Multi-Temporal Correlation Method for Damage Assessment of Buildings from High-Resolution SAR Images of the 2013 Typhoon Haiyan

2016 ◽  
Vol 11 (3) ◽  
pp. 577-592 ◽  
Author(s):  
Pisut Nakmuenwai ◽  
◽  
Fumio Yamazaki ◽  
Wen Liu ◽  
Keyword(s):  
Three Dimensional ◽  
Correlation Method ◽  
Correlation Coefficients ◽  
Temporal Correlation ◽  
Fish Traps ◽  
Multi Temporal ◽  
Potential Damage ◽  
Cartesian Coordinate ◽  
Color Composite ◽  
High Level

In this study, damage caused by Typhoon Haiyan in the city of Tacloban, Philippines is extracted from COSMO-SkyMed imagery data. A multitemporal correlation map, i.e., a color composite of the backscattering coefficients obtained on different days and their correlation coefficients, is used to indicate changes. The Hyperboloid Change Index is proposed as a measure of the level of destruction. The method is demonstrated in a three-dimensional Cartesian coordinate system to elaborate the relationships among the aforementioned parameters. Compared to other candidate methods, a hyperboloid equation is found to be the most suitable for change detection, and its resulting positive value indicates that the typhoon had a high level of impact on the area. Potential damage areas are extracted using a thresholding operation, and the results are compared to two WorldView-2 satellite images to specifically assess coastal erosion and damage to buildings and offshore fish traps.

scholarly journals Stitching of sensor-navigated 3D ultrasound datasets for the determination of large thyroid volumes – a phantom study

2018 ◽  
Vol 20 (4) ◽  
pp. 480 ◽  
Author(s):  
Martin Freesmeyer ◽  
Leonard Knichel ◽  
Christian Kuehnel ◽  
Thomas Winkens
Keyword(s):  
Ad Hoc ◽  
Clinical Performance ◽  
Three Dimensional ◽  
Thyroid Volume ◽  
Correlation Coefficients ◽  
3D Ultrasound ◽  
Volumetric Analysis ◽  
High Level ◽  
Clinical Equipment

Aims: Thyroid volume has to be measured in goiters prior to radioiodine treatment to calculate the needed amount of radioactivity. Modern clinical equipment for ultrasonography shows the trend to smaller probes, so that larger goiters do not fit any longer into the probe’s field of view. This study evaluated the feasibility and accuracy of stitching procedures applied to thyroid volumetric analysis performed using three-dimensional ultrasound (3D-US).Material and methods: Ad hoc thyroid phantoms of different shapes (regular, nodular, thickened isthmus) and volumes (ranging between 50 and 400 mL) were developed. In 15 such phantoms the left and right lobes were separately scanned, and the 3D-US datasets were then assembled (stitched) using predefined landmarks and dedicated software. Volumetric analysis was then assessed via a conventional ellipsoid model (em) and manual tracing (mt). The correlation of measured and reference volumes was determined using Pearson’s correlation coefficients and Bland and Altman limits of agreement.Results: The results showed a high level of agreement (with correlation coefficients ranging from 0.974 to 0.999) for all shapes and volumes tested, including the largest volume of 400 mL. The mt method, although more time consuming, proved superior to the em.Conclusions: Stitching-mediated thyroid volumetric analysis is accurate, and its clinical performance should be investigated in future studies

Noncontact Three-Dimensional Laser Measuring Device for Tracheoscopy

2002 ◽  
Vol 111 (9) ◽  
pp. 821-827 ◽  
Author(s):  
Andreas Müller ◽  
Mario Schubert ◽  
Eggert Beleites
Keyword(s):  
Unsolved Problem ◽  
Laser Light ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Distortion Correction ◽  
Tracheal Lumen ◽  
Registration System ◽  
Measuring Device ◽  
3 Dimensional ◽  
High Level

Luminal dimension measurements are still an unsolved problem in endoscopy. The goal of our study was to develop a 3-dimensional (3-D) measuring device for endoscopic applications. For this purpose, a fiber probe projecting a ring of laser light (laser diode, 675 nm) was integrated in a position registration system. Software was developed for image analysis, distortion correction, and export of data for 3-D display. Experimental evaluation of measuring accuracy employing plastic tubes and 15 postmortem pig trachea preparations with artificial stenosis indicated a high level of method precision (Pearson's correlation coefficients, r = 0.99 for normal tracheal lumen and r = 0.97 for high-grade stenosis; p < .0001). Our clinical experience with the technique in 10 patients with tracheal stenosis revealed no side effects and encourages us to recommend this method for other endoscopic applications. The method enhances our 3-D grasp of endoscopically examined lesions.

