from 09.08.1999 to 28.07.2000 were analyzed. Basing on the results of analysis and experience of casualties' treatment the authors discuss the problems of sequence and volume of surgical care in this group of casualties with reference to available medical evacuation system, surgical tactics at the stage of specialized care. They also consider the peculiarities of operative treatment of the casualties with neck injuries.

Structure-volume relationships: singular volume effects produced by cupric ion-globular protein interaction.

Science.gov (United States)

Katz, S; Shinaberry, G; Heck, E L; Squire, W

1980-08-05

The nature of the volume isotherms produced by the coordination of Cu(II) with ovalbumin and bovine serum albumin differs substantially from the adsorption isotherms produced by these systems. Whereas there was increased binding of Cu(II) associated with a pH increase from pH 5.3 to pH 7.4, the volume isotherms for these systems did not exhibit this type of pH dependence. The volume changes were determined at 30.0 +/- 0.001 degrees C with microdilatometers which could be read to 0.01 muL. The binding isotherms for ovalbumin at pH 5.3 and 7.4 and for bovine serum albumin at pH 5.3 was resolved by a Scatchard plot to yield the appropriate thermodynamic parameters. An algorithm was derived to calculate the distribution of the individual PMi complexes, i.e., PMi-1 + M in equilibrium (Ki) PMi where i equals 1, 2, 3, ..., n moles of cation, M, bound per mole of protein, P, for the above systems. The volume isotherms were then resolved in terms of the constituent delta Vi terms, i.e., the volume change produced by the formation of the individual PMi complexes. These values were verified by an independent graphical differentiation procedure. The coordination of Cu(II) to BSA at pH 7.4 produced a cooperative adsorption isotherm which was not amenable to a Scatchard analysis. The resultant anomalous volume isotherm was resolved into a component related to Cu(II)-site interaction and a negative volume effect attributable to a conformational change induced by complex formation. This structural transition which occurs at physiological pH may constitute a control mechanism for regulating the serum level of Cu(II) and possibly other divalent ions.

Standardized rendering from IR surveillance motion imagery

Science.gov (United States)

Prokoski, F. J.

2014-06-01

Government agencies, including defense and law enforcement, increasingly make use of video from surveillance systems and camera phones owned by non-government entities.Making advanced and standardized motion imaging technology available to private and commercial users at cost-effective prices would benefit all parties. In particular, incorporating thermal infrared into commercial surveillance systems offers substantial benefits beyond night vision capability. Face rendering is a process to facilitate exploitation of thermal infrared surveillance imagery from the general area of a crime scene, to assist investigations with and without cooperating eyewitnesses. Face rendering automatically generates greyscale representations similar to police artist sketches for faces in surveillance imagery collected from proximate locations and times to a crime under investigation. Near-realtime generation of face renderings can provide law enforcement with an investigation tool to assess witness memory and credibility, and integrate reports from multiple eyewitnesses, Renderings can be quickly disseminated through social media to warn of a person who may pose an immediate threat, and to solicit the public's help in identifying possible suspects and witnesses. Renderings are pose-standardized so as to not divulge the presence and location of eyewitnesses and surveillance cameras. Incorporation of thermal infrared imaging into commercial surveillance systems will significantly improve system performance, and reduce manual review times, at an incremental cost that will continue to decrease. Benefits to criminal justice would include improved reliability of eyewitness testimony and improved accuracy of distinguishing among minority groups in eyewitness and surveillance identifications.

GPU Pro 5 advanced rendering techniques

CERN Document Server

Engel, Wolfgang

2014-01-01

In GPU Pro5: Advanced Rendering Techniques, section editors Wolfgang Engel, Christopher Oat, Carsten Dachsbacher, Michal Valient, Wessam Bahnassi, and Marius Bjorge have once again assembled a high-quality collection of cutting-edge techniques for advanced graphics processing unit (GPU) programming. Divided into six sections, the book covers rendering, lighting, effects in image space, mobile devices, 3D engine design, and compute. It explores rasterization of liquids, ray tracing of art assets that would otherwise be used in a rasterized engine, physically based area lights, volumetric light

Innovative Lime Pozzolana Renders for Reconstruction of Historical Buildings

International Nuclear Information System (INIS)

Vejmelkova, E.; Maca, P.; Konvalinka, P.; Cerny, R.

2011-01-01

Bulk density, matrix density, open porosity, compressive strength, bending strength, water sorptivity, moisture diffusivity, water vapor diffusion coefficient, thermal conductivity, specific heat capacity and thermal diffusivity of two innovative renovation renders on limepozzolana basis are analyzed. The obtained results are compared with reference lime plaster and two commercial renovation renders, and conclusions on the applicability of the particular renders in practical reconstruction works are drawn. (author)

The rendering context for stereoscopic 3D web

Science.gov (United States)

Chen, Qinshui; Wang, Wenmin; Wang, Ronggang

2014-03-01

3D technologies on the Web has been studied for many years, but they are basically monoscopic 3D. With the stereoscopic technology gradually maturing, we are researching to integrate the binocular 3D technology into the Web, creating a stereoscopic 3D browser that will provide users with a brand new experience of human-computer interaction. In this paper, we propose a novel approach to apply stereoscopy technologies to the CSS3 3D Transforms. Under our model, each element can create or participate in a stereoscopic 3D rendering context, in which 3D Transforms such as scaling, translation and rotation, can be applied and be perceived in a truly 3D space. We first discuss the underlying principles of stereoscopy. After that we discuss how these principles can be applied to the Web. A stereoscopic 3D browser with backward compatibility is also created for demonstration purposes. We take advantage of the open-source WebKit project, integrating the 3D display ability into the rendering engine of the web browser. For each 3D web page, our 3D browser will create two slightly different images, each representing the left-eye view and right-eye view, both to be combined on the 3D display to generate the illusion of depth. And as the result turns out, elements can be manipulated in a truly 3D space.

Value of three-dimensional volume rendering images in the assessment of the centrality index for preoperative planning in patients with renal masses.

Science.gov (United States)

Sofia, C; Magno, C; Silipigni, S; Cantisani, V; Mucciardi, G; Sottile, F; Inferrera, A; Mazziotti, S; Ascenti, G

2017-01-01

To evaluate the precision of the centrality index (CI) measurement on three-dimensional (3D) volume rendering technique (VRT) images in patients with renal masses, compared to its standard measurement on axial images. Sixty-five patients with renal lesions underwent contrast-enhanced multidetector (MD) computed tomography (CT) for preoperative imaging. Two readers calculated the CI on two-dimensional axial images and on VRT images, measuring it in the plane that the tumour and centre of the kidney were lying in. Correlation and agreement of interobserver measurements and inter-method results were calculated using intraclass correlation (ICC) coefficients and the Bland-Altman method. Time saving was also calculated. The correlation coefficients were r=0.99 (ppresent study showed that VRT and axial images produce almost identical values of CI, with the advantages of greater ease of execution and a time saving of almost 50% for 3D VRT images. In addition, VRT provides an integrated perspective that can better assist surgeons in clinical decision making and in operative planning, suggesting this technique as a possible standard method for CI measurement. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

An image-based approach to the rendering of crowds in real-time

OpenAIRE

Tecchia, Franco

2007-01-01

The wide use of computer graphics in games, entertainment, medical, architectural and cultural applications, has led it to becoming a prevalent area of research. Games and entertainment in general have become one of the driving forces of the real-time computer graphics industry, bringing reasonably realistic, complex and appealing virtual worlds to the mass-market. At the current stage of technology, an user can interactively navigate through complex, polygon-based scenes rendered with sophis...

Coil–globule transition of a polymer involved in excluded-volume interactions with macromolecules

International Nuclear Information System (INIS)

Odagiri, Kenta; Seki, Kazuhiko

2015-01-01

Polymers adopt extended coil and compact globule states according to the balance between entropy and interaction energies. The transition of a polymer between an extended coil state and compact globule state can be induced by changing thermodynamic force such as temperature to alter the energy/entropy balance. Previously, this transition was theoretically studied by taking into account the excluded-volume interaction between monomers of a polymer chain using the partition function. For binary mixtures of a long polymer and short polymers, the coil-globule transition can be induced by changing the concentration of the shorter polymers. Here, we investigate the transition caused by short polymers by generalizing the partition function of the long polymer to include the excluded-volume effect of short polymers. The coil-globule transition is studied as a function of the concentration of mixed polymers by systematically varying Flory’s χ-parameters. We show that the transition is caused by the interplay between the excluded-volume interaction and the dispersion state of short polymers in the solvent. We also reveal that the same results can be obtained by combining the mixing entropy and elastic energy if the volume of a long polymer is properly defined

Validation of a colour rendering index based on memory colours

OpenAIRE

Smet, Kevin; Jost-Boissard, Sophie; Ryckaert, Wouter; Deconinck, Geert; Hanselaer, Peter

2010-01-01

In this paper the performance of a colour rendering index based on memory colours is investigated in comparison with the current CIE Colour Rendering Index, the NIST Colour Quality Scale and visual appreciation results obtained at CNRS at Lyon University for a set of 3000K and 4000K LED light sources. The Pearson and Spearman correlation coefficients between each colour rendering metric and the two sets of visual results were calculated. It was found that the memory colour based colour render...

Media Presentation Synchronisation for Non-monolithic Rendering Architectures

NARCIS (Netherlands)

I. Vaishnavi (Ishan); D.C.A. Bulterman (Dick); P.S. Cesar Garcia (Pablo Santiago); B. Gao (Bo)

2007-01-01

htmlabstractNon-monolithic renderers are physically distributed media playback engines. Non-monolithic renderers may use a number of different underlying network connection types to transmit media items belonging to a presentation. There is therefore a need for a media based and inter-network- type

Single minimum incision endoscopic radical nephrectomy for renal tumors with preoperative virtual navigation using 3D-CT volume-rendering

Directory of Open Access Journals (Sweden)

Shioyama Yasukazu

2010-04-01

Full Text Available Abstract Background Single minimum incision endoscopic surgery (MIES involves the use of a flexible high-definition laparoscope to facilitate open surgery. We reviewed our method of radical nephrectomy for renal tumors, which is single MIES combined with preoperative virtual surgery employing three-dimensional CT images reconstructed by the volume rendering method (3D-CT images in order to safely and appropriately approach the renal hilar vessels. We also assessed the usefulness of 3D-CT images. Methods Radical nephrectomy was done by single MIES via the translumbar approach in 80 consecutive patients. We performed the initial 20 MIES nephrectomies without preoperative 3D-CT images and the subsequent 60 MIES nephrectomies with preoperative 3D-CT images for evaluation of the renal hilar vessels and the relation of each tumor to the surrounding structures. On the basis of the 3D information, preoperative virtual surgery was performed with a computer. Results Single MIES nephrectomy was successful in all patients. In the 60 patients who underwent 3D-CT, the number of renal arteries and veins corresponded exactly with the preoperative 3D-CT data (100% sensitivity and 100% specificity. These 60 nephrectomies were completed with a shorter operating time and smaller blood loss than the initial 20 nephrectomies. Conclusions Single MIES radical nephrectomy combined with 3D-CT and virtual surgery achieved a shorter operating time and less blood loss, possibly due to safer and easier handling of the renal hilar vessels.

Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

Energy Technology Data Exchange (ETDEWEB)

Wong, S.T.C. [Univ. of California, San Francisco, CA (United States)

1997-02-01

The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a {open_quotes}true 3D screen{close_quotes}. To confine the scope, this presentation will not discuss such approaches.

Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

International Nuclear Information System (INIS)

Wong, S.T.C.

1997-01-01

The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a open-quotes true 3D screenclose quotes. To confine the scope, this presentation will not discuss such approaches

Extreme simplification and rendering of point sets using algebraic multigrid

NARCIS (Netherlands)

Reniers, D.; Telea, A.C.

2009-01-01

We present a novel approach for extreme simplification of point set models, in the context of real-time rendering. Point sets are often rendered using simple point primitives, such as oriented discs. However, this requires using many primitives to render even moderately simple shapes. Often, one

Screen-Space Normal Distribution Function Caching for Consistent Multi-Resolution Rendering of Large Particle Data

KAUST Repository

Ibrahim, Mohamed

2017-08-28

Molecular dynamics (MD) simulations are crucial to investigating important processes in physics and thermodynamics. The simulated atoms are usually visualized as hard spheres with Phong shading, where individual particles and their local density can be perceived well in close-up views. However, for large-scale simulations with 10 million particles or more, the visualization of large fields-of-view usually suffers from strong aliasing artifacts, because the mismatch between data size and output resolution leads to severe under-sampling of the geometry. Excessive super-sampling can alleviate this problem, but is prohibitively expensive. This paper presents a novel visualization method for large-scale particle data that addresses aliasing while enabling interactive high-quality rendering. We introduce the novel concept of screen-space normal distribution functions (S-NDFs) for particle data. S-NDFs represent the distribution of surface normals that map to a given pixel in screen space, which enables high-quality re-lighting without re-rendering particles. In order to facilitate interactive zooming, we cache S-NDFs in a screen-space mipmap (S-MIP). Together, these two concepts enable interactive, scale-consistent re-lighting and shading changes, as well as zooming, without having to re-sample the particle data. We show how our method facilitates the interactive exploration of real-world large-scale MD simulation data in different scenarios.

Screen-Space Normal Distribution Function Caching for Consistent Multi-Resolution Rendering of Large Particle Data

KAUST Repository

Ibrahim, Mohamed; Wickenhauser, Patrick; Rautek, Peter; Reina, Guido; Hadwiger, Markus

2017-01-01

Molecular dynamics (MD) simulations are crucial to investigating important processes in physics and thermodynamics. The simulated atoms are usually visualized as hard spheres with Phong shading, where individual particles and their local density can be perceived well in close-up views. However, for large-scale simulations with 10 million particles or more, the visualization of large fields-of-view usually suffers from strong aliasing artifacts, because the mismatch between data size and output resolution leads to severe under-sampling of the geometry. Excessive super-sampling can alleviate this problem, but is prohibitively expensive. This paper presents a novel visualization method for large-scale particle data that addresses aliasing while enabling interactive high-quality rendering. We introduce the novel concept of screen-space normal distribution functions (S-NDFs) for particle data. S-NDFs represent the distribution of surface normals that map to a given pixel in screen space, which enables high-quality re-lighting without re-rendering particles. In order to facilitate interactive zooming, we cache S-NDFs in a screen-space mipmap (S-MIP). Together, these two concepts enable interactive, scale-consistent re-lighting and shading changes, as well as zooming, without having to re-sample the particle data. We show how our method facilitates the interactive exploration of real-world large-scale MD simulation data in different scenarios.

Interactive visualization of APT data at full fidelity

International Nuclear Information System (INIS)

Bryden, Aaron; Broderick, Scott; Suram, Santosh K.; Kaluskar, Kaustubh; LeSar, Richard; Rajan, Krishna

2013-01-01

Understanding the impact of noise and incomplete data is a critical need for using atom probe tomography effectively. Although many tools and techniques have been developed to address this problem, visualization of the raw data remains an important part of this process. In this paper, we present two contributions to the visualization of data acquired through atom probe tomography. First, we describe the application of a rendering technique, ray-cast spherical impostors, that enables the interactive rendering of large numbers (as large as 10 million plus) of pixel perfect, lit spheres representing individual atoms. This technique is made possible by the use of a consumer-level graphics processing unit (GPU), and it yields an order of magnitude improvement both in render quality and speed over techniques previously used to render spherical glyphs in this domain. Second, we present an interactive tool that allows the user to mask, filter, and colorize the data in real time to help them understand and visualize a precise subset and properties of the raw data. We demonstrate the effectiveness of our tool through benchmarks and an example that shows how the ability to interactively render large numbers of spheres, combined with the use of filters and masks, leads to improved understanding of the three-dimensional (3D) and incomplete nature of atom probe data. This improvement arises from the ability of lit spheres to more effectively show the 3D position and the local spatial distribution of individual atoms than what is possible with point or isosurface renderings. The techniques described in this paper serve to introduce new rendering and interaction techniques that have only recently become practical as well as new ways of interactively exploring the raw data. - Highlights: ► Application of spherical impostor rendering to atom probe data visualization. ► Presented an interactive tool for visualizing atom probe tomography data. ► Presented a comparison of

A Real-Time Sound Field Rendering Processor

Directory of Open Access Journals (Sweden)

Tan Yiyu

2017-12-01

Full Text Available Real-time sound field renderings are computationally intensive and memory-intensive. Traditional rendering systems based on computer simulations suffer from memory bandwidth and arithmetic units. The computation is time-consuming, and the sample rate of the output sound is low because of the long computation time at each time step. In this work, a processor with a hybrid architecture is proposed to speed up computation and improve the sample rate of the output sound, and an interface is developed for system scalability through simply cascading many chips to enlarge the simulated area. To render a three-minute Beethoven wave sound in a small shoe-box room with dimensions of 1.28 m × 1.28 m × 0.64 m, the field programming gate array (FPGA-based prototype machine with the proposed architecture carries out the sound rendering at run-time while the software simulation with the OpenMP parallelization takes about 12.70 min on a personal computer (PC with 32 GB random access memory (RAM and an Intel i7-6800K six-core processor running at 3.4 GHz. The throughput in the software simulation is about 194 M grids/s while it is 51.2 G grids/s in the prototype machine even if the clock frequency of the prototype machine is much lower than that of the PC. The rendering processor with a processing element (PE and interfaces consumes about 238,515 gates after fabricated by the 0.18 µm processing technology from the ROHM semiconductor Co., Ltd. (Kyoto Japan, and the power consumption is about 143.8 mW.

Simplification of Visual Rendering in Simulated Prosthetic Vision Facilitates Navigation.

Science.gov (United States)

Vergnieux, Victor; Macé, Marc J-M; Jouffrais, Christophe

2017-09-01

Visual neuroprostheses are still limited and simulated prosthetic vision (SPV) is used to evaluate potential and forthcoming functionality of these implants. SPV has been used to evaluate the minimum requirement on visual neuroprosthetic characteristics to restore various functions such as reading, objects and face recognition, object grasping, etc. Some of these studies focused on obstacle avoidance but only a few investigated orientation or navigation abilities with prosthetic vision. The resolution of current arrays of electrodes is not sufficient to allow navigation tasks without additional processing of the visual input. In this study, we simulated a low resolution array (15 × 18 electrodes, similar to a forthcoming generation of arrays) and evaluated the navigation abilities restored when visual information was processed with various computer vision algorithms to enhance the visual rendering. Three main visual rendering strategies were compared to a control rendering in a wayfinding task within an unknown environment. The control rendering corresponded to a resizing of the original image onto the electrode array size, according to the average brightness of the pixels. In the first rendering strategy, vision distance was limited to 3, 6, or 9 m, respectively. In the second strategy, the rendering was not based on the brightness of the image pixels, but on the distance between the user and the elements in the field of view. In the last rendering strategy, only the edges of the environments were displayed, similar to a wireframe rendering. All the tested renderings, except the 3 m limitation of the viewing distance, improved navigation performance and decreased cognitive load. Interestingly, the distance-based and wireframe renderings also improved the cognitive mapping of the unknown environment. These results show that low resolution implants are usable for wayfinding if specific computer vision algorithms are used to select and display appropriate

Blender cycles lighting and rendering cookbook

CERN Document Server

Iraci, Bernardo

2013-01-01

An in-depth guide full of step-by-step recipes to explore the concepts behind the usage of Cycles. Packed with illustrations, and lots of tips and tricks; the easy-to-understand nature of the book will help the reader understand even the most complex concepts with ease.If you are a digital artist who already knows your way around Blender, and you want to learn about the new Cycles' rendering engine, this is the book for you. Even experts will be able to pick up new tips and tricks to make the most of the rendering capabilities of Cycles.

Real-Time Location-Based Rendering of Urban Underground Pipelines

Directory of Open Access Journals (Sweden)

Wei Li

2018-01-01

Full Text Available The concealment and complex spatial relationships of urban underground pipelines present challenges in managing them. Recently, augmented reality (AR has been a hot topic around the world, because it can enhance our perception of reality by overlaying information about the environment and its objects onto the real world. Using AR, underground pipelines can be displayed accurately, intuitively, and in real time. We analyzed the characteristics of AR and their application in underground pipeline management. We mainly focused on the AR pipeline rendering procedure based on the BeiDou Navigation Satellite System (BDS and simultaneous localization and mapping (SLAM technology. First, in aiming to improve the spatial accuracy of pipeline rendering, we used differential corrections received from the Ground-Based Augmentation System to compute the precise coordinates of users in real time, which helped us accurately retrieve and draw pipelines near the users, and by scene recognition the accuracy can be further improved. Second, in terms of pipeline rendering, we used Visual-Inertial Odometry (VIO to track the rendered objects and made some improvements to visual effects, which can provide steady dynamic tracking of pipelines even in relatively markerless environments and outdoors. Finally, we used the occlusion method based on real-time 3D reconstruction to realistically express the immersion effect of underground pipelines. We compared our methods to the existing methods and concluded that the method proposed in this research improves the spatial accuracy of pipeline rendering and the portability of the equipment. Moreover, the updating of our rendering procedure corresponded with the moving of the user’s location, thus we achieved a dynamic rendering of pipelines in the real environment.

3D cinematic rendering of the calvarium, maxillofacial structures, and skull base: preliminary observations.

Science.gov (United States)

Rowe, Steven P; Zinreich, S James; Fishman, Elliot K

2018-06-01

Three-dimensional (3D) visualizations of volumetric data from CT have gained widespread clinical acceptance and are an important method for evaluating complex anatomy and pathology. Recently, cinematic rendering (CR), a new 3D visualization methodology, has become available. CR utilizes a lighting model that allows for the production of photorealistic images from isotropic voxel data. Given how new this technique is, studies to evaluate its clinical utility and any potential advantages or disadvantages relative to other 3D methods such as volume rendering have yet to be published. In this pictorial review, we provide examples of normal calvarial, maxillofacial, and skull base anatomy and pathological conditions that highlight the potential for CR images to aid in patient evaluation and treatment planning. The highly detailed images and nuanced shadowing that are intrinsic to CR are well suited to the display of the complex anatomy in this region of the body. We look forward to studies with CR that will ascertain the ultimate value of this methodology to evaluate calvarium, maxillofacial, and skull base morphology as well as other complex anatomic structures.

Particle-based non-photorealistic volume visualization

NARCIS (Netherlands)

Busking, S.; Vilanova, A.; Van Wijk, J.J.

2007-01-01

Non-photorealistic techniques are usually applied to produce stylistic renderings. In visualization, these techniques are often able to simplify data, producing clearer images than traditional visualization methods. We investigate the use of particle systems for visualizing volume datasets using

Particle-based non-photorealistic volume visualization

NARCIS (Netherlands)

Busking, S.; Vilanova, A.; Wijk, van J.J.

2008-01-01

Non-photorealistic techniques are usually applied to produce stylistic renderings. In visualization, these techniques are often able to simplify data, producing clearer images than traditional visualization methods. We investigate the use of particle systems for visualizing volume datasets using

High-fidelity haptic and visual rendering for patient-specific simulation of temporal bone surgery.

Science.gov (United States)

Chan, Sonny; Li, Peter; Locketz, Garrett; Salisbury, Kenneth; Blevins, Nikolas H

2016-12-01

Medical imaging techniques provide a wealth of information for surgical preparation, but it is still often the case that surgeons are examining three-dimensional pre-operative image data as a series of two-dimensional images. With recent advances in visual computing and interactive technologies, there is much opportunity to provide surgeons an ability to actively manipulate and interpret digital image data in a surgically meaningful way. This article describes the design and initial evaluation of a virtual surgical environment that supports patient-specific simulation of temporal bone surgery using pre-operative medical image data. Computational methods are presented that enable six degree-of-freedom haptic feedback during manipulation, and that simulate virtual dissection according to the mechanical principles of orthogonal cutting and abrasive wear. A highly efficient direct volume renderer simultaneously provides high-fidelity visual feedback during surgical manipulation of the virtual anatomy. The resulting virtual surgical environment was assessed by evaluating its ability to replicate findings in the operating room, using pre-operative imaging of the same patient. Correspondences between surgical exposure, anatomical features, and the locations of pathology were readily observed when comparing intra-operative video with the simulation, indicating the predictive ability of the virtual surgical environment.

Transfer function design based on user selected samples for intuitive multivariate volume exploration

KAUST Repository

Zhou, Liang

2013-02-01

Multivariate volumetric datasets are important to both science and medicine. We propose a transfer function (TF) design approach based on user selected samples in the spatial domain to make multivariate volumetric data visualization more accessible for domain users. Specifically, the user starts the visualization by probing features of interest on slices and the data values are instantly queried by user selection. The queried sample values are then used to automatically and robustly generate high dimensional transfer functions (HDTFs) via kernel density estimation (KDE). Alternatively, 2D Gaussian TFs can be automatically generated in the dimensionality reduced space using these samples. With the extracted features rendered in the volume rendering view, the user can further refine these features using segmentation brushes. Interactivity is achieved in our system and different views are tightly linked. Use cases show that our system has been successfully applied for simulation and complicated seismic data sets. © 2013 IEEE.

Transfer function design based on user selected samples for intuitive multivariate volume exploration

KAUST Repository

Zhou, Liang; Hansen, Charles

2013-01-01

Multivariate volumetric datasets are important to both science and medicine. We propose a transfer function (TF) design approach based on user selected samples in the spatial domain to make multivariate volumetric data visualization more accessible for domain users. Specifically, the user starts the visualization by probing features of interest on slices and the data values are instantly queried by user selection. The queried sample values are then used to automatically and robustly generate high dimensional transfer functions (HDTFs) via kernel density estimation (KDE). Alternatively, 2D Gaussian TFs can be automatically generated in the dimensionality reduced space using these samples. With the extracted features rendered in the volume rendering view, the user can further refine these features using segmentation brushes. Interactivity is achieved in our system and different views are tightly linked. Use cases show that our system has been successfully applied for simulation and complicated seismic data sets. © 2013 IEEE.

Emission of VOC's from modified rendering process

International Nuclear Information System (INIS)

Bhatti, Z.A.; Raja, I.A.; Saddique, M.; Langenhove, H.V.

2005-01-01

Rendering technique for processing of dead animal and slaughterhouse wastes into valuable products. It involves cooking of raw material and later Sterilization was added to reduce the Bovine Spongiform Encephalopathy (BSE). Studies have been carried out on rendering emission, with the normal cooking process. Our study shows, that the sterilization step in rendering process increases the emission of volatile organic compounds (VOC's). Gas samples, containing VOC's, were analyzed by the GC/MS (Gas Chromatograph and Mass Spectrometry). The most important groups of compounds- alcohols and cyclic hydrocarbons were identified. In the group of alcohol; 1-butanol, l-pentanol and l-hexanol compounds were found while in the group of cyclic hydrocarbon; methyl cyclopentane and cyclohexane compounds were detected. Other groups like aldehyde, sulphur containing compounds, ketone and furan were also found. Some compounds, like l-pentanol, 2-methyl propanal, dimethyl disulfide and dimethyl trisulfide, which belong to these groups, cause malodor. It is important to know these compounds to treat odorous gasses. (author)

Continuous Surface Rendering, Passing from CAD to Physical Representation

Directory of Open Access Journals (Sweden)

Mario Covarrubias

2013-06-01

Full Text Available This paper describes a desktop-mechatronic interface that has been conceived to support designers in the evaluation of aesthetic virtual shapes. This device allows a continuous and smooth free hand contact interaction on a real and developable plastic tape actuated by a servo-controlled mechanism. The objective in designing this device is to reproduce a virtual surface with a consistent physical rendering well adapted to designers' needs. The desktop-mechatronic interface consists in a servo-actuated plastic strip that has been devised and implemented using seven interpolation points. In fact, by using the MEC (Minimal Energy Curve Spline approach, a developable real surface is rendered taking into account the CAD geometry of the virtual shapes. In this paper, we describe the working principles of the interface by using both absolute and relative approaches to control the position on each single control point on the MEC spline. Then, we describe the methodology that has been implemented, passing from the CAD geometry, linked to VisualNastran in order to maintain the parametric properties of the virtual shape. Then, we present the co-simulation between VisualNastran and MATLAB/Simulink used for achieving this goal and controlling the system and finally, we present the results of the subsequent testing session specifically carried out to evaluate the accuracy and the effectiveness of the mechatronic device.

A kinesthetic washout filter for force-feedback rendering.

Science.gov (United States)

Danieau, Fabien; Lecuyer, Anatole; Guillotel, Philippe; Fleureau, Julien; Mollet, Nicolas; Christie, Marc

2015-01-01

Today haptic feedback can be designed and associated to audiovisual content (haptic-audiovisuals or HAV). Although there are multiple means to create individual haptic effects, the issue of how to properly adapt such effects on force-feedback devices has not been addressed and is mostly a manual endeavor. We propose a new approach for the haptic rendering of HAV, based on a washout filter for force-feedback devices. A body model and an inverse kinematics algorithm simulate the user's kinesthetic perception. Then, the haptic rendering is adapted in order to handle transitions between haptic effects and to optimize the amplitude of effects regarding the device capabilities. Results of a user study show that this new haptic rendering can successfully improve the HAV experience.

Processing-in-Memory Enabled Graphics Processors for 3D Rendering

Energy Technology Data Exchange (ETDEWEB)

Xie, Chenhao; Song, Shuaiwen; Wang, Jing; Zhang, Weigong; Fu, Xin

2017-02-06

The performance of 3D rendering of Graphics Processing Unit that convents 3D vector stream into 2D frame with 3D image effects significantly impact users’ gaming experience on modern computer systems. Due to the high texture throughput in 3D rendering, main memory bandwidth becomes a critical obstacle for improving the overall rendering performance. 3D stacked memory systems such as Hybrid Memory Cube (HMC) provide opportunities to significantly overcome the memory wall by directly connecting logic controllers to DRAM dies. Based on the observation that texel fetches significantly impact off-chip memory traffic, we propose two architectural designs to enable Processing-In-Memory based GPU for efficient 3D rendering.

RAY TRACING RENDER MENGGUNAKAN FRAGMENT ANTI ALIASING

Directory of Open Access Journals (Sweden)

Febriliyan Samopa

2008-07-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Rendering is generating surface and three-dimensional effects on an object displayed on a monitor screen. Ray tracing as a rendering method that traces ray for each image pixel has a drawback, that is, aliasing (jaggies effect. There are some methods for executing anti aliasing. One of those methods is OGSS (Ordered Grid Super Sampling. OGSS is able to perform aliasing well. However, this method requires more computation time since sampling of all pixels in the image will be increased. Fragment Anti Aliasing (FAA is a new alternative method that can cope with the drawback. FAA will check the image when performing rendering to a scene. Jaggies effect is only happened at curve and gradient object. Therefore, only this part of object that will experience sampling magnification. After this sampling magnification and the pixel values are computed, then downsample is performed to retrieve the original pixel values. Experimental results show that the software can implement ray tracing well in order to form images, and it can implement FAA and OGSS technique to perform anti aliasing. In general, rendering using FAA is faster than using OGSS

Rendering potential wearable robot designs with the LOPES gait trainer.

Science.gov (United States)

Koopman, B; van Asseldonk, E H F; van der Kooij, H; van Dijk, W; Ronsse, R

2011-01-01

In recent years, wearable robots (WRs) for rehabilitation, personal assistance, or human augmentation are gaining increasing interest. To make these devices more energy efficient, radical changes to the mechanical structure of the device are being considered. However, it remains very difficult to predict how people will respond to, and interact with, WRs that differ in terms of mechanical design. Users may adjust their gait pattern in response to the mechanical restrictions or properties of the device. The goal of this pilot study is to show the feasibility of rendering the mechanical properties of different potential WR designs using the robotic gait training device LOPES. This paper describes a new method that selectively cancels the dynamics of LOPES itself and adds the dynamics of the rendered WR using two parallel inverse models. Adaptive frequency oscillators were used to get estimates of the joint position, velocity, and acceleration. Using the inverse models, different WR designs can be evaluated, eliminating the need to build several prototypes. As a proof of principle, we simulated the effect of a very simple WR that consisted of a mass attached to the ankles. Preliminary results show that we are partially able to cancel the dynamics of LOPES. Additionally, the simulation of the mass showed an increase in muscle activity but not in the same level as during the control, where subjects actually carried the mass. In conclusion, the results in this paper suggest that LOPES can be used to render different WRs. In addition, it is very likely that the results can be further optimized when more effort is put in retrieving proper estimations for the velocity and acceleration, which are required for the inverse models. © 2011 IEEE

Digital color acquisition, perception, coding and rendering

CERN Document Server

Fernandez-Maloigne, Christine; Macaire, Ludovic

2013-01-01

In this book the authors identify the basic concepts and recent advances in the acquisition, perception, coding and rendering of color. The fundamental aspects related to the science of colorimetry in relation to physiology (the human visual system) are addressed, as are constancy and color appearance. It also addresses the more technical aspects related to sensors and the color management screen. Particular attention is paid to the notion of color rendering in computer graphics. Beyond color, the authors also look at coding, compression, protection and quality of color images and videos.

Semantics by analogy for illustrative volume visualization☆

Science.gov (United States)

Gerl, Moritz; Rautek, Peter; Isenberg, Tobias; Gröller, Eduard

2012-01-01

We present an interactive graphical approach for the explicit specification of semantics for volume visualization. This explicit and graphical specification of semantics for volumetric features allows us to visually assign meaning to both input and output parameters of the visualization mapping. This is in contrast to the implicit way of specifying semantics using transfer functions. In particular, we demonstrate how to realize a dynamic specification of semantics which allows to flexibly explore a wide range of mappings. Our approach is based on three concepts. First, we use semantic shader augmentation to automatically add rule-based rendering functionality to static visualization mappings in a shader program, while preserving the visual abstraction that the initial shader encodes. With this technique we extend recent developments that define a mapping between data attributes and visual attributes with rules, which are evaluated using fuzzy logic. Second, we let users define the semantics by analogy through brushing on renderings of the data attributes of interest. Third, the rules are specified graphically in an interface that provides visual clues for potential modifications. Together, the presented methods offer a high degree of freedom in the specification and exploration of rule-based mappings and avoid the limitations of a linguistic rule formulation. PMID:23576827

A volume-filtered formulation to capture particle-shock interactions in multiphase compressible flows

Science.gov (United States)

Shallcross, Gregory; Capecelatro, Jesse

2017-11-01

Compressible particle-laden flows are common in engineering systems. Applications include but are not limited to water injection in high-speed jet flows for noise suppression, rocket-plume surface interactions during planetary landing, and explosions during coal mining operations. Numerically, it is challenging to capture these interactions due to the wide range of length and time scales. Additionally, there are many forms of the multiphase compressible flow equations with volume fraction effects, some of which are conflicting in nature. The purpose of this presentation is to develop the capability to accurately capture particle-shock interactions in systems with a large number of particles from dense to dilute regimes. A thorough derivation of the volume filtered equations is presented. The volume filtered equations are then implemented in a high-order, energy-stable Eulerian-Lagrangian framework. We show this framework is capable of decoupling the fluid mesh from the particle size, enabling arbitrary particle size distributions in the presence of shocks. The proposed method is then assessed against particle-laden shock tube data. Quantities of interest include fluid-phase pressure profiles and particle spreading rates. The effect of collisions in 2D and 3D are also evaluated.

Non-Photorealistic Rendering in Chinese Painting of Animals

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

A set of algorithms is proposed in this paper to automatically transform 3D animal models to Chinese painting style. Inspired by real painting process in Chinese painting of animals, we divide the whole rendering process into two parts: borderline stroke making and interior shading. In borderline stroke making process we first find 3D model silhouettes in real-time depending on the viewing direction of a user. After retrieving silhouette information from all model edges, a stroke linking mechanism is applied to link these independent edges into a long stroke. Finally we grow a plain thin silhouette line to a stylus stroke with various widths at each control point and a 2D brush model is combined with it to simulate a Chinese painting stroke. In the interior shading pipeline, three stages are used to convert a Gouraud-shading image to a Chinese painting style image: color quantization, ink diffusion and box filtering. The color quantization stage assigns all pixels in an image into four color levels and each level represents a color layer in a Chinese painting. Ink diffusion stage is used to transfer inks and water between different levels and to grow areas in an irregular way. The box filtering stage blurs sharp borders between different levels to embellish the appearance of final interior shading image. In addition to automatic rendering, an interactive Chinese painting system which is equipped with friendly input devices can be also combined to generate more artistic Chinese painting images manually.

A new strategic neurosurgical planning tool for brainstem cavernous malformations using interactive computer graphics with multimodal fusion images.

