Direct Volume Research Articles

Urban road traffic noise on human exposure assessment using geospatial technology

The sounds produced by humans, industries, transport and animals in the atmosphere that pose a threat to the health of humans or animals can be characterized as noise pollution. Adverse effects due to noise exposure can involve speech communication interference and declining learning skills of children. Highway traffic noise contributes to 80% of all noise. It has grown to a massive scale because of growth in population along the roads leading to a rapid change in land use and has evolved into a common reality in various Indian cities. The main objective of this work is to develop a road traffic noise prediction model using ArcGIS 10.3 for the busy corridors of Chennai. The collected data includes traffic volume, speed, and noise level in lateral and vertical directions. Noise levels were measured in 9 locations using a noise level meter. It is observed that the noise levels vary from 50 dB to 96 dB. It is found that the noise problem is severe in 18% of the area, and 6.3% of people are exposed to the traffic noise problem. The results obtained in this study show that the city is affected by severe noise pollution due to road traffic.

Polypropylene‐based soft ternary blends for power cable insulation at low‐to‐high temperature

AbstractAlthough cross‐linked polyethylene (XLPE) has been widely used as a power cable insulation material in electricity infrastructure for decades, it is necessary to find alternatives that exhibit higher performance than XLPE to meet the increasing demand of the industry. To this end, polypropylene (PP) ternary blends that are soft and exhibit high temperature stability were fabricated by melt blending isotactic PP, ethylene‐1‐octene polyolefin elastomer and ethylene‐propylene random copolymer. These blends exhibited improved higher impact resistance at low temperatures (−40°C) and room temperature than pristine iPP. The blends were mechanically stable even when the temperature was increased to ~120°C, unlike XLPE that exhibited rapid degradation of its modulus above ~90°C. Moreover, the soft ternary blends exhibited increased direct current volume resistivity and breakdown strength. Our work realizes the development of high‐performance insulators for power cables that can be used over a wide range of temperatures from cold to hot environments.

An Adaptive Neural Fuzzy Inference System model for freeway travel time estimation based on existing detector facilities

While volume-counting detectors are currently installed in many freeways and have the capabilities of collecting high-resolution traffic information, travel time estimations are usually only based on spot speeds collected by the detectors, which could only produce rough estimates of travel time during peak hours when roadways are congested. In addition to spot speeds, these detectors provide directional volume counts and occupancy, which are useful for a better travel time estimation. This research used data from volume counting detectors and made Adaptive Neural Fuzzy Inference System (ANFIS) to automatically estimate real-time travel times. ANFIS’s ability to learn traffic patterns allows accurate and reliable real-time travel time estimation even with missing or corrupted data. ANFIS also proves to be a powerful tool for estimating future travel times on freeways. For easier use by practitioners and researchers, the method used in this study was implemented into a software package, named FTTE (Freeway Travel Time Estimator). Finally, a case study was conducted using the new approach and the results were compared for both congested and uncongested traffic conditions.

Quantitative three-dimensional image analysis of the superior canal after surgical plugging to treat superior semicircular canal dehiscence

Surgical plugging to treat superior semicircular canal dehiscence (SCD) has been proven to impede the effect of the third mobile window, abating cochleovestibular symptoms. Knowledge of superior semicircular canal (SC)-plugging status has been proposed to serve as a guide for adjuvant treatment. Here, we investigated disturbances in the inner ear fluid space following SC plugging using a novel three-dimensional (3D) reconstruction-based method. This approach used a semi-automatic segmentation algorithm and a direct volume rendering method derived from conventional magnetic resonance images. The variable extents of filling defects at the sites of SC plugging and the positional relation of the defect to the ampulla and common crus were identified. The success group exhibited markedly reduced volumes following surgery, whereas the failure group displayed no changes in volume. These results indicate that the success or failure of SC plugging was related to 3D volume changes in the labyrinth fluid signal. Collectively, this study presents individualized SC-plugging statuses using a novel 3D reconstruction-based method and it facilitates future work regarding easy-to-measure 3D volume changes. This current technology also aids in the exploration of pathologic changes in various targets of interest.

