Abstract The ice-cluster-based planar laser scattering technique, a high spatiotemporal resolution technique, is used to obtain the fine structures of dual-incident shock waves/turbulent boundary layer interaction. A double wedge produces these two incident shock waves. Three different interval distances between the incident shock waves are examined to obtain the influence of the second shock wave

Abstract Sampling techniques are widely used in the effort to reduce complexity and improve interpretability of datasets. Given the enormous availability of data, these techniques try to select representative data points that inherently reflect the data structure. In this work, we propose a novel sampling technique that preserves the structures imposed by dimensionality reduction techniques when visualized

Abstract Air pollution has become an important environmental issue, attracting more and more attention from many scholars and experts recently. Understanding air quality patterns in urban areas is essential for air pollution prevention and treatment. However, most existing studies usually cannot effectively capture air quality patterns from large-scale air quality data, due to lacking effective interaction

Abstract An appropriate location of the retailing store is vital for achieving business success. However, a massive amount of complex information needs to be considered in location selection, such as customer flow, the business environment, and current business performance. Unlike the traditional location recommendation method of statistical sampling, we establish a model of business-district attractiveness

Abstract We detect the trajectory of particles using the feature matching method to improve the resolution of particle streak velocimetry (PSV), which is used to measure the velocity of particles from a visualized path line. PSV has a more reliable performance in particle matching as compared to particle tracking velocimetry and is therefore less likely to cause erroneous matching even in high-density

Abstract Word cloud is a common text visualization technique. With the ability of presenting the keywords of a document in a direct way, it has been widely applied in many real-world situations. However, to better represent the main idea of a document, a critical aspect for word cloud design is to set an appropriate font size to facilitate semantic expression. In this paper, we explore the influence

Abstract Implementing particle image velocimetry (PIV) in particle-laden flows is a challenging task due to the optical effects of the added particles. The addition of particles reduces optical access in the measurement region, degrades image quality and increases the experimental uncertainty. One method for reducing this effect is by using refractive index matching (RIM) which matches the index of

Abstract The urban transportation system is the footstone of a city’s infrastructure, and the booming bike-sharing system has become a vital part of urban transportation. Understanding the bike-sharing system and traditional taxi system as well as their similarities and differences are essential for bike-sharing rebalancing, taxi dispatching, and urban planning. However, due to the sparseness of record

Abstract In recent years, subway has become an important transportation means for residents. Due to the huge passenger flow in metropolises, the urban metro network has become more and more complex. Some anomalies may have serious impact on the metro system and spread rapidly. Therefore, it is essential to find out the detail information of anomalies in the metro system. At the same time, mastering

Abstract Targeted advertising is a dominant form of online advertising. It considers advertisers’ major concern of their customers, including the consumers’ certain traits, interests and individual preferences. To promote the effectiveness of advertisement delivery, advertising analysts need to understand advertiser delivery behavior and problems in targeting structure. However, statistical methods

Flow transitions and vortical developments during vortex-ring collisions with a sharp water–oil density interface are studied using planar laser-induced fluorescence and time-resolved particle-image velocimetry techniques. Circular vortex-rings at Reynolds numbers of \(\hbox {Re}=1000, 2000\) and 4000 colliding with a density interface characterized by an Atwood number of approximately \(A=0.045\)

Abstract The flow visualization of a shock wave/boundary layer interaction (SWBLI) has been performed using polarization imaging. This technique used the degree of linear polarization (DOLP) for flow visualization instead of the intensity information which is used in traditional imaging methods. The experimental results show that the instantaneous structures of SWBLI captured by the polarization imaging

Abstract The phase-averaged skin-friction analysis based on global luminescent oil film (GLOF) was conducted for periodically fluctuating unsteady phenomena at the frequency of approximately 150 Hz which is estimated based on Karman vortex shedding. An unsteady pressure transducer and a camera were synchronized, and the time-averaged and phase-averaged skin-friction fields were investigated. The time-series

Abstract In this article, we describe a new feature for exploring eye movement data based on image-based clustering. To reach this goal, visual attention is taken into account to compute a list of thumbnail images from the presented stimulus. These thumbnails carry information about visual scanning strategies, but showing them just in a space-filling and unordered fashion does not support the detection

Abstract Internal serpentine ribbed coolant channel with low aspect ratio (AR) has been widely employed to provide excellent thermal protection for advanced first-stage turbine blades. Various height differences (ΔHs) of adjacent passages along pressure side can be generated under the restriction of actual blade profile. The present work made an attempt to acquire detailed influences of ΔH on the time-averaged