Science.gov (United States)

Kin, Taichi; Nakatomi, Hirofumi; Shojima, Masaaki; Tanaka, Minoru; Ino, Kenji; Mori, Harushi; Kunimatsu, Akira; Oyama, Hiroshi; Saito, Nobuhito

2012-07-01

In this study, the authors used preoperative simulation employing 3D computer graphics (interactive computer graphics) to fuse all imaging data for brainstem cavernous malformations. The authors evaluated whether interactive computer graphics or 2D imaging correlated better with the actual operative field, particularly in identifying a developmental venous anomaly (DVA). The study population consisted of 10 patients scheduled for surgical treatment of brainstem cavernous malformations. Data from preoperative imaging (MRI, CT, and 3D rotational angiography) were automatically fused using a normalized mutual information method, and then reconstructed by a hybrid method combining surface rendering and volume rendering methods. With surface rendering, multimodality and multithreshold techniques for 1 tissue were applied. The completed interactive computer graphics were used for simulation of surgical approaches and assumed surgical fields. Preoperative diagnostic rates for a DVA associated with brainstem cavernous malformation were compared between conventional 2D imaging and interactive computer graphics employing receiver operating characteristic (ROC) analysis. The time required for reconstruction of 3D images was 3-6 hours for interactive computer graphics. Observation in interactive mode required approximately 15 minutes. Detailed anatomical information for operative procedures, from the craniotomy to microsurgical operations, could be visualized and simulated three-dimensionally as 1 computer graphic using interactive computer graphics. Virtual surgical views were consistent with actual operative views. This technique was very useful for examining various surgical approaches. Mean (±SEM) area under the ROC curve for rate of DVA diagnosis was significantly better for interactive computer graphics (1.000±0.000) than for 2D imaging (0.766±0.091; pcomputer graphics than with 2D images. Interactive computer graphics was also useful in helping to plan the surgical

Design and Implementation of High-Performance GIS Dynamic Objects Rendering Engine

Science.gov (United States)

Zhong, Y.; Wang, S.; Li, R.; Yun, W.; Song, G.

2017-12-01

Spatio-temporal dynamic visualization is more vivid than static visualization. It important to use dynamic visualization techniques to reveal the variation process and trend vividly and comprehensively for the geographical phenomenon. To deal with challenges caused by dynamic visualization of both 2D and 3D spatial dynamic targets, especially for different spatial data types require high-performance GIS dynamic objects rendering engine. The main approach for improving the rendering engine with vast dynamic targets relies on key technologies of high-performance GIS, including memory computing, parallel computing, GPU computing and high-performance algorisms. In this study, high-performance GIS dynamic objects rendering engine is designed and implemented for solving the problem based on hybrid accelerative techniques. The high-performance GIS rendering engine contains GPU computing, OpenGL technology, and high-performance algorism with the advantage of 64-bit memory computing. It processes 2D, 3D dynamic target data efficiently and runs smoothly with vast dynamic target data. The prototype system of high-performance GIS dynamic objects rendering engine is developed based SuperMap GIS iObjects. The experiments are designed for large-scale spatial data visualization, the results showed that the high-performance GIS dynamic objects rendering engine have the advantage of high performance. Rendering two-dimensional and three-dimensional dynamic objects achieve 20 times faster on GPU than on CPU.

North American Rendering: processing high quality protein and fats for feed North American Rendering: processamento de proteínas e gorduras de alta qualidade para alimentos para animais

Directory of Open Access Journals (Sweden)

David L. Meeker

2009-07-01

Full Text Available One third to one half of each animal produced for meat, milk, eggs, and fiber is not consumed by humans. These raw materials are subjected to rendering processes resulting in many useful products. Meat and bone meal, meat meal, poultry meal, hydrolyzed feather meal, blood meal, fish meal, and animal fats are the primary products resulting from the rendering process. The most important and valuable use for these animal by-products is as feed ingredients for livestock, poultry, aquaculture, and companion animals. There are volumes of scientific references validating the nutritional qualities of these products, and there are no scientific reasons for altering the practice of feeding rendered products to animals. Government agencies regulate the processing of food and feed, and the rendering industry is scrutinized often. In addition, industry programs include good manufacturing practices, HACCP, Codes of Practice, and third-party certification. The rendering industry clearly understands its role in the safe and nutritious production of animal feed ingredients and has done it very effectively for over 100 years. The availability of rendered products for animal feeds in the future depends on regulation and the market. Regulatory agencies will determine whether certain raw materials can be used for animal feed. The National Renderers Association (NRA supports the use of science as the basis for regulation while aesthetics, product specifications, and quality differences should be left to the market place. Without the rendering industry, the accumulation of unprocessed animal by-products would impede the meat industries and pose a serious potential hazard to animal and human health.De um terço a metade da produção animal para carne, leite, ovos e fibra, não são consumidos pelos seres humanos. Estes materiais não consumidos são sujeitos a processamento em graxarias e indústrias de alimentos de origem animal, resultando em uma série de produtos

GRAPHICS-IMAGE MIXED METHOD FOR LARGE-SCALE BUILDINGS RENDERING

Directory of Open Access Journals (Sweden)

Y. Zhou

2018-05-01

Full Text Available Urban 3D model data is huge and unstructured, LOD and Out-of-core algorithm are usually used to reduce the amount of data that drawn in each frame to improve the rendering efficiency. When the scene is large enough, even the complex optimization algorithm is difficult to achieve better results. Based on the traditional study, a novel idea was developed. We propose a graphics and image mixed method for large-scale buildings rendering. Firstly, the view field is divided into several regions, the graphics-image mixed method used to render the scene on both screen and FBO, then blending the FBO with scree. The algorithm is tested on the huge CityGML model data in the urban areas of New York which contained 188195 public building models, and compared with the Cesium platform. The experiment result shows the system was running smoothly. The experimental results confirm that the algorithm can achieve more massive building scene roaming under the same hardware conditions, and can rendering the scene without vision loss.

Enhancement method for rendered images of home decoration based on SLIC superpixels

Science.gov (United States)

Dai, Yutong; Jiang, Xiaotong

2018-04-01

Rendering technology has been widely used in the home decoration industry in recent years for images of home decoration design. However, due to the fact that rendered images of home decoration design rely heavily on the parameters of renderer and the lights of scenes, most rendered images in this industry require further optimization afterwards. To reduce workload and enhance rendered images automatically, an algorithm utilizing neural networks is proposed in this manuscript. In addition, considering few extreme conditions such as strong sunlight and lights, SLIC superpixels based segmentation is used to choose out these bright areas of an image and enhance them independently. Finally, these chosen areas are merged with the entire image. Experimental results show that the proposed method effectively enhances the rendered images when compared with some existing algorithms. Besides, the proposed strategy is proven to be adaptable especially to those images with obvious bright parts.

Contrast-enhanced computed tomography angiography and volume-rendered imaging for evaluation of cellophane banding in a dog with extrahepatic portosystemic shunt

Directory of Open Access Journals (Sweden)

H. Yoon

2011-04-01

Full Text Available A 4-year-old, 1.8 kg, male, castrated Maltese was presented for evaluation of urolithiasis. Urinary calculi were composed of ammonium biurate. Preprandial and postprandial bile acids were 44.2 and 187.3 μmol/ , respectively (reference ranges 0–10 and 0–20 μmol/ , respectively. Single-phase contrast-enhanced computed tomography angiography (CTA with volume-rendered imaging (VRI was obtained. VRI revealed a portocaval shunt originating just cranial to a tributary of the gastroduodenal vein and draining into the caudal vena cava at the level of the epiploic foramen. CTA revealed a 3.66 mm-diameter shunt measured at the level of the termination of the shunt and a 3.79 mm-diameter portal vein measured at the level between the origin of the shunt and the porta of the liver. Surgery was performed using cellophane banding without attenuation. Follow-up single-phase CTA with VRI was obtained 10 weeks after surgery. VRI revealed no evidence of portosystemic communication on the level of a cellophane band and caudal to the cellophane band. CTA demonstrated an increased portal vein diameter (3.79–5.27 mm measured at the level between the origin of the shunt and the porta of the liver. Preprandial and postprandial bile acids were 25 and 12.5 μmol/ , respectively (aforementioned respective reference ranges, 3 months post-surgery. No problems were evident at 6 months.

Contrast-enhanced MDCT gastrography for detection of early gastric cancer: Initial assessment of “wall-carving image”, a novel volume rendering technique

International Nuclear Information System (INIS)

Komori, Masahiro; Kawanami, Satoshi; Tsurumaru, Daisuke; Matsuura, Shuji; Hiraka, Kiyohisa; Nishie, Akihiro; Honda, Hiroshi

2012-01-01

Objective: We developed a new volume rendering technique, the CT gastrography wall carving image (WC) technique, which provides a clear visualization of localized enhanced tumors in the gastric wall. We evaluated the diagnostic performance of the WC as an adjunct to conventional images in detecting early gastric cancer (EGC). Materials and methods: Thirty-nine patients with 43 EGCs underwent contrast-enhanced MDCT gastrography for preoperative examination. Two observers independently reviewed the images under three different conditions: term 1, Axial CT; term 2, Axial CT, MPR and VE; and term 3, Axial CT, MPR, VE and WC for the detection of EGC. The accuracy of each condition as reviewed by each of the two observers was evaluated by receiver operating characteristic analysis. Interobserver agreement was calculated using weighted-κ statistics. Results: The best diagnostic performance and interobserver agreement were obtained in term 3. The AUCs of the two observers for terms 1, 2, and 3 were 0.63, 0.73, and 0.84, and 0.57, 0.73, and 0.76, respectively. The interobserver agreement improved from fair at term 1 to substantial at term 3. Conclusions: The addition of WC to conventional MDCT display improved the diagnostic accuracy and interobserver reproducibility for the detection of ECG. WC represents a suitable alternative for the visualization of localized enhanced tumors in the gastric wall.

Ambient temperature and volume of perihematomal edema in acute intracerebral haemorrhage: the INTERACT1 study.

Science.gov (United States)

Zheng, Danni; Arima, Hisatomi; Heeley, Emma; Karpin, Anne; Yang, Jie; Chalmers, John; Anderson, Craig S

2015-01-01

As no human data exist, we aimed to determine the relation between ambient temperature and volume of perihematomal 'cerebral' edema in acute spontaneous intracerebral haemorrhage (ICH) among Chinese participants of the pilot phase, Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial (INTERACT1). INTERACT1 was a multicenter, open, blind outcome assessed, randomized controlled trial of intensive (systolic target ambient temperature (mean, minimum, maximum, and range) on the day of each participant's ICH obtained from China Meteorological Data Sharing Service System were linked to other data including edema volumes. Multivariable regression analyses were performed to evaluate association between ambient temperature and edema volumes. A generalized linear regression model with a generalized estimating equations approach (GEE) was used to assess any association of ambient temperature and change in edema volume over 72 h. A total of 250 of all 384 Chinese participants had complete data that showed positive associations between ambient temperature (mean and minimum temperatures) and edema volumes at each time point over 72 h after hospital admission (all P ambient temperature and perihematomal edema volume in acute spontaneous ICH. © 2014 World Stroke Organization.

Integral image rendering procedure for aberration correction and size measurement.

Science.gov (United States)

Sommer, Holger; Ihrig, Andreas; Ebenau, Melanie; Flühs, Dirk; Spaan, Bernhard; Eichmann, Marion

2014-05-20

The challenge in rendering integral images is to use as much information preserved by the light field as possible to reconstruct a captured scene in a three-dimensional way. We propose a rendering algorithm based on the projection of rays through a detailed simulation of the optical path, considering all the physical properties and locations of the optical elements. The rendered images contain information about the correct size of imaged objects without the need to calibrate the imaging device. Additionally, aberrations of the optical system may be corrected, depending on the setup of the integral imaging device. We show simulation data that illustrates the aberration correction ability and experimental data from our plenoptic camera, which illustrates the capability of our proposed algorithm to measure size and distance. We believe this rendering procedure will be useful in the future for three-dimensional ophthalmic imaging of the human retina.

Employing WebGL to develop interactive stereoscopic 3D content for use in biomedical visualization

Science.gov (United States)

Johnston, Semay; Renambot, Luc; Sauter, Daniel

2013-03-01

Web Graphics Library (WebGL), the forthcoming web standard for rendering native 3D graphics in a browser, represents an important addition to the biomedical visualization toolset. It is projected to become a mainstream method of delivering 3D online content due to shrinking support for third-party plug-ins. Additionally, it provides a virtual reality (VR) experience to web users accommodated by the growing availability of stereoscopic displays (3D TV, desktop, and mobile). WebGL's value in biomedical visualization has been demonstrated by applications for interactive anatomical models, chemical and molecular visualization, and web-based volume rendering. However, a lack of instructional literature specific to the field prevents many from utilizing this technology. This project defines a WebGL design methodology for a target audience of biomedical artists with a basic understanding of web languages and 3D graphics. The methodology was informed by the development of an interactive web application depicting the anatomy and various pathologies of the human eye. The application supports several modes of stereoscopic displays for a better understanding of 3D anatomical structures.

Light Field Rendering for Head Mounted Displays using Pixel Reprojection

DEFF Research Database (Denmark)

Hansen, Anne Juhler; Klein, Jákup; Kraus, Martin

2017-01-01

Light field displays have advantages over traditional stereoscopic head mounted displays, for example, because they can overcome the vergence-accommodation conflict. However, rendering light fields can be a heavy task for computers due to the number of images that have to be rendered. Since much ...

Light Field Rendering for Head Mounted Displays using Pixel Reprojection

DEFF Research Database (Denmark)

Hansen, Anne Juhler; Klein, Jákup; Kraus, Martin

2017-01-01

of the information of the different images is redundant, we use pixel reprojection from the corner cameras to compute the remaining images in the light field. We compare the reprojected images with directly rendered images in a user test. In most cases, the users were unable to distinguish the images. In extreme...... cases, the reprojection approach is not capable of creating the light field. We conclude that pixel reprojection is a feasible method for rendering light fields as far as quality of perspective and diffuse shading is concerned, but render time needs to be reduced to make the method practical....

Interactive indirect illumination using adaptive multiresolution splatting.

Science.gov (United States)

Nichols, Greg; Wyman, Chris

2010-01-01

Global illumination provides a visual richness not achievable with the direct illumination models used by most interactive applications. To generate global effects, numerous approximations attempt to reduce global illumination costs to levels feasible in interactive contexts. One such approximation, reflective shadow maps, samples a shadow map to identify secondary light sources whose contributions are splatted into eye space. This splatting introduces significant overdraw that is usually reduced by artificially shrinking each splat's radius of influence. This paper introduces a new multiresolution approach for interactively splatting indirect illumination. Instead of reducing GPU fill rate by reducing splat size, we reduce fill rate by rendering splats into a multiresolution buffer. This takes advantage of the low-frequency nature of diffuse and glossy indirect lighting, allowing rendering of indirect contributions at low resolution where lighting changes slowly and at high-resolution near discontinuities. Because this multiresolution rendering occurs on a per-splat basis, we can significantly reduce fill rate without arbitrarily clipping splat contributions below a given threshold-those regions simply are rendered at a coarse resolution.

Architecture for high performance stereoscopic game rendering on Android

Science.gov (United States)

Flack, Julien; Sanderson, Hugh; Shetty, Sampath

2014-03-01

Stereoscopic gaming is a popular source of content for consumer 3D display systems. There has been a significant shift in the gaming industry towards casual games for mobile devices running on the Android™ Operating System and driven by ARM™ and other low power processors. Such systems are now being integrated directly into the next generation of 3D TVs potentially removing the requirement for an external games console. Although native stereo support has been integrated into some high profile titles on established platforms like Windows PC and PS3 there is a lack of GPU independent 3D support for the emerging Android platform. We describe a framework for enabling stereoscopic 3D gaming on Android for applications on mobile devices, set top boxes and TVs. A core component of the architecture is a 3D game driver, which is integrated into the Android OpenGL™ ES graphics stack to convert existing 2D graphics applications into stereoscopic 3D in real-time. The architecture includes a method of analyzing 2D games and using rule based Artificial Intelligence (AI) to position separate objects in 3D space. We describe an innovative stereo 3D rendering technique to separate the views in the depth domain and render directly into the display buffer. The advantages of the stereo renderer are demonstrated by characterizing the performance in comparison to more traditional render techniques, including depth based image rendering, both in terms of frame rates and impact on battery consumption.

Extreme Simplification and Rendering of Point Sets using Algebraic Multigrid

NARCIS (Netherlands)

Reniers, Dennie; Telea, Alexandru

2005-01-01

We present a novel approach for extreme simplification of point set models in the context of real-time rendering. Point sets are often rendered using simple point primitives, such as oriented discs. However efficient, simple primitives are less effective in approximating large surface areas. A large

A Case Study of a Hybrid Parallel 3D Surface Rendering Graphics Architecture

DEFF Research Database (Denmark)

Holten-Lund, Hans Erik; Madsen, Jan; Pedersen, Steen

1997-01-01

This paper presents a case study in the design strategy used inbuilding a graphics computer, for drawing very complex 3Dgeometric surfaces. The goal is to build a PC based computer systemcapable of handling surfaces built from about 2 million triangles, andto be able to render a perspective view...... of these on a computer displayat interactive frame rates, i.e. processing around 50 milliontriangles per second. The paper presents a hardware/softwarearchitecture called HPGA (Hybrid Parallel Graphics Architecture) whichis likely to be able to carry out this task. The case study focuses ontechniques to increase...

Volume-rendered hemorrhage-responsible arteriogram created by 64 multidetector-row CT during aortography: utility for catheterization in transcatheter arterial embolization for acute arterial bleeding.

Science.gov (United States)

Minamiguchi, Hiroki; Kawai, Nobuyuki; Sato, Morio; Ikoma, Akira; Sanda, Hiroki; Nakata, Kouhei; Tanaka, Fumihiro; Nakai, Motoki; Sonomura, Tetsuo; Murotani, Kazuhiro; Hosokawa, Seiki; Nishioku, Tadayoshi

2014-01-01

Aortography for detecting hemorrhage is limited when determining the catheter treatment strategy because the artery responsible for hemorrhage commonly overlaps organs and non-responsible arteries. Selective catheterization of untargeted arteries would result in repeated arteriography, large volumes of contrast medium, and extended time. A volume-rendered hemorrhage-responsible arteriogram created with 64 multidetector-row CT (64MDCT) during aortography (MDCTAo) can be used both for hemorrhage mapping and catheter navigation. The MDCTAo depicted hemorrhage in 61 of 71 cases of suspected acute arterial bleeding treated at our institute in the last 3 years. Complete hemostasis by embolization was achieved in all cases. The hemorrhage-responsible arteriogram was used for navigation during catheterization, thus assisting successful embolization. Hemorrhage was not visualized in the remaining 10 patients, of whom 6 had a pseudoaneurysm in a visceral artery; 1 with urinary bladder bleeding and 1 with chest wall hemorrhage had gaze tamponade; and 1 with urinary bladder hemorrhage and 1 with uterine hemorrhage had spastic arteries. Six patients with pseudoaneurysm underwent preventive embolization and the other 4 patients were managed by watchful observation. MDCTAo has the advantage of depicting the arteries responsible for hemoptysis, whether from the bronchial arteries or other systemic arteries, in a single scan. MDCTAo is particularly useful for identifying the source of acute arterial bleeding in the pancreatic arcade area, which is supplied by both the celiac and superior mesenteric arteries. In a case of pelvic hemorrhage, MDCTAo identified the responsible artery from among numerous overlapping visceral arteries that branched from the internal iliac arteries. In conclusion, a hemorrhage-responsible arteriogram created by 64MDCT immediately before catheterization is useful for deciding the catheter treatment strategy for acute arterial bleeding.

Artist rendering of dust grains colliding at low speeds

Science.gov (United States)

2003-01-01

Clues to the formation of planets and planetary rings -- like Saturn's dazzling ring system -- may be found by studying how dust grains interact as they collide at low speeds. To study the question of low-speed dust collisions, NASA sponsored the COLLisions Into Dust Experiment (COLLIDE) at the University of Colorado. It was designed to spring-launch marble-size projectiles into trays of powder similar to space or lunar dust. COLLIDE-1 (1998) discovered that collisions below a certain energy threshold eject no material. COLLIDE-2 was designed to identify where the threshold is. In COLLIDE-2, scientists nudged small projectiles into dust beds and recorded how the dust splashed outward (video frame at top; artist's rendering at bottom). The slowest impactor ejected no material and stuck in the target. The faster impactors produced ejecta; some rebounded while others stuck in the target.

An improved method of continuous LOD based on fractal theory in terrain rendering

Science.gov (United States)

Lin, Lan; Li, Lijun

2007-11-01

With the improvement of computer graphic hardware capability, the algorithm of 3D terrain rendering is going into the hot topic of real-time visualization. In order to solve conflict between the rendering speed and reality of rendering, this paper gives an improved method of terrain rendering which improves the traditional continuous level of detail technique based on fractal theory. This method proposes that the program needn't to operate the memory repeatedly to obtain different resolution terrain model, instead, obtains the fractal characteristic parameters of different region according to the movement of the viewpoint. Experimental results show that the method guarantees the authenticity of landscape, and increases the real-time 3D terrain rendering speed.

Fast rendering of scanned room geometries

DEFF Research Database (Denmark)

Olesen, Søren Krarup; Markovic, Milos; Hammershøi, Dorte

2014-01-01

Room acoustics are rendered in Virtual Realities based on models of the real world. These are typically rather coarse representations of the true geometry resulting in room impulse responses with a lack of natural detail. This problem can be overcome by using data scanned by sensors, such as e...

On-the-fly generation and rendering of infinite cities on the GPU

KAUST Repository

Steinberger, Markus

2014-05-01

In this paper, we present a new approach for shape-grammar-based generation and rendering of huge cities in real-time on the graphics processing unit (GPU). Traditional approaches rely on evaluating a shape grammar and storing the geometry produced as a preprocessing step. During rendering, the pregenerated data is then streamed to the GPU. By interweaving generation and rendering, we overcome the problems and limitations of streaming pregenerated data. Using our methods of visibility pruning and adaptive level of detail, we are able to dynamically generate only the geometry needed to render the current view in real-time directly on the GPU. We also present a robust and efficient way to dynamically update a scene\\'s derivation tree and geometry, enabling us to exploit frame-to-frame coherence. Our combined generation and rendering is significantly faster than all previous work. For detailed scenes, we are capable of generating geometry more rapidly than even just copying pregenerated data from main memory, enabling us to render cities with thousands of buildings at up to 100 frames per second, even with the camera moving at supersonic speed. © 2014 The Author(s) Computer Graphics Forum © 2014 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

On-the-fly generation and rendering of infinite cities on the GPU

KAUST Repository

Steinberger, Markus; Kenzel, Michael; Kainz, Bernhard K.; Wonka, Peter; Schmalstieg, Dieter

2014-01-01

In this paper, we present a new approach for shape-grammar-based generation and rendering of huge cities in real-time on the graphics processing unit (GPU). Traditional approaches rely on evaluating a shape grammar and storing the geometry produced as a preprocessing step. During rendering, the pregenerated data is then streamed to the GPU. By interweaving generation and rendering, we overcome the problems and limitations of streaming pregenerated data. Using our methods of visibility pruning and adaptive level of detail, we are able to dynamically generate only the geometry needed to render the current view in real-time directly on the GPU. We also present a robust and efficient way to dynamically update a scene's derivation tree and geometry, enabling us to exploit frame-to-frame coherence. Our combined generation and rendering is significantly faster than all previous work. For detailed scenes, we are capable of generating geometry more rapidly than even just copying pregenerated data from main memory, enabling us to render cities with thousands of buildings at up to 100 frames per second, even with the camera moving at supersonic speed. © 2014 The Author(s) Computer Graphics Forum © 2014 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

Facilitating the design of multidimensional and local transfer functions for volume visualization

NARCIS (Netherlands)

Sereda, P.

2007-01-01

The importance of volume visualization is increasing since the sizes of the datasets that need to be inspected grow with every new version of medical scanners (e.g., CT and MR). Direct volume rendering is a 3D visualization technique that has, in many cases, clear benefits over 2D views. It is able

Democratizing rendering for multiple viewers in surround VR systems

KAUST Repository

Schulze, Jü rgen P.; Acevedo-Feliz, Daniel; Mangan, John; Prudhomme, Andrew; Nguyen, Phi Khanh; Weber, Philip P.

2012-01-01

We present a new approach for how multiple users' views can be rendered in a surround virtual environment without using special multi-view hardware. It is based on the idea that different parts of the screen are often viewed by different users, so that they can be rendered from their own view point, or at least from a point closer to their view point than traditionally expected. The vast majority of 3D virtual reality systems are designed for one head-tracked user, and a number of passive viewers. Only the head tracked user gets to see the correct view of the scene, everybody else sees a distorted image. We reduce this problem by algorithmically democratizing the rendering view point among all tracked users. Researchers have proposed solutions for multiple tracked users, but most of them require major changes to the display hardware of the VR system, such as additional projectors or custom VR glasses. Our approach does not require additional hardware, except the ability to track each participating user. We propose three versions of our multi-viewer algorithm. Each of them balances image distortion and frame rate in different ways, making them more or less suitable for certain application scenarios. Our most sophisticated algorithm renders each pixel from its own, optimized camera perspective, which depends on all tracked users' head positions and orientations. © 2012 IEEE.

Democratizing rendering for multiple viewers in surround VR systems

KAUST Repository

Schulze, Jürgen P.

2012-03-01

We present a new approach for how multiple users\\' views can be rendered in a surround virtual environment without using special multi-view hardware. It is based on the idea that different parts of the screen are often viewed by different users, so that they can be rendered from their own view point, or at least from a point closer to their view point than traditionally expected. The vast majority of 3D virtual reality systems are designed for one head-tracked user, and a number of passive viewers. Only the head tracked user gets to see the correct view of the scene, everybody else sees a distorted image. We reduce this problem by algorithmically democratizing the rendering view point among all tracked users. Researchers have proposed solutions for multiple tracked users, but most of them require major changes to the display hardware of the VR system, such as additional projectors or custom VR glasses. Our approach does not require additional hardware, except the ability to track each participating user. We propose three versions of our multi-viewer algorithm. Each of them balances image distortion and frame rate in different ways, making them more or less suitable for certain application scenarios. Our most sophisticated algorithm renders each pixel from its own, optimized camera perspective, which depends on all tracked users\\' head positions and orientations. © 2012 IEEE.

Volumetric visualization of head and neck CT data for treatment planning

International Nuclear Information System (INIS)

Lee, Jean S.; Jani, Ashesh B.; Pelizzari, Charles A.; Haraf, Daniel J.; Vokes, Everett E.; Weichselbaum, Ralph R.; Chen, George T.Y.

1999-01-01

Purpose: To demonstrate the utility of volume rendering, an alternative visualization technique to surface rendering, in the practice of CT based radiotherapy planning for the head and neck. Methods and Materials: Rendo-avs, a volume visualization tool developed at the University of Chicago, was used to volume render head and neck CT scans from two cases. Rendo-avs is a volume rendering tool operating within the graphical user interface environment of AVS (Application Visualization System). Users adjust the opacity of various tissues by defining the opacity transfer function (OTF), a function which preclassifies voxels by opacity prior to rendering. By defining the opacity map (OTF), the user selectively enhances and suppresses structures of various intensity. Additional graphics tools are available within the AVS network, allowing for the manipulation of perspective, field of view, data orientation. Users may draw directly on volume rendered images, create a partial surface, and thereby correlate objects in the 3D scene to points on original axial slices. Information in volume rendered images is mapped into the original CT slices via a Z buffer, which contains the depth information (Z coordinate) for each pixel in the rendered view. Locally developed software was used to project conventionally designed GTV contours onto volume rendered images. Results: The lymph nodes, salivary glands, vessels, and airway are visualized in detail without prior manual segmentation. Volume rendering can be used to explore the finer anatomic structures that appear on consecutive axial slices as 'points'. Rendo-avs allowed for acceptable interactivity, with a processing time of approximately 5 seconds per 256 x 256 pixel output image. Conclusions: Volume rendering is a useful alternative to surface rendering, offering high-quality visualization, 3D anatomic delineation, and time savings to the user, due to the elimination of manual segmentation as a preprocessing step. Volume rendered

Interactive initialization of 2D/3D rigid registration

Energy Technology Data Exchange (ETDEWEB)

Gong, Ren Hui; Güler, Özgür [The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children' s National Medical Center, Washington, DC 20010 (United States); Kürklüoglu, Mustafa [Department of Cardiac Surgery, Children' s National Medical Center, Washington, DC 20010 (United States); Lovejoy, John [Department of Orthopaedic Surgery and Sports Medicine, Children' s National Medical Center, Washington, DC 20010 (United States); Yaniv, Ziv, E-mail: ZYaniv@childrensnational.org [The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children' s National Medical Center, Washington, DC 20010 and Departments of Pediatrics and Radiology, George Washington University, Washington, DC 20037 (United States)

2013-12-15

Purpose: Registration is one of the key technical components in an image-guided navigation system. A large number of 2D/3D registration algorithms have been previously proposed, but have not been able to transition into clinical practice. The authors identify the primary reason for the lack of adoption with the prerequisite for a sufficiently accurate initial transformation, mean target registration error of about 10 mm or less. In this paper, the authors present two interactive initialization approaches that provide the desired accuracy for x-ray/MR and x-ray/CT registration in the operating room setting. Methods: The authors have developed two interactive registration methods based on visual alignment of a preoperative image, MR, or CT to intraoperative x-rays. In the first approach, the operator uses a gesture based interface to align a volume rendering of the preoperative image to multiple x-rays. The second approach uses a tracked tool available as part of a navigation system. Preoperatively, a virtual replica of the tool is positioned next to the anatomical structures visible in the volumetric data. Intraoperatively, the physical tool is positioned in a similar manner and subsequently used to align a volume rendering to the x-ray images using an augmented reality (AR) approach. Both methods were assessed using three publicly available reference data sets for 2D/3D registration evaluation. Results: In the authors' experiments, the authors show that for x-ray/MR registration, the gesture based method resulted in a mean target registration error (mTRE) of 9.3 ± 5.0 mm with an average interaction time of 146.3 ± 73.0 s, and the AR-based method had mTREs of 7.2 ± 3.2 mm with interaction times of 44 ± 32 s. For x-ray/CT registration, the gesture based method resulted in a mTRE of 7.4 ± 5.0 mm with an average interaction time of 132.1 ± 66.4 s, and the AR-based method had mTREs of 8.3 ± 5.0 mm with interaction times of 58 ± 52 s. Conclusions: Based on

Interactive initialization of 2D/3D rigid registration

International Nuclear Information System (INIS)

Gong, Ren Hui; Güler, Özgür; Kürklüoglu, Mustafa; Lovejoy, John; Yaniv, Ziv

2013-01-01

Purpose: Registration is one of the key technical components in an image-guided navigation system. A large number of 2D/3D registration algorithms have been previously proposed, but have not been able to transition into clinical practice. The authors identify the primary reason for the lack of adoption with the prerequisite for a sufficiently accurate initial transformation, mean target registration error of about 10 mm or less. In this paper, the authors present two interactive initialization approaches that provide the desired accuracy for x-ray/MR and x-ray/CT registration in the operating room setting. Methods: The authors have developed two interactive registration methods based on visual alignment of a preoperative image, MR, or CT to intraoperative x-rays. In the first approach, the operator uses a gesture based interface to align a volume rendering of the preoperative image to multiple x-rays. The second approach uses a tracked tool available as part of a navigation system. Preoperatively, a virtual replica of the tool is positioned next to the anatomical structures visible in the volumetric data. Intraoperatively, the physical tool is positioned in a similar manner and subsequently used to align a volume rendering to the x-ray images using an augmented reality (AR) approach. Both methods were assessed using three publicly available reference data sets for 2D/3D registration evaluation. Results: In the authors' experiments, the authors show that for x-ray/MR registration, the gesture based method resulted in a mean target registration error (mTRE) of 9.3 ± 5.0 mm with an average interaction time of 146.3 ± 73.0 s, and the AR-based method had mTREs of 7.2 ± 3.2 mm with interaction times of 44 ± 32 s. For x-ray/CT registration, the gesture based method resulted in a mTRE of 7.4 ± 5.0 mm with an average interaction time of 132.1 ± 66.4 s, and the AR-based method had mTREs of 8.3 ± 5.0 mm with interaction times of 58 ± 52 s. Conclusions: Based on the

Method of producing hydrogen, and rendering a contaminated biomass inert

Science.gov (United States)

Bingham, Dennis N [Idaho Falls, ID; Klingler, Kerry M [Idaho Falls, ID; Wilding, Bruce M [Idaho Falls, ID

2010-02-23

A method for rendering a contaminated biomass inert includes providing a first composition, providing a second composition, reacting the first and second compositions together to form an alkaline hydroxide, providing a contaminated biomass feedstock and reacting the alkaline hydroxide with the contaminated biomass feedstock to render the contaminated biomass feedstock inert and further producing hydrogen gas, and a byproduct that includes the first composition.

How a change in the interaction potential affects the p-wave scattering volume

International Nuclear Information System (INIS)

Jamieson, M J; Dalgarno, A

2012-01-01

We derive a simple expression for the change in the s-wave scattering length in terms of zero-energy wavefunctions, we generalize it to obtain an expression for the change in the p-wave scattering volume and we use both expressions to derive the first order differential equations of variable phase theory that are satisfied by the closely related accumulated scattering length and volume. We provide numerical demonstrations for the example of a pair of hydrogen atoms interacting via the X 1 Σ + g molecular state. (fast track communication)

Rendering Visible: Painting and Sexuate Subjectivity

Science.gov (United States)

Daley, Linda

2015-01-01

In this essay, I examine Luce Irigaray's aesthetic of sexual difference, which she develops by extrapolating from Paul Klee's idea that the role of painting is to render the non-visible rather than represent the visible. This idea is the premise of her analyses of phenomenology and psychoanalysis and their respective contributions to understanding…

Influence of rendering methods on yield and quality of chicken fat recovered from broiler skin

Directory of Open Access Journals (Sweden)

Liang-Kun Lin

2017-06-01

Full Text Available Objective In order to utilize fat from broiler byproducts efficiently, it is necessary to develop an appropriate rendering procedure and establish quality information for the rendered fat. A study was therefore undertaken to evaluate the influence of rendering methods on the amounts and general properties of the fat recovered from broiler skin. Methods The yield and quality of the broiler skin fat rendered through high and lower energy microwave rendering (3.6 W/g for 10 min and 2.4 W/g for 10 min for high power microwave rendering (HPMR and high power microwave rendering (LPMR, respectively, oven baking (OB, at 180°C for 40 min, and water cooking (WC, boiling for 40 min were compared. Results Microwave-rendered skin exhibited the highest yields and fat recovery rates, followed by OB, and WC fats (p<0.05. HPMR fat had the highest L*, a*, and b* values, whereas WC fat had the highest moisture content, acid values, and thiobarbituric acid (TBA values (p<0.05. There was no significant difference in the acid value, peroxide value, and TBA values between HPMR and LPMR fats. Conclusion Microwave rendering at a power level of 3.6 W/g for 10 min is suggested base on the yield and quality of chicken fat.

Hydrogen bonding interactions between ethylene glycol and water: density, excess molar volume, and spectral study

Institute of Scientific and Technical Information of China (English)

ZHANG JianBin; ZHANG PengYan; MA Kai; HAN Fang; CHEN GuoHua; WEI XiongHui

2008-01-01

Studies of the density and the excess molar volume of ethylene glycol (EG)-water mixtures were carried out to illustrate the hydrogen bonding interactions of EG with water at different temperatures, The re-sults suggest that a likely complex of 3 ethylene glycol molecules bonding with 4 water molecules in an ethylene glycol-water mixture (EGW) is formed at the maximal excess molar volume, which displays stronger absorption capabilities for SO2 when the concentration of SO2 reaches 400×106 (volume ratio) in the gas phase. Meanwhile, FTIR and UV spectra of EGWs were recorded at various EG concentra-tions to display the hydrogen bonding interactions of EG with water. The FTIR spectra show that the stretching vibrational band of hydroxyl in the EGWs shifts to a lower frequency and the bending vibra-tional band of water shifts to a higher frequency with increasing the EG concentration, respectively. Furthermore, the UV spectra show that the electron transferring band of the hydroxyl oxygen in EG shows red shift with increasing the EG concentration. The frequency shifts in FTIR spectra and the shifts of absorption bands in UV absorption spectra of EGWs are interpreted as the strong hydrogen bonding interactions of the hydrogen atoms in water with the hydroxyl oxygen atoms of EG.