Brief design and numerical calculations for a secondary road

Based on the traffic volume survey, the standard traffic volume conversion is considered, and then the road traffic volume is predicted. Through the calculation, the maximum annual average daily traffic volume in the design life is obtained, and then the road grade and design speed of the design road are determined. The Annual Average Daily Traffic (AADT) is converted into Directional Design-Hour Volume (DDHV), and then the number of lanes of the road is determined. Collect the terrain data of the route area through the field survey, and then carry on the interior design. The route schemes are compared and the optimal route scheme is selected. AUTOCAD and a professional road design software were used to assist in the design of road line selection, horizontal curve design, vertical section design, cross section design and drainage design. Through the calculation, the design parameters such as the maximum synthetic slope, the average slope and the minimum length of superelevation transition section are obtained. Afterwards, the parameters in horizontal curve, vertical curve and superelevation-widening were checked manually.

Dynamics of a buoyant pulsating bubble near two crossed walls

The dynamics of a buoyant pulsating bubble near two crossed perpendicular rigid boundaries (a horizontal and a vertical wall) are studied using the boundary element method combined with the method of mirror images. The Kelvin impulse and the elastic mesh velocity method are used to calculate the direction and volume of the liquid jet generated during bubble collapse. The numerical results show good agreement with experiments. An increase in buoyancy causes a local high-pressure zone at the root of the jet to move toward the bottom of the bubble, causing the jet to rotate upward toward the vertical wall. At a certain position, with the change in buoyancy, the dimensionless bubble volume at the instant of jet impact reaches a minimum when the jet direction is horizontal, with a peak in the dimensionless jet velocity occurring. A comprehensive parametric study of jet characteristics, including jet direction, velocity, and relative volume (the volume ratio of the jet to the bubble at the instant of jet impact), is carried out in terms of buoyancy and the standoff distances to the two walls. The Blake criterion can be used to judge whether a bubble jet is pointing obliquely upward or downward, provided that it deviates significantly from the horizontal direction. Depending on the buoyancy, the jet characteristics at different standoff distances are found to exhibit three distinct patterns of behavior. Finally, we discuss the changes in the jet velocity and relative volume as the buoyancy is varied.

Anesthetic Management of A Giant Abdominal Aneurysm Monitored with The Flo-TracTM/Vigileo System

Background: The Flo-TracTM/Vigileo system (Edwards Lifesciences, Irvine, CA, USA) can be used to estimate cardiac output and stroke volume variation for giant abdominal aortic aneurysm (AAA). Case Presentation: A 60-year-old male patient presented with a thrombosed abdominal aortic aneurysm approximately 8.8 x 8.4 cm in size. The patient was scheduled to undergo open repair. The left radial artery was punctured to monitor direct arterial pressure, stroke volume, cardiac output, and SVV. A Flo-TracTM sensor (Edwards Lifesciences, Irvine, CA, USA) was connected to the arterial monitor system. The aneurysm was opened and longitudinally incised. A total of 600 ml of blood in the aneurysm was drained, and mural thrombi were removed. The graft was proximally anastomosed to the pararenal abdominal aorta. The distal potion of the graft was anastomosed to the iliac bifurcation. The clamping time was 62 min. The CO and SVV measured by the Flo-TracTM sensor were 4.2 L/min and 8%, respectively. Conclusions: We report a case of giant AAA where intravascular volume control was obtained by CO and SVV, which were monitored by a Flo-TracTM/Vigileo system.

Approximate Image-Space Multidirectional Occlusion Shading Model for Direct Volume Rendering

Understanding and perceiving three-dimensional scientific visualizations, such as volume rendering, benefit from visual cues produced by the shading models. The conventional approaches are local shading models since they are computationally inexpensive and straightforward to implement. However, the local shading models do not always provide proper visual cues since non-local information is not sufficiently taken into account for the shading. Global illumination models achieve better visual cues, but they are often computationally expensive. It has been shown that alternative illumination models, such as ambient occlusion, multidirectional shading, and shadows, provide decent perceptual cues. Although these models improve upon local shading models, they still require expensive preprocessing, extra GPU memory, and a high computational cost, which cause a lack of interactivity during the transfer function manipulations and light position changes. In this paper, we proposed an approximate image-space multidirectional occlusion shading model for the volume rendering. Our model was computationally less expensive compared to the global illumination models and did not require preprocessing. Moreover, interactive transfer function manipulations and light position changes were achievable. Our model simulated a wide range of shading behaviors, such as ambient occlusion and soft and hard shadows, and can be effortlessly applied to existing rendering systems such as direct volume rendering. We showed that the suggested model enhanced the visual cues with modest computational costs.