Abstract This paper presents the results of aluminum dust flame propagation inside a vertical prototype of 700 mm height and 150 × 150 mm square cross section. The study considers three visualization techniques. At first, direct visualization is employed to record the flame light with high speed camera. Special attention is given to collect images without saturation. This is especially important with

Abstract We present an experimental study on hydrodynamic cavitation generated by accelerating liquid through a series of constrictions in the presence of gas bubbles and explore its possible applications in water treatment with particular example in aquaculture industry. The formation of intense cavitation bubbles is visualized using a high-speed photography. The cavitation is initiated when a gas

Abstract This article discusses affordable schlieren methods which can visualize hidden details in three-dimensional high-speed flow. Mainly, two schlieren methods are brought to light, namely inclined schlieren and focusing schlieren. These two methods have been applied to visualize three-dimensional flow fields like normal shock boundary layer interaction in ducts and flows with shock–shock interactions

Abstract The growing number of students can be a challenge for teaching visualization lectures, supervision, evaluation, and grading. Moreover, designing visualization courses by matching the different experiences and skills of the students is a major goal in order to find a common solvable task for all of them. Particularly, the given task is important to follow a common project goal, to collaborate

Abstract Researchers have a great interest in determining the characteristics of shock wave propagation by an underwater explosion. But it involves complex physical processes near boundaries during the underwater explosion. The major issues are explosions, fluid interactions, fluid–structure interactions, and shock wave propagation. In general, the underwater explosion leads to shock wave propagation

Abstract Time-varying volume data is often generated from scientific simulations in a variety of application domains, such as computational fluid dynamics, combustion science, and computational cosmology. Data visualization plays an important role in analyzing the dynamics and evolution of phenomena hidden in the data. Over the last two decades, a substantial amount of visualization techniques have

Abstract The paper is devoted to the processing and analysis of the high-speed visualization data on water pool boiling in the pressure range of 5.5–103 kPa. The study of the vapor bubbles dynamics and evolution of void fraction near a heated wall during boiling was performed using a special design of a transparent heating element and high-speed visualization from its bottom side. To analyze the wide

Abstract We report on the state-of-the-art of software visualization. To ensure reproducibility, we adopted the Systematic Literature Review methodology. That is, we analyzed 1440 entries from IEEE Xplore and ACM Digital Library databases. We selected 105 relevant full papers published in 2013–2019, which we classified based on the aspect of the software system that is supported (i.e., structure, behavior

Abstract This paper proposes a method to identify low-pressure vortices with swirling motions around a vehicle by considering the two-dimensional pressure minimum. The existing sectional-pressure-minimum-and-swirl method combined with the finite difference method can be used to identify low-pressure vortices with swirling motions in homogeneous isotropic turbulence. To apply this method to the flow

Mathematical knots are different from everyday ropes, in that they are infinitely stretchy and flexible when being deformed into their ambient isotopic. For this reason, challenges of visualization and computation arise when communicating mathematical knot’s static and changing structures during its topological deformation. In this paper, we focus on visual and computational methods to facilitate the

Abstract A global luminescent oil-film (GLOF) image analysis method to estimate unsteady skin-friction fields in an unsteady flow field is proposed and demonstrated. A governing equation describing the dynamics of the oil film (the thin-oil-film equation) is employed for the unsteady oil-film images. The frequency response of the oil-film movement is analyzed, and a cutoff frequency is defined as a

Abstract An in situ visualization system based on the particle-based volume rendering offers a highly scalable and flexible visual analytics environment based on multivariate volume rendering. Although it showed excellent computational performance on the conventional CPU platforms, accelerated computation on the latest many core platforms revealed performance bottlenecks related to a function parser

Abstract A method to determine the depth of detection (DOD) for particle shadow tracking velocimetry (PSTV) is presented. In contrast with other image-based velocimetry techniques, PSTV is capable of measuring particle velocity in a volume of the flow. However, a precise methodology to determine the size of the measurement volume was not available (in particular, for internal flows in tubes with circular

Abstract Airfoils are mostly inefficient in their off-design conditions. In order to improve the aerodynamic performance of airfoils in these conditions, using an optimized cavity on airfoils as a passive method can be useful. In this study, a cavity on a Risø_B1_18 airfoil, which is used as a wind turbine airfoil, was optimized at an off-design angle of attack by incorporating a genetic algorithm