Hydrogen bonding interactions between ethylene glycol and water:density,excess molar volume,and spectral study

Institute of Scientific and Technical Information of China (English)

2008-01-01

Studies of the density and the excess molar volume of ethylene glycol (EG)-water mixtures were carried out to illustrate the hydrogen bonding interactions of EG with water at different temperatures. The re-sults suggest that a likely complex of 3 ethylene glycol molecules bonding with 4 water molecules in an ethylene glycol-water mixture (EGW) is formed at the maximal excess molar volume,which displays stronger absorption capabilities for SO2 when the concentration of SO2 reaches 400×10?6 (volume ratio) in the gas phase. Meanwhile,FTIR and UV spectra of EGWs were recorded at various EG concentra-tions to display the hydrogen bonding interactions of EG with water. The FTIR spectra show that the stretching vibrational band of hydroxyl in the EGWs shifts to a lower frequency and the bending vibra-tional band of water shifts to a higher frequency with increasing the EG concentration,respectively. Furthermore,the UV spectra show that the electron transferring band of the hydroxyl oxygen in EG shows red shift with increasing the EG concentration. The frequency shifts in FTIR spectra and the shifts of absorption bands in UV absorption spectra of EGWs are interpreted as the strong hydrogen bonding interactions of the hydrogen atoms in water with the hydroxyl oxygen atoms of EG.

Automated volume of interest delineation and rendering of cone beam CT images in interventional cardiology

Science.gov (United States)

Lorenz, Cristian; Schäfer, Dirk; Eshuis, Peter; Carroll, John; Grass, Michael

2012-02-01

Interventional C-arm systems allow the efficient acquisition of 3D cone beam CT images. They can be used for intervention planning, navigation, and outcome assessment. We present a fast and completely automated volume of interest (VOI) delineation for cardiac interventions, covering the whole visceral cavity including mediastinum and lungs but leaving out rib-cage and spine. The problem is addressed in a model based approach. The procedure has been evaluated on 22 patient cases and achieves an average surface error below 2mm. The method is able to cope with varying image intensities, varying truncations due to the limited reconstruction volume, and partially with heavy metal and motion artifacts.

Evaluation and Improvement of the CIE Metameric and Colour Rendering Index

Directory of Open Access Journals (Sweden)

Radovan Slavuj

2015-12-01

Full Text Available All artificial light sources are intended to simulate daylight and its properties of color rendering or ability of colour discrimination. Two indices, defined by the CIE, are used to quantify quality of the artificial light sources. First is Color Rendering Index which quantifies ability of light sources to render colours and other is the Metemerism Index which describes metamerism potential of given light source. Calculation of both indices are defined by CIE and has been a subject of discussion and change in past. In this work particularly, the problem of sample number and type used in calculation is addressed here and evaluated. It is noticed that both indices depends on the choice and sample number and that they should be determined based on application.

Experiencing "Macbeth": From Text Rendering to Multicultural Performance.

Science.gov (United States)

Reisin, Gail

1993-01-01

Shows how one teacher used innovative methods in teaching William Shakespeare's "Macbeth." Outlines student assignments including text renderings, rewriting a scene from the play, and creating a multicultural scrapbook for the play. (HB)

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp

International Nuclear Information System (INIS)

Bayr, S.; Ojanperä, M.; Kaparaju, P.; Rintala, J.

2014-01-01

Highlights: • Rendering wastes’ mono-digestion and co-digestion with potato pulp were studied. • CSTR process with OLR of 1.5 kg VS/m 3 d, HRT of 50 d was unstable in mono-digestion. • Free NH 3 inhibited mono-digestion of rendering wastes. • CSTR process with OLR of 1.5 kg VS/m 3 d, HRT of 50 d was stable in co-digestion. • Co-digestion increased methane yield somewhat compared to mono-digestion. - Abstract: In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55 °C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH 4 -N and/or free NH 3 ) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m 3 d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm 3 /kg VS fed . On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500–680 dm 3 /kg VS fed ). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials

Screen Space Ambient Occlusion Based Multiple Importance Sampling for Real-Time Rendering

Science.gov (United States)

Zerari, Abd El Mouméne; Babahenini, Mohamed Chaouki

2018-03-01

We propose a new approximation technique for accelerating the Global Illumination algorithm for real-time rendering. The proposed approach is based on the Screen-Space Ambient Occlusion (SSAO) method, which approximates the global illumination for large, fully dynamic scenes at interactive frame rates. Current algorithms that are based on the SSAO method suffer from difficulties due to the large number of samples that are required. In this paper, we propose an improvement to the SSAO technique by integrating it with a Multiple Importance Sampling technique that combines a stratified sampling method with an importance sampling method, with the objective of reducing the number of samples. Experimental evaluation demonstrates that our technique can produce high-quality images in real time and is significantly faster than traditional techniques.

ACCELERATION RENDERING METHOD ON RAY TRACING WITH ANGLE COMPARISON AND DISTANCE COMPARISON

Directory of Open Access Journals (Sweden)

Liliana liliana

2007-01-01

Full Text Available In computer graphics applications, to produce realistic images, a method that is often used is ray tracing. Ray tracing does not only model local illumination but also global illumination. Local illumination count ambient, diffuse and specular effects only, but global illumination also count mirroring and transparency. Local illumination count effects from the lamp(s but global illumination count effects from other object(s too. Objects that are usually modeled are primitive objects and mesh objects. The advantage of mesh modeling is various, interesting and real-like shape. Mesh contains many primitive objects like triangle or square (rare. A problem in mesh object modeling is long rendering time. It is because every ray must be checked with a lot of triangle of the mesh. Added by ray from other objects checking, the number of ray that traced will increase. It causes the increasing of rendering time. To solve this problem, in this research, new methods are developed to make the rendering process of mesh object faster. The new methods are angle comparison and distance comparison. These methods are used to reduce the number of ray checking. The rays predicted will not intersect with the mesh, are not checked weather the ray intersects the mesh. With angle comparison, if using small angle to compare, the rendering process will be fast. This method has disadvantage, if the shape of each triangle is big, some triangles will be corrupted. If the angle to compare is bigger, mesh corruption can be avoided but the rendering time will be longer than without comparison. With distance comparison, the rendering time is less than without comparison, and no triangle will be corrupted.

Analysis of electromagnetic wave interactions on nonlinear scatterers using time domain volume integral equations

KAUST Repository

Ulku, Huseyin Arda

2014-07-06

Effects of material nonlinearities on electromagnetic field interactions become dominant as field amplitudes increase. A typical example is observed in plasmonics, where highly localized fields “activate” Kerr nonlinearities. Naturally, time domain solvers are the method of choice when it comes simulating these nonlinear effects. Oftentimes, finite difference time domain (FDTD) method is used for this purpose. This is simply due to the fact that explicitness of the FDTD renders the implementation easier and the material nonlinearity can be easily accounted for using an auxiliary differential equation (J.H. Green and A. Taflove, Opt. Express, 14(18), 8305-8310, 2006). On the other hand, explicit marching on-in-time (MOT)-based time domain integral equation (TDIE) solvers have never been used for the same purpose even though they offer several advantages over FDTD (E. Michielssen, et al., ECCOMAS CFD, The Netherlands, Sep. 5-8, 2006). This is because explicit MOT solvers have never been stabilized until not so long ago. Recently an explicit but stable MOT scheme has been proposed for solving the time domain surface magnetic field integral equation (H.A. Ulku, et al., IEEE Trans. Antennas Propag., 61(8), 4120-4131, 2013) and later it has been extended for the time domain volume electric field integral equation (TDVEFIE) (S. B. Sayed, et al., Pr. Electromagn. Res. S., 378, Stockholm, 2013). This explicit MOT scheme uses predictor-corrector updates together with successive over relaxation during time marching to stabilize the solution even when time step is as large as in the implicit counterpart. In this work, an explicit MOT-TDVEFIE solver is proposed for analyzing electromagnetic wave interactions on scatterers exhibiting Kerr nonlinearity. Nonlinearity is accounted for using the constitutive relation between the electric field intensity and flux density. Then, this relation and the TDVEFIE are discretized together by expanding the intensity and flux - sing half

Bare-Hand Volume Cracker for Raw Volume Data Analysis

Directory of Open Access Journals (Sweden)

Bireswar Laha

2016-09-01

Full Text Available Analysis of raw volume data generated from different scanning technologies faces a variety of challenges, related to search, pattern recognition, spatial understanding, quantitative estimation, and shape description. In a previous study, we found that the Volume Cracker (VC 3D interaction (3DI technique mitigated some of these problems, but this result was from a tethered glove-based system with users analyzing simulated data. Here, we redesigned the VC by using untethered bare-hand interaction with real volume datasets, with a broader aim of adoption of this technique in research labs. We developed symmetric and asymmetric interfaces for the Bare-Hand Volume Cracker (BHVC through design iterations with a biomechanics scientist. We evaluated our asymmetric BHVC technique against standard 2D and widely used 3D interaction techniques with experts analyzing scanned beetle datasets. We found that our BHVC design significantly outperformed the other two techniques. This study contributes a practical 3DI design for scientists, documents lessons learned while redesigning for bare-hand trackers, and provides evidence suggesting that 3D interaction could improve volume data analysis for a variety of visual analysis tasks. Our contribution is in the realm of 3D user interfaces tightly integrated with visualization, for improving the effectiveness of visual analysis of volume datasets. Based on our experience, we also provide some insights into hardware-agnostic principles for design of effective interaction techniques.

31 CFR 515.548 - Services rendered by Cuba to United States aircraft.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Services rendered by Cuba to United... REGULATIONS Licenses, Authorizations, and Statements of Licensing Policy § 515.548 Services rendered by Cuba to United States aircraft. Specific licenses are issued for payment to Cuba of charges for services...

Combined surface and volumetric occlusion shading

KAUST Repository

Schott, Matthias O.; Martin, Tobias; Grosset, A. V Pascal; Brownlee, Carson; Hollt, Thomas; Brown, Benjamin P.; Smith, Sean T.; Hansen, Charles D.

2012-01-01

In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

Combined surface and volumetric occlusion shading

KAUST Repository

Schott, Matthias O.

2012-02-01

In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

COMPANION ANIMALS SYMPOSIUM: Rendered ingredients significantly influence sustainability, quality, and safety of pet food.

Science.gov (United States)

Meeker, D L; Meisinger, J L

2015-03-01

The rendering industry collects and safely processes approximately 25 million t of animal byproducts each year in the United States. Rendering plants process a variety of raw materials from food animal production, principally offal from slaughterhouses, but include whole animals that die on farms or in transit and other materials such as bone, feathers, and blood. By recycling these byproducts into various protein, fat, and mineral products, including meat and bone meal, hydrolyzed feather meal, blood meal, and various types of animal fats and greases, the sustainability of food animal production is greatly enhanced. The rendering industry is conscious of its role in the prevention of disease and microbiological control and providing safe feed ingredients for livestock, poultry, aquaculture, and pets. The processing of otherwise low-value OM from the livestock production and meat processing industries through rendering drastically reduces the amount of waste. If not rendered, biological materials would be deposited in landfills, burned, buried, or inappropriately dumped with large amounts of carbon dioxide, ammonia, and other compounds polluting air and water. The majority of rendered protein products are used as animal feed. Rendered products are especially valuable to the livestock and pet food industries because of their high protein content, digestible AA levels (especially lysine), mineral availability (especially calcium and phosphorous), and relatively low cost in relation to their nutrient value. The use of these reclaimed and recycled materials in pet food is a much more sustainable model than using human food for pets.

Matching rendered and real world images by digital image processing

Science.gov (United States)

Mitjà, Carles; Bover, Toni; Bigas, Miquel; Escofet, Jaume

2010-05-01

Recent advances in computer-generated images (CGI) have been used in commercial and industrial photography providing a broad scope in product advertising. Mixing real world images with those rendered from virtual space software shows a more or less visible mismatching between corresponding image quality performance. Rendered images are produced by software which quality performance is only limited by the resolution output. Real world images are taken with cameras with some amount of image degradation factors as lens residual aberrations, diffraction, sensor low pass anti aliasing filters, color pattern demosaicing, etc. The effect of all those image quality degradation factors can be characterized by the system Point Spread Function (PSF). Because the image is the convolution of the object by the system PSF, its characterization shows the amount of image degradation added to any taken picture. This work explores the use of image processing to degrade the rendered images following the parameters indicated by the real system PSF, attempting to match both virtual and real world image qualities. The system MTF is determined by the slanted edge method both in laboratory conditions and in the real picture environment in order to compare the influence of the working conditions on the device performance; an approximation to the system PSF is derived from the two measurements. The rendered images are filtered through a Gaussian filter obtained from the taking system PSF. Results with and without filtering are shown and compared measuring the contrast achieved in different final image regions.

Method and apparatus for imaging volume data

International Nuclear Information System (INIS)

Drebin, R.; Carpenter, L.C.

1987-01-01

An imaging system projects a two dimensional representation of three dimensional volumes where surface boundaries and objects internal to the volumes are readily shown, and hidden surfaces and the surface boundaries themselves are accurately rendered by determining volume elements or voxels. An image volume representing a volume object or data structure is written into memory. A color and opacity is assigned to each voxel within the volume and stored as a red (R), green (G), blue (B), and opacity (A) component, three dimensional data volume. The RGBA assignment for each voxel is determined based on the percentage component composition of the materials represented in the volume, and thus, the percentage of color and transparency associated with those materials. The voxels in the RGBA volume are used as mathematical filters such that each successive voxel filter is overlayed over a prior background voxel filter. Through a linear interpolation, a new background filter is determined and generated. The interpolation is successively performed for all voxels up to the front most voxel for the plane of view. The method is repeated until all display voxels are determined for the plane of view. (author)

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp

Energy Technology Data Exchange (ETDEWEB)

Bayr, S., E-mail: suvi.bayr@jyu.fi; Ojanperä, M.; Kaparaju, P.; Rintala, J.

2014-10-15

Highlights: • Rendering wastes’ mono-digestion and co-digestion with potato pulp were studied. • CSTR process with OLR of 1.5 kg VS/m{sup 3} d, HRT of 50 d was unstable in mono-digestion. • Free NH{sub 3} inhibited mono-digestion of rendering wastes. • CSTR process with OLR of 1.5 kg VS/m{sup 3} d, HRT of 50 d was stable in co-digestion. • Co-digestion increased methane yield somewhat compared to mono-digestion. - Abstract: In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55 °C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH{sub 4}-N and/or free NH{sub 3}) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m{sup 3} d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm{sup 3}/kg VS{sub fed}. On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500–680 dm{sup 3}/kg VS{sub fed}). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials.

Construction and Evaluation of an Ultra Low Latency Frameless Renderer for VR.

Science.gov (United States)

Friston, Sebastian; Steed, Anthony; Tilbury, Simon; Gaydadjiev, Georgi

2016-04-01

Latency - the delay between a user's action and the response to this action - is known to be detrimental to virtual reality. Latency is typically considered to be a discrete value characterising a delay, constant in time and space - but this characterisation is incomplete. Latency changes across the display during scan-out, and how it does so is dependent on the rendering approach used. In this study, we present an ultra-low latency real-time ray-casting renderer for virtual reality, implemented on an FPGA. Our renderer has a latency of ~1 ms from 'tracker to pixel'. Its frameless nature means that the region of the display with the lowest latency immediately follows the scan-beam. This is in contrast to frame-based systems such as those using typical GPUs, for which the latency increases as scan-out proceeds. Using a series of high and low speed videos of our system in use, we confirm its latency of ~1 ms. We examine how the renderer performs when driving a traditional sequential scan-out display on a readily available HMO, the Oculus Rift OK2. We contrast this with an equivalent apparatus built using a GPU. Using captured human head motion and a set of image quality measures, we assess the ability of these systems to faithfully recreate the stimuli of an ideal virtual reality system - one with a zero latency tracker, renderer and display running at 1 kHz. Finally, we examine the results of these quality measures, and how each rendering approach is affected by velocity of movement and display persistence. We find that our system, with a lower average latency, can more faithfully draw what the ideal virtual reality system would. Further, we find that with low display persistence, the sensitivity to velocity of both systems is lowered, but that it is much lower for ours.

Celeris: A GPU-accelerated open source software with a Boussinesq-type wave solver for real-time interactive simulation and visualization

Science.gov (United States)

Tavakkol, Sasan; Lynett, Patrick

2017-08-01

In this paper, we introduce an interactive coastal wave simulation and visualization software, called Celeris. Celeris is an open source software which needs minimum preparation to run on a Windows machine. The software solves the extended Boussinesq equations using a hybrid finite volume-finite difference method and supports moving shoreline boundaries. The simulation and visualization are performed on the GPU using Direct3D libraries, which enables the software to run faster than real-time. Celeris provides a first-of-its-kind interactive modeling platform for coastal wave applications and it supports simultaneous visualization with both photorealistic and colormapped rendering capabilities. We validate our software through comparison with three standard benchmarks for non-breaking and breaking waves.

CT two-dimensional reformation versus three-dimensional volume rendering with regard to surgical findings in the preoperative assessment of the ossicular chain in chronic suppurative otitis media

International Nuclear Information System (INIS)

Guo, Yong; Liu, Yang; Lu, Qiao-hui; Zheng, Kui-hong; Shi, Li-jing; Wang, Qing-jun

2013-01-01

Purpose: To assess the role of three-dimensional volume rendering (3DVR) in the preoperative assessment of the ossicular chain in chronic suppurative otitis media (CSOM). Materials and methods: Sixty-six patients with CSOM were included in this prospective study. Temporal bone was scanned with a 128-channel multidetector row CT and the axial data was transferred to the workstation for multiplanar reformation (MPR) and 3DVR reconstructions. Evaluation of the ossicular chain according to a three-point scoring system on two-dimensional reformation (2D) and 3DVR was performed independently by two radiologists. The evaluation results were compared with surgical findings. Results: 2D showed over 89% accuracy in the assessment of segmental absence of the ossicular chain in CSOM, no matter how small the segmental size was. 3DVR was as accurate as 2D for the assessment of segmental absence. However, 3DVR was found to be more accurate than 2D in the evaluation of partial erosion of segments. Conclusion: Both 3DVR and 2D are accurate and reliable for the assessment of the ossicular chain in CSOM. The inclusion of 3DVR images in the imaging protocol improves the accuracy of 2D in detecting ossicular erosion from CSOM

CT two-dimensional reformation versus three-dimensional volume rendering with regard to surgical findings in the preoperative assessment of the ossicular chain in chronic suppurative otitis media

Energy Technology Data Exchange (ETDEWEB)

Guo, Yong, E-mail: guoyong27@hotmail.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Liu, Yang, E-mail: liuyangdoc@sina.com [Department of Otorhinolaryngology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Lu, Qiao-hui, E-mail: Luqiaohui465@126.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Zheng, Kui-hong, E-mail: zhengkuihong1971@sina.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Shi, Li-jing, E-mail: Shilijing2003@yahoo.com.cn [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Wang, Qing-jun, E-mail: wangqingjun77@163.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China)

2013-09-15

Purpose: To assess the role of three-dimensional volume rendering (3DVR) in the preoperative assessment of the ossicular chain in chronic suppurative otitis media (CSOM). Materials and methods: Sixty-six patients with CSOM were included in this prospective study. Temporal bone was scanned with a 128-channel multidetector row CT and the axial data was transferred to the workstation for multiplanar reformation (MPR) and 3DVR reconstructions. Evaluation of the ossicular chain according to a three-point scoring system on two-dimensional reformation (2D) and 3DVR was performed independently by two radiologists. The evaluation results were compared with surgical findings. Results: 2D showed over 89% accuracy in the assessment of segmental absence of the ossicular chain in CSOM, no matter how small the segmental size was. 3DVR was as accurate as 2D for the assessment of segmental absence. However, 3DVR was found to be more accurate than 2D in the evaluation of partial erosion of segments. Conclusion: Both 3DVR and 2D are accurate and reliable for the assessment of the ossicular chain in CSOM. The inclusion of 3DVR images in the imaging protocol improves the accuracy of 2D in detecting ossicular erosion from CSOM.

The lime renderings from plaza de la Corredera, Córdoba

Directory of Open Access Journals (Sweden)

González, T.

2002-09-01

Full Text Available The causes of the pathologies found on the lime renderings from Plaza de la Corredera façades are analysed in this study. For this purpose, the mineralogical and chemical analyses of the building materials -brickwork and rendering mortar- has been carried out, as well as their physical, hydric and mechanical properties have been determined. The obtained results from both unaltered and altered materials, and the analysis of the rendering's raw materials, have allowed us to establish that rendering deterioration is connected to the presence of saline compounds (gypsum, halite, which existing in the brickwork substratum, have been removed due to the water saturation of such brickwork. The main cause responsible of the alteration forms - efflorescence, crusts, grain-disintegration, bulging, flaking found on the renderings, has been the salts precipitation (halite, hexahydrite, epsomite in their way towards the external surface.

En este estudio se analizan las causas de las patologías de los revocos de cal de las fachadas de la Plaza de la Corredera. Para ello se ha realizado el análisis mineralógico y químico de los materiales de construcción - fábrica de ladrillo y mortero de revestimiento- y se han determinado sus propiedades físicas, hídricas y mecánicas. Mediante la comparación de los resultados obtenidos en los materiales inalterados y en los alterados, así como una vez analizadas las materias primas utilizadas en la realización del revoco, se ha podido establecer que la alteración de este último está relacionada con la existencia de compuestos salinos (yeso, halita que, presentes en el substrato de fábrica de ladrillo, se han exudado por saturación de agua de la misma. La precipitación de las sales (halita, hexahidrita, epsomita en su migración hacia el exterior ha sido la principal responsable de las formas de alteración -eflorescencias, costras, arenización, abombamientos, descamaciones- que aparecen sobre los

Interactive Editing of GigaSample Terrain Fields

KAUST Repository

Treib, Marc

2012-05-01

Previous terrain rendering approaches have addressed the aspect of data compression and fast decoding for rendering, but applications where the terrain is repeatedly modified and needs to be buffered on disk have not been considered so far. Such applications require both decoding and encoding to be faster than disk transfer. We present a novel approach for editing gigasample terrain fields at interactive rates and high quality. To achieve high decoding and encoding throughput, we employ a compression scheme for height and pixel maps based on a sparse wavelet representation. On recent GPUs it can encode and decode up to 270 and 730 MPix/s of color data, respectively, at compression rates and quality superior to JPEG, and it achieves more than twice these rates for lossless height field compression. The construction and rendering of a height field triangulation is avoided by using GPU ray-casting directly on the regular grid underlying the compression scheme. We show the efficiency of our method for interactive editing and continuous level-of-detail rendering of terrain fields comprised of several hundreds of gigasamples. © 2012 The Author(s).

5-HTTLPR, anxiety and gender interaction moderates right amygdala volume in healthy subjects.

Science.gov (United States)

Cerasa, Antonio; Quattrone, Aldo; Piras, Fabrizio; Mangone, Graziella; Magariello, Angela; Fagioli, Sabrina; Girardi, Paolo; Muglia, Maria; Caltagirone, Carlo; Spalletta, Gianfranco

2014-10-01

Genetic variants within the serotonin transporter gene (5-HTTLPR) impact the neurobiology and risk for anxiety-related behaviours. There are also gender differences in the prevalence of anxiety-related behaviours. Although numerous studies have investigated the influence of 5-HTTLPR genotype on the neural systems involved in emotional regulation, none have investigated how these effects are modulated by gender and anxiety. We investigated this issue using two complementary region of interest-based structural neuroimaging approaches (voxel-based morphometry and Freesurfer) in 138 healthy individuals categorized into 'no anxiety' and 'subclinical anxiety' groups based on the Hamilton Rating Scale for Anxiety (HAM-A). Preliminarily, using anxiety as a continuous variable, we found a significant interaction effect of genotype by gender on anxiety. Females homozygous for the Short allele showed the highest HAM-A scores and males the lowest. In addition, a three-way significant interaction among genotype, gender and anxiety category was found for the right amygdala volume. Post hoc tests revealed that homozygous females carrying the Short variant with a subclinical anxiety condition had larger volume. The reported interaction effects demonstrate that gender strongly modulates the relationship between 5-HTTLPR genotype and subclinical expression of anxiety acting on amygdala, one region of the emotional neural network specifically involved in the anxiety-like behaviours. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Development of a virtual speaking simulator using Image Based Rendering.

Science.gov (United States)

Lee, J M; Kim, H; Oh, M J; Ku, J H; Jang, D P; Kim, I Y; Kim, S I

2002-01-01

The fear of speaking is often cited as the world's most common social phobia. The rapid growth of computer technology has enabled the use of virtual reality (VR) for the treatment of the fear of public speaking. There are two techniques for building virtual environments for the treatment of this fear: a model-based and a movie-based method. Both methods have the weakness that they are unrealistic and not controllable individually. To understand these disadvantages, this paper presents a virtual environment produced with Image Based Rendering (IBR) and a chroma-key simultaneously. IBR enables the creation of realistic virtual environments where the images are stitched panoramically with the photos taken from a digital camera. And the use of chroma-keys puts virtual audience members under individual control in the environment. In addition, real time capture technique is used in constructing the virtual environments enabling spoken interaction between the subject and a therapist or another subject.

Insurance of professional responsibility at medical aid rendering

Directory of Open Access Journals (Sweden)

Abyzova N.V.

2011-12-01

Full Text Available The article discusses the necessity of adoption of professional responsibility insurance act into the public health service. It is considered as the basic mechanism of compensation in case of damage to a patient at medical aid rendering

Mechanical energy yields and pressure volume and pressure time curves for whole core fuel-coolant interactions

Energy Technology Data Exchange (ETDEWEB)

Coddington, P [United Kingdom Atomic Energy Authority, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1979-10-15

In determining the damage consequences of a whole core Fuel-Coolant Interaction (FCI), one measure of the strength of a FCI that can be used and is independent of the system geometry is the constant volume mixing mechanical yield (often referred to as the Hicks-Menzies yield), which represents a near upper limit to the mechanical work of a FCI. This paper presents a recalculation of the Hicks-Menzies yields for UO{sub 2} and sodium for a range of initial fuel temperatures and fuel to coolant mass ratios, using recently published UO{sub 2} and sodium equation of state data. The work presented here takes a small number of postulated FCIs with as wide range as possible of thermal interaction parameters and determines their pressure-volume P(V) and pressure-time P(t) relations, using geometrical constraints representative of the reactor. Then by examining these P(V) and P(t) curves a representative pressure-relative volume curve or range of possible curves, for use in containment analysis, is recommended

Cement-Based Renders Manufactured with Phase-Change Materials: Applications and Feasibility

Directory of Open Access Journals (Sweden)

Luigi Coppola

2016-01-01

Full Text Available The paper focuses on the evaluation of the rheological and mechanical performances of cement-based renders manufactured with phase-change materials (PCM in form of microencapsulated paraffin for innovative and ecofriendly residential buildings. Specifically, cement-based renders were manufactured by incorporating different amount of paraffin microcapsules—ranging from 5% to 20% by weight with respect to binder. Specific mass, entrained or entrapped air, and setting time were evaluated on fresh mortars. Compressive strength was measured over time to evaluate the effect of the PCM addition on the hydration kinetics of cement. Drying shrinkage was also evaluated. Experimental results confirmed that the compressive strength decreases as the amount of PCM increases. Furthermore, the higher the PCM content, the higher the drying shrinkage. The results confirm the possibility of manufacturing cement-based renders containing up to 20% by weight of PCM microcapsules with respect to binder.

Hardware-accelerated Point Generation and Rendering of Point-based Impostors

DEFF Research Database (Denmark)

Bærentzen, Jakob Andreas

2005-01-01

This paper presents a novel scheme for generating points from triangle models. The method is fast and lends itself well to implementation using graphics hardware. The triangle to point conversion is done by rendering the models, and the rendering may be performed procedurally or by a black box API....... I describe the technique in detail and discuss how the generated point sets can easily be used as impostors for the original triangle models used to create the points. Since the points reside solely in GPU memory, these impostors are fairly efficient. Source code is available online....

The Visualization Toolkit (VTK): Rewriting the rendering code for modern graphics cards

Science.gov (United States)

Hanwell, Marcus D.; Martin, Kenneth M.; Chaudhary, Aashish; Avila, Lisa S.

2015-09-01

The Visualization Toolkit (VTK) is an open source, permissively licensed, cross-platform toolkit for scientific data processing, visualization, and data analysis. It is over two decades old, originally developed for a very different graphics card architecture. Modern graphics cards feature fully programmable, highly parallelized architectures with large core counts. VTK's rendering code was rewritten to take advantage of modern graphics cards, maintaining most of the toolkit's programming interfaces. This offers the opportunity to compare the performance of old and new rendering code on the same systems/cards. Significant improvements in rendering speeds and memory footprints mean that scientific data can be visualized in greater detail than ever before. The widespread use of VTK means that these improvements will reap significant benefits.

A new framework for interactive quality assessment with application to light field coding

Science.gov (United States)

Viola, Irene; Ebrahimi, Touradj

2017-09-01

In recent years, light field has experienced a surge of popularity, mainly due to the recent advances in acquisition and rendering technologies that have made it more accessible to the public. Thanks to image-based rendering techniques, light field contents can be rendered in real time on common 2D screens, allowing virtual navigation through the captured scenes in an interactive fashion. However, this richer representation of the scene poses the problem of reliable quality assessments for light field contents. In particular, while subjective methodologies that enable interaction have already been proposed, no work has been done on assessing how users interact with light field contents. In this paper, we propose a new framework to subjectively assess the quality of light field contents in an interactive manner and simultaneously track users behaviour. The framework is successfully used to perform subjective assessment of two coding solutions. Moreover, statistical analysis performed on the results shows interesting correlation between subjective scores and average interaction time.

PREDICTION OF THE MIXING ENTHALPIES OF BINARY LIQUID ALLOYS BY MOLECULAR INTERACTION VOLUME MODEL

Institute of Scientific and Technical Information of China (English)

H.W.Yang; D.P.Tao; Z.H.Zhou

2008-01-01

The mixing enthalpies of 23 binary liquid alloys are calculated by molecular interaction volume model (MIVM), which is a two-parameter model with the partial molar infinite dilute mixing enthalpies. The predicted values are in agreement with the experimental data and then indicate that the model is reliable and convenient.

VIDEO ANIMASI 3D PENGENALAN RUMAH ADAT DAN ALAT MUSIK KEPRI DENGAN MENGUNAKAN TEKNIK RENDER CEL-SHADING

Directory of Open Access Journals (Sweden)

Jianfranco Irfian Asnawi

2016-11-01

Full Text Available Animasi ini berjudul "video animasi 3D rumah adat dan alat musik Kepulauan Riau dengan menggunakan teknik render cel-shading" merupakan video yang bertujuan memperkenalkan alat-alat musik yang berasal dari kepulauan riau, Animasi ini akan diterapkan dengan menggunakan teknik render cel-shading. Cel-shading adalah teknik render yang menampilkan grafik 3D yang menyerupai gambar tangan, seperti gambar komik dan kartun. Teknik ini juga sudah di terapkan dalam game 3D yang ternyata menarik banyak perhatian peminat. Teknik ini akan di terapkan kedalam animasi 3D "video animasi rumah adat dan alat musik kepulauan riau dengan menggunakan teknik render cel-shading" Animasi di rancang menggunakan skenario dan storyboard kemudian di implementasikan dalam software 3D MAYA AUTODESK dengan menggunakan teknik render cel-shading. Setelah diterapkan maka di dapatkan definisi keberhasilan dari teknik render cel shading di bandingkan dengan teknik render global illumination seperti dari kecepatan dalam merender dan tingkat kecerahan warna pada video. Kata kunci: animasi, game 3D, cel-shading.

Specification and time required for the application of a lime-based render inside historic buildings

Directory of Open Access Journals (Sweden)

Vasco Peixoto de Freitas

2008-01-01

Full Text Available Intervention in ancient buildings with historical and architectural value requires traditional techniques, such as the use of lime mortars for internal and external wall renderings. In order to ensure the desired performance, these rendering mortars must be rigorously specified and quality controls have to be performed during application. The choice of mortar composition should take account of factors such as compatibility with the substrate, mechanical requirements and water behaviour. The construction schedule, which used to be considered a second order variable, nowadays plays a decisive role in the selection of the rendering technique, given its effects upon costs. How should lime-based mortars be specified? How much time is required for the application and curing of a lime-based render? This paper reflects upon the feasibility of using traditional lime mortars in three-layer renders inside churches and monasteries under adverse hygrothermal conditions and when time is critical. A case study is presented in which internal lime mortar renderings were applied in a church in Northern Portugal, where the very high relative humidity meant that several months were necessary before the drying process was complete.

ARE: Ada Rendering Engine

Directory of Open Access Journals (Sweden)

Stefano Penge

2009-10-01

Full Text Available E' ormai pratica diffusa, nello sviluppo di applicazioni web, l'utilizzo di template e di potenti template engine per automatizzare la generazione dei contenuti da presentare all'utente. Tuttavia a volte la potenza di tali engine è€ ottenuta mescolando logica e interfaccia, introducendo linguaggi diversi da quelli di descrizione della pagina, o addirittura inventando nuovi linguaggi dedicati.ARE (ADA Rendering Engine è€ pensato per gestire l'intero flusso di creazione del contenuto HTML/XHTML dinamico, la selezione del corretto template, CSS, JavaScript e la produzione dell'output separando completamente logica e interfaccia. I templates utilizzati sono puro HTML senza parti in altri linguaggi, e possono quindi essere gestiti e visualizzati autonomamente. Il codice HTML generato è€ uniforme e parametrizzato.E' composto da due moduli, CORE (Common Output Rendering Engine e ALE (ADA Layout Engine.Il primo (CORE viene utilizzato per la generazione OO degli elementi del DOM ed è pensato per aiutare lo sviluppatore nella produzione di codice valido rispetto al DTD utilizzato. CORE genera automaticamente gli elementi del DOM in base al DTD impostato nella configurazioneIl secondo (ALE viene utilizzato come template engine per selezionare automaticamente in base ad alcuni parametri (modulo, profilo utente, tipologia del nodo, del corso, preferenze di installazione il template HTML, i CSS e i file JavaScript appropriati. ALE permette di usare templates di default e microtemplates ricorsivi per semplificare il lavoro del grafico.I due moduli possono in ogni caso essere utilizzati indipendentemente l'uno dall'altro. E' possibile generare e renderizzare una pagina HTML utilizzando solo CORE oppure inviare gli oggetti CORE al template engine ALE che provvede a renderizzare la pagina HTML. Viceversa è possibile generare HTML senza utilizzare CORE ed inviarlo al template engine ALECORE è alla prima release ed è€ già utilizzato all

On the utility of 3D hand cursors to explore medical volume datasets with a touchless interface.

Science.gov (United States)

Lopes, Daniel Simões; Parreira, Pedro Duarte de Figueiredo; Paulo, Soraia Figueiredo; Nunes, Vitor; Rego, Paulo Amaral; Neves, Manuel Cassiano; Rodrigues, Pedro Silva; Jorge, Joaquim Armando

2017-08-01

Analyzing medical volume datasets requires interactive visualization so that users can extract anatomo-physiological information in real-time. Conventional volume rendering systems rely on 2D input devices, such as mice and keyboards, which are known to hamper 3D analysis as users often struggle to obtain the desired orientation that is only achieved after several attempts. In this paper, we address which 3D analysis tools are better performed with 3D hand cursors operating on a touchless interface comparatively to a 2D input devices running on a conventional WIMP interface. The main goals of this paper are to explore the capabilities of (simple) hand gestures to facilitate sterile manipulation of 3D medical data on a touchless interface, without resorting on wearables, and to evaluate the surgical feasibility of the proposed interface next to senior surgeons (N=5) and interns (N=2). To this end, we developed a touchless interface controlled via hand gestures and body postures to rapidly rotate and position medical volume images in three-dimensions, where each hand acts as an interactive 3D cursor. User studies were conducted with laypeople, while informal evaluation sessions were carried with senior surgeons, radiologists and professional biomedical engineers. Results demonstrate its usability as the proposed touchless interface improves spatial awareness and a more fluent interaction with the 3D volume than with traditional 2D input devices, as it requires lesser number of attempts to achieve the desired orientation by avoiding the composition of several cumulative rotations, which is typically necessary in WIMP interfaces. However, tasks requiring precision such as clipping plane visualization and tagging are best performed with mouse-based systems due to noise, incorrect gestures detection and problems in skeleton tracking that need to be addressed before tests in real medical environments might be performed. Copyright © 2017 Elsevier Inc. All rights reserved.