Design and Development of an Embedded Controller for a Hydraulic Walking Robot WLBOT

In order to meet the requirement for the real-time of the hydraulic walking robot (WLBOT) and the stability of its movement, an embedded controller is proposed, which takes charge of multi-sensor information processing and signal output of the servo valve. The controller is capable of receiving control command and sending processed information while communicating with an embedded single board computer PCM-3365 via Control Area Network (CAN) bus at a 200 Hz frequency. In this paper, an appropriate interrupt cycle is selected and a 2 kHz high-speed control loop is run after we research the relationship between analog-to-digital converter direct memory access (ADC–DMA) interrupt cycle, data volume, and sampling rate. Significantly, the control strategy of WLBOT joint is introduced and a proportional-integral-derivative (PID) compound controller with velocity feedforward compensation (VFC) is realized. Meanwhile, the Chebyshev filtering algorithm is utilized to attenuate the vibration noise of joint signals. What’s more, an impedance controller is designed to gain better locomotion behavior and compliance in joint force control. Finally, the joint angle tracking and robot walking experiments are implemented, where the feasibility of the design and the validity of the control algorithm is verified. The results show that the PID velocity feedforward compensation controller can reduce the maximum tracking error by 39.13% and 71.31% in the knee and hip joint and the impedance control can reduce the standard deviation (SD) of the foot force by 36.06% and 72.79%.

Analytical Solutions for Transversely Isotropic Fiber Reinforced Composite Cylinders Under Internal or External Pressure

This paper deals with the elastic stresses of internally or externally pressurized long thick-walled composite cylinders with fixed ends. Cylinders are made of unidirectionally aligned transversely isotropic fibers and isotropic matrix. Axial and radial fiber alignments are considered, and analytical solutions are derived accordingly. Effects of fiber direction and fiber volume fraction alteration on the elastic limit stresses are analyzed. It is observed for both internal and external pressure cases that fiber direction and fiber volume fraction are important parameters which impact the elastic behavior of the cylinders.

Evaluating surface visualization methods in semi-transparent volume rendering in virtual reality

ABSTRACT Perceptual visualisation of semi-transparent structures in volumetric datasets is challenging due to its inherent visual complexity. This is however of primary importance in medical visualisation where raymarching of volumetric data is common. While rendering volumetric data itself is a well-explored area, perception of volume-rendered images combined with semi-transparent mesh data remains an underexplored topic. As virtual reality (VR) is increasingly employed for medical data inspection, it becomes important to understand how different mesh visualisations affect performance in medical tasks in this context. When considering direct volume rendering in immersive VR, the effects of stereoscopic vision and motion parallax require additional consideration. We investigate how surface transparency modes affect task performance in VR. For two medical image analysis tasks, we conduct a user study (n = 23) to analyse the impact of mesh rendering methods on task outcome and subjective preference. Our evaluation indicates that user performance with wireframe rendering varies greatly between tasks while constant opacity and silhouette provide a stable benefit. Overall, transparent visualisations led to improved precision (lower error rate, lower inter-observer variability) and increased user confidence, while the efficiency of visualisation methods was task-dependent. This demonstrates how semi-transparent rendering will improve visual analysis in medical applications and other disciplines.

