Top PDF Real-time visualization of joint cavitation.

Real-time visualization of joint cavitation.

Real-time visualization of joint cavitation.

Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortu- nately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse. In this study, ten metacarpophalangeal joints were studied by inserting the finger of interest into a flexible tube tightened around a length of cable used to provide long-axis traction. Before and after traction, static 3D T1- weighted magnetic resonance images were acquired. During traction, rapid cine magnetic resonance images were obtained from the joint midline at a rate of 3.2 frames per second until the cracking event occurred. As traction forces increased, real-time cine magnetic res- onance imaging demonstrated rapid cavity inception at the time of joint separation and sound production after which the resulting cavity remained visible. Our results offer direct experimental evidence that joint cracking is associated with cavity inception rather than col- lapse of a pre-existing bubble. These observations are consistent with tribonucleation, a known process where opposing surfaces resist separation until a critical point where they then separate rapidly creating sustained gas cavities. Observed previously in vitro, this is the first in-vivo macroscopic demonstration of tribonucleation and as such, provides a new theoretical framework to investigate health outcomes associated with joint cracking.
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Real-time whole-body visualization of Chikungunya Virus infection and host interferon response in zebrafish.

Real-time whole-body visualization of Chikungunya Virus infection and host interferon response in zebrafish.

We monitored organs and cells of live CHIKV-GFP infected zebrafish. GFP patterns varied through time (Figure 1D) and between individuals (Figure S1B in Text S1). GFP was detected in liver, jaw, gills, vascular endothelium, eyes, fins, blood cells, muscle fibers, brain, spinal cord, swim bladder and the yolk syncytial layer. Similar patterns were observed in CHIKV-115 infected zebrafish after fixation and immunohistochemistry (IHC) with a capsid-specific antibody (not shown). We quantified the distribution of infected cells in the entire organism over time to establish the kinetics of viral dissemination (Figure 1E). The amount of infected cells peaked by 1–2 dpi in most organs (jaw, fins, liver, vessels, musculature). This peak was followed by a sharp decrease both in the frequency of larvae showing infection in a given organ, and the number of infected cells per organ. By 4 dpi, CHIKV was cleared from most organs. In contrast, infection in the brain parenchyma became visible at 2 dpi in most animals and persisted at least until 5 dpi (Figures 1D and 1E), suggesting that the brain may represent a viral reservoir in zebrafish. At 7 dpi, the latest time point testable, infection in the brain was still strong (Figure S1C in Text S1); in addition, double staining of CHIKV-GFP infected larvae with anti-GFP and anti-capsid antibodies showed that almost all capsid-positive cells also expressed GFP, indicating that GFP expression was a reliable indicator of the infection, even into late stages.
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Data visualization techniques for real-time information — A custom and dynamic dashboard for analyzing surveys' results

Data visualization techniques for real-time information — A custom and dynamic dashboard for analyzing surveys' results

Throughout the years, several authors have addressed information visualization techniques as a tool to help in the decision making and service management activities. For instance, the work presented in “A Survey on Information Visualization for Network and Service Management” [4] offers a survey in the use of information visualization techniques as a tool to support the network and service management process; while “The Visual Display of Quantitative Information” [5] provides a study and literature review of the visual display of quantitative information. Several research papers carry out similar studies, which allows to determine that the current research will be helpful in the scientific and academic community.
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Dashboard design to assess the impact of distinct data visualization techniques in the dynamic analysis of survey’s results

Dashboard design to assess the impact of distinct data visualization techniques in the dynamic analysis of survey’s results

Abstract — To achieve the most understandable and accurate display of information, a study on the available techniques of data visualization for real-time information must be made. Customizing existing platforms and designing specific boards, are among the important task to perform an accurate visualization of the information. In this paper, we conduct a literature review of data visualization, its techniques and existing Dashboard platforms. We implemented a generic and dynamic Dashboard based on real-time information with the aim to assess the impact of the available Data Visualization Techniques in the developed Dashboard. Therefore, our Dashboard users will be able to interact with the information, based on an initial set of hints, charts, tables and reports, produced by the Dashboard itself. This will allow us to test an existing set of data visualization techniques and create a new tailored Dashboard, showing that Dashboards can become a unique and powerful means to provide information.
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Arq. Bras. Cardiol.  vol.96 número1 en v96n1a19