Tactile display for virtual 3D shape rendering

CERN Document Server

Mansutti, Alessandro; Bordegoni, Monica; Cugini, Umberto

2017-01-01

This book describes a novel system for the simultaneous visual and tactile rendering of product shapes which allows designers to simultaneously touch and see new product shapes during the conceptual phase of product development. This system offers important advantages, including potential cost and time savings, compared with the standard product design process in which digital 3D models and physical prototypes are often repeatedly modified until an optimal design is achieved. The system consists of a tactile display that is able to represent, within a real environment, the shape of a product. Designers can explore the rendered surface by touching curves lying on the product shape, selecting those curves that can be considered style features and evaluating their aesthetic quality. In order to physically represent these selected curves, a flexible surface is modeled by means of servo-actuated modules controlling a physical deforming strip. The tactile display is designed so as to be portable, low cost, modular,...

Differentiating aneurysm from infundibular dilatation by volume rendering MRA. Techniques for improving depiction of the posterior communicating and anterior choroidal arteries

Energy Technology Data Exchange (ETDEWEB)

Kato, Takaaki; Ito, Takeo; Hasunuma, Masahiro; Sakamoto, Yasuo; Kohama, Ikuhide; Yonemori, Terutake; Izumo, Masaki [Hakodate Shintoshi Hospital, Hokkaido (Japan)

2002-12-01

With the spread of brain dock procedures, non-invasive magnetic resonance angiography (MRA) is being utilized to broadly screen for brain blood vessel diseases. However, diagnosis of cerebral aneurysm can be difficult by routine MRA. In particular, differentiating aneurysms and infundibular dilatations (IDS) of the posterior communicating artery (PCoA) and anterior choroidal artery (AChA) at their bifurcations with the internal carotid artery (ICA) is extremely difficult and additional studies are frequently necessary. In this situation, three-dimensional computed tomography angiography (3D-CTA) and cerebral angiography have been utilized, but both techniques are invasive. Furthermore, images from cerebral angiography are only two-dimensional, and 3D-CTA requires differentiation between aneurysm and ID by observing configurational changes at the apex of the protrusion and by following gradual changes to the threshold. We therefore undertook the following steps to improve both depiction of the PCoA and AChA and differential diagnosis between aneurysm and ID: reduced slice thickness and increased number of excitations; utilized volume rendering methods to construct images; lowered thresholds for the beginning of the PCoA and AChA arteries, which represent the regions of interest. In all 11 cases that we operated on, cerebral aneurysms were diagnosed correctly and the minimum neck diameter of the cerebral aneurysm was 1.2 mm. In addition, the number of AChAs and PCoAs present in target MRA and in operational views were evaluated. In one case with an AChA aneurysm, a PCoA was not detected by target MRA, because the ICA deviated posterolaterally and pushed the PCoA to the posterior clinoid process, and blood flow was poor in operational views. In another 2 cases with AChA aneurysms, only one AChA was described in target MRA, whereas two aneurysms were present. However, one of these had a diameter less than 1 mm. In conclusion, this method offers an extremely useful aid

Differentiating aneurysm from infundibular dilatation by volume rendering MRA. Techniques for improving depiction of the posterior communicating and anterior choroidal arteries

International Nuclear Information System (INIS)

Kato, Takaaki; Ito, Takeo; Hasunuma, Masahiro; Sakamoto, Yasuo; Kohama, Ikuhide; Yonemori, Terutake; Izumo, Masaki

2002-01-01

With the spread of brain dock procedures, non-invasive magnetic resonance angiography (MRA) is being utilized to broadly screen for brain blood vessel diseases. However, diagnosis of cerebral aneurysm can be difficult by routine MRA. In particular, differentiating aneurysms and infundibular dilatations (IDS) of the posterior communicating artery (PCoA) and anterior choroidal artery (AChA) at their bifurcations with the internal carotid artery (ICA) is extremely difficult and additional studies are frequently necessary. In this situation, three-dimensional computed tomography angiography (3D-CTA) and cerebral angiography have been utilized, but both techniques are invasive. Furthermore, images from cerebral angiography are only two-dimensional, and 3D-CTA requires differentiation between aneurysm and ID by observing configurational changes at the apex of the protrusion and by following gradual changes to the threshold. We therefore undertook the following steps to improve both depiction of the PCoA and AChA and differential diagnosis between aneurysm and ID: reduced slice thickness and increased number of excitations; utilized volume rendering methods to construct images; lowered thresholds for the beginning of the PCoA and AChA arteries, which represent the regions of interest. In all 11 cases that we operated on, cerebral aneurysms were diagnosed correctly and the minimum neck diameter of the cerebral aneurysm was 1.2 mm. In addition, the number of AChAs and PCoAs present in target MRA and in operational views were evaluated. In one case with an AChA aneurysm, a PCoA was not detected by target MRA, because the ICA deviated posterolaterally and pushed the PCoA to the posterior clinoid process, and blood flow was poor in operational views. In another 2 cases with AChA aneurysms, only one AChA was described in target MRA, whereas two aneurysms were present. However, one of these had a diameter less than 1 mm. In conclusion, this method offers an extremely useful aid

Parametric model of the scala tympani for haptic-rendered cochlear implantation.

Science.gov (United States)

Todd, Catherine; Naghdy, Fazel

2005-01-01

A parametric model of the human scala tympani has been designed for use in a haptic-rendered computer simulation of cochlear implant surgery. It will be the first surgical simulator of this kind. A geometric model of the Scala Tympani has been derived from measured data for this purpose. The model is compared with two existing descriptions of the cochlear spiral. A first approximation of the basilar membrane is also produced. The structures are imported into a force-rendering software application for system development.

Radionuclide cisternography: SPECT and 3D-rendering

International Nuclear Information System (INIS)

Henkes, H.; Huber, G.; Piepgras, U.; Hierholzer, J.; Cordes, M.

1991-01-01

Radionuclide cisternography is indicated in the clinical work-up for hydrocephalus, when searching for CSF leaks, and when testing whether or not intracranial cystic lesions are communicating with the adjacent subarachnoid space. This paper demonstrates the feasibility and diagnostic value of SPECT and subsequent 3D surface rendering in addition to conventional rectilinear CSF imaging in eight patients. Planar images allowed the evaluation of CSF circulation and the detection of CSF fistula. They were advantageous in examinations 48 h after application of 111 In-DTPA. SPECT scans, generated 4-24 h after tracer application, were superior in the delineation of basal cisterns, especially in early scans; this was helpful in patients with pooling due to CSF fistula and in cystic lesions near the skull base. A major drawback was the limited image quality of delayed scans, when the SPECT data were degraded by a low count rate. 3D surface rendering was easily feasible from SPECT data and yielded high quality images. The presentation of the spatial distribution of nuclide-contaminated CSF proved especially helpful in the area of the basal cisterns. (orig.) [de

Emotion rendering in auditory simulations of imagined walking styles

DEFF Research Database (Denmark)

Turchet, Luca; Rodá, Antonio

2016-01-01

This paper investigated how different emotional states of a walker can be rendered and recognized by means of footstep sounds synthesis algorithms. In a first experiment, participants were asked to render, according to imagined walking scenarios, five emotions (aggressive, happy, neutral, sad......, and tender) by manipulating the parameters of synthetic footstep sounds simulating various combinations of surface materials and shoes types. Results allowed to identify, for the involved emotions and sound conditions, the mean values and ranges of variation of two parameters, sound level and temporal...... distance between consecutive steps. Results were in accordance with those reported in previous studies on real walking, suggesting that expression of emotions in walking is independent from the real or imagined motor activity. In a second experiment participants were asked to identify the emotions...

Transient analysis of electromagnetic wave interactions on high-contrast scatterers using volume electric field integral equation

KAUST Repository

Sayed, Sadeed Bin; Ulku, Huseyin Arda; Bagci, Hakan

2014-01-01

A marching on-in-time (MOT)-based time domain volume electric field integral equation (TD-VEFIE) solver is proposed for accurate and stable analysis of electromagnetic wave interactions on high-contrast scatterers. The stability is achieved using

Factors affecting extension workers in their rendering of effective ...

African Journals Online (AJOL)

Factors affecting extension workers in their rendering of effective service to pre and ... Small, micro and medium entrepreneurs play an important role in economic ... such as production, marketing and management to adequately service the ...

Influence of the interaction volume on the kinetic energy resolution of a velocity map imaging spectrometer

International Nuclear Information System (INIS)

Zhang Peng; Feng Zheng-Peng; Luo Si-Qiang; Wang Zhe

2016-01-01

We investigate the influence of the interaction volume on the energy resolution of a velocity map imaging spectrometer. The simulation results show that the axial interaction size has a significant influence on the resolution. This influence is increased for a higher kinetic energy. We further show that the radial interaction size has a minor influence on the energy resolution for the electron or ion with medium energy, but it is crucial for the resolution of the electron or ion with low kinetic energy. By tracing the flight trajectories we show how the electron or ion energy resolution is influenced by the interaction size. (paper)

Diagnostic accuracy of a volume-rendered computed tomography movie and other computed tomography-based imaging methods in assessment of renal vascular anatomy for laparoscopic donor nephrectomy.

Science.gov (United States)

Yamamoto, Shingo; Tanooka, Masao; Ando, Kumiko; Yamano, Toshiko; Ishikura, Reiichi; Nojima, Michio; Hirota, Shozo; Shima, Hiroki

2009-12-01

To evaluate the diagnostic accuracy of computed tomography (CT)-based imaging methods for assessing renal vascular anatomy, imaging studies, including standard axial CT, three-dimensional volume-rendered CT (3DVR-CT), and a 3DVR-CT movie, were performed on 30 patients who underwent laparoscopic donor nephrectomy (10 right side, 20 left side) for predicting the location of the renal arteries and renal, adrenal, gonadal, and lumbar veins. These findings were compared with videos obtained during the operation. Two of 37 renal arteries observed intraoperatively were missed by standard axial CT and 3DVR-CT, whereas all arteries were identified by the 3DVR-CT movie. Two of 36 renal veins were missed by standard axial CT and 3DVR-CT, whereas 1 was missed by the 3DVR-CT movie. In 20 left renal hilar anatomical structures, 20 adrenal, 20 gonadal, and 22 lumbar veins were observed during the operation. Preoperatively, the standard axial CT, 3DVR-CT, and 3DVR-CT movie detected 11, 19, and 20 adrenal veins; 13, 14, and 19 gonadal veins; and 6, 11, and 15 lumbar veins, respectively. Overall, of 135 renal vascular structures, the standard axial CT, 3DVR-CT, and 3DVR-CT movie accurately detected 99 (73.3%), 113 (83.7%), and 126 (93.3%) vessels, respectively, which indicated that the 3DVR-CT movie demonstrated a significantly higher detection rate than other CT-based imaging methods (P renal vascular anatomy before laparoscopic donor nephrectomy.

Sculpting Mountains: Interactive Terrain Modeling Based on Subsurface Geology.

Science.gov (United States)

Cordonnier, Guillaume; Cani, Marie-Paule; Benes, Bedrich; Braun, Jean; Galin, Eric

2018-05-01

Most mountain ranges are formed by the compression and folding of colliding tectonic plates. Subduction of one plate causes large-scale asymmetry while their layered composition (or stratigraphy) explains the multi-scale folded strata observed on real terrains. We introduce a novel interactive modeling technique to generate visually plausible, large scale terrains that capture these phenomena. Our method draws on both geological knowledge for consistency and on sculpting systems for user interaction. The user is provided hands-on control on the shape and motion of tectonic plates, represented using a new geologically-inspired model for the Earth crust. The model captures their volume preserving and complex folding behaviors under collision, causing mountains to grow. It generates a volumetric uplift map representing the growth rate of subsurface layers. Erosion and uplift movement are jointly simulated to generate the terrain. The stratigraphy allows us to render folded strata on eroded cliffs. We validated the usability of our sculpting interface through a user study, and compare the visual consistency of the earth crust model with geological simulation results and real terrains.

Ultrasound automated volume calculation in reproduction and in pregnancy.

Science.gov (United States)

Ata, Baris; Tulandi, Togas

2011-06-01

To review studies assessing the application of ultrasound automated volume calculation in reproductive medicine. We performed a literature search using the keywords "SonoAVC, sonography-based automated volume calculation, automated ultrasound, 3D ultrasound, antral follicle, follicle volume, follicle monitoring, follicle tracking, in vitro fertilization, controlled ovarian hyperstimulation, embryo volume, embryonic volume, gestational sac, and fetal volume" and conducted the search in PubMed, Medline, EMBASE, and the Cochrane Database of Systematic Reviews. Reference lists of identified reports were manually searched for other relevant publications. Automated volume measurements are in very good agreement with actual volumes of the assessed structures or with other validated measurement methods. The technique seems to provide reliable and highly reproducible results under a variety of conditions. Automated measurements take less time than manual measurements. Ultrasound automated volume calculation is a promising new technology which is already used in daily practice especially for assisted reproduction. Improvements to the technology will undoubtedly render it more effective and increase its use. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Interactions of glutamine dipeptides with sodium dodecyl sulfate in aqueous solution measured by volume, conductivity, and fluorescence spectra

Energy Technology Data Exchange (ETDEWEB)

Yan Zhenning, E-mail: yanzzn@zzu.edu.cn [Department of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001 (China); Sun Ximeng; Li Weiwei; Li Yu [Department of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001 (China); Wang Jianji [Department of Chemistry, Henan Normal University, Xinxiang, Henan 453007 (China)

2011-10-15

Highlights: > Ion-ion and ion-polar group interactions are dominant interactions. > The SDS addition and temperature increase cause a dehydration effect on dipeptides. > The addition of dipeptide in water decreases the c{sub cmc} of SDS. > Enthalpy-entropy compensation takes place during micellization. > Micelle aggregation number was decreased by addition of glutamine dipeptides. - Abstract: Densities, conductivities, and fluorescence spectra of {l_brace}sodium dodecyl sulfate (SDS) + glutamine dipeptide + water{r_brace} mixtures were measured as a function of temperature. The density data have been utilized to calculate apparent molar volumes, standard partial molar volumes (V{sub 2,{phi}}{sup o}), standard partial molar volumes of transfer from water to aqueous SDS solutions ({Delta}{sub t}V{sup o}), the hydration number, partial molar expansibility (E{sub {phi}}{sup o}), and Hepler's constant of glutamine dipeptides. The critical micellar concentration (c{sub cmc}) and the degree of counterion dissociation of SDS micelles obtained from electrical conductivity data have been estimated at various concentrations of glutamine dipeptide. Thermodynamic parameters of micellization of SDS in aqueous dipeptide solutions have been determined from c{sub cmc} values and an enthalpy-entropy compensation effect was observed for the ternary systems. The pyrene fluorescence spectra were used to study the change of micropolarity produced by the interaction of SDS with glutamine dipeptide, and the aggregation behavior of SDS. The results have been interpreted in terms of solute-solvent interactions and structural changes in the mixed solutions.

Validation of Thermal Lethality against Salmonella enterica in Poultry Offal during Rendering.

Science.gov (United States)

Jones-Ibarra, Amie-Marie; Acuff, Gary R; Alvarado, Christine Z; Taylor, T Matthew

2017-09-01

Recent outbreaks of human disease following contact with companion animal foods cross-contaminated with enteric pathogens, such as Salmonella enterica, have resulted in increased concern regarding the microbiological safety of animal foods. Additionally, the U.S. Food and Drug Administration Food Safety Modernization Act and its implementing rules have stipulated the implementation of current good manufacturing practices and food safety preventive controls for livestock and companion animal foods. Animal foods and feeds are sometimes formulated to include thermally rendered animal by-product meals. The objective of this research was to determine the thermal inactivation of S. enterica in poultry offal during rendering at differing temperatures. Raw poultry offal was obtained from a commercial renderer and inoculated with a mixture of Salmonella serovars Senftenberg, Enteritidis, and Gallinarum (an avian pathogen) prior to being subjected to heating at 150, 155, or 160°F (65.5, 68.3, or 71.1°C) for up to 15 min. Following heat application, surviving Salmonella bacteria were enumerated. Mean D-values for the Salmonella cocktail at 150, 155, and 160°F were 0.254 ± 0.045, 0.172 ± 0.012, and 0.086 ± 0.004 min, respectively, indicative of increasing susceptibility to increased application of heat during processing. The mean thermal process constant (z-value) was 21.948 ± 3.87°F. Results indicate that a 7.0-log-cycle inactivation of Salmonella may be obtained from the cumulative lethality encountered during the heating come-up period and subsequent rendering of raw poultry offal at temperatures not less than 150°F. Current poultry rendering procedures are anticipated to be effective for achieving necessary pathogen control when completed under sanitary conditions.

Multidetector-row computed tomography in the preoperative diagnosis of intestinal complications caused by clinically unsuspected ingested dietary foreign bodies: a case series emphasizing the use of volume rendering techniques

Energy Technology Data Exchange (ETDEWEB)

Teixeira, Augusto Cesar Vieira; Torres, Ulysses dos Santos; Oliveira, Eduardo Portela de; Gual, Fabiana; Bauab Junior, Tufik, E-mail: usantor@yahoo.com.br [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base. Serv. de Radiologia e Diagnostico por Imagem; Westin, Carlos Eduardo Garcia [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base. Cirurgia Geral; Cardoso, Luciana Vargas [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Hospital de Base. Setor de Tomografia Computadorizada

2013-11-15

Objective: the present study was aimed at describing a case series where a preoperative diagnosis of intestinal complications secondary to accidentally ingested dietary foreign bodies was made by multidetector-row computed tomography (MDCT), with emphasis on complementary findings yielded by volume rendering techniques (VRT) and curved multiplanar reconstructions (MPR). Materials and Methods: The authors retrospectively assessed five patients with surgically confirmed intestinal complications (perforation and/or obstruction) secondary to unsuspected ingested dietary foreign bodies, consecutively assisted in their institution between 2010 and 2012. Demographic, clinical, laboratory and radiological data were analyzed. VRT and curved MPR were subsequently performed. Results: preoperative diagnosis of intestinal complications was originally performed in all cases. In one case the presence of a foreign body was not initially identified as the causal factor, and the use of complementary techniques facilitated its retrospective identification. In all cases these tools allowed a better depiction of the entire foreign bodies on a single image section, contributing to the assessment of their morphology. Conclusion: although the use of complementary techniques has not had a direct impact on diagnostic performance in most cases of this series, they may provide a better depiction of foreign bodies' morphology on a single image section. (author)

The effect of depth compression on multiview rendering quality

NARCIS (Netherlands)

Merkle, P.; Morvan, Y.; Smolic, A.; Farin, D.S.; Mueller, K..; With, de P.H.N.; Wiegand, T.

2010-01-01

This paper presents a comparative study on different techniques for depth-image compression and its implications on the quality of multiview video plus depth virtual view rendering. A novel coding algorithm for depth images that concentrates on their special characteristics, namely smooth regions

Using neutrosophic graph cut segmentation algorithm for qualified rendering image selection in thyroid elastography video.

Science.gov (United States)

Guo, Yanhui; Jiang, Shuang-Quan; Sun, Baiqing; Siuly, Siuly; Şengür, Abdulkadir; Tian, Jia-Wei

2017-12-01

Recently, elastography has become very popular in clinical investigation for thyroid cancer detection and diagnosis. In elastogram, the stress results of the thyroid are displayed using pseudo colors. Due to variation of the rendering results in different frames, it is difficult for radiologists to manually select the qualified frame image quickly and efficiently. The purpose of this study is to find the qualified rendering result in the thyroid elastogram. This paper employs an efficient thyroid ultrasound image segmentation algorithm based on neutrosophic graph cut to find the qualified rendering images. Firstly, a thyroid ultrasound image is mapped into neutrosophic set, and an indeterminacy filter is constructed to reduce the indeterminacy of the spatial and intensity information in the image. A graph is defined on the image and the weight for each pixel is represented using the value after indeterminacy filtering. The segmentation results are obtained using a maximum-flow algorithm on the graph. Then the anatomic structure is identified in thyroid ultrasound image. Finally the rendering colors on these anatomic regions are extracted and validated to find the frames which satisfy the selection criteria. To test the performance of the proposed method, a thyroid elastogram dataset is built and totally 33 cases were collected. An experienced radiologist manually evaluates the selection results of the proposed method. Experimental results demonstrate that the proposed method finds the qualified rendering frame with 100% accuracy. The proposed scheme assists the radiologists to diagnose the thyroid diseases using the qualified rendering images.

Seismic design technology for breeder reactor structures. Volume 2. Special topics in soil/structure interaction analyses

International Nuclear Information System (INIS)

Reddy, D.P.

1983-04-01

This volume is divided into six chapters: definition of seismic input ground motion, review of state-of-the-art procedures, analysis guidelines, rock/structure interaction analysis example, comparison of two- and three-dimensional analyses, and comparison of analyses using FLUSH and TRI/SAC Codes

7 CFR 54.1016 - Advance information concerning service rendered.

Science.gov (United States)

2010-01-01

... MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT... rendered. Upon request of any applicant, all or any part of the contents of any report issued to the...

Ethylene signaling renders the jasmonate response of Arabidopsis insensitive to future suppression by salicylic Acid.

Science.gov (United States)

Leon-Reyes, Antonio; Du, Yujuan; Koornneef, Annemart; Proietti, Silvia; Körbes, Ana P; Memelink, Johan; Pieterse, Corné M J; Ritsema, Tita

2010-02-01

Cross-talk between jasmonate (JA), ethylene (ET), and Salicylic acid (SA) signaling is thought to operate as a mechanism to fine-tune induced defenses that are activated in response to multiple attackers. Here, 43 Arabidopsis genotypes impaired in hormone signaling or defense-related processes were screened for their ability to express SA-mediated suppression of JA-responsive gene expression. Mutant cev1, which displays constitutive expression of JA and ET responses, appeared to be insensitive to SA-mediated suppression of the JA-responsive marker genes PDF1.2 and VSP2. Accordingly, strong activation of JA and ET responses by the necrotrophic pathogens Botrytis cinerea and Alternaria brassicicola prior to SA treatment counteracted the ability of SA to suppress the JA response. Pharmacological assays, mutant analysis, and studies with the ET-signaling inhibitor 1-methylcyclopropene revealed that ET signaling renders the JA response insensitive to subsequent suppression by SA. The APETALA2/ETHYLENE RESPONSE FACTOR transcription factor ORA59, which regulates JA/ET-responsive genes such as PDF1.2, emerged as a potential mediator in this process. Collectively, our results point to a model in which simultaneous induction of the JA and ET pathway renders the plant insensitive to future SA-mediated suppression of JA-dependent defenses, which may prioritize the JA/ET pathway over the SA pathway during multi-attacker interactions.

A Single Swede Midge (Diptera: Cecidomyiidae) Larva Can Render Cauliflower Unmarketable.

Science.gov (United States)

Stratton, Chase A; Hodgdon, Elisabeth A; Zuckerman, Samuel G; Shelton, Anthony M; Chen, Yolanda H

2018-05-01

Swede midge, Contarinia nasturtii Kieffer (Diptera: Cecidomyiidae), is an invasive pest causing significant damage on Brassica crops in the Northeastern United States and Eastern Canada. Heading brassicas, like cauliflower, appear to be particularly susceptible. Swede midge is difficult to control because larvae feed concealed inside meristematic tissues of the plant. In order to develop damage and marketability thresholds necessary for integrated pest management, it is important to determine how many larvae render plants unmarketable and whether the timing of infestation affects the severity of damage. We manipulated larval density (0, 1, 3, 5, 10, or 20) per plant and the timing of infestation (30, 55, and 80 d after seeding) on cauliflower in the lab and field to answer the following questions: 1) What is the swede midge damage threshold? 2) How many swede midge larvae can render cauliflower crowns unmarketable? and 3) Does the age of cauliflower at infestation influence the severity of damage and marketability? We found that even a single larva can cause mild twisting and scarring in the crown rendering cauliflower unmarketable 52% of the time, with more larvae causing more severe damage and additional losses, regardless of cauliflower age at infestation.

Mastering Mental Ray Rendering Techniques for 3D and CAD Professionals

CERN Document Server

O'Connor, Jennifer

2010-01-01

Proven techniques for using mental ray effectively. If you're a busy artist seeking high-end results for your 3D, design, or architecture renders using mental ray, this is the perfect book for you. It distills the highly technical nature of rendering into easy-to-follow steps and tutorials that you can apply immediately to your own projects. The book uses 3ds Max and 3ds Max Design to show the integration with mental ray, but users of any 3D or CAD software can learn valuable techniques for incorporating mental ray into their pipelines.: Takes you under the hood of mental ray, a stand-alone or

NPR Lenses : Interactive Tools for Non-photorealistic Line Drawings

NARCIS (Netherlands)

Neumann, Petra; Isenberg, Tobias; Carpendale, Sheelagh

2007-01-01

NPR Lenses is an interactive technique for producing expressive non-photorealistic renderings. It provides an intuitive visual interaction tool for illustrators, allowing them to seamlessly apply a large variety of emphasis techniques. Advantages of 3D scene manipulation are combined with the

Autostereoscopic image creation by hyperview matrix controlled single pixel rendering

Science.gov (United States)

Grasnick, Armin

2017-06-01

technology just with a simple equation. This formula can be utilized to create a specific hyperview matrix for a certain 3D display - independent of the technology used. A hyperview matrix may contain the references to loads of images and act as an instruction for a subsequent rendering process of particular pixels. Naturally, a single pixel will deliver an image with no resolution and does not provide any idea of the rendered scene. However, by implementing the method of pixel recycling, a 3D image can be perceived, even if all source images are different. It will be proven that several millions of perspectives can be rendered with the support of GPU rendering and benefit from the hyperview matrix. In result, a conventional autostereoscopic display, which is designed to represent only a few perspectives can be used to show a hyperview image by using a suitable hyperview matrix. It will be shown that a millions-of-views-hyperview-image can be presented on a conventional autostereoscopic display. For such an hyperview image it is required that all pixels of the displays are allocated by different source images. Controlled by the hyperview matrix, an adapted renderer can render a full hyperview image in real-time.

Predicting the long-term durability of hemp–lime renders in inland and coastal areas using Mediterranean, Tropical and Semi-arid climatic simulations

International Nuclear Information System (INIS)

Arizzi, Anna; Viles, Heather; Martín-Sanchez, Inés; Cultrone, Giuseppe

2016-01-01

Hemp-based composites are eco-friendly building materials as they improve energy efficiency in buildings and entail low waste production and pollutant emissions during their manufacturing process. Nevertheless, the organic nature of hemp enhances the bio-receptivity of the material, with likely negative consequences for its long-term performance in the building. The main purpose of this study was to study the response at macro- and micro-scale of hemp–lime renders subjected to weathering simulations in an environmental cabinet (one year was condensed in twelve days), so as to predict their long-term durability in coastal and inland areas with Mediterranean, Tropical and Semi-arid climates, also in relation with the lime type used. The simulated climatic conditions caused almost unnoticeable mass, volume and colour changes in hemp–lime renders. No efflorescence or physical breakdown was detected in samples subjected to NaCl, because the salt mainly precipitates on the surface of samples and is washed away by the rain. Although there was no visible microbial colonisation, alkaliphilic fungi (mainly Penicillium and Aspergillus) and bacteria (mainly Bacillus and Micrococcus) were isolated in all samples. Microbial growth and diversification were higher under Tropical climate, due to heavier rainfall. The influence of the bacterial activity on the hardening of samples has also been discussed here and related with the formation and stabilisation of vaterite in hemp–lime mixes. This study has demonstrated that hemp–lime renders show good durability towards a wide range of environmental conditions and factors. However, it might be useful to take some specific preventive and maintenance measures to reduce the bio-receptivity of this material, thus ensuring a longer durability on site. - Highlights: • Realistic simulations in the cabinet of one-year exposure to environmental conditions • Influence of the lime type on the durability of hemp–lime renders �

Predicting the long-term durability of hemp–lime renders in inland and coastal areas using Mediterranean, Tropical and Semi-arid climatic simulations

Energy Technology Data Exchange (ETDEWEB)

Arizzi, Anna, E-mail: anna.arizzi@ouce.ox.ac.uk [School of Geography and the Environment, University of Oxford, Dyson Perrins Building, South Parks Road, Oxford OX1 3QY (United Kingdom); Viles, Heather [School of Geography and the Environment, University of Oxford, Dyson Perrins Building, South Parks Road, Oxford OX1 3QY (United Kingdom); Martín-Sanchez, Inés [Departamento de Microbiología, Universidad de Granada, Avda. Fuentenueva s/n, 18002 Granada (Spain); Cultrone, Giuseppe [Departamento de Mineralogía y Petrología, Universidad de Granada, Avda. Fuentenueva s/n, 18002 Granada (Spain)

2016-01-15

Hemp-based composites are eco-friendly building materials as they improve energy efficiency in buildings and entail low waste production and pollutant emissions during their manufacturing process. Nevertheless, the organic nature of hemp enhances the bio-receptivity of the material, with likely negative consequences for its long-term performance in the building. The main purpose of this study was to study the response at macro- and micro-scale of hemp–lime renders subjected to weathering simulations in an environmental cabinet (one year was condensed in twelve days), so as to predict their long-term durability in coastal and inland areas with Mediterranean, Tropical and Semi-arid climates, also in relation with the lime type used. The simulated climatic conditions caused almost unnoticeable mass, volume and colour changes in hemp–lime renders. No efflorescence or physical breakdown was detected in samples subjected to NaCl, because the salt mainly precipitates on the surface of samples and is washed away by the rain. Although there was no visible microbial colonisation, alkaliphilic fungi (mainly Penicillium and Aspergillus) and bacteria (mainly Bacillus and Micrococcus) were isolated in all samples. Microbial growth and diversification were higher under Tropical climate, due to heavier rainfall. The influence of the bacterial activity on the hardening of samples has also been discussed here and related with the formation and stabilisation of vaterite in hemp–lime mixes. This study has demonstrated that hemp–lime renders show good durability towards a wide range of environmental conditions and factors. However, it might be useful to take some specific preventive and maintenance measures to reduce the bio-receptivity of this material, thus ensuring a longer durability on site. - Highlights: • Realistic simulations in the cabinet of one-year exposure to environmental conditions • Influence of the lime type on the durability of hemp–lime renders �

Developmentally Sensitive Interaction Effects of Genes and the Social Environment on Total and Subcortical Brain Volumes.

Directory of Open Access Journals (Sweden)

Jennifer S Richards

Full Text Available Smaller total brain and subcortical volumes have been linked to psychopathology including attention-deficit/hyperactivity disorder (ADHD. Identifying mechanisms underlying these alterations, therefore, is of great importance. We investigated the role of gene-environment interactions (GxE in interindividual variability of total gray matter (GM, caudate, and putamen volumes. Brain volumes were derived from structural magnetic resonance imaging scans in participants with (N = 312 and without ADHD (N = 437 from N = 402 families (age M = 17.00, SD = 3.60. GxE effects between DAT1, 5-HTT, and DRD4 and social environments (maternal expressed warmth and criticism; positive and deviant peer affiliation as well as the possible moderating effect of age were examined using linear mixed modeling. We also tested whether findings depended on ADHD severity. Deviant peer affiliation was associated with lower caudate volume. Participants with low deviant peer affiliations had larger total GM volumes with increasing age. Likewise, developmentally sensitive GxE effects were found on total GM and putamen volume. For total GM, differential age effects were found for DAT1 9-repeat and HTTLPR L/L genotypes, depending on the amount of positive peer affiliation. For putamen volume, DRD4 7-repeat carriers and DAT1 10/10 homozygotes showed opposite age relations depending on positive peer affiliation and maternal criticism, respectively. All results were independent of ADHD severity. The presence of differential age-dependent GxE effects might explain the diverse and sometimes opposing results of environmental and genetic effects on brain volumes observed so far.

Developmentally Sensitive Interaction Effects of Genes and the Social Environment on Total and Subcortical Brain Volumes.

Science.gov (United States)

Richards, Jennifer S; Arias Vásquez, Alejandro; Franke, Barbara; Hoekstra, Pieter J; Heslenfeld, Dirk J; Oosterlaan, Jaap; Faraone, Stephen V; Buitelaar, Jan K; Hartman, Catharina A

2016-01-01

Smaller total brain and subcortical volumes have been linked to psychopathology including attention-deficit/hyperactivity disorder (ADHD). Identifying mechanisms underlying these alterations, therefore, is of great importance. We investigated the role of gene-environment interactions (GxE) in interindividual variability of total gray matter (GM), caudate, and putamen volumes. Brain volumes were derived from structural magnetic resonance imaging scans in participants with (N = 312) and without ADHD (N = 437) from N = 402 families (age M = 17.00, SD = 3.60). GxE effects between DAT1, 5-HTT, and DRD4 and social environments (maternal expressed warmth and criticism; positive and deviant peer affiliation) as well as the possible moderating effect of age were examined using linear mixed modeling. We also tested whether findings depended on ADHD severity. Deviant peer affiliation was associated with lower caudate volume. Participants with low deviant peer affiliations had larger total GM volumes with increasing age. Likewise, developmentally sensitive GxE effects were found on total GM and putamen volume. For total GM, differential age effects were found for DAT1 9-repeat and HTTLPR L/L genotypes, depending on the amount of positive peer affiliation. For putamen volume, DRD4 7-repeat carriers and DAT1 10/10 homozygotes showed opposite age relations depending on positive peer affiliation and maternal criticism, respectively. All results were independent of ADHD severity. The presence of differential age-dependent GxE effects might explain the diverse and sometimes opposing results of environmental and genetic effects on brain volumes observed so far.

Custom OpenStreetMap Rendering – OpenTrackMap Experience

Directory of Open Access Journals (Sweden)

Radek Bartoň

2010-02-01

Full Text Available After 5 years of its existence, the OpenSteetMap [1] is becoming to be an important and valuable source of a geographic data for all people on the world. Although initially targeted to provide a map of cities for routing services, it can be exploited to other and often unexpected purposes. Such an utilization is an effort to map a network of hiking tracks of the Czech Tourist Club [2].  To support and apply this endeavour, the OpenTrackMap [3] project was started. Its aim is to primarily provide a customized rendering style for Mapnik renderer which emphasizes map features important to tourists and displays a layer with hiking tracks. This article presents obstacles which such project must face and it can be used as a tutorial for other projects of similar type.

Regulated phosphorylation of the K-Cl cotransporter KCC3 is a molecular switch of intracellular potassium content and cell volume homeostasis.

Science.gov (United States)

Adragna, Norma C; Ravilla, Nagendra B; Lauf, Peter K; Begum, Gulnaz; Khanna, Arjun R; Sun, Dandan; Kahle, Kristopher T

2015-01-01

The defense of cell volume against excessive shrinkage or swelling is a requirement for cell function and organismal survival. Cell swelling triggers a coordinated homeostatic response termed regulatory volume decrease (RVD), resulting in K(+) and Cl(-) efflux via activation of K(+) channels, volume-regulated anion channels (VRACs), and the K(+)-Cl(-) cotransporters, including KCC3. Here, we show genetic alanine (Ala) substitution at threonines (Thr) 991 and 1048 in the KCC3a isoform carboxyl-terminus, preventing inhibitory phosphorylation at these sites, not only significantly up-regulates KCC3a activity up to 25-fold in normally inhibitory isotonic conditions, but is also accompanied by reversal of activity of the related bumetanide-sensitive Na(+)-K(+)-2Cl(-) cotransporter isoform 1 (NKCC1). This results in a rapid (90%) reduction in intracellular K(+) content (Ki) via both Cl-dependent (KCC3a + NKCC1) and Cl-independent [DCPIB (VRAC inhibitor)-sensitive] pathways, which collectively renders cells less prone to acute swelling in hypotonic osmotic stress. Together, these data demonstrate the phosphorylation state of Thr991/Thr1048 in KCC3a encodes a potent switch of transporter activity, Ki homeostasis, and cell volume regulation, and reveal novel observations into the functional interaction among ion transport molecules involved in RVD.

Field Operations and Enforcement Manual for Air Pollution Control. Volume III: Inspection Procedures for Specific Industries.

Science.gov (United States)

Weisburd, Melvin I.