Age-related changes in inter-joint coordination during walking

2014 ◽  
Vol 117 (2) ◽  
pp. 189-198 ◽  
Author(s):  
Espen A. F. Ihlen
Keyword(s):  
Coupling Strength ◽  
Functional Decline ◽  
Three Dimensional ◽  
Correlation Method ◽  
Correlation Coefficients ◽  
Wavelet Coherence ◽  
Coherence Analysis ◽  
Joint Coordination ◽  
Age Related ◽  
Wavelet Coherence Analysis

Existing methods to assess inter-joint coordination in human walking have several important weaknesses. These methods are unable to define 1) the instantaneous changes in coordination within the stride cycle, 2) coordination between multiple joints, or 3) the coupling strength of joint rotations rather than their phase relationships. The present paper introduces a new method called generalized wavelet coherence analysis (GWCA) that solves these three fundamental limitations of previous methods. GWCA combines wavelet coherence analysis with a matrix correlation method to define instantaneous correlation coefficients as the coupling strength for an arbitrary number of joint rotations. The main purpose of the present study is to develop GWCA to quantify inter-joint coordination and thereby assess age-related differences in the coordination of human gaits. Nine young and 19 healthy older persons walked 5 min on a treadmill at three different gait speeds. Joint rotations of the lower extremities were assessed by a Vicon three-dimensional motion capture system. The main results indicated that the older group had significant weaker correlations ( t-tests: P < 0.0001) in the preswing phase compared with the younger group for all gait speeds. The age-related differences in inter-joint coordination were more pronounced than the age-related differences in rotations of the individual joints. The intra-stride changes in inter-joint coordination were in agreement with recent findings of intra-stride modulations in neural activity in the sensorimotor cortex. Thus change in the inter-joint coordination assessed by GWCA might be an early indicator of functional decline.

scholarly journals Multidimensional Scaling Applied to Histogram-Based DNA Analysis

2012 ◽  
Vol 2012 ◽  
pp. 1-11
Author(s):  
António C. Costa ◽  
J. A. Tenreiro Machado ◽  
Maria Dulce Quelhas
Keyword(s):  
Dna Sequences ◽  
Dna Analysis ◽  
Structural Information ◽  
Three Dimensional ◽  
Correlation Method ◽  
Stream Data ◽  
Chromosomal Dna ◽  
Statistical Measures ◽  
Level Information ◽  
High Level

This paper aims to study the relationships between chromosomal DNA sequences of twenty species. We propose a methodology combining DNA-based word frequency histograms, correlation methods, and an MDS technique to visualize structural information underlying chromosomes (CRs) and species. Four statistical measures are tested (Minkowski, Cosine, Pearson product-moment, and Kendallτrank correlations) to analyze the information content of 421 nuclear CRs from twenty species. The proposed methodology is built on mathematical tools and allows the analysis and visualization of very large amounts of stream data, like DNA sequences, with almost no assumptions other than the predefined DNA “word length.” This methodology is able to produce comprehensible three-dimensional visualizations of CR clustering and related spatial and structural patterns. The results of the four test correlation scenarios show that the high-level information clusterings produced by the MDS tool are qualitatively similar, with small variations due to each correlation method characteristics, and that the clusterings are a consequence of the input data and not method’s artifacts.