Anisotropic defect distribution in He+-irradiated 4H-SiC: Effect of stress on defect distribution

Irradiation-induced anisotropic swelling in hexagonal α-SiC is known to degrade the mechanical properties of SiC; however, the associated physical mechanism and microstructural process remain insufficiently understood. In this study, an anisotropic swelling condition where the surface normal direction was allowed to freely expand with constraint in the lateral direction was introduced in 4H-SiC using selected-area He+ irradiation, and the internal defect distribution was investigated using transmission electron microscopy (TEM) and advanced scanning TEM. The defect distribution was compared to that in non-selected-area He+-irradiated 4H-SiC and electron-irradiated TEM-foil 4H-SiC. An anisotropic defect distribution was observed in the selected-area He+-ion-irradiated 4H-SiC, with interstitial defects preferentially redistributed in the surface normal direction ([0004]) and negative volume defects (such as vacancies and/or carbon antisite defects) dominantly located in the lateral directions ([112¯0] and [101¯0]). This anisotropy of the defect distribution was substantially lower in the non-selected-area He+-irradiated and electron-irradiated samples. The stress condition in the three samples was also measured and analyzed. In the selected-area He+-irradiated 4H-SiC, compressive stress was introduced in the lateral directions (([101¯0] and [112¯0])), with little stress introduced in the surface normal direction ([0004]); this stress condition was introduced at the beginning of ion irradiation. The compressive stress likely inhibits the formation of interstitial defects in the lateral directions, enhancing the anisotropy of the defect distribution in SiC.

Dielectric, magnetic and structural properties of Co-doped hexaferrite synthesized by microwave digestion system

Co substitution in hexaferrites Sr1−xCoxFe12O19 compounds with doping values x = 0.0, 0.075, 0.15, 0.225 and 0.30 were prepared using microwave digestion system. Structural, morphological, magnetic and dialectic properties were investigated. X-ray diffraction pattern proved a hexagonal phase (SrFe12O19) existing as a main phase for all samples. The lattice parameters, crystallites size and other parameters such as microstrain and direct cell volume and dislocation density were calculated from the Rietveld refinement of the X-ray results. The SEM and TEM results confirmed a hexagonal structure existing. The histogram of the particle size distribution showed variation of the grain size with nano range between 90 nm and 178 nm. Magnetic results showed that the magnetization (M), saturation magnetization (Ms), and remnant magnetization (Mr) increased with increasing of Co substitution while the coercive magnetic field, Hc, fluctuated with increase of Co substitution because of the irregular change of the grain size of the samples. The sample x = 0.15 has a low coercive field because of the uniformity of the crystal grains. Such magnetic properties recommend this sample to be used in magnetic applications. The dielectric study of these samples revealed that the AC conductivity, σ, increases with increasing the frequency while impedance (Z), dielectric constant (ε), dielectric loss, and tan δ decrease exponentially with F(Hz). The dissipation factor was found to have a convert frequency point at low F(Hz) after its starting to decrease slowly to the end of F-range. These dielectric properties suggest the validity of these hexaferrites compounds to be used as a capacitor.

Impacts of elasticity and porosity of the channels on the performance features of thermoelectric module mounted system and efficient computations with multi-proper orthogonal decomposition approach

Effects of wall elasticity and porosity of the channel on the performance characteristics of TEG module integrated system are explored numerically with finite element method. A porous layer in the lower channel is introduced with hybrid nanoparticles in the fluid. Effects of different values of elastic modulus of the top and bottom channel walls (5×103≤E1,E2≤1010), Darcy number (5×10−4≤ Da ≤5×10−1), porous layer height (0.2H ≤ py ≤ 0.8H) and length in flow direction (0.25L ≤ px ≤ 0.85L), Reynolds number (200 ≤ Re ≤ 1000) and hybrid nanoparticle volume fraction (0 ≤ϕ≤ 2%) on the convection and power generation are analyzed. The presence of elastic walls may affect the flow field in local regions but the overall impact on the power variation is slight while 2.8% variation is obtained. The presence of the porous layer altered the power generation features while increasing the permeability and height of the porous layer resulted in higher thermoelectric power generation. The increment amounts are 32% for the highest permeability and 17% for the highest porous layer height. The length of porous layer in the flow direction has slight impact on power generation features while introducing nano-sized particles further enhanced the power by about 15% at the highest ϕ. The computational cost of generated power is drastically reduced from 2.5 h for full coupled model to two minutes by using a multi-POD approach.