Arq. Bras. Cardiol. vol.96 número1 en v96n1a19

The intracardiac echocardiography (ICE) offers a detailed visualization of the cardiac structures, in association with hemodynamic information, allowing the precise and real-time positioning of the catheters, decreasing the time of exposure to fluoroscopy and the monitoring of acute complications during the electrophysiological procedure (i.e., formation of thrombi, pericardial effusion, cardiac tamponade), Consequently, its use has progressively increased, mainly in the ablation of atrial fibrillation and ventricular arrhythmias. It has shown to be very useful in the ablation of atrial fibrillation by providing anatomic data on the left atrium and pulmonary veins, helping in transseptal punctures, locating the ostium and antrum of the pulmonary veins, monitoring tissue injury during radiofrequency (RF) use, preventing esophageal injury by monitoring the injuries caused by RF on the left atrial posterior wall and assessing the pulmonary vein flow.
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Usefulness of strain elastography of the musculoskeletal system

Usefulness of strain elastography of the musculoskeletal system

Ultrasound elastography is a widely used technique for assessing the mechanical characteristics of tissues. Although there are several ultrasound elastography techniques, strain elastography (SE) is currently the most widely used technique for visualizing an elastographic map in real time. Among its various indications, SE is especially useful in evaluating the musculoskeletal system. In this article, we review the SE techniques for clinical practice and describe the images produced by these techniques in the context of the musculoskeletal system. SE provides information about tissue stiffness and allows real-time visualization of the image; however, SE cannot completely replace gray-scale, color, or power Doppler ultrasonography. SE can increase diagnostic accuracy and may be useful for the follow-up of benign lesions.
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An Online Platform for Real-Time Sensor Data Collection, Visualization, and Sharing

An Online Platform for Real-Time Sensor Data Collection, Visualization, and Sharing

The web application provides time based charts, with four types of charts, line, bar, pie and radar charts. In every chart, is possible to add sensor variables to compare. As shown in Figure 27, we are representing the gas amount, temperature and human presence. For a better user interaction, we added a configuration panel, which provides basic chart options. Saving the chart as image, selecting the time interval of the chart (minutes, hour, day, week, month, year or years), the Y-axis minimum and maximum size, and offset to change the period of time, are some options of the chart panel.
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Real-Time Strategy Experience Exchanger Model Real-See

Real-Time Strategy Experience Exchanger Model Real-See

In this section we will try to summarize some case- based reasoning researches on real-time and/or strategy games. Some CBR researches has targeted real-time individual games, as Goodman’s (1994) [7] projective visualization for selecting combat actions, and predicting the next action of a human playing Space Invaders. MAYOR (1996) [6] used a causal model to learn how to reduce the frequency of failed plan executions in SimCity, a real-time city management game. Where Ulam et al.’s (2004) [17] meta-cognitive approach performs failure-driven plan adaptation for Freeciv game. They employed substantial domain knowledge, and addressed a gaming sub-task (i.e., defend a city). Molineaux and Ponsen (2005) [2] relax the assumption of a fixed adversary, and develop a case-based approach that learns to select which tactic to use at each state. They implemented this approach in the Case-based Tactician (CAT). They reported learning curves that demonstrate its performance quickly improves with training, even though the adversary is randomly chosen for each WARGUS game. CAT is the first case-based system designed to win against random opponents in a RTS game.
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An Extensible Real-time Visualization Pipeline for Dynamic Spatial Modeling

An Extensible Real-time Visualization Pipeline for Dynamic Spatial Modeling

Figure 4 depicts the class diagram of the monitoring mechanism and Figure 5 shows how the inter- actions between objects of these classes take place. A dirty-bit has been added to each element in the blackboard and to each observer. It indicates whether the internal state of the associated subject has changed, pointing out that such objects need to be updated to reflect the new state. Thus, when the simulation notifies the observers concerning changes in a subject, this notification only sets the dirty-bits to true. When an observer requests data about a dirty subject stored in the blackboard, the latter first updates itself, sets its dirty-bit to false, and then forwards the data to the observer. All other observers that need to be updated will find the data already decoded, updated, and stored in the blackboard. This way, a subject is serialized only once, even when there are many observers linked to it. After rendering the new subject state, an observer sets its dirty-bit to false to indicate that the visualization is updated.
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Crowdvis: a framework for real time crowd visualization

Crowdvis: a framework for real time crowd visualization

As explained in the related work chapter, the interactions among VHs can represent verbal or nonverbal communication, such as virtual humans checking their wristwatches, a simple “hello” gesture or even a conversation between two or more characters. In CrowdVis, the interactions are performed in “second plane”, without changing the simulation data. The main difference in comparison with our approach is that we provide a model to generate visual behaviors, which can be displayed as body animation or other any visual representation. But mainly, in our approach, the interaction behavior is generated without changing the simulation, treated as a post-processing analysis, since it is used for already simulated situations in our visualization. The main goal is to improve the realism and believability of the visualization (maintaining the simulation intact) and the techniques employed can also be used for other applications, such as games and any other suitable real time scenario.
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Nowcasting Brazilian GDP: a performance assessment of dynamic factor models