Abstract The analysis of molecular cavities, which are transport pathways in protein structures, is critical to the understanding of molecular phenomena. However, this work is challenging due to the high complexity and diversity of the macromolecular shapes in dynamic processes. In this paper, we propose a novel multiscale visualization method for visualizing the interaction of protein cavities. We

Abstract Noise from jet engines can be reduced by means of a Helmholtz cavity configuration. The resonance that occurs when a flow passes the neck of the Helmholtz resonator will dissipate acoustic energy. The mechanism for such dissipation is mainly due to the vortex shedding that occurs at the neck of the resonator where the vortex structures absorb acoustic energy and subsequently dissipate it through

Abstract Flow dynamics of two-dimensional liquid sheets discharged into low-speed gaseous crossflow were experimentally investigated. The flow characteristics of liquid sheets were visualized by taking advantage of diffused backlight shadowgraphy and high-speed photography. Three injectors with an equal thickness of 0.35 mm and aspect ratios of 30, 60 and 90 were manufactured and tested at different

Abstract  To enrich the three-dimensional experimental details of vortex structures in rotating Rayleigh–Bénard convection, we established a technique visualizing three-dimensional vortex structures using scanning planar particle image velocimetry. Experiments were performed at fixed Rayleigh number, \(\hbox {Ra} = 1.0 \times 10^7\) and different Taylor numbers from \(\hbox {Ta} = 6.0 \times 10^6\)

Abstract Nuclear magnetic resonance images have been used for detecting the movement of water molecules in living organisms and moreover exploiting the neural fibers distribution, which is of great significance for the brain disease analysis. However, due to the visual clutter of dense fiber tracts, it is difficult for medical researchers to understand the water molecule diffusion in whole-brain scale

Abstract The interactions of the bubbles in a loosely packed bubbly flow in a high viscous fluid approaching a pore space are studied using a shadowgraph imaging technique. The motion of the bubbles has been evaluated by considering shape analysis of their deformation and the variation in the velocity and pressure distribution of the phase. A comparison of two cases of a linear array and a matrix of

Abstract We carry out experiments on vortex ring flows submerged underwater which are generated by a pulsatile circular jet with the stroke ratio of 10. The pulsatile Reynolds number, based on centerline exit velocity and jet diameter, is a cosinusoidal function of time with a mean part of 2000 and an oscillating part of 820. This axisymmetric flow field is measured in a meridian symmetry plane by

Abstract Schlieren visualization of the plume ejected from the microgas turbine nozzle was conducted to understand infrared signal characteristics of various shapes of the exhaust nozzle. At the same time, the precise temperature distribution and infrared signal measurement were performed and compared. The maximum thrust of the microgas turbine used in the experiment is 230 N, the maximum speed of

Abstract Higher-order information of moving objects is of great importance for processing in-case scenarios in emergency management. Multivariate higher-order information management is a crucial key to the success of emergency management since emergency management involves developing plans with a given set of multiple resources. Past studies focus on univariate higher-order information limiting the

We present a series of three-dimensional visualizations of numerically simulated turbulent wakes in a stably stratified fluid with a focus on the effects of the wake Reynolds number, Re, on the wake flow. The visualization of stratified wakes is complicated by the coexistence of regions of distinct dynamics in the flow, including large-scale ‘pancake vortices,’ small-scale shear instabilities within

This paper is a comparative study on the characteristics of high-speed liquid jets injected in surrounding water and air using shadowgraph technique. One of the main objectives is to investigate the effects of liquid’s physical properties, used to generate the high-speed liquid jets, on jet generation’s characteristics. Moreover, comparative investigations on effects of those liquid jets after injected

Graphic abstract

Graphic abstract

Abstract In the field of evolutionary genome analysis, biologists seek to identify important genes or chromosome regions by comparing phylogenetic trees and analyzing the mutation at which locus might affect phenotypic traits. Unfortunately, the tree comparison and accompanying analysis are often performed manually. In this paper, we characterize the workflow of evolutionary genome analysis and present

Graphic abstract

Abstract In this study, the visualization of the flow inside a Taylor cone formed during an electrohydrodynamic (EHD) spraying is conducted to analyze its stability among five liquid candidates. A micro-PIV with a micro-nozzle is used for the visualization, and the physical properties as well as measured values are utilized in the analysis. First, in forming the Taylor cone, the electrohydrodynamic