Impact of agricultural land-use change to the surface run-off: a case study of Cereng catchment area, Kulon Progo Regency, Special Region of Yogyakarta

Agricultural land-use changes can cause a reduction in the green open space area, thereby reducing infiltration and increase surface run-off. One of the phenomena in agricultural land-use changes as indicated by the addition of the percentage of irrigation paddy fields in Cereng Catchment Area (CA) by 2.31%, 2.94%, and 4.39%, respectively, in 1995, 2008, and 2018. Besides, the addition of the settlement area and the plantation area’s reduction were also phenomena of land-use change. The impact of these changes is associated with curve number (CN) and direct run-off. The analysis conducted on the relationship between effective design rainfall and response to the land-use changes to produce direct run-off volume in 2, 5, 10, 20, and 50 years-return period, respectively, in 1995, 2008, and 2018 using the HEC-HMS model. The result showed that have addition to CN that were 81.85, 85.82, and 86.66, respectively, in 1995, 2008, and 2018. This addition caused an increase in the percentage of direct run-off volume from 1995 to 2018; those values were 24.28%, 16.8%, 13.76%, 11.61%, and 9.53%, respectively, at the 2, 5, 10, 20, and 50-years return period. The increase in the value of direct run-off volume causes a high possibility of a flood.

Express Methods and Procedures for Determination of the Main Egg Quality Indicators

The article considers the methods, procedures and results of experimental studies of the main egg quality indicators. The offered express methods and the automated installation provide definition of the weight, the form and density of egg. Based on the results of experimental studies of egg parameters, the express method of determining the volume of the egg through the area of the longitudinal section and the small diameter of the egg is substantiated. The express method for density determination by direct mass measurement and volume calculation gives minimal absolute error and provides a six time increase in performance, compared to the direct method.

Abstract PS9-35: Volumetric assessment of lymphedema with 3D sensor

Abstract Volumetric assessment of lymphedema with 3D sensor: A new practical method Secondary lymphedema of the upper extremities is an important quality-of-life issue for around 40% of patients who were treated for breast cancer and required axillary nodal dissection and radiotherapy. Volume measurement is an important aspect of diagnosis, follow up, and evaluation after conservative or surgical treatment for lymphedema. Until now, there have been complex techniques to assess volume of affected limbs: bioimpedance, liquid-displacement volumetry, CT, MRI. There is a need for a practical method of volumen assessment in lymphedema patients. The objective of the present study is to confirm whether or not 3D scanning for volumetric assessment is useful and correlates with direct perimeter measurement and indirect volume calculation. Methods: A 3D sensor (Structure Sensor, Occipital Inc) mounted on an Ipad (Apple, Inc.) was used to make a 3D model file of the affected limb, that was later analyzed by 3DsizeME software (TechMed 3D, Inc.) in a desktop computer. 3D model analysis allows to measure perimeters and volumes. Fifteen patients were measured, lymphedema and normal limbs (30 extremities) by this technique and were also measured with tape, as traditional method; results were compared to assess correlation. Results: There were not statistical difference between the two techniques (p 0.05). Table attached. Discussion: volumetric assessment by 3D sensor allows consistent and reproducible measurements. It is practical as we only need the space of an ipad, it can be performed in the clinic visit, by any doctor, nurse or physical therapist. It is not expensive, as the software charges US$10 by each analysis. It do not expose the patient to any harmful radiation, as is obtained by and infrared camera. Allows electronic records of all measurements. Average time to capture 3D model is 5 minutes. We think this new method is a valuable tool for any lymphedema clinic as volume measurement is important for disease evaluation and now, more important, with a growing field of surgical treatment for this disease. Citation Format: Alejandro Maciel-Miranda, Miriam I Otero-Hernández, Darinka Martínez-Silva, Jesus F Escrivá-Machado. Volumetric assessment of lymphedema with 3D sensor [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS9-35.