The Field Operations and Enforcement Manual for Air Pollution Control, Volume III, explains in detail the following: inspection procedures for specific sources, kraft pulp mills, animal rendering, steel mill furnaces, coking operations, petroleum refineries, chemical plants, non-ferrous smelting and refining, foundries, cement plants, aluminum…

Parallel hierarchical radiosity rendering

Energy Technology Data Exchange (ETDEWEB)

Carter, Michael [Iowa State Univ., Ames, IA (United States)

1993-07-01

In this dissertation, the step-by-step development of a scalable parallel hierarchical radiosity renderer is documented. First, a new look is taken at the traditional radiosity equation, and a new form is presented in which the matrix of linear system coefficients is transformed into a symmetric matrix, thereby simplifying the problem and enabling a new solution technique to be applied. Next, the state-of-the-art hierarchical radiosity methods are examined for their suitability to parallel implementation, and scalability. Significant enhancements are also discovered which both improve their theoretical foundations and improve the images they generate. The resultant hierarchical radiosity algorithm is then examined for sources of parallelism, and for an architectural mapping. Several architectural mappings are discussed. A few key algorithmic changes are suggested during the process of making the algorithm parallel. Next, the performance, efficiency, and scalability of the algorithm are analyzed. The dissertation closes with a discussion of several ideas which have the potential to further enhance the hierarchical radiosity method, or provide an entirely new forum for the application of hierarchical methods.

Stereoscopy in diagnostic radiology and procedure planning: does stereoscopic assessment of volume-rendered CT angiograms lead to more accurate characterisation of cerebral aneurysms compared with traditional monoscopic viewing?

International Nuclear Information System (INIS)

Stewart, Nikolas; Lock, Gregory; Coucher, John; Hopcraft, Anthony

2014-01-01

Stereoscopic vision is a critical part of the human visual system, conveying more information than two-dimensional, monoscopic observation alone. This study aimed to quantify the contribution of stereoscopy in assessment of radiographic data, using widely available three-dimensional (3D)-capable display monitors by assessing whether stereoscopic viewing improved the characterisation of cerebral aneurysms. Nine radiology registrars were shown 40 different volume-rendered (VR) models of cerebral computed tomography angiograms (CTAs), each in both monoscopic and stereoscopic format and then asked to record aneurysm characteristics on short multiple-choice answer sheets. The monitor used was a current model commercially available 3D television. Responses were marked against a gold standard of assessments made by a consultant radiologist, using the original CT planar images on a diagnostic radiology computer workstation. The participants' results were fairly homogenous, with most showing no difference in diagnosis using stereoscopic VR models. One participant performed better on the monoscopic VR models. On average, monoscopic VRs achieved a slightly better diagnosis by 2.0%. Stereoscopy has a long history, but it has only recently become technically feasible for stored cross-sectional data to be adequately reformatted and displayed in this format. Scant literature exists to quantify the technology's possible contribution to medical imaging - this study attempts to build on this limited knowledge base and promote discussion within the field. Stereoscopic viewing of images should be further investigated and may well eventually find a permanent place in procedural and diagnostic medical imaging.

3D-shaded surface rendering of gadolinium-enhanced MR angiography in congenital heart disease

International Nuclear Information System (INIS)

Okuda, S.; Kikinis, R.; Dumanli, H.; Geva, T.; Powell, A.J.; Chung, T.

2000-01-01

Background. Gadolinium-enhanced three-dimensional (3D) MR angiography is a useful imaging technique for patients with congenital heart disease. Objective. This study sought to determine the added value of creating 3D shaded surface displays compared to standard maximal intensity projection (MIP) and multiplanar reformatting (MPR) techniques when analyzing 3D MR angiography data. Materials and methods. Seventeen patients (range, 3 months to 51 years old) with a variety of congenital cardiovascular defects underwent gadolinium-enhanced 3D MR angiography of the thorax. Color-coded 3D shaded surface models were rendered from the image data using manual segmentation and computer-based algorithms. Models could be rotated, translocated, or zoomed interactively by the viewer. Information available from the 3D models was compared to analysis based on viewing standard MIP/MPR displays. Results. Median postprocessing time for the 3D models was 6 h (range, 3-25 h) compared to approximately 20 min for MIP/MPR viewing. No additional diagnostic information was gained from 3D model analysis. All major findings with MIP/MPR postprocessing were also apparent on the 3D models. Qualitatively, the 3D models were more easily interpreted and enabled adjacent vessels to be distinguished more readily. Conclusion. Routine use of 3D shaded surface reconstructions for visualization of contrast enhanced MR angiography in congenital heart disease cannot be recommended. 3D surface rendering may be more useful for presenting complex anatomy to an audience unfamiliar with congenital heart disease and as an educational tool. (orig.)

A virtual reality solution for evaluation of radiotherapy plans

DEFF Research Database (Denmark)

Patel, Daniel; Muren, Ludvig; Mehus, Anfinn

2007-01-01

This report presents a VR system for evaluation of treatment plans used in radiotherapy (RT), developed to improve the understanding of the spatial relationships between the patient anatomy and the calculated dose distribution. The VR system offers visualization through interactive volume rendering...... of RT dose distribution and computed tomography (CT) and surface and line rendering of RT structures such as target volumes and organs at risk. The VR system has been installed and networked in a hospital room used for the daily RT conferences, making stereoscopic viewing of treatment planning data...

A virtual reality solution for evaluation of radiotherapy plans

International Nuclear Information System (INIS)

Patel, Daniel; Muren, Ludvig Paul; Mehus, Anfinn; Kvinnsland, Yngve; Ulvang, Dag Magne; Villanger, Kare P.

2007-01-01

This report presents a VR system for evaluation of treatment plans used in radiotherapy (RT), developed to improve the understanding of the spatial relationships between the patient anatomy and the calculated dose distribution. The VR system offers visualization through interactive volume rendering of RT dose distribution and computed tomography (CT) and surface and line rendering of RT structures such as target volumes and organs at risk. The VR system has been installed and networked in a hospital room used for the daily RT conferences, making stereoscopic viewing of treatment planning data for clinical cases possible

VIDEO ANIMASI 3D PENGENALAN RUMAH ADAT DAN ALAT MUSIK KEPRI DENGAN MENGUNAKAN TEKNIK RENDER CEL-SHADING

OpenAIRE

Jianfranco Irfian Asnawi; Afdhol Dzikri

2016-01-01

Animasi ini berjudul "video animasi 3D rumah adat dan alat musik Kepulauan Riau dengan menggunakan teknik render cel-shading" merupakan video yang bertujuan memperkenalkan alat-alat musik yang berasal dari kepulauan riau, Animasi ini akan diterapkan dengan menggunakan teknik render cel-shading. Cel-shading adalah teknik render yang menampilkan grafik 3D yang menyerupai gambar tangan, seperti gambar komik dan kartun. Teknik ini juga sudah di terapkan dalam game 3D yang ternyata menarik banyak ...

Subsurface Scattering-Based Object Rendering Techniques for Real-Time Smartphone Games

Directory of Open Access Journals (Sweden)

Won-Sun Lee

2014-01-01

Full Text Available Subsurface scattering that simulates the path of a light through the material in a scene is one of the advanced rendering techniques in the field of computer graphics society. Since it takes a number of long operations, it cannot be easily implemented in real-time smartphone games. In this paper, we propose a subsurface scattering-based object rendering technique that is optimized for smartphone games. We employ our subsurface scattering method that is utilized for a real-time smartphone game. And an example game is designed to validate how the proposed method can be operated seamlessly in real time. Finally, we show the comparison results between bidirectional reflectance distribution function, bidirectional scattering distribution function, and our proposed subsurface scattering method on a smartphone game.

Style grammars for interactive visualization of architecture.

Science.gov (United States)

Aliaga, Daniel G; Rosen, Paul A; Bekins, Daniel R

2007-01-01

Interactive visualization of architecture provides a way to quickly visualize existing or novel buildings and structures. Such applications require both fast rendering and an effortless input regimen for creating and changing architecture using high-level editing operations that automatically fill in the necessary details. Procedural modeling and synthesis is a powerful paradigm that yields high data amplification and can be coupled with fast-rendering techniques to quickly generate plausible details of a scene without much or any user interaction. Previously, forward generating procedural methods have been proposed where a procedure is explicitly created to generate particular content. In this paper, we present our work in inverse procedural modeling of buildings and describe how to use an extracted repertoire of building grammars to facilitate the visualization and quick modification of architectural structures and buildings. We demonstrate an interactive application where the user draws simple building blocks and, using our system, can automatically complete the building "in the style of" other buildings using view-dependent texture mapping or nonphotorealistic rendering techniques. Our system supports an arbitrary number of building grammars created from user subdivided building models and captured photographs. Using only edit, copy, and paste metaphors, the entire building styles can be altered and transferred from one building to another in a few operations, enhancing the ability to modify an existing architectural structure or to visualize a novel building in the style of the others.

Raman Line Imaging of Poly(ε-caprolactone)/Carbon Dioxide Solutions at High Pressures: A Combined Experimental and Computational Study for Interpreting Intermolecular Interactions and Free-Volume Effects.

Science.gov (United States)

Pastore Carbone, Maria Giovanna; Musto, Pellegrino; Pannico, Marianna; Braeuer, Andreas; Scherillo, Giuseppe; Mensitieri, Giuseppe; Di Maio, Ernesto

2016-09-01

In the present study, a Raman line-imaging setup was employed to monitor in situ the CO2 sorption at elevated pressures (from 0.62 to 7.10 MPa) in molten PCL. The method allowed the quantitative measurement of gas concentration in both the time-resolved and the space-resolved modes. The combined experimental and theoretical approach allowed a molecular level characterization of the system. The dissolved CO2 was found to occupy a volume essentially coincident with its van der Waals volume and the estimated partial molar volume of the probe did not change with pressure. Lewis acid-Lewis base interactions with the PCL carbonyls was confirmed to be the main interaction mechanism. The geometry of the supramolecular complex and the preferential interaction site were controlled more by steric than electronic effects. On the basis of the indications emerging from Raman spectroscopy, an equation of state thermodynamic model for the PCL-CO2 system, based upon a compressible lattice fluid theory endowed with specific interactions, has been tailored to account for the interaction types detected spectroscopically. The predictions of the thermodynamic model in terms of molar volume of solution have been compared with available volumetric measurements while predictions for CO2 partial molar volume have been compared with the values estimated on the basis of Raman spectroscopy.

Moisture Transfer through Facades Covered with Organic Binder Renders

Directory of Open Access Journals (Sweden)

Carmen DICO

2013-07-01

Full Text Available Year after year we witness the negative effect of water over buildings, caused by direct or indirect actions. This situation is obvious in case of old, historical building, subjected to this aggression for a long period of time, but new buildings are also affected. Moisture in building materials causes not only structural damage, but also reduces the thermal insulation capacity of building components.Materials like plasters or paints have been used historically for a long period of time, fulfilling two basics functions: Decoration and Protection. The most acute demands are made on exterior plasters, as they, besides being an important decorative element for the facade, must perform two different functions simultaneously: protect the substrate against weathering and moisture without sealing, providing it a certain ability to “breathe” (Heilen, 2005. In order to accomplish this aim, the first step is to understand the hygrothermal behavior of coating and substrate and define the fundamental principles of moisture transfer; According to Künzel’s Facade Protection Theory, two material properties play the most important role: Water absorption and Vapor permeability.In the context of recently adoption (2009 of the “harmonized” European standard EN 15824 – „Specifications for external renders and internal plasters based on organic binders”, this paper deals extensively with the interaction of the two mentioned above properties for the coating materials, covered by EN 15824.

Rendering LGBTQ+ Visible in Nursing: Embodying the Philosophy of Caring Science.

Science.gov (United States)

Goldberg, Lisa; Rosenburg, Neal; Watson, Jean

2017-06-01

Although health care institutions continue to address the importance of diversity initiatives, the standard(s) for treatment remain historically and institutionally grounded in a sociocultural privileging of heterosexuality. As a result, lesbian, gay, bisexual, transgender, and queer (LGBTQ+) communities in health care remain largely invisible. This marked invisibility serves as a call to action, a renaissance of thinking within redefined boundaries and limitations. We must therefore refocus our habits of attention on the wholeness of persons and the diversity of their storied experiences as embodied through contemporary society. By rethinking current understandings of LGBTQ+ identities through innovative representation(s) of the media, music industry, and pop culture within a caring science philosophy, nurses have a transformative opportunity to render LGBTQ+ visible and in turn render a transformative opportunity for themselves.

The Peshitta Rendering of Psalm 25: Spelling, Synonyms, and Syntax’

NARCIS (Netherlands)

Dyk, J.W.; Loopstra, J.; Sokoloff, M.

2013-01-01

The very act of making a translation implies that the rendered text will differ from the source text. The underlying presupposition is that the grammar, syntax, and semantics of the source and target languages are sufficiently divergent as to warrant a translation. Translations differ in how close

Analysis of electromagnetic wave interactions on nonlinear scatterers using time domain volume integral equations

KAUST Repository

Ulku, Huseyin Arda; Sayed, Sadeed Bin; Bagci, Hakan

2014-01-01

solvers are the method of choice when it comes simulating these nonlinear effects. Oftentimes, finite difference time domain (FDTD) method is used for this purpose. This is simply due to the fact that explicitness of the FDTD renders the implementation

Comparison of three methods for registration of abdominal/pelvic volume data sets from functional-anatomic scans

Science.gov (United States)

Mahmoud, Faaiza; Ton, Anthony; Crafoord, Joakim; Kramer, Elissa L.; Maguire, Gerald Q., Jr.; Noz, Marilyn E.; Zeleznik, Michael P.

2000-06-01

The purpose of this work was to evaluate three volumetric registration methods in terms of technique, user-friendliness and time requirements. CT and SPECT data from 11 patients were interactively registered using: a 3D method involving only affine transformation; a mixed 3D - 2D non-affine (warping) method; and a 3D non-affine (warping) method. In the first method representative isosurfaces are generated from the anatomical images. Registration proceeds through translation, rotation, and scaling in all three space variables. Resulting isosurfaces are fused and quantitative measurements are possible. In the second method, the 3D volumes are rendered co-planar by performing an oblique projection. Corresponding landmark pairs are chosen on matching axial slice sets. A polynomial warp is then applied. This method has undergone extensive validation and was used to evaluate the results. The third method employs visualization tools. The data model allows images to be localized within two separate volumes. Landmarks are chosen on separate slices. Polynomial warping coefficients are generated and data points from one volume are moved to the corresponding new positions. The two landmark methods were the least time consuming (10 to 30 minutes from start to finish), but did demand a good knowledge of anatomy. The affine method was tedious and required a fair understanding of 3D geometry.

Interaction between BDNF rs6265 Met allele and low family cohesion is associated with smaller left hippocampal volume in pediatric bipolar disorder.

Science.gov (United States)

Zeni, Cristian Patrick; Mwangi, Benson; Cao, Bo; Hasan, Khader M; Walss-Bass, Consuelo; Zunta-Soares, Giovana; Soares, Jair C

2016-01-01

Genetic and environmental factors are implicated in the onset and evolution of pediatric bipolar disorder, and may be associated to structural brain abnormalities. The aim of our study was to assess the impact of the interaction between the Brain-Derived Neurotrophic Factor (BDNF) rs6265 polymorphism and family functioning on hippocampal volumes of children and adolescents with bipolar disorder, and typically-developing controls. We evaluated the family functioning cohesion subscale using the Family Environment Scale-Revised, genotyped the BDNF rs6265 polymorphism, and performed structural brain imaging in 29 children and adolescents with bipolar disorder, and 22 healthy controls. We did not find significant differences between patients with BD or controls in left or right hippocampus volume (p=0.44, and p=0.71, respectively). However, we detected a significant interaction between low scores on the cohesion subscale and the presence of the Met allele at BNDF on left hippocampal volume of patients with bipolar disorder (F=3.4, p=0.043). None of the factors independently (BDNF Val66Met, cohesion scores) was significantly associated with hippocampal volume differences. small sample size, cross-sectional study. These results may lead to a better understanding of the impact of the interaction between genes and environment factors on brain structures associated to bipolar disorder and its manifestations. Copyright © 2015 Elsevier B.V. All rights reserved.

Coronary Artery Calcium Volume and Density: Potential Interactions and Overall Predictive Value: The Multi-Ethnic Study of Atherosclerosis.

Science.gov (United States)

Criqui, Michael H; Knox, Jessica B; Denenberg, Julie O; Forbang, Nketi I; McClelland, Robyn L; Novotny, Thomas E; Sandfort, Veit; Waalen, Jill; Blaha, Michael J; Allison, Matthew A

2017-08-01

This study sought to determine the possibility of interactions between coronary artery calcium (CAC) volume or CAC density with each other, and with age, sex, ethnicity, the new atherosclerotic cardiovascular disease (ASCVD) risk score, diabetes status, and renal function by estimated glomerular filtration rate, and, using differing CAC scores, to determine the improvement over the ASCVD risk score in risk prediction and reclassification. In MESA (Multi-Ethnic Study of Atherosclerosis), CAC volume was positively and CAC density inversely associated with cardiovascular disease (CVD) events. A total of 3,398 MESA participants free of clinical CVD but with prevalent CAC at baseline were followed for incident CVD events. During a median 11.0 years of follow-up, there were 390 CVD events, 264 of which were coronary heart disease (CHD). With each SD increase of ln CAC volume (1.62), risk of CHD increased 73% (p present). In multivariable Cox models, significant interactions were present for CAC volume with age and ASCVD risk score for both CHD and CVD, and CAC density with ASCVD risk score for CVD. Hazard ratios were generally stronger in the lower risk groups. Receiver-operating characteristic area under the curve and Net Reclassification Index analyses showed better prediction by CAC volume than by Agatston, and the addition of CAC density to CAC volume further significantly improved prediction. The inverse association between CAC density and incident CHD and CVD events is robust across strata of other CVD risk factors. Added to the ASCVD risk score, CAC volume and density provided the strongest prediction for CHD and CVD events, and the highest correct reclassification. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Physically Based Rendering in the Nightshade NG Visualization Platform

Science.gov (United States)

Berglund, Karrie; Larey-Williams, Trystan; Spearman, Rob; Bogard, Arthur

2015-01-01

This poster describes our work on creating a physically based rendering model in Nightshade NG planetarium simulation and visualization software (project website: NightshadeSoftware.org). We discuss techniques used for rendering realistic scenes in the universe and dealing with astronomical distances in real time on consumer hardware. We also discuss some of the challenges of rewriting the software from scratch, a project which began in 2011.Nightshade NG can be a powerful tool for sharing data and visualizations. The desktop version of the software is free for anyone to download, use, and modify; it runs on Windows and Linux (and eventually Mac). If you are looking to disseminate your data or models, please stop by to discuss how we can work together.Nightshade software is used in literally hundreds of digital planetarium systems worldwide. Countless teachers and astronomy education groups run the software on flat screens. This wide use makes Nightshade an effective tool for dissemination to educators and the public.Nightshade NG is an especially powerful visualization tool when projected on a dome. We invite everyone to enter our inflatable dome in the exhibit hall to see this software in a 3D environment.

Digital representations of the real world how to capture, model, and render visual reality

CERN Document Server

Magnor, Marcus A; Sorkine-Hornung, Olga; Theobalt, Christian

2015-01-01

Create Genuine Visual Realism in Computer Graphics Digital Representations of the Real World: How to Capture, Model, and Render Visual Reality explains how to portray visual worlds with a high degree of realism using the latest video acquisition technology, computer graphics methods, and computer vision algorithms. It explores the integration of new capture modalities, reconstruction approaches, and visual perception into the computer graphics pipeline.Understand the Entire Pipeline from Acquisition, Reconstruction, and Modeling to Realistic Rendering and ApplicationsThe book covers sensors fo

Towards the Availability of the Distributed Cluster Rendering System: Automatic Modeling and Verification

DEFF Research Database (Denmark)

Wang, Kemin; Jiang, Zhengtao; Wang, Yongbin

2012-01-01

, whenever the number of node-n and related parameters vary, we can create the PRISM model file rapidly and then we can use PRISM model checker to verify ralated system properties. At the end of this study, we analyzed and verified the availability distributions of the Distributed Cluster Rendering System......In this study, we proposed a Continuous Time Markov Chain Model towards the availability of n-node clusters of Distributed Rendering System. It's an infinite one, we formalized it, based on the model, we implemented a software, which can automatically model with PRISM language. With the tool...

Flight-appropriate 3D Terrain-rendering Toolkit for Synthetic Vision, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The TerraBlocksTM 3D terrain data format and terrain-block-rendering methodology provides an enabling basis for successful commercial deployment of...

Skype me! Socially Contingent Interactions Help Toddlers Learn Language

OpenAIRE

Roseberry, Sarah; Hirsh-Pasek, Kathy; Golinkoff, Roberta Michnick

2013-01-01

Language learning takes place in the context of social interactions, yet the mechanisms that render social interactions useful for learning language remain unclear. This paper focuses on whether social contingency might support word learning. Toddlers aged 24- to 30-months (N=36) were exposed to novel verbs in one of three conditions: live interaction training, socially contingent video training over video chat, and non-contingent video training (yoked video). Results sugges...

Predicting the long-term durability of hemp-lime renders in inland and coastal areas using Mediterranean, Tropical and Semi-arid climatic simulations.

Science.gov (United States)

Arizzi, Anna; Viles, Heather; Martín-Sanchez, Inés; Cultrone, Giuseppe

2016-01-15

Hemp-based composites are eco-friendly building materials as they improve energy efficiency in buildings and entail low waste production and pollutant emissions during their manufacturing process. Nevertheless, the organic nature of hemp enhances the bio-receptivity of the material, with likely negative consequences for its long-term performance in the building. The main purpose of this study was to study the response at macro- and micro-scale of hemp-lime renders subjected to weathering simulations in an environmental cabinet (one year was condensed in twelve days), so as to predict their long-term durability in coastal and inland areas with Mediterranean, Tropical and Semi-arid climates, also in relation with the lime type used. The simulated climatic conditions caused almost unnoticeable mass, volume and colour changes in hemp-lime renders. No efflorescence or physical breakdown was detected in samples subjected to NaCl, because the salt mainly precipitates on the surface of samples and is washed away by the rain. Although there was no visible microbial colonisation, alkaliphilic fungi (mainly Penicillium and Aspergillus) and bacteria (mainly Bacillus and Micrococcus) were isolated in all samples. Microbial growth and diversification were higher under Tropical climate, due to heavier rainfall. The influence of the bacterial activity on the hardening of samples has also been discussed here and related with the formation and stabilisation of vaterite in hemp-lime mixes. This study has demonstrated that hemp-lime renders show good durability towards a wide range of environmental conditions and factors. However, it might be useful to take some specific preventive and maintenance measures to reduce the bio-receptivity of this material, thus ensuring a longer durability on site. Copyright © 2015 Elsevier B.V. All rights reserved.

Deep Exemplar 2D-3D Detection by Adapting from Real to Rendered Views

OpenAIRE

Massa, Francisco; Russell, Bryan; Aubry, Mathieu

2015-01-01

This paper presents an end-to-end convolutional neural network (CNN) for 2D-3D exemplar detection. We demonstrate that the ability to adapt the features of natural images to better align with those of CAD rendered views is critical to the success of our technique. We show that the adaptation can be learned by compositing rendered views of textured object models on natural images. Our approach can be naturally incorporated into a CNN detection pipeline and extends the accuracy and speed benefi...

Shape Displays: Spatial Interaction with Dynamic Physical Form.

Science.gov (United States)

Leithinger, Daniel; Follmer, Sean; Olwal, Alex; Ishii, Hiroshi

2015-01-01

Shape displays are an emerging class of devices that emphasize actuation to enable rich physical interaction, complementing concepts in virtual and augmented reality. The ability to render form introduces new opportunities to touch, grasp, and manipulate dynamic physical content and tangible objects, in both nearby and remote environments. This article presents novel hardware, interaction techniques, and applications, which point to the potential for extending the ways that we traditionally interact with the physical world, empowered by digital computation.

Rendering of HDR content on LDR displays: an objective approach

Science.gov (United States)

Krasula, Lukáš; Narwaria, Manish; Fliegel, Karel; Le Callet, Patrick

2015-09-01

Dynamic range compression (or tone mapping) of HDR content is an essential step towards rendering it on traditional LDR displays in a meaningful way. This is however non-trivial and one of the reasons is that tone mapping operators (TMOs) usually need content-specific parameters to achieve the said goal. While subjective TMO parameter adjustment is the most accurate, it may not be easily deployable in many practical applications. Its subjective nature can also influence the comparison of different operators. Thus, there is a need for objective TMO parameter selection to automate the rendering process. To that end, we investigate into a new objective method for TMO parameters optimization. Our method is based on quantification of contrast reversal and naturalness. As an important advantage, it does not require any prior knowledge about the input HDR image and works independently on the used TMO. Experimental results using a variety of HDR images and several popular TMOs demonstrate the value of our method in comparison to default TMO parameter settings.

Unconscious neural processing differs with method used to render stimuli invisible

Directory of Open Access Journals (Sweden)

Sergey Victor Fogelson

2014-06-01

Full Text Available Visual stimuli can be kept from awareness using various methods. The extent of processing that a given stimulus receives in the absence of awareness is typically used to make claims about the role of consciousness more generally. The neural processing elicited by a stimulus, however, may also depend on the method used to keep it from awareness, and not only on whether the stimulus reaches awareness. Here we report that the method used to render an image invisible has a dramatic effect on how category information about the unseen stimulus is encoded across the human brain. We collected fMRI data while subjects viewed images of faces and tools, that were rendered invisible using either continuous flash suppression (CFS or chromatic flicker fusion (CFF. In a third condition, we presented the same images under normal fully visible viewing conditions. We found that category information about visible images could be extracted from patterns of fMRI responses throughout areas of neocortex known to be involved in face or tool processing. However, category information about stimuli kept from awareness using CFS could be recovered exclusively within occipital cortex, whereas information about stimuli kept from awareness using CFF was also decodable within temporal and frontal regions. We conclude that unconsciously presented objects are processed differently depending on how they are rendered subjectively invisible. Caution should therefore be used in making generalizations on the basis of any one method about the neural basis of consciousness or the extent of information processing without consciousness.

Unconscious neural processing differs with method used to render stimuli invisible.

Science.gov (United States)

Fogelson, Sergey V; Kohler, Peter J; Miller, Kevin J; Granger, Richard; Tse, Peter U

2014-01-01

Visual stimuli can be kept from awareness using various methods. The extent of processing that a given stimulus receives in the absence of awareness is typically used to make claims about the role of consciousness more generally. The neural processing elicited by a stimulus, however, may also depend on the method used to keep it from awareness, and not only on whether the stimulus reaches awareness. Here we report that the method used to render an image invisible has a dramatic effect on how category information about the unseen stimulus is encoded across the human brain. We collected fMRI data while subjects viewed images of faces and tools, that were rendered invisible using either continuous flash suppression (CFS) or chromatic flicker fusion (CFF). In a third condition, we presented the same images under normal fully visible viewing conditions. We found that category information about visible images could be extracted from patterns of fMRI responses throughout areas of neocortex known to be involved in face or tool processing. However, category information about stimuli kept from awareness using CFS could be recovered exclusively within occipital cortex, whereas information about stimuli kept from awareness using CFF was also decodable within temporal and frontal regions. We conclude that unconsciously presented objects are processed differently depending on how they are rendered subjectively invisible. Caution should therefore be used in making generalizations on the basis of any one method about the neural basis of consciousness or the extent of information processing without consciousness.

Sonic Interactions in Virtual Reality: State of the Art, Current Challenges, and Future Directions.

Science.gov (United States)

Serafin, Stefania; Geronazzo, Michele; Erkut, Cumhur; Nilsson, Niels C; Nordahl, Rolf

2018-03-01

A high-fidelity but efficient sound simulation is an essential element of any VR experience. Many of the techniques used in virtual acoustics are graphical rendering techniques suitably modified to account for sound generation and propagation. In recent years, several advances in hardware and software technologies have been facilitating the development of immersive interactive sound-rendering experiences. In this article, we present a review of the state of the art of such simulations, with a focus on the different elements that, combined, provide a complete interactive sonic experience. This includes physics-based simulation of sound effects and their propagation in space together with binaural rendering to simulate the position of sound sources. We present how these different elements of the sound design pipeline have been addressed in the literature, trying to find the trade-off between accuracy and plausibility. Recent applications and current challenges are also presented.

Software System for Vocal Rendering of Printed Documents

Directory of Open Access Journals (Sweden)

Marian DARDALA

2008-01-01

Full Text Available The objective of this paper is to present a software system architecture developed to render the printed documents in a vocal form. On the other hand, in the paper are described the software solutions that exist as software components and are necessary for documents processing as well as for multimedia device controlling used by the system. The usefulness of this system is for people with visual disabilities that can access the contents of documents without that they be printed in Braille system or to exist in an audio form.

Regulated phosphorylation of the K-Cl cotransporter KCC3 at dual C-terminal threonines is a potent switch of intracellular potassium content and cell volume homeostasis

Directory of Open Access Journals (Sweden)

Norma C. Adragna

2015-07-01

Full Text Available The defense of cell volume against excessive shrinkage or swelling is a requirement for cell function and organismal survival. Cell swelling triggers a coordinated homeostatic response termed regulatory volume decrease (RVD, resulting in K+ and Cl– efflux via the activation of K+ channels, volume-regulated anion channels (VRACs, and the K+-Cl– cotransporters, including KCC3. Here, we show genetic alanine (Ala substitution at threonines (Thr 991 and 1048 in the KCC3a isoform carboxyl-terminus, preventing inhibitory phosphorylation at these sites, not only significantly up-regulates KCC3a activity up to 25-fold in normally inhibitory isotonic conditions, but is also accompanied by reversal of activity of the related bumetanide-sensitive Na+-K+-2Cl– cotransporter isoform 1 (NKCC1. This results in a rapid (90 % reduction in intracellular K+ content (Ki via both Cl-dependent (KCC3a + NKCC1 and Cl-independent (DCPIB [VRAC inhibitor]-sensitive pathways, which collectively renders cells less prone to acute swelling in hypotonic osmotic stress. Together, these data demonstrate the phosphorylation state of Thr991/Thr1048 in the KCC3a encodes a potent switch of transporter activity, Ki homeostasis, and cell volume regulation, and reveal novel observations into the functional interaction among ion transport molecules involved in RVD.

Flight-appropriate 3D Terrain-rendering Toolkit for Synthetic Vision, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — TerraMetrics proposes an SBIR Phase I R/R&D effort to develop a key 3D terrain-rendering technology that provides the basis for successful commercial deployment...

Brain volume measurement using three-dimensional magnetic resonance images

International Nuclear Information System (INIS)

Ishimaru, Yoshihiro

1996-01-01

This study was designed to validate accurate measurement method of human brain volume using three dimensional (3D) MRI data on a workstation, and to establish optimal correcting method of human brain volume on diagnosis of brain atrophy. 3D MRI data were acquired by fast SPGR sequence using 1.5 T MR imager. 3D MRI data were segmented by region growing method and 3D image was displayed by surface rendering method on the workstation. Brain volume was measured by the volume measurement function of the workstation. In order to validate the accurate measurement method, phantoms and a specimen of human brain were examined. Phantom volume was measured by changing the lower level of threshold value. At the appropriate threshold value, percentage of error of phantoms and the specimen were within 0.6% and 0.08%, respectively. To establish the optimal correcting method, 130 normal volunteers were examined. Brain volumes corrected with height weight, body surface area, and alternative skull volume were evaluated. Brain volume index, which is defined as dividing brain volume by alternative skull volume, had the best correlation with age (r=0.624, p<0.05). No gender differences was observed in brain volume index in contrast to in brain volume. The clinical usefulness of this correcting method for brain atrophy diagnosis was evaluated in 85 patients. Diagnosis by 2D spin echo MR images was compared with brain volume index. Diagnosis of brain atrophy by 2D MR image was concordant with the evaluation by brain volume index. These results indicated that this measurement method had high accuracy, and it was important to set the appropriate threshold value. Brain volume index was the appropriate indication for evaluation of human brain volume, and was considered to be useful for the diagnosis of brain atrophy. (author)

Photometric and Colorimeric Comparison of HDR and Spctrally Resolved Rendering Images

DEFF Research Database (Denmark)

Amdemeskel, Mekbib Wubishet; Soreze, Thierry Silvio Claude; Thorseth, Anders

2017-01-01

In this paper, we will demonstrate a comparison between measured colorimetric images, and simulated images from a physics based rendering engine. The colorimetric images are high dynamic range (HDR) and taken with a luminance and colour camera mounted on a goniometer. For the comparison, we have ...

3D-TV Rendering on a Multiprocessor System on a Chip

NARCIS (Netherlands)

Van Eijndhoven, J.T.J.; Li, X.

2006-01-01

This thesis focuses on the issue of mapping 3D-TV rendering applications to a multiprocessor platform. The target platform aims to address tomorrow's multi-media consumer market. The prototype chip, called Wasabi, contains a set of TriMedia processors that communicate viaa shared memory, fast

Iso-surface volume rendering for implant surgery

NARCIS (Netherlands)

van Foreest-Timp, Sheila; Lemke, H.U.; Inamura, K.; Doi, K.; Vannier, M.W.; Farman, A.G.

2001-01-01

Many clinical situations ask for the simultaneous visualization of anatomical surfaces and synthetic meshes. Common examples include hip replacement surgery, intra-operative visualization of surgical instruments or probes, visualization of planning information, or implant surgery. To be useful for

LOD map--A visual interface for navigating multiresolution volume visualization.

Science.gov (United States)

Wang, Chaoli; Shen, Han-Wei

2006-01-01

In multiresolution volume visualization, a visual representation of level-of-detail (LOD) quality is important for us to examine, compare, and validate different LOD selection algorithms. While traditional methods rely on ultimate images for quality measurement, we introduce the LOD map--an alternative representation of LOD quality and a visual interface for navigating multiresolution data exploration. Our measure for LOD quality is based on the formulation of entropy from information theory. The measure takes into account the distortion and contribution of multiresolution data blocks. A LOD map is generated through the mapping of key LOD ingredients to a treemap representation. The ordered treemap layout is used for relative stable update of the LOD map when the view or LOD changes. This visual interface not only indicates the quality of LODs in an intuitive way, but also provides immediate suggestions for possible LOD improvement through visually-striking features. It also allows us to compare different views and perform rendering budget control. A set of interactive techniques is proposed to make the LOD adjustment a simple and easy task. We demonstrate the effectiveness and efficiency of our approach on large scientific and medical data sets.

Complex adaptation-based LDR image rendering for 3D image reconstruction

Science.gov (United States)

Lee, Sung-Hak; Kwon, Hyuk-Ju; Sohng, Kyu-Ik

2014-07-01

A low-dynamic tone-compression technique is developed for realistic image rendering that can make three-dimensional (3D) images similar to realistic scenes by overcoming brightness dimming in the 3D display mode. The 3D surround provides varying conditions for image quality, illuminant adaptation, contrast, gamma, color, sharpness, and so on. In general, gain/offset adjustment, gamma compensation, and histogram equalization have performed well in contrast compression; however, as a result of signal saturation and clipping effects, image details are removed and information is lost on bright and dark areas. Thus, an enhanced image mapping technique is proposed based on space-varying image compression. The performance of contrast compression is enhanced with complex adaptation in a 3D viewing surround combining global and local adaptation. Evaluating local image rendering in view of tone and color expression, noise reduction, and edge compensation confirms that the proposed 3D image-mapping model can compensate for the loss of image quality in the 3D mode.

Unraveling The Connectome: Visualizing and Abstracting Large-Scale Connectomics Data

KAUST Repository

Al-Awami, Ali K.

2017-01-01

-user system seamlessly integrates a diverse set of tools. Our system provides support for the management, provenance, accountability, and auditing of large-scale segmentations. Finally, we present a novel architecture to render very large volumes interactively

Customization, control, and characterization of a commercial haptic device for high-fidelity rendering of weak forces.

Science.gov (United States)

Gurari, Netta; Baud-Bovy, Gabriel

2014-09-30

The emergence of commercial haptic devices offers new research opportunities to enhance our understanding of the human sensory-motor system. Yet, commercial device capabilities have limitations which need to be addressed. This paper describes the customization of a commercial force feedback device for displaying forces with a precision that exceeds the human force perception threshold. The device was outfitted with a multi-axis force sensor and closed-loop controlled to improve its transparency. Additionally, two force sensing resistors were attached to the device to measure grip force. Force errors were modeled in the frequency- and time-domain to identify contributions from the mass, viscous friction, and Coulomb friction during open- and closed-loop control. The effect of user interaction on system stability was assessed in the context of a user study which aimed to measure force perceptual thresholds. Findings based on 15 participants demonstrate that the system maintains stability when rendering forces ranging from 0-0.20 N, with an average maximum absolute force error of 0.041 ± 0.013 N. Modeling the force errors revealed that Coulomb friction and inertia were the main contributors to force distortions during respectively slow and fast motions. Existing commercial force feedback devices cannot render forces with the required precision for certain testing scenarios. Building on existing robotics work, this paper shows how a device can be customized to make it reliable for studying the perception of weak forces. The customized and closed-loop controlled device is suitable for measuring force perceptual thresholds. Copyright © 2014 Elsevier B.V. All rights reserved.