Guided surgery with 3D printed device: a case report

2020 ◽  
Author(s):  
Michelle Carvalho de Sales ◽  
Rafael Maluza Flores ◽  
Julianny da Silva Guimaraes ◽  
Gustavo Vargas da Silva Salomao ◽  
Tamara Kerber Tedesco ◽  
...  
Keyword(s):  
Operating Time ◽  
Three Dimensional ◽  
Conventional Technique ◽  
Cervical Region ◽  
Mean Deviation ◽  
Apical Region ◽  
Virtual Planning ◽  
Surgical Guide ◽  
Surgical Guides ◽  
High Level

Dental surgeons need in-depth knowledge of the bone tissue status and gingival morphology of atrophic maxillae. The aim of this study is to describe preoperative virtual planning of placement of five implants and to compare the plan with the actual surgical results. Three-dimensional planning of rehabilitation using software programs enables surgical guides to be specially designed for the implant site and manufactured using 3D printing. A patient with five teeth missing was selected for this study. The patient’s maxillary region was scanned with CBCT and a cast model was produced. After virtual planning using ImplantViewer, five implants were placed using a printed surgical guide. Two weeks after the surgical procedure, the patient underwent another CBCT scan of the maxilla. Statistically significant differences were detected between the virtually planned positions and the actual positions of the implants, with a mean deviation of 0.36 mm in the cervical region and 0.7 mm in the apical region. The surgical technique used enables more accurate procedures when compared to the conventional technique. Implants can be better positioned, with a high level of predictability, reducing both operating time and patient discomfort.

Intersession reliability of GPS-based and accelerometer-based physical variables in small-sided games with and without the offside rule

2021 ◽  
pp. 175433712098764
Author(s):  
Igor Junio de Oliveira Custódio ◽  
Gibson Moreira Praça ◽  
Leandro Vinhas de Paula ◽  
Sarah da Glória Teles Bredt ◽  
Fabio Yuzo Nakamura ◽  
...  
Keyword(s):  
Root Mean Square ◽  
Global Positioning System ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Mean Square ◽  
Physical Demands ◽  
Intraclass Correlation Coefficients ◽  
Total Distance ◽  
Global Positioning ◽  
High Level

This study aimed to analyze the intersession reliability of global positioning system (GPS-based) distances and accelerometer-based (acceleration) variables in small-sided soccer games (SSG) with and without the offside rule, as well as compare variables between the tasks. Twenty-four high-level U-17 soccer athletes played 3 versus 3 (plus goalkeepers) SSG in two formats (with and without the offside rule). SSG were performed on eight consecutive weeks (4 weeks for each group), twice a week. The physical demands were recorded using a GPS with an embedded triaxial accelerometer. GPS-based variables (total distance, average speed, and distances covered at different speeds) and accelerometer-based variables (Player Load™, root mean square of the acceleration recorded in each movement axis, and the root mean square of resultant acceleration) were calculated. Results showed that the inclusion of the offside rule reduced the total distance covered (large effect) and the distances covered at moderate speed zones (7–12.9 km/h – moderate effect; 13–17.9 km/h – large effect). In both SSG formats, GPS-based variables presented good to excellent reliability (intraclass correlation coefficients – ICC > 0.62) and accelerometer-based variables presented excellent reliability (ICC values > 0.89). Based on the results of this study, the offside rule decreases the physical demand of 3 versus 3 SSG and the physical demands required in these SSG present high intersession reliability.

scholarly journals Brain capillary structures of schizophrenia cases and controls show a correlation with their neuron structures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rino Saiga ◽  
Masayuki Uesugi ◽  
Akihisa Takeuchi ◽  
Kentaro Uesugi ◽  
Yoshio Suzuki ◽  
...  
Keyword(s):  
Blood Vessels ◽  
Structural Parameters ◽  
Three Dimensional ◽  
Superior Temporal Gyrus ◽  
Anterior Cingulate ◽  
Dimensional Structure ◽  
Constant Diameter ◽  
The Mean ◽  
Cartesian Coordinate ◽  
Micrometer Scale