Analysis of the effect of directional traffic volume and mix on road traffic crashes at three-legged unsignalized intersections

Traffic volume is the most common factor associated with road traffic crash frequency. Use of aggregate volume measures may lead to biased prediction of crash frequencies. Disaggregate analysis that involve hourly volumes can better explain this effect. In low and middle-income countries traffic mix may vary with respect to direction of travel on a road and such variation in proportion leads to crashes and conflicts among crossing vehicles at unsignalized intersections. This paper aims to explore the above relationship in the context of three-leg unsignalized intersections in Malaysia. First exploratory analysis of geometric and traffic variables was performed and their relationship with the crash frequency and type of conflicts was examined. Then probability of crashes was calculated with respect to the percentage of motorcycles that moved in a certain direction and proportion between volume in each direction. Segregation of the data with respect to traffic direction and traffic mix indicated that sites with less percentage of motorcycles moving in the far side direction experienced more crashes as compared to sites with greater percentage of motorcycles moving in the far side direction, given the condition that the volume ratio between each direction was larger than one. Results showed that the chances of crashes and serious conflicts increased upto 25% and 67% respectively; as the percentage of motorcycles that moved in the far side direction decreased from 31%, subject to the condition that the ratio of volume between each direction remained greater than one. It was concluded that traffic mix and traffic volume together influence the crash frequency at unsignalized intersections.

VC-Net: Deep Volume-Composition Networks for Segmentation and Visualization of Highly Sparse and Noisy Image Data.

The fundamental motivation of the proposed work is to present a new visualization-guided computing paradigm to combine direct 3D volume processing and volume rendered clues for effective 3D exploration. For example, extracting and visualizing microstructures in-vivo have been a long-standing challenging problem. However, due to the high sparseness and noisiness in cerebrovasculature data as well as highly complex geometry and topology variations of micro vessels, it is still extremely challenging to extract the complete 3D vessel structure and visualize it in 3D with high fidelity. In this paper, we present an end-to-end deep learning method, VC-Net, for robust extraction of 3D microvascular structure through embedding the image composition, generated by maximum intensity projection (MIP), into the 3D volumetric image learning process to enhance the overall performance. The core novelty is to automatically leverage the volume visualization technique (e.g., MIP - a volume rendering scheme for 3D volume images) to enhance the 3D data exploration at the deep learning level. The MIP embedding features can enhance the local vessel signal (through canceling out the noise) and adapt to the geometric variability and scalability of vessels, which is of great importance in microvascular tracking. A multi-stream convolutional neural network (CNN) framework is proposed to effectively learn the 3D volume and 2D MIP feature vectors, respectively, and then explore their inter-dependencies in a joint volume-composition embedding space by unprojecting the 2D feature vectors into the 3D volume embedding space. It is noted that the proposed framework can better capture the small/micro vessels and improve the vessel connectivity. To our knowledge, this is the first time that a deep learning framework is proposed to construct a joint convolutional embedding space, where the computed vessel probabilities from volume rendering based 2D projection and 3D volume can be explored and integrated synergistically. Experimental results are evaluated and compared with the traditional 3D vessel segmentation methods and the state-of-the-art in deep learning, by using extensive public and real patient (micro- )cerebrovascular image datasets. The application of this accurate segmentation and visualization of sparse and complicated 3D microvascular structure facilitated by our method demonstrates the potential in a powerful MR arteriogram and venogram diagnosis of vascular disease.

Deep Volumetric Ambient Occlusion

We present a novel deep learning based technique for volumetric ambient occlusion in the context of direct volume rendering. Our proposed Deep Volumetric Ambient Occlusion (DVAO) approach can predict per-voxel ambient occlusion in volumetric data sets, while considering global information provided through the transfer function. The proposed neural network only needs to be executed upon change of this global information, and thus supports real-time volume interaction. Accordingly, we demonstrate DVAOs ability to predict volumetric ambient occlusion, such that it can be applied interactively within direct volume rendering. To achieve the best possible results, we propose and analyze a variety of transfer function representations and injection strategies for deep neural networks. Based on the obtained results we also give recommendations applicable in similar volume learning scenarios. Lastly, we show that DVAO generalizes to a variety of modalities, despite being trained on computed tomography data only.