USER EVALUATION OF EIGHT LED LIGHT SOURCES WITH DIFFERENTSPECIAL COLOUR RENDERING INDICES R9

DEFF Research Database (Denmark)

Markvart, Jakob; Iversen, Anne; Logadóttir, Ásta

2013-01-01

In this study we evaluated the influence of the special colour rendering index R9 on subjective red colour perception and Caucasian skin appearance among untrained test subjects. The light sources tested are commercially available LED based light sources with similar correlated colour temperature...... and general colour rendering index, but with varying R9. It was found that the test subjects in general are more positive towards light sources with higher R9. The shift from a majority of negative responses to a majority of positive responses is found to occur at R9 values of ~20....

Acidic precipitation. Volume 3: Sources, deposition, and canopy interactions. Advances in environmental science

Energy Technology Data Exchange (ETDEWEB)

Lindberg, S.E.; Page, A.L.; Norton, S.A. (eds.)

1990-01-01

As has been the case with many environmental issues of the twentieth century, acidic precipitation has its origin in emissions to the atmosphere of numerous compounds from both natural and man-made sources. This volume emphasizes the atmospheric aspects of acidic precipitation and all that this term has come to include (e.g. toxic gases such as ozone, trace metals, aluminum, and oxides of nitrogen). It progresses from emissions of the precursors of acidic precipitation to their eventual deposition on environmental surfaces. The chapters describe the sources of acidic and basic airborne substances, their interactions in the atmosphere and with rain droplets, and their reactions with other airborne constituents such as aluminum and other metals. Also discussed are the use of metals as tracers of sources of the precursors of acidic precipitation and as tracers of historical deposition rates, the processes controlling the removal of airborne material as dry deposition and deposition interactions with the forest canopy, and past and future trends in atmospheric emissions and options for their abatement.

Genetically determined interaction between the dopamine transporter and the D2 receptor on prefronto-striatal activity and volume in humans.

Science.gov (United States)

Bertolino, Alessandro; Fazio, Leonardo; Di Giorgio, Annabella; Blasi, Giuseppe; Romano, Raffaella; Taurisano, Paolo; Caforio, Grazia; Sinibaldi, Lorenzo; Ursini, Gianluca; Popolizio, Teresa; Tirotta, Emanuele; Papp, Audrey; Dallapiccola, Bruno; Borrelli, Emiliana; Sadee, Wolfgang

2009-01-28

Dopamine modulation of neuronal activity during memory tasks identifies a nonlinear inverted-U shaped function. Both the dopamine transporter (DAT) and dopamine D(2) receptors (encoded by DRD(2)) critically regulate dopamine signaling in the striatum and in prefrontal cortex during memory. Moreover, in vitro studies have demonstrated that DAT and D(2) proteins reciprocally regulate each other presynaptically. Therefore, we have evaluated the genetic interaction between a DRD(2) polymorphism (rs1076560) causing reduced presynaptic D(2) receptor expression and the DAT 3'-VNTR variant (affecting DAT expression) in a large sample of healthy subjects undergoing blood oxygenation level-dependent (BOLD)-functional magnetic resonance imaging (MRI) during memory tasks and structural MRI. Results indicated a significant DRD(2)/DAT interaction in prefrontal cortex and striatum BOLD activity during both working memory and encoding of recognition memory. The differential effect on BOLD activity of the DAT variant was mostly manifest in the context of the DRD(2) allele associated with lower presynaptic expression. Similar results were also evident for gray matter volume in caudate. These interactions describe a nonlinear relationship between compound genotypes and brain activity or gray matter volume. Complementary data from striatal protein extracts from wild-type and D(2) knock-out animals (D2R(-/-)) indicate that DAT and D(2) proteins interact in vivo. Together, our results demonstrate that the interaction between genetic variants in DRD(2) and DAT critically modulates the nonlinear relationship between dopamine and neuronal activity during memory processing.

Conservation of the historical render in the Church of Nossa Senhora da Assunção in Elvas

Directory of Open Access Journals (Sweden)

Sofia Salema

2008-01-01

Full Text Available In this paper we present a practical case of conservation of the historical renders in the pyramidal tower of the Church of Nossa Senhora da Assunção in Elvas (Portugal, carried out by the former IPPAR (Portuguese Institute of Architectonic Heritage, now Regional Direction of Culture of Alentejo. Awareness of the value and of the risks facing these renders points towards the necessity to safeguard their material authenticity. During the works of conservation of the main façade, under the layers of non decorated recovering render, a previous decorated render, simulating stone masonry, with raised joints reproducing stone divisions and the internal structure in solid brick, was discovered. After material and historical analysis we came to the conclusion that it was highly probable that this render was contemporary to the construction of the Church and, as such, it seemed essential to conserve and restore this covering as historical evidence and cultural heritage. Treatment of the pyramidal tower render included removal of the non original recover mortars, survey of ancient materials, execution of technical and decorative scheme, surfaces' cleaning and consolidation of the weaker original old mortars. In order to fill the gaps in the original surface, specific lime mortars, prepared with washed sand and standard grain size, were used. Restoration techniques were used to reconstitute and integrate the lacunas. These actions not only conserved the workmanship, but also reconstructed the decorative structure and a reading clarity, allowing the identification of restoration without the connotation of a mimetic integration. This joint action, only possible with the help of the conservation and restoration team, puts into evidence the possibility of continuous evaluation and learning. It is clear that, in cases where there are unknown, unpredictable factors, due to the specific work and value of the materials, it is possible to change the course

Efficient visibility-driven medical image visualisation via adaptive binned visibility histogram.

Science.gov (United States)

Jung, Younhyun; Kim, Jinman; Kumar, Ashnil; Feng, David Dagan; Fulham, Michael

2016-07-01

'Visibility' is a fundamental optical property that represents the observable, by users, proportion of the voxels in a volume during interactive volume rendering. The manipulation of this 'visibility' improves the volume rendering processes; for instance by ensuring the visibility of regions of interest (ROIs) or by guiding the identification of an optimal rendering view-point. The construction of visibility histograms (VHs), which represent the distribution of all the visibility of all voxels in the rendered volume, enables users to explore the volume with real-time feedback about occlusion patterns among spatially related structures during volume rendering manipulations. Volume rendered medical images have been a primary beneficiary of VH given the need to ensure that specific ROIs are visible relative to the surrounding structures, e.g. the visualisation of tumours that may otherwise be occluded by neighbouring structures. VH construction and its subsequent manipulations, however, are computationally expensive due to the histogram binning of the visibilities. This limits the real-time application of VH to medical images that have large intensity ranges and volume dimensions and require a large number of histogram bins. In this study, we introduce an efficient adaptive binned visibility histogram (AB-VH) in which a smaller number of histogram bins are used to represent the visibility distribution of the full VH. We adaptively bin medical images by using a cluster analysis algorithm that groups the voxels according to their intensity similarities into a smaller subset of bins while preserving the distribution of the intensity range of the original images. We increase efficiency by exploiting the parallel computation and multiple render targets (MRT) extension of the modern graphical processing units (GPUs) and this enables efficient computation of the histogram. We show the application of our method to single-modality computed tomography (CT), magnetic resonance

A two-metric proposal to specify the color-rendering properties of light sources for retail lighting

Science.gov (United States)

Freyssinier, Jean Paul; Rea, Mark

2010-08-01

Lighting plays an important role in supporting retail operations, from attracting customers, to enabling the evaluation of merchandise, to facilitating the completion of the sale. Lighting also contributes to the identity, comfort, and visual quality of a retail store. With the increasing availability and quality of white LEDs, retail lighting specifiers are now considering LED lighting in stores. The color rendering of light sources is a key factor in supporting retail lighting goals and thus influences a light source's acceptance by users and specifiers. However, there is limited information on what consumers' color preferences are, and metrics used to describe the color properties of light sources often are equivocal and fail to predict preference. The color rendering of light sources is described in the industry solely by the color rendering index (CRI), which is only indirectly related to human perception. CRI is intended to characterize the appearance of objects illuminated by the source and is increasingly being challenged because new sources are being developed with increasingly exotic spectral power distributions. This paper discusses how CRI might be augmented to better use it in support of the design objectives for retail merchandising. The proposed guidelines include the use of gamut area index as a complementary metric to CRI for assuring good color rendering.

Tomographic image reconstruction and rendering with texture-mapping hardware

International Nuclear Information System (INIS)

Azevedo, S.G.; Cabral, B.K.; Foran, J.

1994-07-01

The image reconstruction problem, also known as the inverse Radon transform, for x-ray computed tomography (CT) is found in numerous applications in medicine and industry. The most common algorithm used in these cases is filtered backprojection (FBP), which, while a simple procedure, is time-consuming for large images on any type of computational engine. Specially-designed, dedicated parallel processors are commonly used in medical CT scanners, whose results are then passed to graphics workstation for rendering and analysis. However, a fast direct FBP algorithm can be implemented on modern texture-mapping hardware in current high-end workstation platforms. This is done by casting the FBP algorithm as an image warping operation with summing. Texture-mapping hardware, such as that on the Silicon Graphics Reality Engine (TM), shows around 600 times speedup of backprojection over a CPU-based implementation (a 100 Mhz R4400 in this case). This technique has the further advantages of flexibility and rapid programming. In addition, the same hardware can be used for both image reconstruction and for volumetric rendering. The techniques can also be used to accelerate iterative reconstruction algorithms. The hardware architecture also allows more complex operations than straight-ray backprojection if they are required, including fan-beam, cone-beam, and curved ray paths, with little or no speed penalties

Photon Differential Splatting for Rendering Caustics

DEFF Research Database (Denmark)

Frisvad, Jeppe Revall; Schjøth, Lars; Erleben, Kenny

2014-01-01

We present a photon splatting technique which reduces noise and blur in the rendering of caustics. Blurring of illumination edges is an inherent problem in photon splatting, as each photon is unaware of its neighbours when being splatted. This means that the splat size is usually based...... on heuristics rather than knowledge of the local flux density. We use photon differentials to determine the size and shape of the splats such that we achieve adaptive anisotropic flux density estimation in photon splatting. As compared to previous work that uses photon differentials, we present the first method...... where no photons or beams or differentials need to be stored in a map. We also present improvements in the theory of photon differentials, which give more accurate results and a faster implementation. Our technique has good potential for GPU acceleration, and we limit the number of parameters requiring...

Medical review practices for driver licensing volume 2: case studies of medical referrals and licensing outcomes in Maine, Ohio, Oregon, Texas, Washington, and Wisconsin.

Science.gov (United States)

2017-03-01

This is the second of three reports examining driver medical review practices in the United States and how : they fulfill the basic functions of identifying, assessing, and rendering licensing decisions on medically at-risk : drivers. This volume pre...

Gesture Interaction Browser-Based 3D Molecular Viewer.

Science.gov (United States)

Virag, Ioan; Stoicu-Tivadar, Lăcrămioara; Crişan-Vida, Mihaela

2016-01-01

The paper presents an open source system that allows the user to interact with a 3D molecular viewer using associated hand gestures for rotating, scaling and panning the rendered model. The novelty of this approach is that the entire application is browser-based and doesn't require installation of third party plug-ins or additional software components in order to visualize the supported chemical file formats. This kind of solution is suitable for instruction of users in less IT oriented environments, like medicine or chemistry. For rendering various molecular geometries our team used GLmol (a molecular viewer written in JavaScript). The interaction with the 3D models is made with Leap Motion controller that allows real-time tracking of the user's hand gestures. The first results confirmed that the resulting application leads to a better way of understanding various types of translational bioinformatics related problems in both biomedical research and education.

Games Con Men Play: The Semiosis of Deceptive Interaction.

Science.gov (United States)

Hankiss, Agnes

1980-01-01

Analyzes some of the most frequent deceptive interactions as rendered through case histories of male con artists and their victims taken from police records. Discusses the recurrent elements in both the con-games strategies and victims' way of interpreting those strategies. (JMF)

Inadequate increase in the volume of major epicardial coronary arteries compared with that in left ventricular mass. Novel concept for characterization of coronary arteries using 64-slice computed tomography.

Science.gov (United States)

Ehara, Shoichi; Okuyama, Takuhiro; Shirai, Nobuyuki; Sugioka, Kenichi; Oe, Hiroki; Itoh, Toshihide; Matsuoka, Toshiyuki; Ikura, Yoshihiro; Ueda, Makiko; Naruko, Takahiko; Hozumi, Takeshi; Yoshiyama, Minoru

2009-08-01

Previous studies have shown a correlation between coronary artery cross-sectional diameter and left ventricular (LV) mass. However, no studies have examined the correlation between actual coronary artery volume (CAV) and LV mass. In the present study, measurements of CAV by 64-multislice computed tomography (MSCT) were validated and the relationship between CAV and LV mass was investigated. First, coronary artery phantoms consisting of syringes filled with solutions of contrast medium moving at simulated heart rates were scanned by 64-MSCT. Display window settings permitting accurate calculation of small volumes were optimized by evaluating volume-rendered images of the segmented contrast medium at different window settings. Next, 61 patients without significant coronary artery stenosis were scanned by 64-MSCT with the same protocol as for the phantoms. Coronary arteries were segmented on a workstation and the same window settings were applied to the volume-rendered images to calculate total CAV. Significant correlations between total CAV and LV mass (r=0.660, Pconcept of "CAV" for the characterization of coronary arteries may prove useful for future research, particularly on the causes of LV hypertrophy.

Local intelligent electronic device (IED) rendering templates over limited bandwidth communication link to manage remote IED

Science.gov (United States)

Bradetich, Ryan; Dearien, Jason A; Grussling, Barry Jakob; Remaley, Gavin

2013-11-05

The present disclosure provides systems and methods for remote device management. According to various embodiments, a local intelligent electronic device (IED) may be in communication with a remote IED via a limited bandwidth communication link, such as a serial link. The limited bandwidth communication link may not support traditional remote management interfaces. According to one embodiment, a local IED may present an operator with a management interface for a remote IED by rendering locally stored templates. The local IED may render the locally stored templates using sparse data obtained from the remote IED. According to various embodiments, the management interface may be a web client interface and/or an HTML interface. The bandwidth required to present a remote management interface may be significantly reduced by rendering locally stored templates rather than requesting an entire management interface from the remote IED. According to various embodiments, an IED may comprise an encryption transceiver.

New impressive capabilities of SE-workbench for EO/IR real-time rendering of animated scenarios including flares

Science.gov (United States)

Le Goff, Alain; Cathala, Thierry; Latger, Jean

2015-10-01

To provide technical assessments of EO/IR flares and self-protection systems for aircraft, DGA Information superiority resorts to synthetic image generation to model the operational battlefield of an aircraft, as viewed by EO/IR threats. For this purpose, it completed the SE-Workbench suite from OKTAL-SE with functionalities to predict a realistic aircraft IR signature and is yet integrating the real-time EO/IR rendering engine of SE-Workbench called SE-FAST-IR. This engine is a set of physics-based software and libraries that allows preparing and visualizing a 3D scene for the EO/IR domain. It takes advantage of recent advances in GPU computing techniques. The recent past evolutions that have been performed concern mainly the realistic and physical rendering of reflections, the rendering of both radiative and thermal shadows, the use of procedural techniques for the managing and the rendering of very large terrains, the implementation of Image- Based Rendering for dynamic interpolation of plume static signatures and lastly for aircraft the dynamic interpolation of thermal states. The next step is the representation of the spectral, directional, spatial and temporal signature of flares by Lacroix Defense using OKTAL-SE technology. This representation is prepared from experimental data acquired during windblast tests and high speed track tests. It is based on particle system mechanisms to model the different components of a flare. The validation of a flare model will comprise a simulation of real trials and a comparison of simulation outputs to experimental results concerning the flare signature and above all the behavior of the stimulated threat.

Signal Processing Implementation and Comparison of Automotive Spatial Sound Rendering Strategies

Directory of Open Access Journals (Sweden)

Bai MingsianR

2009-01-01

Full Text Available Design and implementation strategies of spatial sound rendering are investigated in this paper for automotive scenarios. Six design methods are implemented for various rendering modes with different number of passengers. Specifically, the downmixing algorithms aimed at balancing the front and back reproductions are developed for the 5.1-channel input. Other five algorithms based on inverse filtering are implemented in two approaches. The first approach utilizes binaural (Head-Related Transfer Functions HRTFs measured in the car interior, whereas the second approach named the point-receiver model targets a point receiver positioned at the center of the passenger's head. The proposed processing algorithms were compared via objective and subjective experiments under various listening conditions. Test data were processed by the multivariate analysis of variance (MANOVA method and the least significant difference (Fisher's LSD method as a post hoc test to justify the statistical significance of the experimental data. The results indicate that inverse filtering algorithms are preferred for the single passenger mode. For the multipassenger mode, however, downmixing algorithms generally outperformed the other processing techniques.

Propulsion and airframe aerodynamic interactions of supersonic V/STOL configurations. Volume 2: Wind tunnel test force and moment data report

Science.gov (United States)

Zilz, D. E.

1985-01-01

A wind tunnel model of a supersonic V/STOL fighter configuration has been tested to measure the aerodynamic interaction effects which can result from geometrically close-coupled propulsion system/airframe components. The approach was to configure the model to represent two different test techniques. One was a conventional test technique composed of two test modes. In the Flow-Through mode, absolute configuration aerodynamics are measured, including inlet/airframe interactions. In the Jet-Effects mode, incremental nozzle/airframe interactions are measured. The other test technique is a propulsion simulator approach, where a sub-scale, externally powered engine is mounted in the model. This allows proper measurement of inlet/airframe and nozzle/airframe interactions simultaneously. This is Volume 2 of 2: Wind Tunnel Test Force and Moment Data Report.

LOD 1 VS. LOD 2 - Preliminary Investigations Into Differences in Mobile Rendering Performance

Science.gov (United States)

Ellul, C.; Altenbuchner, J.

2013-09-01

The increasing availability, size and detail of 3D City Model datasets has led to a challenge when rendering such data on mobile devices. Understanding the limitations to the usability of such models on these devices is particularly important given the broadening range of applications - such as pollution or noise modelling, tourism, planning, solar potential - for which these datasets and resulting visualisations can be utilized. Much 3D City Model data is created by extrusion of 2D topographic datasets, resulting in what is known as Level of Detail (LoD) 1 buildings - with flat roofs. However, in the UK the National Mapping Agency (the Ordnance Survey, OS) is now releasing test datasets to Level of Detail (LoD) 2 - i.e. including roof structures. These datasets are designed to integrate with the LoD 1 datasets provided by the OS, and provide additional detail in particular on larger buildings and in town centres. The availability of such integrated datasets at two different Levels of Detail permits investigation into the impact of the additional roof structures (and hence the display of a more realistic 3D City Model) on rendering performance on a mobile device. This paper describes preliminary work carried out to investigate this issue, for the test area of the city of Sheffield (in the UK Midlands). The data is stored in a 3D spatial database as triangles and then extracted and served as a web-based data stream which is queried by an App developed on the mobile device (using the Android environment, Java and OpenGL for graphics). Initial tests have been carried out on two dataset sizes, for the city centre and a larger area, rendering the data onto a tablet to compare results. Results of 52 seconds for rendering LoD 1 data, and 72 seconds for LoD 1 mixed with LoD 2 data, show that the impact of LoD 2 is significant.

Diagnostic Value of Multidetector CT and Its Multiplanar Reformation, Volume Rendering and Virtual Bronchoscopy Postprocessing Techniques for Primary Trachea and Main Bronchus Tumors.

Directory of Open Access Journals (Sweden)

Mingyue Luo

Full Text Available To evaluate the diagnostic value of multidetector CT (MDCT and its multiplanar reformation (MPR, volume rendering (VR and virtual bronchoscopy (VB postprocessing techniques for primary trachea and main bronchus tumors.Detection results of 31 primary trachea and main bronchus tumors with MDCT and its MPR, VR and VB postprocessing techniques, were analyzed retrospectively with regard to tumor locations, tumor morphologies, extramural invasions of tumors, longitudinal involvements of tumors, morphologies and extents of luminal stenoses, distances between main bronchus tumors and trachea carinae, and internal features of tumors. The detection results were compared with that of surgery and pathology.Detection results with MDCT and its MPR, VR and VB were consistent with that of surgery and pathology, included tumor locations (tracheae, n = 19; right main bronchi, n = 6; left main bronchi, n = 6, tumor morphologies (endoluminal nodes with narrow bases, n = 2; endoluminal nodes with wide bases, n = 13; both intraluminal and extraluminal masses, n = 16, extramural invasions of tumors (brokethrough only serous membrane, n = 1; 4.0 mm-56.0 mm, n = 14; no clear border with right atelectasis, n = 1, longitudinal involvements of tumors (3.0 mm, n = 1; 5.0 mm-68.0 mm, n = 29; whole right main bronchus wall and trachea carina, n = 1, morphologies of luminal stenoses (irregular, n = 26; circular, n = 3; eccentric, n = 1; conical, n = 1 and extents (mild, n = 5; moderate, n = 7; severe, n = 19, distances between main bronchus tumors and trachea carinae (16.0 mm, n = 1; invaded trachea carina, n = 1; >20.0 mm, n = 10, and internal features of tumors (fairly homogeneous densities with rather obvious enhancements, n = 26; homogeneous density with obvious enhancement, n = 1; homogeneous density without obvious enhancement, n = 1; not enough homogeneous density with obvious enhancement, n = 1; punctate calcification with obvious enhancement, n = 1; low density

Diagnostic Value of Multidetector CT and Its Multiplanar Reformation, Volume Rendering and Virtual Bronchoscopy Postprocessing Techniques for Primary Trachea and Main Bronchus Tumors.

Science.gov (United States)

Luo, Mingyue; Duan, Chaijie; Qiu, Jianping; Li, Wenru; Zhu, Dongyun; Cai, Wenli

2015-01-01

To evaluate the diagnostic value of multidetector CT (MDCT) and its multiplanar reformation (MPR), volume rendering (VR) and virtual bronchoscopy (VB) postprocessing techniques for primary trachea and main bronchus tumors. Detection results of 31 primary trachea and main bronchus tumors with MDCT and its MPR, VR and VB postprocessing techniques, were analyzed retrospectively with regard to tumor locations, tumor morphologies, extramural invasions of tumors, longitudinal involvements of tumors, morphologies and extents of luminal stenoses, distances between main bronchus tumors and trachea carinae, and internal features of tumors. The detection results were compared with that of surgery and pathology. Detection results with MDCT and its MPR, VR and VB were consistent with that of surgery and pathology, included tumor locations (tracheae, n = 19; right main bronchi, n = 6; left main bronchi, n = 6), tumor morphologies (endoluminal nodes with narrow bases, n = 2; endoluminal nodes with wide bases, n = 13; both intraluminal and extraluminal masses, n = 16), extramural invasions of tumors (brokethrough only serous membrane, n = 1; 4.0 mm-56.0 mm, n = 14; no clear border with right atelectasis, n = 1), longitudinal involvements of tumors (3.0 mm, n = 1; 5.0 mm-68.0 mm, n = 29; whole right main bronchus wall and trachea carina, n = 1), morphologies of luminal stenoses (irregular, n = 26; circular, n = 3; eccentric, n = 1; conical, n = 1) and extents (mild, n = 5; moderate, n = 7; severe, n = 19), distances between main bronchus tumors and trachea carinae (16.0 mm, n = 1; invaded trachea carina, n = 1; >20.0 mm, n = 10), and internal features of tumors (fairly homogeneous densities with rather obvious enhancements, n = 26; homogeneous density with obvious enhancement, n = 1; homogeneous density without obvious enhancement, n = 1; not enough homogeneous density with obvious enhancement, n = 1; punctate calcification with obvious enhancement, n = 1; low density without

Detailed requirements document for the Interactive Financial Management System (IFMS), volume 1

Science.gov (United States)

Dodson, D. B.

1975-01-01

The detailed requirements for phase 1 (online fund control, subauthorization accounting, and accounts receivable functional capabilities) of the Interactive Financial Management System (IFMS) are described. This includes information on the following: systems requirements, performance requirements, test requirements, and production implementation. Most of the work is centered on systems requirements, and includes discussions on the following processes: resources authority, allotment, primary work authorization, reimbursable order acceptance, purchase request, obligation, cost accrual, cost distribution, disbursement, subauthorization performance, travel, accounts receivable, payroll, property, edit table maintenance, end-of-year, backup input. Other subjects covered include: external systems interfaces, general inquiries, general report requirements, communication requirements, and miscellaneous. Subjects covered under performance requirements include: response time, processing volumes, system reliability, and accuracy. Under test requirements come test data sources, general test approach, and acceptance criteria. Under production implementation come data base establishment, operational stages, and operational requirements.

A Finite-Volume approach for compressible single- and two-phase flows in flexible pipelines with fluid-structure interaction

Science.gov (United States)

Daude, F.; Galon, P.

2018-06-01

A Finite-Volume scheme for the numerical computations of compressible single- and two-phase flows in flexible pipelines is proposed based on an approximate Godunov-type approach. The spatial discretization is here obtained using the HLLC scheme. In addition, the numerical treatment of abrupt changes in area and network including several pipelines connected at junctions is also considered. The proposed approach is based on the integral form of the governing equations making it possible to tackle general equations of state. A coupled approach for the resolution of fluid-structure interaction of compressible fluid flowing in flexible pipes is considered. The structural problem is solved using Euler-Bernoulli beam finite elements. The present Finite-Volume method is applied to ideal gas and two-phase steam-water based on the Homogeneous Equilibrium Model (HEM) in conjunction with a tabulated equation of state in order to demonstrate its ability to tackle general equations of state. The extensive application of the scheme for both shock tube and other transient flow problems demonstrates its capability to resolve such problems accurately and robustly. Finally, the proposed 1-D fluid-structure interaction model appears to be computationally efficient.

Moisture transport properties of brick – comparison of exposed, impregnated and rendered brick

DEFF Research Database (Denmark)

Hansen, Tessa Kvist; Bjarløv, Søren Peter; Peuhkuri, Ruut

2016-01-01

In regards to internal insulation of preservation worthy brick façades, external moisture sources, such as wind-driven rain exposure, inevitably has an impact on moisture conditions within the masonry construction. Surface treatments, such as hydrophobation or render, may remedy the impacts...... of external moisture. In the present paper the surface absorption of liquid water on masonry façades of untreated, hydrophobated and rendered brick, are determined experimentally and compared. The experimental work focuses on methods that can be applied on-site, Karsten tube measurements. These measurements...... are supplemented with results from laboratory measurements of water absorption coefficient by partial immersion. Based on obtained measurement results, simulations are made with external liquid water loads for determination of moisture conditions within the masonry of different surface treatments. Experimental...

Interaction between peri-operative blood transfusion, tidal volume, airway pressure and postoperative ARDS: an individual patient data meta-analysis.

Science.gov (United States)

Serpa Neto, Ary; Juffermans, Nicole P; Hemmes, Sabrine N T; Barbas, Carmen S V; Beiderlinden, Martin; Biehl, Michelle; Fernandez-Bustamante, Ana; Futier, Emmanuel; Gajic, Ognjen; Jaber, Samir; Kozian, Alf; Licker, Marc; Lin, Wen-Qian; Memtsoudis, Stavros G; Miranda, Dinis Reis; Moine, Pierre; Paparella, Domenico; Ranieri, Marco; Scavonetto, Federica; Schilling, Thomas; Selmo, Gabriele; Severgnini, Paolo; Sprung, Juraj; Sundar, Sugantha; Talmor, Daniel; Treschan, Tanja; Unzueta, Carmen; Weingarten, Toby N; Wolthuis, Esther K; Wrigge, Hermann; de Abreu, Marcelo Gama; Pelosi, Paolo; Schultz, Marcus J

2018-01-01

Transfusion of blood products and mechanical ventilation with injurious settings are considered risk factors for postoperative lung injury in surgical Patients. A systematic review and individual patient data meta-analysis was done to determine the independent effects of peri-operative transfusion of blood products, intra-operative tidal volume and airway pressure in adult patients undergoing mechanical ventilation for general surgery, as well as their interactions on the occurrence of postoperative acute respiratory distress syndrome (ARDS). Observational studies and randomized trials were identified by a systematic search of MEDLINE, CINAHL, Web of Science, and CENTRAL and screened for inclusion into a meta-analysis. Individual patient data were obtained from the corresponding authors. Patients were stratified according to whether they received transfusion in the peri-operative period [red blood cell concentrates (RBC) and/or fresh frozen plasma (FFP)], tidal volume size [≤7 mL/kg predicted body weight (PBW), 7-10 and >10 mL/kg PBW] and airway pressure level used during surgery (≤15, 15-20 and >20 cmH 2 O). The primary outcome was development of postoperative ARDS. Seventeen investigations were included (3,659 patients). Postoperative ARDS occurred in 40 (7.2%) patients who received at least one blood product compared to 40 patients (2.5%) who did not [adjusted hazard ratio (HR), 2.32; 95% confidence interval (CI), 1.25-4.33; P=0.008]. Incidence of postoperative ARDS was highest in patients ventilated with tidal volumes of >10 mL/kg PBW and having airway pressures of >20 cmH 2 O receiving both RBC and FFP, and lowest in patients ventilated with tidal volume of ≤7 mL/kg PBW and having airway pressures of ≤15 cmH 2 O with no transfusion. There was a significant interaction between transfusion and airway pressure level (P=0.002) on the risk of postoperative ARDS. Peri-operative transfusion of blood products is associated with an increased risk of

An Innovative Direct-Interaction-Enabled Augmented-Reality 3D System

Directory of Open Access Journals (Sweden)

Sheng-Hsiung Chang

2013-01-01

Full Text Available Previous augmented-reality (AR applications have required users to observe the integration of real and virtual images on a display. This study proposes a novel concept regarding AR applications. By integrating AR techniques with marker identification, virtual-image output, imaging, and image-interaction processes, this study rendered virtual images that can interact with predefined markers in a real three-dimensional (3D environment.

Apparatus for rendering at least a portion of a device inoperable and related methods

Energy Technology Data Exchange (ETDEWEB)

Daniels, Michael A.; Steffler, Eric D.; Hartenstein, Steven D.; Wallace, Ronald S.

2016-11-08

Apparatus for rendering at least a portion of a device inoperable may include a containment structure having a first compartment that is configured to receive a device therein and a movable member configured to receive a cartridge having reactant material therein. The movable member is configured to be inserted into the first compartment of the containment structure and to ignite the reactant material within the cartridge. Methods of rendering at least a portion of a device inoperable may include disposing the device into the first compartment of the containment structure, inserting the movable member into the first compartment of the containment structure, igniting the reactant material in the cartridge, and expelling molten metal onto the device.

iview: an interactive WebGL visualizer for protein-ligand complex.

Science.gov (United States)

Li, Hongjian; Leung, Kwong-Sak; Nakane, Takanori; Wong, Man-Hon

2014-02-25

Visualization of protein-ligand complex plays an important role in elaborating protein-ligand interactions and aiding novel drug design. Most existing web visualizers either rely on slow software rendering, or lack virtual reality support. The vital feature of macromolecular surface construction is also unavailable. We have developed iview, an easy-to-use interactive WebGL visualizer of protein-ligand complex. It exploits hardware acceleration rather than software rendering. It features three special effects in virtual reality settings, namely anaglyph, parallax barrier and oculus rift, resulting in visually appealing identification of intermolecular interactions. It supports four surface representations including Van der Waals surface, solvent excluded surface, solvent accessible surface and molecular surface. Moreover, based on the feature-rich version of iview, we have also developed a neat and tailor-made version specifically for our istar web platform for protein-ligand docking purpose. This demonstrates the excellent portability of iview. Using innovative 3D techniques, we provide a user friendly visualizer that is not intended to compete with professional visualizers, but to enable easy accessibility and platform independence.

Efficient Algorithms for Real-Time GPU Volumetric Cloud Rendering with Enhanced Geometry

Directory of Open Access Journals (Sweden)

Carlos Jiménez de Parga

2018-04-01

Full Text Available This paper presents several new techniques for volumetric cloud rendering using efficient algorithms and data structures based on ray-tracing methods for cumulus generation, achieving an optimum balance between realism and performance. These techniques target applications such as flight simulations, computer games, and educational software, even with conventional graphics hardware. The contours of clouds are defined by implicit mathematical expressions or triangulated structures inside which volumetric rendering is performed. Novel techniques are used to reproduce the asymmetrical nature of clouds and the effects of light-scattering, with low computing costs. The work includes a new method to create randomized fractal clouds using a recursive grammar. The graphical results are comparable to those produced by state-of-the-art, hyper-realistic algorithms. These methods provide real-time performance, and are superior to particle-based systems. These outcomes suggest that our methods offer a good balance between realism and performance, and are suitable for use in the standard graphics industry.

Interactive design center.

Energy Technology Data Exchange (ETDEWEB)

Pomplun, Alan R. (Sandia National Laboratories, Livermore, CA)

2005-07-01

Sandia's advanced computing resources provide researchers, engineers and analysts with the ability to develop and render highly detailed large-scale models and simulations. To take full advantage of these multi-million data point visualizations, display systems with comparable pixel counts are needed. The Interactive Design Center (IDC) is a second generation visualization theater designed to meet this need. The main display integrates twenty-seven projectors in a 9-wide by 3-high array with a total display resolution of more than 35 million pixels. Six individual SmartBoard displays offer interactive capabilities that include on-screen annotation and touch panel control of the facility's display systems. This report details the design, implementation and operation of this innovative facility.

Seeing More by Showing Less: Orientation-Dependent Transparency Rendering for Fiber Tractography Visualization.

Directory of Open Access Journals (Sweden)

Chantal M W Tax

Full Text Available Fiber tractography plays an important role in exploring the architectural organization of fiber trajectories, both in fundamental neuroscience and in clinical applications. With the advent of diffusion MRI (dMRI approaches that can also model "crossing fibers", the complexity of the fiber network as reconstructed with tractography has increased tremendously. Many pathways interdigitate and overlap, which hampers an unequivocal 3D visualization of the network and impedes an efficient study of its organization. We propose a novel fiber tractography visualization approach that interactively and selectively adapts the transparency rendering of fiber trajectories as a function of their orientation to enhance the visibility of the spatial context. More specifically, pathways that are oriented (locally or globally along a user-specified opacity axis can be made more transparent or opaque. This substantially improves the 3D visualization of the fiber network and the exploration of tissue configurations that would otherwise be largely covered by other pathways. We present examples of fiber bundle extraction and neurosurgical planning cases where the added benefit of our new visualization scheme is demonstrated over conventional fiber visualization approaches.

Three-body unitarity in the finite volume

Energy Technology Data Exchange (ETDEWEB)

Mai, M. [The George Washington University, Washington, DC (United States); Doering, M. [The George Washington University, Washington, DC (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2017-12-15

The physical interpretation of lattice QCD simulations, performed in a small volume, requires an extrapolation to the infinite volume. A method is proposed to perform such an extrapolation for three interacting particles at energies above threshold. For this, a recently formulated relativistic 3 → 3 amplitude based on the isobar formulation is adapted to the finite volume. The guiding principle is two- and three-body unitarity that imposes the imaginary parts of the amplitude in the infinite volume. In turn, these imaginary parts dictate the leading power-law finite-volume effects. It is demonstrated that finite-volume poles arising from the singular interaction, from the external two-body sub-amplitudes, and from the disconnected topology cancel exactly leaving only the genuine three-body eigenvalues. The corresponding quantization condition is derived for the case of three identical scalar-isoscalar particles and its numerical implementation is demonstrated. (orig.)

Modeling a color-rendering operator for high dynamic range images using a cone-response function

Science.gov (United States)

Choi, Ho-Hyoung; Kim, Gi-Seok; Yun, Byoung-Ju

2015-09-01

Tone-mapping operators are the typical algorithms designed to produce visibility and the overall impression of brightness, contrast, and color of high dynamic range (HDR) images on low dynamic range (LDR) display devices. Although several new tone-mapping operators have been proposed in recent years, the results of these operators have not matched those of the psychophysical experiments based on the human visual system. A color-rendering model that is a combination of tone-mapping and cone-response functions using an XYZ tristimulus color space is presented. In the proposed method, the tone-mapping operator produces visibility and the overall impression of brightness, contrast, and color in HDR images when mapped onto relatively LDR devices. The tone-mapping resultant image is obtained using chromatic and achromatic colors to avoid well-known color distortions shown in the conventional methods. The resulting image is then processed with a cone-response function wherein emphasis is placed on human visual perception (HVP). The proposed method covers the mismatch between the actual scene and the rendered image based on HVP. The experimental results show that the proposed method yields an improved color-rendering performance compared to conventional methods.