AbstractBrain blood vessels constitute a micrometer-scale vascular network responsible for supply of oxygen and nutrition. In this study, we analyzed cerebral tissues of the anterior cingulate cortex and superior temporal gyrus of schizophrenia cases and age/gender-matched controls by using synchrotron radiation microtomography or micro-CT in order to examine the three-dimensional structure of cerebral vessels. Over 1 m of cerebral blood vessels was traced to build Cartesian-coordinate models, which were then used for calculating structural parameters including the diameter and curvature of the vessels. The distribution of vessel outer diameters showed a peak at 7–9 μm, corresponding to the diameter of the capillaries. Mean curvatures of the capillary vessels showed a significant correlation to the mean curvatures of neurites, while the mean capillary diameter was almost constant, independent of the cases. Our previous studies indicated that the neurites of schizophrenia cases are thin and tortuous compared to controls. The curved capillaries with a constant diameter should occupy a nearly constant volume, while neurons suffering from neurite thinning should have reduced volumes, resulting in a volumetric imbalance between the neurons and the vessels. We suggest that the observed structural correlation between neurons and blood vessels is related to neurovascular abnormalities in schizophrenia.

Urban network of China from the perspective of population mobility: Three-dimensional co-occurrence of nodes and links

2021 ◽  
pp. 0308518X2199781
Author(s):  
Xinyue Luo ◽  
Mingxing Chen
Keyword(s):  
Three Dimensional ◽  
Geographical Distance ◽  
Two Dimensional ◽  
Population Mobility ◽  
Urban Network ◽  
Urban Networks ◽  
Low Level ◽  
Medium Level ◽  
High Level ◽  
External Connections

The nodes and links in urban networks are usually presented in a two-dimensional(2D) view. The co-occurrence of nodes and links can also be realized from a three-dimensional(3D) perspective to make the characteristics of urban network more intuitively revealed. Our result shows that the external connections of high-level cities are mainly affected by the level of cities(nodes) and less affected by geographical distance, while medium-level cities are affected by the interaction of the level of cities(nodes) and geographical distance. The external connections of low-level cities are greatly restricted by geographical distance.

scholarly journals The patellofemoral morphology and the normal predicted value of tibial tuberosity-trochlear groove distance in the Chinese population

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhe Li ◽  
Guanzhi Liu ◽  
Run Tian ◽  
Ning Kong ◽  
Yue Li ◽  
...  
Keyword(s):  
Individual Differences ◽  
Chinese Population ◽  
Pearson Correlation ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Tibial Tuberosity ◽  
Trochlear Groove ◽  
Lasso Regression ◽  
Cross Sectional ◽  
Anterior Posterior

Abstract Background Our objective was to obtain normal patellofemoral measurements to analyse sex and individual differences. In addition, the absolute values and indices of tibial tuberosity-trochlear groove (TT-TG) distances are still controversial in clinical application. A better method to enable precise prediction is still needed. Methods Seventy-eight knees of 78 participants without knee pathologies were included in this cross-sectional study. A CT scan was conducted for all participants and three-dimensional knee models were constructed using Mimics and SolidWorks software. We measured and analysed 19 parameters including the TT-TG distance and dimensions and shapes of the patella, femur, tibia, and trochlea. LASSO regression was used to predict the normal TT-TG distances. Results The dimensional parameters, TT-TG distance, and femoral aspect ratio of the men were significantly larger than those of women (all p values < 0.05). However, after controlling for the bias from age, height, and weight, there were no significant differences in TT-TG distances and anterior-posterior dimensions between the sexes (all p values > 0.05). The Pearson correlation coefficients between the anterior femoral offset and other indexes were consistently below 0.3, indicating no relationship or a weak relationship. Similar results were observed for the sulcus angle and the Wiberg index. Using LASSO regression, we obtained four parameters to predict the TT-TG distance (R2 = 0.5612, p < 0.01) to achieve the optimal accuracy and convenience. Conclusions Normative data of patellofemoral morphology were provided for the Chinese population. The anterior-posterior dimensions of the women were thicker than those of men for the same medial-lateral dimensions. More attention should be paid to not only sex differences but also individual differences, especially the anterior condyle and trochlea. In addition, this study provided a new method to predict TT-TG distances accurately.

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