Nowcasting Brazilian GDP: a performance assessment of dynamic factor models

The literature that formalizes and treats this class of problems started approx- imately ten years ago with Evans (2005) and Giannone et al. (2008). The word nowcasting has been coined to name the problem of predicting the present, the recent past, or the near future. This term was already used in meteorology, and Gi- annone et al. (2008) incorporated it into economics for the first time. Although the literature about nowcasting is new, it emerged from another econometric literature branch on Dynamic Factor Models (DFMs). Some reasons for using these models in real-time forecasting are: they can handle a large number of variables in a joint structure, in a parsimoniously way; they do not discard information; they have good asymptotic properties.
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Experimental Determination of Cavitation Characteristics of Hydraulic Turbines

Experimental Determination of Cavitation Characteristics of Hydraulic Turbines

Hydraulic cavitation is a result of the state when water pressure drops below the critical pressure (generally vapor pressure) at constant temperature and vapor cavities are formed and grow based on the dynamic pressure reduction. These cavities stop to grow in a liquid flow when pressure rises again and they collapse and disappear. Implosion of the bubbles near solid surfaces causes surface erosion which damages the turbine. Cavitation types in hydraulic turbines can be classified as; travelling bubble, sheet, super, bubble ring, band, fixed patch, travelling patch, spot, cloud, tip vortex, vertical and shear flow cavitation. Travelling bubble, sheet, super, band, fixed patch, and spot types of cavitation are known as blade surface cavitation [12].
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Structural Analysis of Cavitation for Different Stainless Steels

Structural Analysis of Cavitation for Different Stainless Steels

Cavitation is caused by rapid vaporization and condensation of a liquid. It originates from voids or tiny bubbles containing gas and vapor which form a nucleus for vaporization.If these bubbles are subjected to vapor pressure, they grow rapidly. The collapse of the cavities causes noise, pressure fluctuations, vibrations, and possible erosion damage [4].

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Verifying Real-Time Systems using Explicit-time Description Methods

Verifying Real-Time Systems using Explicit-time Description Methods

On the other hand, Lamport [16] advocated the Explicit-Time Description Methods which aim to use ordinary model checkers to realize timed model checking. He presented an explicit-time description method using a clock-ticking process (Tick) to simulate the passage of time and a pair of global variables to store the time lower and upper bounds for each modeled system process. The main advantage of the explicit-time approach is that it does not need specialized languages or tools for time description. The method has been implemented with popular model checkers SPIN (sequential) [14] and SMV [17]. Re- cently, Van den Berg et al. [10] successfully applied LEDM to verify the safety of railway interlockings for one of Australia’s largest railway companies. The additional benefit of the explicit-time approach is that as it explicitly records the passage of time so the current time instant can be accessed easily, the pre-emptive scheduling problem discussed in the previous paragraph that causes difficulty using the timed-automata-based model checkers can be modeled naturally with explicit-time description methods. In this paper, we propose a new explicit-time description method called Sync-based Explicit-time Description Method (SEDM), which does not rely on global variables; instead it uses rendezvous syn- chronization steps between the Tick process and each system process. After the Tick process completes synchronization steps with every system processes, the global clock increments by one time unit. While, as Lamport commented [16], “The approach (LEDM) cannot be used in process-based languages and formalisms with no explicit global state, such as CCS, CSP, Petri nets, streams and I/O automata”, SEDM can do exactly that. As an added advantage, SEDM allows the timing constraints to be defined either globally or locally so the whole system can be modeled in a way that enhances its modularity. We choose D I V IN E [7], a well-known distributed model checker, because it accommodates the up-to-date multi-core architecture, i.e., clusters of multi-core CPU’s and it has been tested successfully in large-scale clusters, even in a large-scale optical grid [19]. Experimental results show that SEDM is comparable to LEDM with respect to time and memory efficiency so SEDM can be used in place of LEDM.
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Mat. Res.  vol.18 número6

Mat. Res. vol.18 número6

The assertion with regard to islands-like products nucleated at the nitrided surface is based on the 2D topography proile results presented in Figure 2. It is shown in Figure 2 that the number of peaks with amplitude between 0 and +600 nm at the nitrided surface was strongly increased in relation to the valleys (which ranged between 0 and –400 nm), comparatively to the non-nitrided surface. This is also conirmed by Table 1 results, which shows the average and standard deviation values of the 3D surface roughness parameters Sa, Sz, Sp, Sv, Sds, Ssk, and Sku. According to Table 1, Sa, Sz, Sp, Sv, and Sds values of the nitrided surface were increased of 5.2, 4.0, 6.5, 2.7, and 1.8 times in relation to non-nitrided surface, all these roughness parameters conirming the assertion regarded to the islands-like products nucleated at the nitrided surface, which make the surface roughness to be grown. Despite that the veriied roughness increment in the nitrided surface could be detrimental for cavitation erosion purposes, since it is very well established that roughness surface and cavitation resistance tend to be inversely correlated greatness, it is to be considered that the referred roughness increment is a self-result of the plasma nitriding process, and additional efforts to be conducted are necessary aiming to overcome this supposed problem.
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Comparison of real-time PCR and conventional PCR for detection of