The interactive effects of temperature and moisture on nitrogen fixation in two temperate-arctic mosses

DEFF Research Database (Denmark)

Rousk, Kathrin; Pedersen, Pia Agerlund; Dyrnum, Kristine

2017-01-01

fixation in mosses under controlled conditions have rarely been investigated separately, rendering the interactive effects of the two climatic factors on N2 fixation unknown. Here, we tested the interactive effects of temperature and moisture on N2 fixation in the two most dominant moss species...

Interactive 3D visualization for theoretical virtual observatories

Science.gov (United States)

Dykes, T.; Hassan, A.; Gheller, C.; Croton, D.; Krokos, M.

2018-06-01

Virtual observatories (VOs) are online hubs of scientific knowledge. They encompass a collection of platforms dedicated to the storage and dissemination of astronomical data, from simple data archives to e-research platforms offering advanced tools for data exploration and analysis. Whilst the more mature platforms within VOs primarily serve the observational community, there are also services fulfilling a similar role for theoretical data. Scientific visualization can be an effective tool for analysis and exploration of data sets made accessible through web platforms for theoretical data, which often contain spatial dimensions and properties inherently suitable for visualization via e.g. mock imaging in 2D or volume rendering in 3D. We analyse the current state of 3D visualization for big theoretical astronomical data sets through scientific web portals and virtual observatory services. We discuss some of the challenges for interactive 3D visualization and how it can augment the workflow of users in a virtual observatory context. Finally we showcase a lightweight client-server visualization tool for particle-based data sets, allowing quantitative visualization via data filtering, highlighting two example use cases within the Theoretical Astrophysical Observatory.

Interactive 3D Visualization for Theoretical Virtual Observatories

Science.gov (United States)

Dykes, Tim; Hassan, A.; Gheller, C.; Croton, D.; Krokos, M.

2018-04-01

Virtual Observatories (VOs) are online hubs of scientific knowledge. They encompass a collection of platforms dedicated to the storage and dissemination of astronomical data, from simple data archives to e-research platforms offering advanced tools for data exploration and analysis. Whilst the more mature platforms within VOs primarily serve the observational community, there are also services fulfilling a similar role for theoretical data. Scientific visualization can be an effective tool for analysis and exploration of datasets made accessible through web platforms for theoretical data, which often contain spatial dimensions and properties inherently suitable for visualization via e.g. mock imaging in 2d or volume rendering in 3d. We analyze the current state of 3d visualization for big theoretical astronomical datasets through scientific web portals and virtual observatory services. We discuss some of the challenges for interactive 3d visualization and how it can augment the workflow of users in a virtual observatory context. Finally we showcase a lightweight client-server visualization tool for particle-based datasets allowing quantitative visualization via data filtering, highlighting two example use cases within the Theoretical Astrophysical Observatory.

Optimization Model for Web Based Multimodal Interactive Simulations.

Science.gov (United States)

Halic, Tansel; Ahn, Woojin; De, Suvranu

2015-07-15

This paper presents a technique for optimizing the performance of web based multimodal interactive simulations. For such applications where visual quality and the performance of simulations directly influence user experience, overloading of hardware resources may result in unsatisfactory reduction in the quality of the simulation and user satisfaction. However, optimization of simulation performance on individual hardware platforms is not practical. Hence, we present a mixed integer programming model to optimize the performance of graphical rendering and simulation performance while satisfying application specific constraints. Our approach includes three distinct phases: identification, optimization and update . In the identification phase, the computing and rendering capabilities of the client device are evaluated using an exploratory proxy code. This data is utilized in conjunction with user specified design requirements in the optimization phase to ensure best possible computational resource allocation. The optimum solution is used for rendering (e.g. texture size, canvas resolution) and simulation parameters (e.g. simulation domain) in the update phase. Test results are presented on multiple hardware platforms with diverse computing and graphics capabilities to demonstrate the effectiveness of our approach.

On-the-Fly Decompression and Rendering of Multiresolution Terrain

Energy Technology Data Exchange (ETDEWEB)

Lindstrom, P; Cohen, J D

2009-04-02

We present a streaming geometry compression codec for multiresolution, uniformly-gridded, triangular terrain patches that supports very fast decompression. Our method is based on linear prediction and residual coding for lossless compression of the full-resolution data. As simplified patches on coarser levels in the hierarchy already incur some data loss, we optionally allow further quantization for more lossy compression. The quantization levels are adaptive on a per-patch basis, while still permitting seamless, adaptive tessellations of the terrain. Our geometry compression on such a hierarchy achieves compression ratios of 3:1 to 12:1. Our scheme is not only suitable for fast decompression on the CPU, but also for parallel decoding on the GPU with peak throughput over 2 billion triangles per second. Each terrain patch is independently decompressed on the fly from a variable-rate bitstream by a GPU geometry program with no branches or conditionals. Thus we can store the geometry compressed on the GPU, reducing storage and bandwidth requirements throughout the system. In our rendering approach, only compressed bitstreams and the decoded height values in the view-dependent 'cut' are explicitly stored on the GPU. Normal vectors are computed in a streaming fashion, and remaining geometry and texture coordinates, as well as mesh connectivity, are shared and re-used for all patches. We demonstrate and evaluate our algorithms on a small prototype system in which all compressed geometry fits in the GPU memory and decompression occurs on the fly every rendering frame without any cache maintenance.

Final Environmental Impact Statement for Development of Facilities to Support Basing US Pacific Fleet F/A-18E/F Aircraft on the West Coast of the United States, Volume 1.

Science.gov (United States)

1998-05-01

California, pp. 592-609. Robert F. Heizer , Volume Editor. William C. Sturtevant, General Editor. Smithsonian Institution, Washington, DC. Machado, Dee...American Indians, Vol. 8. California, pp. 448-461. Robert F. Heizer , Volume Editor. William C. Sturtevant, General Editor. Smithsonian Institution... rendered in quintuplicate to: Commanding Officer " Naval Air Station =Lemoore, California ^l" Payments will be^made by: Commanding Officer Navy

Uniform illumination rendering using an array of LEDs: a signal processing perspective

NARCIS (Netherlands)

Yang, Hongming; Bergmans, J.W.M.; Schenk, T.C.W.; Linnartz, J.P.M.G.; Rietman, R.

2009-01-01

An array of a large number of LEDs will be widely used in future indoor illumination systems. In this paper, we investigate the problem of rendering uniform illumination by a regular LED array on the ceiling of a room. We first present two general results on the scaling property of the basic

An economic analysis of localized pollution: rendering emissions in a residential setting

Science.gov (United States)

J. Michael Bowker; H.F. MacDonald

1991-01-01

The contingent value method is employed to estimate economic damages to households resulting from rendering plant emissions in a small town. Household willingness to accept (WTA) and willingness to pay (WTP) are estimated individually and in aggregate. The influence of household characteristics on WTP and WTA is examined via regression models. The perception of health...

Mesophilic and thermophilic anaerobic co-digestion of rendering plant and slaughterhouse wastes.

Science.gov (United States)

Bayr, Suvi; Rantanen, Marianne; Kaparaju, Prasad; Rintala, Jukka

2012-01-01

Co-digestion of rendering and slaughterhouse wastes was studied in laboratory scale semi-continuously fed continuously stirred tank reactors (CSTRs) at 35 and 55 °C. All in all, 10 different rendering plant and slaughterhouse waste fractions were characterised showing high contents of lipids and proteins, and methane potentials of 262-572 dm(3)CH(4)/kg volatile solids(VS)(added). In mesophilic CSTR methane yields of ca 720 dm(3) CH(4)/kg VS(fed) were obtained with organic loading rates (OLR) of 1.0 and 1.5 kg VS/m(3) d, and hydraulic retention time (HRT) of 50 d. For thermophilic process, the lowest studied OLR of 1.5 kg VS/m(3) d, turned to be unstable after operation of 1.5 HRT, due to accumulating ammonia, volatile fatty acids (VFAs) and probably also long chain fatty acids (LCFAs). In conclusion, mesophilic process was found to be more feasible for co-digestion than thermophilic process, methane yields being higher and process more stable in mesophilic conditions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Investigation of nanoscopic free volume and interfacial interaction in an epoxy resin/modified clay nanocomposite using positron annihilation spectroscopy.

Science.gov (United States)

Patil, Pushkar N; Sudarshan, Kathi; Sharma, Sandeep K; Maheshwari, Priya; Rath, Sangram K; Patri, Manoranjan; Pujari, Pradeep K

2012-12-07

Epoxy/clay nanocomposites are synthesized using clay modified with the organic modifier N,N-dimethyl benzyl hydrogenated tallow quaternary ammonium salt (Cloisite 10A). The purpose is to investigate the influence of the clay concentration on the nanostructure, mainly on the free-volume properties and the interfacial interactions, of the epoxy/clay nanocomposite. Nanocomposites having 1, 3, 5 and 7.5 wt. % clay concentrations are prepared using the solvent-casting method. The dispersion of clay silicate layers and the morphologies of the fractured surfaces in the nanocomposites are studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The observed XRD patterns reveal an exfoliated clay structure in the nanocomposite with the lowest clay concentration (≤1 wt. %). The ortho-positronium lifetime (τ(3)), a measure of the free-volume size, as well as the fractional free volume (f(v)) are seen to decrease in the nanocomposites as compared to pristine epoxy. The intensity of free positron annihilation (I(2)), an index of the epoxy-clay interaction, decreases with the addition of clay (1 wt. %) but increases linearly at higher clay concentrations. Positron age-momentum correlation measurements are also carried out to elucidate the positron/positronium states in pristine epoxy and in the nanocomposites. The results suggest that in the case of the nanocomposite with the studied lowest clay concentration (1 wt. %), free positrons are primarily localized in the epoxy-clay interfaces, whereas at higher clay concentrations, annihilation takes place from the intercalated clay layers. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rendering Large-Scale Terrain Models and Positioning Objects in Relation to 3D Terrain

National Research Council Canada - National Science Library

Hittner, Brian

2003-01-01

.... Rendering large scale landscapes based on 3D geometry generally did not occur because the scenes generated tended to use up too much system memory and overburden 3D graphics cards with too many polygons...

Short interactive workshops reduce variability in contouring treatment volumes for spine stereotactic body radiation therapy: Experience with the ESTRO FALCON programme and EduCase™ training tool.

Science.gov (United States)

De Bari, Berardino; Dahele, Max; Palmu, Miika; Kaylor, Scott; Schiappacasse, Luis; Guckenberger, Matthias

2017-11-20

We report the results of 4, 2-h contouring workshops on target volume definition for spinal stereotactic radiotherapy. They combined traditional teaching methods with a web-based contouring/contour-analysis platform and led to a significant reduction in delineation variability. Short, interactive workshops can reduce interobserver variability in spine SBRT target volume delineation. Copyright © 2017 Elsevier B.V. All rights reserved.

Skype me! Socially Contingent Interactions Help Toddlers Learn Language

Science.gov (United States)

Roseberry, Sarah; Hirsh-Pasek, Kathy; Golinkoff, Roberta Michnick

2013-01-01

Language learning takes place in the context of social interactions, yet the mechanisms that render social interactions useful for learning language remain unclear. This paper focuses on whether social contingency might support word learning. Toddlers aged 24- to 30-months (N=36) were exposed to novel verbs in one of three conditions: live interaction training, socially contingent video training over video chat, and non-contingent video training (yoked video). Results suggest that children only learned novel verbs in socially contingent interactions (live interactions and video chat). The current study highlights the importance of social contingency in interactions for language learning and informs the literature on learning through screen media as the first study to examine word learning through video chat technology. PMID:24112079

3D-TV System with Depth-Image-Based Rendering Architectures, Techniques and Challenges

CERN Document Server

Zhao, Yin; Yu, Lu; Tanimoto, Masayuki

2013-01-01

Riding on the success of 3D cinema blockbusters and advances in stereoscopic display technology, 3D video applications have gathered momentum in recent years. 3D-TV System with Depth-Image-Based Rendering: Architectures, Techniques and Challenges surveys depth-image-based 3D-TV systems, which are expected to be put into applications in the near future. Depth-image-based rendering (DIBR) significantly enhances the 3D visual experience compared to stereoscopic systems currently in use. DIBR techniques make it possible to generate additional viewpoints using 3D warping techniques to adjust the perceived depth of stereoscopic videos and provide for auto-stereoscopic displays that do not require glasses for viewing the 3D image.   The material includes a technical review and literature survey of components and complete systems, solutions for technical issues, and implementation of prototypes. The book is organized into four sections: System Overview, Content Generation, Data Compression and Transmission, and 3D V...

A Practical Framework for Sharing and Rendering Real-World Bidirectional Scattering Distribution Functions

Energy Technology Data Exchange (ETDEWEB)

Ward, Greg [Anywhere Software, Albany, CA (United States); Kurt, Murat [International Computer Institute, Ege University (Turkey); Bonneel, Nicolas [Harvard Univ., Cambridge, MA (United States)

2012-09-30

The utilization of real-world materials has been hindered by a lack of standards for sharing and interpreting measured data. This paper presents an XML representation and an Open Source C library to support bidirectional scattering distribution functions (BSDFs) in data-driven lighting simulation and rendering applications.The library provides for the efficient representation, query, and Monte Carlo sampling of arbitrary BSDFs in amodel-free framework. Currently, we support two BSDF data representations: one using a fixed subdivision of thehemisphere, and one with adaptive density. The fixed type has advantages for certain matrix operations, while theadaptive type can more accurately represent highly peaked data. We discuss advanced methods for data-drivenBSDF rendering for both types, including the proxy of detailed geometry to enhance appearance and accuracy.We also present an advanced interpolation method to reduce measured data into these standard representations.We end with our plan for future extensions and sharing of BSDF data.

The SEMA5A gene is associated with hippocampal volume, and their interaction is associated with performance on Raven's Progressive Matrices.

Science.gov (United States)

Zhu, Bi; Chen, Chuansheng; Xue, Gui; Moyzis, Robert K; Dong, Qi; Chen, Chunhui; Li, Jin; He, Qinghua; Lei, Xuemei; Wang, Yunxin; Lin, Chongde

2014-03-01

The Allen Brain Atlas shows that the semaphorin 5A (SEMA5A) gene, which encodes an important protein for neurogenesis and neuronal apoptosis, is predominantly expressed in the human hippocampus. Structural and functional neuroimaging studies have further shown that the hippocampus plays an important role in the performance on Raven's Progressive Matrices (RPM), a measure of reasoning ability and general fluid intelligence. Thus far, however, no study has examined the relationships between the SEMA5A gene polymorphism, hippocampal volume, and RPM performance. The current study collected both structural MRI, genetic, and behavioral data in 329 healthy Chinese adults, and examined associations between SEMA5A variants, hippocampal volume, and performance on RAPM (the advanced form of RPM). After controlling for intracranial volume (ICV), sex, and age, SEMA5A genetic polymorphism at the SNP rs42352 had the strongest association with hippocampal volume (p=0.00000552 and 0.000103 for right and left hippocampal volumes, respectively), with TT homozygotes having higher hippocampal volume than the other genotypes. Furthermore, there was a high correlation between right hippocampal volume and RAPM performance (r=0.42, p=0.0000509) for SEMA5A rs42352 TT homozygotes. This study provides the first evidence for the involvement of the SEMA5A gene in hippocampal structure and their interaction on RAPM performance. Future studies of the hippocampus-RPM associations should consider genetic factors as potential moderators. Copyright © 2013 Elsevier Inc. All rights reserved.

Visapult: A Prototype Remote and Distributed Visualization Application and Framework

International Nuclear Information System (INIS)

Bethel, Wes

2000-01-01

We describe an approach used for implementing a highly efficient and scalable method for direct volume rendering. Our approach uses a pipelined-parallel decomposition composed of parallel computers and commodity desktop hardware. With our approach, desktop interactivity is divorced from the latency inherent in network-based applications

Heterogeneous Deformable Modeling of Bio-Tissues and Haptic Force Rendering for Bio-Object Modeling

Science.gov (United States)

Lin, Shiyong; Lee, Yuan-Shin; Narayan, Roger J.

This paper presents a novel technique for modeling soft biological tissues as well as the development of an innovative interface for bio-manufacturing and medical applications. Heterogeneous deformable models may be used to represent the actual internal structures of deformable biological objects, which possess multiple components and nonuniform material properties. Both heterogeneous deformable object modeling and accurate haptic rendering can greatly enhance the realism and fidelity of virtual reality environments. In this paper, a tri-ray node snapping algorithm is proposed to generate a volumetric heterogeneous deformable model from a set of object interface surfaces between different materials. A constrained local static integration method is presented for simulating deformation and accurate force feedback based on the material properties of a heterogeneous structure. Biological soft tissue modeling is used as an example to demonstrate the proposed techniques. By integrating the heterogeneous deformable model into a virtual environment, users can both observe different materials inside a deformable object as well as interact with it by touching the deformable object using a haptic device. The presented techniques can be used for surgical simulation, bio-product design, bio-manufacturing, and medical applications.

Binaural Rendering in MPEG Surround

Directory of Open Access Journals (Sweden)

Kristofer Kjörling

2008-04-01

Full Text Available This paper describes novel methods for evoking a multichannel audio experience over stereo headphones. In contrast to the conventional convolution-based approach where, for example, five input channels are filtered using ten head-related transfer functions, the current approach is based on a parametric representation of the multichannel signal, along with either a parametric representation of the head-related transfer functions or a reduced set of head-related transfer functions. An audio scene with multiple virtual sound sources is represented by a mono or a stereo downmix signal of all sound source signals, accompanied by certain statistical (spatial properties. These statistical properties of the sound sources are either combined with statistical properties of head-related transfer functions to estimate “binaural parameters” that represent the perceptually relevant aspects of the auditory scene or used to create a limited set of combined head-related transfer functions that can be applied directly on the downmix signal. Subsequently, a binaural rendering stage reinstates the statistical properties of the sound sources by applying the estimated binaural parameters or the reduced set of combined head-related transfer functions directly on the downmix. If combined with parametric multichannel audio coders such as MPEG Surround, the proposed methods are advantageous over conventional methods in terms of perceived quality and computational complexity.

Interactive methods for exploring particle simulation data

Energy Technology Data Exchange (ETDEWEB)

Co, Christopher S.; Friedman, Alex; Grote, David P.; Vay, Jean-Luc; Bethel, E. Wes; Joy, Kenneth I.

2004-05-01

In this work, we visualize high-dimensional particle simulation data using a suite of scatter plot-based visualizations coupled with interactive selection tools. We use traditional 2D and 3D projection scatter plots as well as a novel oriented disk rendering style to convey various information about the data. Interactive selection tools allow physicists to manually classify ''interesting'' sets of particles that are highlighted across multiple, linked views of the data. The power of our application is the ability to correspond new visual representations of the simulation data with traditional, well understood visualizations. This approach supports the interactive exploration of the high-dimensional space while promoting discovery of new particle behavior.

Major Deficiencies Preventing Auditors From Rendering Audit Opinions on DOD General Fund Financial Statements

National Research Council Canada - National Science Library

Rauu, Russell

1995-01-01

.... We plan to issue a similar report each year. The audit objective was to identify and summarize the major deficiencies that prevented auditors from rendering audit opinions, other than disclaimers, on Army and Air Force general fund financial...

Sigmoid Colon Elongation Evaluation by Volume Rendering Technique

Directory of Open Access Journals (Sweden)

Atilla SENAYLI

2011-06-01

Full Text Available Sigmoid colons have various measurements, shapes, and configurations for individuals. In this subject there are rare clinical trials to answer the question of sigmoidal colon maldevelopment predicting a risk for volvulus. Therefore, sigmoid colon measurement may be beneficial to decide for volvulus. In a study, sigmoid colon diameters were evaluated during abdominal surgeries and it was found that median length was 47 cm and median vertical mesocolon length was 13 cm. We report a 14-year-old female patient who has a sigmoidal colon measured as nearly 54 cm. We used tomographic equipments for this evaluation. We know that MRI technique was used for this purpose but, there has not been data for MRI predicting the sigmoidal volvulus. We hope that our findings by this evaluation can contribute to insufficient literature of sigmoidal elongation. [J Contemp Med 2011; 1(2.000: 71-73

Pyrite: A blender plugin for visualizing molecular dynamics simulations using industry-standard rendering techniques.

Science.gov (United States)

Rajendiran, Nivedita; Durrant, Jacob D

2018-05-05

Molecular dynamics (MD) simulations provide critical insights into many biological mechanisms. Programs such as VMD, Chimera, and PyMOL can produce impressive simulation visualizations, but they lack many advanced rendering algorithms common in the film and video-game industries. In contrast, the modeling program Blender includes such algorithms but cannot import MD-simulation data. MD trajectories often require many gigabytes of memory/disk space, complicating Blender import. We present Pyrite, a Blender plugin that overcomes these limitations. Pyrite allows researchers to visualize MD simulations within Blender, with full access to Blender's cutting-edge rendering techniques. We expect Pyrite-generated images to appeal to students and non-specialists alike. A copy of the plugin is available at http://durrantlab.com/pyrite/, released under the terms of the GNU General Public License Version 3. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Cloud-based Monte Carlo modelling of BSSRDF for the rendering of human skin appearance (Conference Presentation)

Science.gov (United States)

Doronin, Alexander; Rushmeier, Holly E.; Meglinski, Igor; Bykov, Alexander V.

2016-03-01

We present a new Monte Carlo based approach for the modelling of Bidirectional Scattering-Surface Reflectance Distribution Function (BSSRDF) for accurate rendering of human skin appearance. The variations of both skin tissues structure and the major chromophores are taken into account correspondingly to the different ethnic and age groups. The computational solution utilizes HTML5, accelerated by the graphics processing units (GPUs), and therefore is convenient for the practical use at the most of modern computer-based devices and operating systems. The results of imitation of human skin reflectance spectra, corresponding skin colours and examples of 3D faces rendering are presented and compared with the results of phantom studies.

Partitioning of biocides between water and inorganic phases of render

DEFF Research Database (Denmark)

Urbanczyk, Michal; Bollmann, Ulla E.; Bester, Kai

The use of biocides as additives for building materials has gained importance in recent years. These biocides are, e.g., applied to renders and paints to prevent them from microbial spoilage. However, these biocides can leach out into the environment. In order to better understand this leaching...... compared. The partitioning constants for calcium carbonate varied between 0.1 (isoproturon) and 1.1 (iodocarb) and 84.6 (dichlorooctylisothiazolinone), respectively. The results for barite, kaolinite and mica were in a similar range and usually the compounds with high partitioning constants for one mineral...

Cortisol, Cytokines, and Hippocampal Volume in the Elderly

Directory of Open Access Journals (Sweden)

Keith Daniel Sudheimer

2014-07-01

Full Text Available Separate bodies of literature report that elevated pro-inflammatory cytokines and cortisol negatively affect hippocampal structure and cognitive functioning, particularly in older adults. Although interactions between cytokines and cortisol occur through a variety of known mechanisms, few studies consider how their interactions affect brain structure. In this preliminary study, we assess the impact of interactions between circulating levels of IL-1Beta, IL-6, IL-8, IL-10, IL-12, TNF-alpha, and waking cortisol on hippocampal volume. Twenty-eight community-dwelling older adults underwent blood draws for quantification of circulating cytokines and saliva collections to quantify the cortisol awakening response. Hippocampal volume measurements were made using structural magnetic resonance imaging. Elevated levels of waking cortisol in conjunction with higher concentrations of IL-6 and TNF-alpha were associated with smaller hippocampal volumes. In addition, independent of cortisol, higher levels of IL-1beta and TNF-alpha were also associated with smaller hippocampal volumes. These data provide preliminary evidence that higher cortisol, in conjunction with higher IL-6 and TNF-alpha, are associated with smaller hippocampal volume in older adults. We suggest that the dynamic balance between the hypothalamic-pituitary adrenal axis and inflammation processes may explain hippocampal volume reductions in older adults better than either set of measures do in isolation.

Simple Coatings to Render Polystyrene Protein Resistant

Directory of Open Access Journals (Sweden)

Marcelle Hecker

2018-02-01

Full Text Available Non-specific protein adsorption is detrimental to the performance of many biomedical devices. Polystyrene is a commonly used material in devices and thin films. Simple reliable surface modification of polystyrene to render it protein resistant is desired in particular for device fabrication and orthogonal functionalisation schemes. This report details modifications carried out on a polystyrene surface to prevent protein adsorption. The trialed surfaces included Pluronic F127 and PLL-g-PEG, adsorbed on polystyrene, using a polydopamine-assisted approach. Quartz crystal microbalance with dissipation (QCM-D results showed only short-term anti-fouling success of the polystyrene surface modified with F127, and the subsequent failure of the polydopamine intermediary layer in improving its stability. In stark contrast, QCM-D analysis proved the success of the polydopamine assisted PLL-g-PEG coating in preventing bovine serum albumin adsorption. This modified surface is equally as protein-rejecting after 24 h in buffer, and thus a promising simple coating for long term protein rejection of polystyrene.

To what extent do long-duration high-volume dam releases influence river-aquifer interactions? A case study in New South Wales, Australia

Science.gov (United States)

Graham, P. W.; Andersen, M. S.; McCabe, M. F.; Ajami, H.; Baker, A.; Acworth, I.

2015-03-01

Long-duration high-volume dam releases are unique anthropogenic events with no naturally occurring equivalents. The impact from such dam releases on a downstream Quaternary alluvial aquifer in New South Wales, Australia, is assessed. It is observed that long-duration (>26 days), high-volume dam releases (>8,000 ML/day average) result in significant variations in river-aquifer interactions. These variations include a flux from the river to the aquifer up to 6.3 m3/day per metre of bank (at distances of up to 330 m from the river bank), increased extent and volume of recharge/bank storage, and a long-term (>100 days) reversal of river-aquifer fluxes. In contrast, during lower-volume events (bank. A groundwater-head prediction model was constructed and river-aquifer fluxes were calculated; however, predicted fluxes from this method showed poor correlation to fluxes calculated using actual groundwater heads. Long-duration high-volume dam releases have the potential to skew estimates of long-term aquifer resources and detrimentally alter the chemical and physical properties of phreatic aquifers flanking the river. The findings have ramifications for improved integrated management of dam systems and downstream aquifers.

Evaluating Approaches to Rendering Braille Text on a High-Density Pin Display.

Science.gov (United States)

Morash, Valerie S; Russomanno, Alexander; Gillespie, R Brent; OModhrain, Sile

2017-10-13

Refreshable displays for tactile graphics are typically composed of pins that have smaller diameters and spacing than standard braille dots. We investigated configurations of high-density pins to form braille text on such displays using non-refreshable stimuli produced with a 3D printer. Normal dot braille (diameter 1.5 mm) was compared to high-density dot braille (diameter 0.75 mm) wherein each normal dot was rendered by high-density simulated pins alone or in a cluster of pins configured in a diamond, X, or square; and to "blobs" that could result from covering normal braille and high-density multi-pin configurations with a thin membrane. Twelve blind participants read MNREAD sentences displayed in these conditions. For high-density simulated pins, single pins were as quickly and easily read as normal braille, but diamond, X, and square multi-pin configurations were slower and/or harder to read than normal braille. We therefore conclude that as long as center-to-center dot spacing and dot placement is maintained, the dot diameter may be open to variability for rendering braille on a high density tactile display.

Efficient Algorithms for Real-Time GPU Volumetric Cloud Rendering with Enhanced Geometry

OpenAIRE

Carlos Jiménez de Parga; Sebastián Rubén Gómez Palomo

2018-01-01

This paper presents several new techniques for volumetric cloud rendering using efficient algorithms and data structures based on ray-tracing methods for cumulus generation, achieving an optimum balance between realism and performance. These techniques target applications such as flight simulations, computer games, and educational software, even with conventional graphics hardware. The contours of clouds are defined by implicit mathematical expressions or triangulated structures inside which ...

Skype me! Socially contingent interactions help toddlers learn language.

Science.gov (United States)

Roseberry, Sarah; Hirsh-Pasek, Kathy; Golinkoff, Roberta M

2014-01-01

Language learning takes place in the context of social interactions, yet the mechanisms that render social interactions useful for learning language remain unclear. This study focuses on whether social contingency might support word learning. Toddlers aged 24-30 months (N = 36) were exposed to novel verbs in one of three conditions: live interaction training, socially contingent video training over video chat, and noncontingent video training (yoked video). Results suggest that children only learned novel verbs in socially contingent interactions (live interactions and video chat). This study highlights the importance of social contingency in interactions for language learning and informs the literature on learning through screen media as the first study to examine word learning through video chat technology. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.

A matrix-free implicit unstructured multigrid finite volume method for simulating structural dynamics and fluid structure interaction

Science.gov (United States)

Lv, X.; Zhao, Y.; Huang, X. Y.; Xia, G. H.; Su, X. H.

2007-07-01

A new three-dimensional (3D) matrix-free implicit unstructured multigrid finite volume (FV) solver for structural dynamics is presented in this paper. The solver is first validated using classical 2D and 3D cantilever problems. It is shown that very accurate predictions of the fundamental natural frequencies of the problems can be obtained by the solver with fast convergence rates. This method has been integrated into our existing FV compressible solver [X. Lv, Y. Zhao, et al., An efficient parallel/unstructured-multigrid preconditioned implicit method for simulating 3d unsteady compressible flows with moving objects, Journal of Computational Physics 215(2) (2006) 661-690] based on the immersed membrane method (IMM) [X. Lv, Y. Zhao, et al., as mentioned above]. Results for the interaction between the fluid and an immersed fixed-free cantilever are also presented to demonstrate the potential of this integrated fluid-structure interaction approach.

Theoretical study for volume changes associated with the helix-coil transition of peptides.

Science.gov (United States)

Imai, T; Harano, Y; Kovalenko, A; Hirata, F

2001-12-01

We calculate the partial molar volumes and their changes associated with the coil(extended)-to-helix transition of two types of peptide, glycine-oligomer and glutamic acid-oligomer, in aqueous solutions by using the Kirkwood-Buff solution theory coupled with the three-dimensional reference interaction site model (3D-RISM) theory. The volume changes associated with the transition are small and positive. The volume is analyzed by decomposing it into five contributions following the procedure proposed by Chalikian and Breslauer: the ideal volume, the van der Waals volume, the void volume, the thermal volume, and the interaction volume. The ideal volumes and the van der Waals volumes do not change appreciably upon the transition. In the both cases of glycine-peptide and glutamic acid-peptide, the changes in the void volumes are positive, while those in the thermal volumes are negative, and tend to balance those in the void volumes. The change in the interaction volume of glycine-peptide does not significantly contribute, while that of glutamic acid-peptide makes a negative contribution. Copyright 2001 John Wiley & Sons, Inc. Biopolymers 59: 512-519, 2001

Declarative language design for interactive visualization.

Science.gov (United States)

Heer, Jeffrey; Bostock, Michael

2010-01-01

We investigate the design of declarative, domain-specific languages for constructing interactive visualizations. By separating specification from execution, declarative languages can simplify development, enable unobtrusive optimization, and support retargeting across platforms. We describe the design of the Protovis specification language and its implementation within an object-oriented, statically-typed programming language (Java). We demonstrate how to support rich visualizations without requiring a toolkit-specific data model and extend Protovis to enable declarative specification of animated transitions. To support cross-platform deployment, we introduce rendering and event-handling infrastructures decoupled from the runtime platform, letting designers retarget visualization specifications (e.g., from desktop to mobile phone) with reduced effort. We also explore optimizations such as runtime compilation of visualization specifications, parallelized execution, and hardware-accelerated rendering. We present benchmark studies measuring the performance gains provided by these optimizations and compare performance to existing Java-based visualization tools, demonstrating scalability improvements exceeding an order of magnitude.

Towards a universal method for calculating hydration free energies: a 3D reference interaction site model with partial molar volume correction

International Nuclear Information System (INIS)

Palmer, David S; Frolov, Andrey I; Ratkova, Ekaterina L; Fedorov, Maxim V

2010-01-01

We report a simple universal method to systematically improve the accuracy of hydration free energies calculated using an integral equation theory of molecular liquids, the 3D reference interaction site model. A strong linear correlation is observed between the difference of the experimental and (uncorrected) calculated hydration free energies and the calculated partial molar volume for a data set of 185 neutral organic molecules from different chemical classes. By using the partial molar volume as a linear empirical correction to the calculated hydration free energy, we obtain predictions of hydration free energies in excellent agreement with experiment (R = 0.94, σ = 0.99 kcal mol -1 for a test set of 120 organic molecules). (fast track communication)

Towards a universal method for calculating hydration free energies: a 3D reference interaction site model with partial molar volume correction.

Science.gov (United States)

Palmer, David S; Frolov, Andrey I; Ratkova, Ekaterina L; Fedorov, Maxim V

2010-12-15

We report a simple universal method to systematically improve the accuracy of hydration free energies calculated using an integral equation theory of molecular liquids, the 3D reference interaction site model. A strong linear correlation is observed between the difference of the experimental and (uncorrected) calculated hydration free energies and the calculated partial molar volume for a data set of 185 neutral organic molecules from different chemical classes. By using the partial molar volume as a linear empirical correction to the calculated hydration free energy, we obtain predictions of hydration free energies in excellent agreement with experiment (R = 0.94, σ = 0.99 kcal mol (- 1) for a test set of 120 organic molecules).

Three-dimensional rendering of otolith growth using phase contrast synchrotron tomography.

Science.gov (United States)

Mapp, J J I; Fisher, M H; Atwood, R C; Bell, G D; Greco, M K; Songer, S; Hunter, E

2016-05-01

A three-dimensional computer reconstruction of a plaice Pleuronectes platessa otolith is presented from data acquired by the Diamond Light synchrotron, beamline I12, X-ray source, a high energy (53-150 keV) source particularly well suited to the study of dense objects. The data allowed non-destructive rendering of otolith structure, and for the first time allows otolith annuli (internal ring structures) to be analysed in X-ray tomographic images. © 2016 The Fisheries Society of the British Isles.

Improving aircraft conceptual design - A PHIGS interactive graphics interface for ACSYNT

Science.gov (United States)

Wampler, S. G.; Myklebust, A.; Jayaram, S.; Gelhausen, P.

1988-01-01

A CAD interface has been created for the 'ACSYNT' aircraft conceptual design code that permits the execution and control of the design process via interactive graphics menus. This CAD interface was coded entirely with the new three-dimensional graphics standard, the Programmer's Hierarchical Interactive Graphics System. The CAD/ACSYNT system is designed for use by state-of-the-art high-speed imaging work stations. Attention is given to the approaches employed in modeling, data storage, and rendering.

Hybrid 3D visualization of the chest and virtual endoscopy of the tracheobronchial system: possibilities and limitations of clinical application.

Science.gov (United States)

Seemann, M D; Claussen, C D

2001-06-01

A hybrid rendering method which combines a color-coded surface rendering method and a volume rendering method is described, which enables virtual endoscopic examinations using different representation models. 14 patients with malignancies of the lung and mediastinum (n=11) and lung transplantation (n=3) underwent thin-section spiral computed tomography. The tracheobronchial system and anatomical and pathological features of the chest were segmented using an interactive threshold interval volume-growing segmentation algorithm and visualized with a color-coded surface rendering method. The structures of interest were then superimposed on a volume rendering of the other thoracic structures. For the virtual endoscopy of the tracheobronchial system, a shaded-surface model without color coding, a transparent color-coded shaded-surface model and a triangle-surface model were tested and compared. The hybrid rendering technique exploit the advantages of both rendering methods, provides an excellent overview of the tracheobronchial system and allows a clear depiction of the complex spatial relationships of anatomical and pathological features. Virtual bronchoscopy with a transparent color-coded shaded-surface model allows both a simultaneous visualization of an airway, an airway lesion and mediastinal structures and a quantitative assessment of the spatial relationship between these structures, thus improving confidence in the diagnosis of endotracheal and endobronchial diseases. Hybrid rendering and virtual endoscopy obviate the need for time consuming detailed analysis and presentation of axial source images. Virtual bronchoscopy with a transparent color-coded shaded-surface model offers a practical alternative to fiberoptic bronchoscopy and is particularly promising for patients in whom fiberoptic bronchoscopy is not feasible, contraindicated or refused. Furthermore, it can be used as a complementary procedure to fiberoptic bronchoscopy in evaluating airway stenosis and

Volume transmission and receptor-receptor interactions in heteroreceptor complexes: understanding the role of new concepts for brain communication

Directory of Open Access Journals (Sweden)

Kjell Fuxe

2016-01-01

Full Text Available The discovery of the central monoamine neurons not only demonstrated novel types of brain stem neurons forming global terminal networks all over the brain and the spinal cord, but also to a novel type of communication called volume transmission. It is a major mode of communication in the central nervous system that takes places in the extracellular fluid and the cerebral spinal fluid through diffusion and flow of molecules, like neurotransmitters and extracellular vesicles. The integration of synaptic and volume transmission takes place through allosteric receptor-receptor interactions in heteroreceptor complexes. These heterocomplexes represent major integrator centres in the plasma membrane and their protomers act as moonlighting proteins undergoing dynamic changes and their structure and function. In fact, we propose that the molecular bases of learning and memory can be based on the reorganization of multiples homo and heteroreceptor complexes into novel assembles in the post-junctional membranes of synapses.