Abstract Journalists, government agency and the public may hold different opinions about the same event; these opinions flow within and across multiple social groups. Understanding opinion flow in multiple social groups is conducive to have a quick grasp of the information on social media. Our study aims to explore the opinion flow within or across the pre-defined social groups and the mutual influence

Abstract The in-cylinder flow prior to combustion is considered to be one of the most important aspects controlling the combustion process in an engine. More specifically, the large-scale structures present in the cylinder, so-called tumble and swirl, before compression are believed to play a major role into the mixing and combustion processes. Their development during the intake stroke and their final

Abstract Since the abstract can be found at the beginning of most scientific articles and is an essential part of the article, several attempts have been made to explore the rhetorical moves of abstracts in various research fields. These studies dealt only with accepted articles since they can be easily accessed. Although the findings of such works have some pedagogical implications for academic writing

Abstract Magnetic resonance elastography (MRE) is a technique to identify the viscoelastic moduli of biological tissues by solving the inverse problem from the displacement field of viscoelastic wave propagation in a tissue measured by MRI. Because finite element analysis (FEA) of MRE evaluates not only the viscoelastic model for a tissue but also the efficiency of the inversion algorithm, we developed

Abstract During the ground operation of aircraft, the interaction between the propulsor-induced flow field and the ground may lead to the generation of ground vortices. Utilizing numerical approaches, the source of vorticity entering ground vortices is investigated. The results show that the production of wall-parallel components of vorticity has a strong contribution from the wall-parallel components

Abstract The interaction between a propeller and its self-induced vortices originating on the ground is investigated in a scaled experiment. The velocity distribution in the flow field in two different planes containing the self-induced vortices is measured by particle image velocimetry (PIV). These planes are a wall-parallel plane in close proximity to the ground and a wall-normal plane just upstream

ABSTRACT In this study, the effect of cutting the end of a thick airfoil and adding a cavity on its flow pattern is studied experimentally using PIV technique. First, by cutting 30% chord length of the Riso airfoil, a thick blunt trialing-edge airfoil is generated. The velocity field around the original airfoil and the new airfoil is measured by PIV technique and compared with each other. Then, adding

ABSTRACT A novel method, called a posteriori "VFM accuracy estimation" (VAE), for resolving an intrinsic VFM problem is proposed. The problem is that VFM uncertainty can easily vary according to blood flows through an echocardiographic imaged plane (i.e., "through-plane" flows), and it is unknown. Knowing the VFM uncertainty for each patient will make it possible to refine the quality of VFM-based

ABSTRACT A series of experiments involving the particle image velocimetry technique are carried out to analyse the quantitative effectiveness of the synthesized vortical structures towards actual flow separation control. The streamwise vortices are synthesized from the synthetic jet actuator and introduced into the attached and separating boundary layer developed on the flat plate surface. Two types

ABSTRACT An experimental study has been conducted to visualise the instantaneous streamwise and spanwise flow patterns of a normal shock wave impinging over a rounded contour bump in a Mach 1.3 free-stream. A quartz-made transparent shock generator was used, so that instantaneous images could be captured during the oil-flow visualisation experiments. Fluorescent oil with three different colours was

ABSTRACT The instability analysis of the liquid jet issuing into ambient air was conducted with an emphasis placed upon the evolution of surface waves of the jet. An experiment was designed to visualize the microscopic morphology on the surface of a liquid jet. A spectral method was proposed to measure wavelength from the obtained jet images. We also discuss key setup parameters that significantly

ABSTRACT An iterative back projection method (i-BP) has been developed to improve the resolution of reconstructed images produced by electrical resistance tomography (ERT). This solution is based on an iterative calculation of the electrical fields and it is possible to reconstruct clearer images than those reconstructed by the conventional back projection method without divergence. However, it does

ABSTRACT A low-density wind tunnel called the Mars wind tunnel, has been developed at Tohoku University that can produce a high subsonic flow at low pressures for aerodynamic measurements of low-Reynolds-number aircraft wings aimed at developing aircraft applicable to the atmosphere on the planet Mars. Accurate surface pressure measurements on the wing are essential for analysis of not only aerodynamic

This study was performed to determine the relations between the features of wall shear stress and aneurysm rupture. For this purpose, visual data mining was performed in unsteady blood flow simulation data for an aortic aneurysm. The time-series data of wall shear stress given at each grid point were converted to spatial and temporal indices, and the grid points were sorted using a self-organizing