Comparison of real-time PCR and conventional PCR for detection of

Abstract: In recent years, the polymerase chain reaction (PCR) technique has significantly advanced towards expanding its use and versatility by working with quantitative real-time PCR (qPCR). Data from the literature show that both methods present interesting characteristics for the diagnosis of visceral leishmaniasis. The benefits of qPCR in relation to conventional PCR include speed, reproducibility and quantitative ability. In addition to operational advantages, qPCR is more sensitive and reproducible and may replace conventional PCR in diagnostic routines. Regarding visceral leishmaniasis, the possibility of deployment of real-time PCR in highly complex diagnoses (reference services) in endemic areas will facilitate a swift and safe return for patients. Moreover, the use of a technique that possesses elevated diagnostic sensitivity, and can monitor therapy and prevent relapses promotes broader prospects for the disease control.
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Monitoring Architecture for Real Time Systems

Monitoring Architecture for Real Time Systems

ThreadX also has built-in system tracing capabilities, activated by enabling a single flag (EVENT_TRACE). If tracing is enabled ThreadX will store execution data in a circular buffer. The application can control the size, location and contents of the traces, and may also insert custom events through an API. To analyze and view this information Express Logic provides the TraceX tool [Logb]. Trace data is sent to an host machine after execution (off-line monitoring) or during execution when a breakpoint is hit. The circular buffer stores up to a certain number of recent events, making them available for inspection in the event of a system malfunction or an user defined breakpoint. The following events can be traced in both single and multi-core systems:
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Real-time 3D rendering of water using CUDA

Real-time 3D rendering of water using CUDA

Looking at Figs. 5.6 and 5.7, the reader may observe several details. The visual quality of both CPU and GPU-based Gauss-Seidel and Jacobi solvers is very similar. The Conjugate Gradient method, in both versions, gives slightly better water shaped effects than in the other two methods. However, the GPU-based version of Conjugate Gradient is only used on the diffusion of velocities and densities. Possibly due to floating point errors, the GPU- version does not give the correct results in the projection step. Therefore, instead of using the Conjugate Gradient, we use the Gauss-Seidel or Jacobi solvers in the projection step. The visual aspect of both the GPU and CPU-based versions differ mostly from the usage of different grid sizes. The rendering technique used for grid sizes smaller then 128x64x64 does not produce an uniform volume; consequently, we cannot distinguish the individual elements (i.e. we see the dots individually and not a continuous water volume). For a grid size of 128x64x64, the rendering technique resulted in a uniform water volume, where the individual water elements could not be distinguished from each other. However, none of the versions allowed such grid size because all water elements, and not only the water surface elements, were rendered. The reader will notice also that the textures of the GPU- based version look better. This results from the fact that the texture dimensions used are equivalent to the biggest grid dimension allowed. Therefore, the CPU-based version uses 32 × 32 textures, while the GPU-based version uses 64 × 64 textures. Another
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Codesign Methodology of Real-time Embedded Controllers for Electromechanical Systems

Codesign Methodology of Real-time Embedded Controllers for Electromechanical Systems

During architecture exploration the specification model is refined into an architecture model. This includes the following design steps: (i) allocation which determines the number and types of system components such as general-purpose or custom processors, memories and busses, which will be used to implement the system behavior; (ii) behavior partitioning which maps the behaviors (or processes) that comprise the system functionality onto the allocated processing elements; (iii) variable partitioning which assigns variables to memories; (iv) channel partitioning which assigns communication channels to busses; and (v) scheduling which determines the order of execution of the behaviors assigned to either the standard (software) or custom (hardware) processors after partitioning.
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Design and Implementation of Real Time Remote Supervisory System

Design and Implementation of Real Time Remote Supervisory System

It is NPN silicon planar phototransistor optically coupled to a gallium arsenide infrared emitting diode. Isolation circuit is used to provide isolation between input and output. It protect patient from shock. For checking the ECG signals on CRO we measure the ECG signals via CRO probes In most of the cases the Patient electrode ground and CRO ground is not the same, for such cases if the CRO ground is not properly earthed then the patient may get a Shock so for this reason we are interfacing a Opto- isolator which provides a optical insulation between the Electrode circuit and the Output circuit. [1].
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