Diatomic interaction potential theory applications

CERN Document Server

Goodisman, Jerry

2013-01-01

Diatomic Interaction Potential Theory, Volume 2: Applications discusses the variety of applicable theoretical material and approaches in the calculations for diatomic systems in their ground states. The volume covers the descriptions and illustrations of modern calculations. Chapter I discusses the calculation of the interaction potential for large and small values of the internuclear distance R (separated and united atom limits). Chapter II covers the methods used for intermediate values of R, which in principle means any values of R. The Hartree-Fock and configuration interaction schemes des

Molar volumes of LiI in H{sub 2}O and D{sub 2}O solutions; Structural hydration interactions

Energy Technology Data Exchange (ETDEWEB)

Jakli, Gy. [KFKI Atomic Energy Research Institute, P.O. Box 49, H-1525 Budapest (Hungary)], E-mail: jakli@aeki.kfki.hu

2009-01-15

According to a recent study of the H{sub 2}O and D{sub 2}O molar volume isotope effect (MVIE) of the alkali metal chloride solutions, neither the standard nor the excess MVIE of the LiCl corresponds to the usual hydrophilic hydration characteristics of the inorganic ions above room temperatures. This phenomenon can not be rationalized by electrostriction, with the collapse of the 'loose' tetrahedral ('ice-like') water structure due to the electrostatic (ion + dipole) interaction. It seemed possible that this unique hydration behaviour of the Li{sup +} would be stronger and could reveal further structural information with a less hydrophilic anion than the chloride. Therefore we have determined the MVIE of the LiI as a function of temperature and concentration. The densities of normal and heavy water solutions of LiI have been measured with six-figure precision at T = (288.15, 298.15, and 308.15) K from (0.03 to 4) molal, m, using a vibrating-tube densitometer. The solvent isotope effect on the apparent molar volume, as well as on the solute and solvent partial molar volumes, was evaluated. As expected, with the rationalization of the MVIE of LiI instead of the geometric structural differences of the isotopic solvents, the energetic contributions have to be considered at all the temperatures investigated. At infinite dilution, a high degree of compensation between the reversed influences of the Li{sup +} and I{sup -} on the activities of the isotopic solvents determines the MVIE. By increasing concentration, the highly asymmetric energetic interactions of the Li{sup +} and the I{sup -} with the solvent apparently result in a 'mutual salting-out' effect. At a concentration {approx}0.7m, a uniquely abrupt structural rearrangement results in a 'solvent-separated ion-pair' solution structure.

Waqf as a Tool for Rendering Social Welfare Services in the Social Entrepreneurship Context

Directory of Open Access Journals (Sweden)

Md. Mahmudul Alam

2018-01-01

Full Text Available The concept of Islamic entrepreneurship centers on ensuring community well-being as the priority, which is one of the important objectives (Maqasid of the Islamic Shari’ah. Historically, waqf played a significant role in the Islamic economic system, particularly in rendering exemplary welfare services in the areas of healthcare, education, social welfare, environmental, and other community-based programs. However, only a few success stories in recent history have institutionally utilized the properties of waqf under proper management to achieve its substantial objectives. This study uses the literature review as basis to analyze the reasons behind the successful utilization of waqf as an effective tool to ensure social welfare services in the past, as well as how this model can be replicated by considering current contexts. This study will assist Islamic valuecentric entrepreneurs, regulatory authorities, investors, and researchers to gain an overall insight into the potentials of waqf as a tool for rendering commendable social welfare services.

Comparison of gesture and conventional interaction techniques for interventional neuroradiology.

Science.gov (United States)

Hettig, Julian; Saalfeld, Patrick; Luz, Maria; Becker, Mathias; Skalej, Martin; Hansen, Christian

2017-09-01

Interaction with radiological image data and volume renderings within a sterile environment is a challenging task. Clinically established methods such as joystick control and task delegation can be time-consuming and error-prone and interrupt the workflow. New touchless input modalities may have the potential to overcome these limitations, but their value compared to established methods is unclear. We present a comparative evaluation to analyze the value of two gesture input modalities (Myo Gesture Control Armband and Leap Motion Controller) versus two clinically established methods (task delegation and joystick control). A user study was conducted with ten experienced radiologists by simulating a diagnostic neuroradiological vascular treatment with two frequently used interaction tasks in an experimental operating room. The input modalities were assessed using task completion time, perceived task difficulty, and subjective workload. Overall, the clinically established method of task delegation performed best under the study conditions. In general, gesture control failed to exceed the clinical input approach. However, the Myo Gesture Control Armband showed a potential for simple image selection task. Novel input modalities have the potential to take over single tasks more efficiently than clinically established methods. The results of our user study show the relevance of task characteristics such as task complexity on performance with specific input modalities. Accordingly, future work should consider task characteristics to provide a useful gesture interface for a specific use case instead of an all-in-one solution.

Metastable decoherence-free subspaces and electromagnetically induced transparency in interacting many-body systems

DEFF Research Database (Denmark)

Macieszczak, Katarzyna; Zhou, Yanli; Hofferberth, Sebastian

2017-01-01

to stationarity this leads to a slow dynamics, which renders the typical assumption of fast relaxation invalid. We derive analytically the effective nonequilibrium dynamics in the decoherence-free subspace, which features coherent and dissipative two-body interactions. We discuss the use of this scenario...

Four-dimensional ultrasonography of the fetal heart with spatiotemporal image correlation.

Science.gov (United States)

Gonçalves, Luís F; Lee, Wesley; Chaiworapongsa, Tinnakorn; Espinoza, Jimmy; Schoen, Mary Lou; Falkensammer, Peter; Treadwell, Marjorie; Romero, Roberto

2003-12-01

This study was undertaken to describe a new technique for the examination of the fetal heart using four-dimensional ultrasonography with spatiotemporal image correlation (STIC). Volume data sets of the fetal heart were acquired with a new cardiac gating technique (STIC), which uses automated transverse and longitudinal sweeps of the anterior chest wall. These volumes were obtained from 69 fetuses: 35 normal, 16 with congenital anomalies not affecting the cardiovascular system, and 18 with cardiac abnormalities. Dynamic multiplanar slicing and surface rendering of cardiac structures were performed. To illustrate the STIC technique, two representative volumes from a normal fetus were compared with volumes obtained from fetuses with the following congenital heart anomalies: atrioventricular septal defect, tricuspid stenosis, tricuspid atresia, and interrupted inferior vena cava with abnormal venous drainage. Volume datasets obtained with a transverse sweep were utilized to demonstrate the cardiac chambers, moderator band, interatrial and interventricular septae, atrioventricular valves, pulmonary veins, and outflow tracts. With the use of a reference dot to navigate the four-chamber view, intracardiac structures could be simultaneously studied in three orthogonal planes. The same volume dataset was used for surface rendering of the atrioventricular valves. The aortic and ductal arches were best visualized when the original plane of acquisition was sagittal. Volumes could be interactively manipulated to simultaneously visualize both outflow tracts, in addition to the aortic and ductal arches. Novel views of specific structures were generated. For example, the location and extent of a ventricular septal defect was imaged in a sagittal view of the interventricular septum. Furthermore, surface-rendered images of the atrioventricular valves were employed to distinguish between normal and pathologic conditions. Representative video clips were posted on the Journal's Web

Transient analysis of electromagnetic wave interactions on high-contrast scatterers using volume electric field integral equation

KAUST Repository

Sayed, Sadeed Bin

2014-07-01

A marching on-in-time (MOT)-based time domain volume electric field integral equation (TD-VEFIE) solver is proposed for accurate and stable analysis of electromagnetic wave interactions on high-contrast scatterers. The stability is achieved using band-limited but two-sided (non-causal) temporal interpolation functions and an extrapolation scheme to cast the time marching into a causal form. The extrapolation scheme is designed to be highly accurate for oscillating and exponentially decaying fields, hence it accurately captures the physical behavior of the resonant modes that are excited inside the dielectric scatterer. Numerical results demonstrate that the resulting MOT scheme maintains its stability as the number of resonant modes increases with the contrast of the scatterer.

ASEAN--USAID Buildings Energy Conservation Project final report. Volume 2, Technology

Energy Technology Data Exchange (ETDEWEB)

Levine, M.D.; Busch, J.F. [eds.

1992-06-01

This volume reports on research in the area of energy conservation technology applied to commercial buildings in the Association of Southeast Asian Nations (ASEAN) region. Unlike Volume I of this series, this volume is a compilation of original technical papers prepared by different authors in the project. In this regard, this volume is much like a technical journal. The papers that follow report on research conducted by both US and ASEAN researchers. The authors representing Indonesia, Malaysia, Philippines, and Thailand, come from a range of positions in the energy arena, including government energy agencies, electric utilities, and universities. As such, they account for a wide range of perspectives on energy problems and the role that technology can play in solving them. This volume is about using energy more intelligently. In some cases, the effort is towards the use of more advanced technologies, such as low-emittance coatings on window glass, thermal energy storage, or cogeneration. In others, the emphasis is towards reclaiming traditional techniques for rendering energy services, but in new contexts such as lighting office buildings with natural light, or cooling buildings of all types with natural ventilation. Used in its broadest sense, the term ``technology`` encompasses all of the topics addressed in this volume. Along with the more customary associations of technology, such as advanced materials and equipment and the analysis of their performance, this volume treats design concepts and techniques, analysis of ``secondary`` impacts from applying technologies (i.e., unintended impacts, or impacts on parties not directly involved in the purchase and use of the technology), and the collection of primary data used for conducting technical analyses.

Interactive Mapping on Virtual Terrain Models Using RIMS (Real-time, Interactive Mapping System)

Science.gov (United States)

Bernardin, T.; Cowgill, E.; Gold, R. D.; Hamann, B.; Kreylos, O.; Schmitt, A.

2006-12-01

Recent and ongoing space missions are yielding new multispectral data for the surfaces of Earth and other planets at unprecedented rates and spatial resolution. With their high spatial resolution and widespread coverage, these data have opened new frontiers in observational Earth and planetary science. But they have also precipitated an acute need for new analytical techniques. To address this problem, we have developed RIMS, a Real-time, Interactive Mapping System that allows scientists to visualize, interact with, and map directly on, three-dimensional (3D) displays of georeferenced texture data, such as multispectral satellite imagery, that is draped over a surface representation derived from digital elevation data. The system uses a quadtree-based multiresolution method to render in real time high-resolution (3 to 10 m/pixel) data over large (800 km by 800 km) spatial areas. It allows users to map inside this interactive environment by generating georeferenced and attributed vector-based elements that are draped over the topography. We explain the technique using 15 m ASTER stereo-data from Iraq, P.R. China, and other remote locations because our particular motivation is to develop a technique that permits the detailed (10 m to 1000 m) neotectonic mapping over large (100 km to 1000 km long) active fault systems that is needed to better understand active continental deformation on Earth. RIMS also includes a virtual geologic compass that allows users to fit a plane to geologic surfaces and thereby measure their orientations. It also includes tools that allow 3D surface reconstruction of deformed and partially eroded surfaces such as folded bedding planes. These georeferenced map and measurement data can be exported to, or imported from, a standard GIS (geographic information systems) file format. Our interactive, 3D visualization and analysis system is designed for those who study planetary surfaces, including neotectonic geologists, geomorphologists, marine

Effect of nanostructured lime-based and silica-based products on the consolidation of historical renders

NARCIS (Netherlands)

Borsoi, G.; Veiga, R.; Santos Silva, A.

2013-01-01

An important operation for the conservation of historical renders is the cohesion restitution of the binderaggregate system, based on the use of materials with consolidating properties. Inorganic consolidants are usually preferred to organic ones due to better compatibility and durability. The aim

Radionuclide cisternography: SPECT and 3D-rendering. Radionuklidzisternographie: SPECT- und 3D-Technik

Energy Technology Data Exchange (ETDEWEB)

Henkes, H; Huber, G; Piepgras, U [Universitaet des Saarlandes, Homburg/Saar (Germany, F.R.). Abt. fuer Neuroradiologie; Hierholzer, J [Freie Univ. Berlin (Germany, F.R.). Strahlenklinik und Poliklinik; Cordes, M [British Columbia Univ., Vancouver, BC (Canada). Belzberg Lab. of Neuroscience

1991-10-01

Radionuclide cisternography is indicated in the clinical work-up for hydrocephalus, when searching for CSF leaks, and when testing whether or not intracranial cystic lesions are communicating with the adjacent subarachnoid space. This paper demonstrates the feasibility and diagnostic value of SPECT and subsequent 3D surface rendering in addition to conventional rectilinear CSF imaging in eight patients. Planar images allowed the evaluation of CSF circulation and the detection of CSF fistula. They were advantageous in examinations 48 h after application of {sup 111}In-DTPA. SPECT scans, generated 4-24 h after tracer application, were superior in the delineation of basal cisterns, especially in early scans; this was helpful in patients with pooling due to CSF fistula and in cystic lesions near the skull base. A major drawback was the limited image quality of delayed scans, when the SPECT data were degraded by a low count rate. 3D surface rendering was easily feasible from SPECT data and yielded high quality images. The presentation of the spatial distribution of nuclide-contaminated CSF proved especially helpful in the area of the basal cisterns. (orig.).

Comparative analysis of video processing and 3D rendering for cloud video games using different virtualization technologies

Science.gov (United States)

Bada, Adedayo; Alcaraz-Calero, Jose M.; Wang, Qi; Grecos, Christos

2014-05-01

This paper describes a comprehensive empirical performance evaluation of 3D video processing employing the physical/virtual architecture implemented in a cloud environment. Different virtualization technologies, virtual video cards and various 3D benchmarks tools have been utilized in order to analyse the optimal performance in the context of 3D online gaming applications. This study highlights 3D video rendering performance under each type of hypervisors, and other factors including network I/O, disk I/O and memory usage. Comparisons of these factors under well-known virtual display technologies such as VNC, Spice and Virtual 3D adaptors reveal the strengths and weaknesses of the various hypervisors with respect to 3D video rendering and streaming.

A Semi-automated Approach to Improve the Efficiency of Medical Imaging Segmentation for Haptic Rendering.

Science.gov (United States)

Banerjee, Pat; Hu, Mengqi; Kannan, Rahul; Krishnaswamy, Srinivasan

2017-08-01

The Sensimmer platform represents our ongoing research on simultaneous haptics and graphics rendering of 3D models. For simulation of medical and surgical procedures using Sensimmer, 3D models must be obtained from medical imaging data, such as magnetic resonance imaging (MRI) or computed tomography (CT). Image segmentation techniques are used to determine the anatomies of interest from the images. 3D models are obtained from segmentation and their triangle reduction is required for graphics and haptics rendering. This paper focuses on creating 3D models by automating the segmentation of CT images based on the pixel contrast for integrating the interface between Sensimmer and medical imaging devices, using the volumetric approach, Hough transform method, and manual centering method. Hence, automating the process has reduced the segmentation time by 56.35% while maintaining the same accuracy of the output at ±2 voxels.

Calibration of a dedicated software for 3D rendering

Energy Technology Data Exchange (ETDEWEB)

Abrantes, Marcos E.S.; Felix, Warley F.; Veloso, Maria Auxiliadora F., E-mail: marcos.nuclear@yahoo.com.br, E-mail: warleyferreirafelix@gmail.com, E-mail: mdora@nuclear.ufmg.br [Faculdade Ciencias Medicas de Minas Gerais (FCMMG), Belo Horizonte, MG (Brazil); Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

2017-11-01

With the increasing use of 3D reconstruction techniques, to assist in diagnosis, dedicated programs are being widely used. For this they must be calibrated in order to encounter the values of the real volumes of the human tissues. The purpose of this work is to indicate correction and calibration values for true volumes, read in a 3D reconstruction system dedicated, using DICOM images of Computed Tomography. This work utilized a PMMA thorax phantom associated with the DICOM image and the volume found by a program of a tomograph. The physical volume of the PMMA phantom found was 10359.0 cm³. For the volumes found according to the structures of interest, the values are 11005.5 cm³, 10249.3 cm³ and 10205.1 cm³ and the correction values are -6.2%, +1.1% e +1.5% respectively for tissues: pulmonary, bony and soft tissues. The procedure performed can be used for calibration in other 3D reconstruction programs, observing the necessary corrections and the methodology used. (author)

Calibration of a dedicated software for 3D rendering

International Nuclear Information System (INIS)

Abrantes, Marcos E.S.; Felix, Warley F.; Veloso, Maria Auxiliadora F.; Universidade Federal de Minas Gerais

2017-01-01

With the increasing use of 3D reconstruction techniques, to assist in diagnosis, dedicated programs are being widely used. For this they must be calibrated in order to encounter the values of the real volumes of the human tissues. The purpose of this work is to indicate correction and calibration values for true volumes, read in a 3D reconstruction system dedicated, using DICOM images of Computed Tomography. This work utilized a PMMA thorax phantom associated with the DICOM image and the volume found by a program of a tomograph. The physical volume of the PMMA phantom found was 10359.0 cm³. For the volumes found according to the structures of interest, the values are 11005.5 cm³, 10249.3 cm³ and 10205.1 cm³ and the correction values are -6.2%, +1.1% e +1.5% respectively for tissues: pulmonary, bony and soft tissues. The procedure performed can be used for calibration in other 3D reconstruction programs, observing the necessary corrections and the methodology used. (author)

Strength of tensor force and s-d-shell effective interactions

International Nuclear Information System (INIS)

Jiang, M.; Machleidt, R.; Stout, D.B.; Kuo, T.T.S.

1989-01-01

The s-d-shell effective interaction is derived from the Bonn NN potential, using a G-matrix folded-diagram method. It is found that due to the relatively weak-tensor-force characteristic for the Bonn potential, the effective interaction matrix elements, particularly those with isospin T=0, come out generally more attractive than in previous derivations which were based on conventional local strong-tensor-force NN potentials. This renders the results obtained with the Bonn potential in considerably better agreement with the recent s-d-shell matrix elements of Wildenthal

User evaluation of eight led light sources with different special colour rendering indices R9

DEFF Research Database (Denmark)

Markvart, Jakob; Iversen, Anne; Logadottir, Asta

2013-01-01

In this study we evaluated the influence of the special colour rendering index R9 on subjective red colour perception and Caucasian skin appearance among untrained test subjects. The light sources tested are commercially available LED based light sources with similar correlated colour temperature...

To what extent do long-duration high-volume dam releases influence river–aquifer interactions? A case study in New South Wales, Australia

KAUST Repository

Graham, Peter W.

2014-11-20

Long-duration high-volume dam releases are unique anthropogenic events with no naturally occurring equivalents. The impact from such dam releases on a downstream Quaternary alluvial aquifer in New South Wales, Australia, is assessed. It is observed that long-duration (>26 days), high-volume dam releases (>8,000 ML/day average) result in significant variations in river–aquifer interactions. These variations include a flux from the river to the aquifer up to 6.3 m3/day per metre of bank (at distances of up to 330 m from the river bank), increased extent and volume of recharge/bank storage, and a long-term (>100 days) reversal of river–aquifer fluxes. In contrast, during lower-volume events (<2,000 ML/day average) the flux was directed from the aquifer to the river at rates of up to 1.6 m3/day per metre of bank. A groundwater-head prediction model was constructed and river–aquifer fluxes were calculated; however, predicted fluxes from this method showed poor correlation to fluxes calculated using actual groundwater heads. Long-duration high-volume dam releases have the potential to skew estimates of long-term aquifer resources and detrimentally alter the chemical and physical properties of phreatic aquifers flanking the river. The findings have ramifications for improved integrated management of dam systems and downstream aquifers.

Latency in Distributed Acquisition and Rendering for Telepresence Systems.

Science.gov (United States)

Ohl, Stephan; Willert, Malte; Staadt, Oliver

2015-12-01

Telepresence systems use 3D techniques to create a more natural human-centered communication over long distances. This work concentrates on the analysis of latency in telepresence systems where acquisition and rendering are distributed. Keeping latency low is important to immerse users in the virtual environment. To better understand latency problems and to identify the source of such latency, we focus on the decomposition of system latency into sub-latencies. We contribute a model of latency and show how it can be used to estimate latencies in a complex telepresence dataflow network. To compare the estimates with real latencies in our prototype, we modify two common latency measurement methods. This presented methodology enables the developer to optimize the design, find implementation issues and gain deeper knowledge about specific sources of latency.

Individual differences in posterior cortical volume correlate with proneness to pride and gratitude.

Science.gov (United States)

Zahn, Roland; Garrido, Griselda; Moll, Jorge; Grafman, Jordan

2014-11-01

Proneness to specific moral sentiments (e.g. pride, gratitude, guilt, indignation) has been linked with individual variations in functional MRI (fMRI) response within anterior brain regions whose lesion leads to inappropriate behaviour. However, the role of structural anatomical differences in rendering individuals prone to particular moral sentiments relative to others is unknown. Here, we investigated grey matter volumes (VBM8) and proneness to specific moral sentiments on a well-controlled experimental task in healthy individuals. Individuals with smaller cuneus, and precuneus volumes were more pride-prone, whereas those with larger right inferior temporal volumes experienced gratitude more readily. Although the primary analysis detected no associations with guilt- or indignation-proneness, subgenual cingulate fMRI responses to guilt were negatively correlated with grey matter volumes in the left superior temporal sulcus and anterior dorsolateral prefrontal cortices (right >left). This shows that individual variations in functional activations within critical areas for moral sentiments were not due to grey matter volume differences in the same areas. Grey matter volume differences between healthy individuals may nevertheless play an important role by affecting posterior cortical brain systems that are non-critical but supportive for the experience of specific moral sentiments. This may be of particular relevance when their experience depends on visuo-spatial elaboration. Published by Oxford University Press 2013. This work is written by US Government employees and is in the public domain in the US.

Application of bacteriophages to reduce biofilms formed by hydrogen sulfide producing bacteria on surfaces in a rendering plant.

Science.gov (United States)

Gong, Chao; Jiang, Xiuping

2015-08-01

Hydrogen sulfide producing bacteria (SPB) in raw animal by-products are likely to grow and form biofilms in the rendering processing environments, resulting in the release of harmful hydrogen sulfide (H2S) gas. The objective of this study was to reduce SPB biofilms formed on different surfaces typically found in rendering plants by applying a bacteriophage cocktail. Using a 96-well microplate method, we determined that 3 SPB strains of Citrobacter freundii and Hafnia alvei are strong biofilm formers. Application of 9 bacteriophages (10(7) PFU/mL) from families of Siphoviridae and Myoviridae resulted in a 33%-70% reduction of biofilm formation by each SPB strain. On stainless steel and plastic templates, phage treatment (10(8) PFU/mL) reduced the attached cells of a mixed SPB culture (no biofilm) by 2.3 and 2.7 log CFU/cm(2) within 6 h at 30 °C, respectively, as compared with 2 and 1.5 log CFU/cm(2) reductions of SPB biofilms within 6 h at 30 °C. Phage treatment was also applied to indigenous SPB biofilms formed on the environmental surface, stainless steel, high-density polyethylene plastic, and rubber templates in a rendering plant. With phage treatment (10(9) PFU/mL), SPB biofilms were reduced by 0.7-1.4, 0.3-0.6, and 0.2-0.6 log CFU/cm(2) in spring, summer, and fall trials, respectively. Our study demonstrated that bacteriophages could effectively reduce the selected SPB strains either attached to or in formed biofilms on various surfaces and could to some extent reduce the indigenous SPB biofilms on the surfaces in the rendering environment.

Self-consistent field theory of tethered polymers: one dimensional, three dimensional, strong stretching theories and the effects of excluded-volume-only interactions.

Science.gov (United States)

Suo, Tongchuan; Whitmore, Mark D

2014-11-28

We examine end-tethered polymers in good solvents, using one- and three-dimensional self-consistent field theory, and strong stretching theories. We also discuss different tethering scenarios, namely, mobile tethers, fixed but random ones, and fixed but ordered ones, and the effects and important limitations of including only binary interactions (excluded volume terms). We find that there is a "mushroom" regime in which the layer thickness is independent of the tethering density, σ, for systems with ordered tethers, but we argue that there is no such plateau for mobile or disordered anchors, nor is there one in the 1D theory. In the other limit of brushes, all approaches predict that the layer thickness scales linearly with N. However, the σ(1/3) scaling is a result of keeping only excluded volume interactions: when the full potential is included, the dependence is faster and more complicated than σ(1/3). In fact, there does not appear to be any regime in which the layer thickness scales in the combination Nσ(1/3). We also compare the results for two different solvents with each other, and with earlier Θ solvent results.

Self-consistent field theory of tethered polymers: One dimensional, three dimensional, strong stretching theories and the effects of excluded-volume-only interactions

International Nuclear Information System (INIS)

Suo, Tongchuan; Whitmore, Mark D.

2014-01-01

We examine end-tethered polymers in good solvents, using one- and three-dimensional self-consistent field theory, and strong stretching theories. We also discuss different tethering scenarios, namely, mobile tethers, fixed but random ones, and fixed but ordered ones, and the effects and important limitations of including only binary interactions (excluded volume terms). We find that there is a “mushroom” regime in which the layer thickness is independent of the tethering density, σ, for systems with ordered tethers, but we argue that there is no such plateau for mobile or disordered anchors, nor is there one in the 1D theory. In the other limit of brushes, all approaches predict that the layer thickness scales linearly with N. However, the σ 1/3 scaling is a result of keeping only excluded volume interactions: when the full potential is included, the dependence is faster and more complicated than σ 1/3 . In fact, there does not appear to be any regime in which the layer thickness scales in the combination Nσ 1/3 . We also compare the results for two different solvents with each other, and with earlier Θ solvent results

Numerical Cerebrospinal System Modeling in Fluid-Structure Interaction.

Science.gov (United States)

Garnotel, Simon; Salmon, Stéphanie; Balédent, Olivier

2018-01-01

Cerebrospinal fluid (CSF) stroke volume in the aqueduct is widely used to evaluate CSF dynamics disorders. In a healthy population, aqueduct stroke volume represents around 10% of the spinal stroke volume while intracranial subarachnoid space stroke volume represents 90%. The amplitude of the CSF oscillations through the different compartments of the cerebrospinal system is a function of the geometry and the compliances of each compartment, but we suspect that it could also be impacted be the cardiac cycle frequency. To study this CSF distribution, we have developed a numerical model of the cerebrospinal system taking into account cerebral ventricles, intracranial subarachnoid spaces, spinal canal and brain tissue in fluid-structure interactions. A numerical fluid-structure interaction model is implemented using a finite-element method library to model the cerebrospinal system and its interaction with the brain based on fluid mechanics equations and linear elasticity equations coupled in a monolithic formulation. The model geometry, simplified in a first approach, is designed in accordance with realistic volume ratios of the different compartments: a thin tube is used to mimic the high flow resistance of the aqueduct. CSF velocity and pressure and brain displacements are obtained as simulation results, and CSF flow and stroke volume are calculated from these results. Simulation results show a significant variability of aqueduct stroke volume and intracranial subarachnoid space stroke volume in the physiological range of cardiac frequencies. Fluid-structure interactions are numerous in the cerebrospinal system and difficult to understand in the rigid skull. The presented model highlights significant variations of stroke volumes under cardiac frequency variations only.

Soft interactions and volume exclusion by polymeric crowders can stabilize or destabilize transient structure in disordered proteins depending on polymer concentration.

Science.gov (United States)

Rusinga, Farai I; Weis, David D

2017-08-01

The effects of macromolecular crowding on the transient structure of intrinsically disordered proteins is not well-understood. Crowding by biological molecules inside cells could modulate transient structure and alter IDP function. Volume exclusion theory and observations of structured proteins suggest that IDP transient structure would be stabilized by macromolecular crowding. Amide hydrogen exchange (HX) of IDPs in highly concentrated polymer solutions would provide valuable insights into IDP transient structure under crowded conditions. Here, we have used mass spectrometry to measure HX by a transiently helical random coil domain of the activator of thyroid and retinoid receptor (ACTR) in solutions containing 300 g L -1 and 400 g L -1 of Ficoll, a synthetic polysaccharide, using a recently-developed strong cation exchange-based cleanup method [Rusinga, et al., Anal Chem 2017;89:1275-1282]. Transiently helical regions of ACTR exchanged faster in 300 g L -1 Ficoll than in dilute buffer. In contrast, one transient helix exchanged more slowly in 400 g L -1 Ficoll. Nonspecific interactions destabilize ACTR helicity in 300 g L -1 Ficoll because ACTR engages with the Ficoll polymer mesh. In contrast, 400 g L -1 Ficoll is a semi-dilute solution where ACTR cannot engage the Ficoll mesh. At this higher concentration, volume exclusion stabilizes ACTR helicity because ACTR is compacted in interstitial spaces between Ficoll molecules. Our results suggest that the interplay between nonspecific interactions and volume exclusion in different cellular compartments could modulate IDP function by altering the stability of IDP transient structures. Proteins 2017; 85:1468-1479. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Gender dimorphism of brain reward system volumes in alcoholism.

Science.gov (United States)

Sawyer, Kayle S; Oscar-Berman, Marlene; Barthelemy, Olivier J; Papadimitriou, George M; Harris, Gordon J; Makris, Nikos

2017-05-30

The brain's reward network has been reported to be smaller in alcoholic men compared to nonalcoholic men, but little is known about the volumes of reward regions in alcoholic women. Morphometric analyses were performed on magnetic resonance brain scans of 60 long-term chronic alcoholics (ALC; 30 men) and 60 nonalcoholic controls (NC; 29 men). We derived volumes of total brain, and cortical and subcortical reward-related structures including the dorsolateral prefrontal (DLPFC), orbitofrontal, and cingulate cortices, and the temporal pole, insula, amygdala, hippocampus, nucleus accumbens septi (NAc), and ventral diencephalon (VDC). We examined the relationships of the volumetric findings to drinking history. Analyses revealed a significant gender interaction for the association between alcoholism and total reward network volumes, with ALC men having smaller reward volumes than NC men and ALC women having larger reward volumes than NC women. Analyses of a priori subregions revealed a similar pattern of reward volume differences with significant gender interactions for DLPFC and VDC. Overall, the volume of the cerebral ventricles in ALC participants was negatively associated with duration of abstinence, suggesting decline in atrophy with greater length of sobriety. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Improved wrist pannus volume measurement from contrast-enhanced MRI in rheumatoid arthritis using shuffle transform.

Science.gov (United States)

Xanthopoulos, Emily; Hutchinson, Charles E; Adams, Judith E; Bruce, Ian N; Nash, Anthony F P; Holmes, Andrew P; Taylor, Christopher J; Waterton, John C

2007-01-01

Contrast-enhanced MRI is of value in assessing rheumatoid pannus in the hand, but the images are not always easy to quantitate. To develop and evaluate an improved measurement of volume of enhancing pannus (VEP) in the hand in human rheumatoid arthritis (RA). MR images of the hand and wrist were obtained for 14 patients with RA at 0, 1 and 13 weeks. Volume of enhancing pannus was measured on images created by subtracting precontrast T1-weighted images from contrast-enhanced T1-weighted images using a shuffle transformation technique. Maximum intensity projection (MIP) and 3D volume rendering of the images were used as a guide to identify the pannus and any contrast-enhanced veins. Visualisation of pannus was much improved following the shuffle transform. Between 0 weeks and 1 week, the mean value of the within-subject coefficient of variation (CoV) was 0.13 and the estimated total CoV was 0.15. There was no evidence of significant increased variability within the 13-week interval for the complete sample of patients. Volume of enhancing pannus can be measured reproducibly in the rheumatoid hand using 3D contrast-enhanced MRI and shuffle transform.

Computing volume potentials for noninvasive imaging of cardiac excitation.

Science.gov (United States)

van der Graaf, A W Maurits; Bhagirath, Pranav; van Driel, Vincent J H M; Ramanna, Hemanth; de Hooge, Jacques; de Groot, Natasja M S; Götte, Marco J W

2015-03-01

In noninvasive imaging of cardiac excitation, the use of body surface potentials (BSP) rather than body volume potentials (BVP) has been favored due to enhanced computational efficiency and reduced modeling effort. Nowadays, increased computational power and the availability of open source software enable the calculation of BVP for clinical purposes. In order to illustrate the possible advantages of this approach, the explanatory power of BVP is investigated using a rectangular tank filled with an electrolytic conductor and a patient specific three dimensional model. MRI images of the tank and of a patient were obtained in three orthogonal directions using a turbo spin echo MRI sequence. MRI images were segmented in three dimensional using custom written software. Gmsh software was used for mesh generation. BVP were computed using a transfer matrix and FEniCS software. The solution for 240,000 nodes, corresponding to a resolution of 5 mm throughout the thorax volume, was computed in 3 minutes. The tank experiment revealed that an increased electrode surface renders the position of the 4 V equipotential plane insensitive to mesh cell size and reduces simulated deviations. In the patient-specific model, the impact of assigning a different conductivity to lung tissue on the distribution of volume potentials could be visualized. Generation of high quality volume meshes and computation of BVP with a resolution of 5 mm is feasible using generally available software and hardware. Estimation of BVP may lead to an improved understanding of the genesis of BSP and sources of local inaccuracies. © 2014 Wiley Periodicals, Inc.

Efficient transmission of compressed data for remote volume visualization.

Science.gov (United States)

Krishnan, Karthik; Marcellin, Michael W; Bilgin, Ali; Nadar, Mariappan S

2006-09-01

One of the goals of telemedicine is to enable remote visualization and browsing of medical volumes. There is a need to employ scalable compression schemes and efficient client-server models to obtain interactivity and an enhanced viewing experience. First, we present a scheme that uses JPEG2000 and JPIP (JPEG2000 Interactive Protocol) to transmit data in a multi-resolution and progressive fashion. The server exploits the spatial locality offered by the wavelet transform and packet indexing information to transmit, in so far as possible, compressed volume data relevant to the clients query. Once the client identifies its volume of interest (VOI), the volume is refined progressively within the VOI from an initial lossy to a final lossless representation. Contextual background information can also be made available having quality fading away from the VOI. Second, we present a prioritization that enables the client to progressively visualize scene content from a compressed file. In our specific example, the client is able to make requests to progressively receive data corresponding to any tissue type. The server is now capable of reordering the same compressed data file on the fly to serve data packets prioritized as per the client's request. Lastly, we describe the effect of compression parameters on compression ratio, decoding times and interactivity. We also present suggestions for optimizing JPEG2000 for remote volume visualization and volume browsing applications. The resulting system is ideally suited for client-server applications with the server maintaining the compressed volume data, to be browsed by a client with a low bandwidth constraint.

Temporally rendered automatic cloud extraction (TRACE) system

Science.gov (United States)

Bodrero, Dennis M.; Yale, James G.; Davis, Roger E.; Rollins, John M.

1999-10-01

Smoke/obscurant testing requires that 2D cloud extent be extracted from visible and thermal imagery. These data are used alone or in combination with 2D data from other aspects to make 3D calculations of cloud properties, including dimensions, volume, centroid, travel, and uniformity. Determining cloud extent from imagery has historically been a time-consuming manual process. To reduce time and cost associated with smoke/obscurant data processing, automated methods to extract cloud extent from imagery were investigated. The TRACE system described in this paper was developed and implemented at U.S. Army Dugway Proving Ground, UT by the Science and Technology Corporation--Acuity Imaging Incorporated team with Small Business Innovation Research funding. TRACE uses dynamic background subtraction and 3D fast Fourier transform as primary methods to discriminate the smoke/obscurant cloud from the background. TRACE has been designed to run on a PC-based platform using Windows. The PC-Windows environment was chosen for portability, to give TRACE the maximum flexibility in terms of its interaction with peripheral hardware devices such as video capture boards, removable media drives, network cards, and digital video interfaces. Video for Windows provides all of the necessary tools for the development of the video capture utility in TRACE and allows for interchangeability of video capture boards without any software changes. TRACE is designed to take advantage of future upgrades in all aspects of its component hardware. A comparison of cloud extent determined by TRACE with manual method is included in this paper.