scholarly journals A Pulmonary Vascular Extraction Algorithm from Chest CT/CTA Images

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Shihui Xu ◽  
Ziming Zhang ◽  
Qinghua Zhou ◽  
Wei Shao ◽  
Wenjun Tan
Keyword(s):  
Experimental Data ◽  
Lung Parenchyma ◽  
High Accuracy ◽  
Chest Ct ◽  
Second Step ◽  
Original Image ◽  
Pulmonary Vessels ◽  
Extraction Algorithm ◽  
Segmentation Accuracy ◽  
Data Source

Segmentation of pulmonary vessels in CT/CTA images can help physicians better determine the patient’s condition and treatment. However, due to the complexity of CT images, existing methods have limitations in the segmentation of pulmonary vessels. In this paper, a method based on the separation of pulmonary vessels in CT/CTA images is investigated. The method is divided into two steps: in the first step, the lung parenchyma is extracted using the Unet++ algorithm, which can effectively reduce the oversegmentation rate; in the second step, the pulmonary vessels in the lung parenchyma are extracted using nnUnet. According to the obtained lung parenchyma segmentation results, the “AND” operation is performed on the original image and the lung parenchyma segmentation results, and only the blood vessels within the lung parenchyma are segmented, which reduces the interference of external tissues and improves the segmentation accuracy. The experimental data source used CT/CTA images acquired from the partner hospital. After the experiments were performed on a total of 67 sets of images, the accuracy of CT and CTA images reached 85.1% and 87.7%, respectively. The comparison of whether to segment the lung parenchyma and with other conventional methods was also performed, and the experimental results showed that the algorithm in this paper has high accuracy.

A New Auto-Extraction Algorithm of Multi-Size Lunar Craters Based on the Chang’E Data

2014 ◽  
Vol 599-601 ◽  
pp. 1340-1345 ◽  
Author(s):  
Han Liu ◽  
Xiao Lin Tian ◽  
Ao Ao Xu
Keyword(s):  
Noise Reduction ◽  
Lunar Surface ◽  
Second Step ◽  
Automatic Extraction ◽  
Original Image ◽  
Circle Fitting ◽  
Extraction Algorithm ◽  
Lunar Craters

A new algorithm of automatic extraction of multi-size lunar craters has been proposed. The proposed algorithm could detect multi-size craters by using different filters in multi-steps, which is a loop to detect multi-size craters by different size filters. In the first step, the new algorithm will use a larger filter to reduce noise and detect larger craters by using circle fitting at de-noised image. After marked these areas in the original image, it will remove those detected crater areas from the original image and do the noise reduction with a smaller filter again. The new algorithm will repeat the second step several times to finish the detection of whole image. Finally the new algorithm will merge results of these steps and output a final result. The new algorithm has been tested based on the Chang’E Data in the Matlab environment. The result has shown that this new algorithm does have the ability to detect different sized craters on the lunar surface, which has pointed a way to detect secondary craters automatically.

scholarly journals Fully Automated Segmentation of Lung Parenchyma Using Break and Repair Strategy

2019 ◽  
Vol 28 (2) ◽  
pp. 275-289 ◽  
Author(s):  
S. Pramod Kumar ◽  
Mrityunjaya V. Latte
Keyword(s):  
Active Contour ◽  
Lung Parenchyma ◽  
Threshold Selection ◽  
Chain Code ◽  
Repair Strategy ◽  
Automated Method ◽  
Segmentation Methods ◽  
Segmentation Accuracy ◽  
Pulmonary Parenchyma ◽  
Optimal Threshold Selection

Abstract The traditional segmentation methods available for pulmonary parenchyma are not accurate because most of the methods exclude nodules or tumors adhering to the lung pleural wall as fat. In this paper, several techniques are exhaustively used in different phases, including two-dimensional (2D) optimal threshold selection and 2D reconstruction for lung parenchyma segmentation. Then, lung parenchyma boundaries are repaired using improved chain code and Bresenham pixel interconnection. The proposed method of segmentation and repairing is fully automated. Here, 21 thoracic computer tomography slices having juxtapleural nodules and 115 lung parenchyma scans are used to verify the robustness and accuracy of the proposed method. Results are compared with the most cited active contour methods. Empirical results show that the proposed fully automated method for segmenting lung parenchyma is more accurate. The proposed method is 100% sensitive to the inclusion of nodules/tumors adhering to the lung pleural wall, the juxtapleural nodule segmentation is >98%, and the lung parenchyma segmentation accuracy is >96%.

scholarly journals Automatic speech segmentation using throat-acoustic correlation coefficients

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Rustam Rafikovich Mussabayev ◽  
Maksat N. Kalimoldayev ◽  
Yedilkhan N. Amirgaliyev ◽  
Timur R. Mussabayev
Keyword(s):  
Large Volume ◽  
Automatic Segmentation ◽  
Correlation Coefficients ◽  
High Accuracy ◽  
Speech Segmentation ◽  
Preliminary Training ◽  
Effi Ciency ◽  
Segmentation Accuracy ◽  
New Type ◽  
The Given

Abstract This work considers one of the approaches to the solution of the task of discrete speech signal automatic segmentation. The aim of this work is to construct such an algorithm which should meet the following requirements: segmentation of a signal into acoustically homogeneous segments, high accuracy and segmentation speed, unambiguity and reproducibility of segmentation results, lack of necessity of preliminary training with the use of a special set consisting of manually segmented signals. Development of the algorithm which corresponds to the given requirements was conditioned by the necessity of formation of automatically segmented speech databases that have a large volume. One of the new approaches to the solution of this task is viewed in this article. For this purpose we use the new type of informative features named TAC-coefficients (Throat-Acoustic Correlation coefficients) which provide sufficient segmentation accuracy and effi- ciency.

scholarly journals AB1139 DIAGNOSTICIS AND PROGNOSTICIS SIGNIFICANCE OF CHEST CT EVALUATION OF SMALL PULMONARY VESSELS IN CONNECTIVE TISSUE DISEASES WITH PULMONARY ARTERIAL HYPERTENSION.

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1859.1-1860
Author(s):  
Y. Zhang ◽  
N. Zhang ◽  
Y. Zhu ◽  
Q. Wang ◽  
L. Zhou
Keyword(s):  
Pulmonary Hypertension ◽  
Pulmonary Arterial Hypertension ◽  
Connective Tissue ◽  
Arterial Hypertension ◽  
Vascular Remodeling ◽  
Connective Tissue Diseases ◽  
Chest Ct ◽  
Pulmonary Vessels ◽  
Ct Evaluation ◽  
Pulmonary Arterial

Background:Pulmonary arterial hypertension (PAH) is a fatal complication of connective tissue diseases (CTDs). Chest CT has been increasingly used in the evaluation of patients with suspected PH noninvasively but there is a paucity of studies.Objectives:Our study was aimed to investigate the cross-sectional area (CSA) of small pulmonary vessels on chest CT for the diagnosis and prognosis of CTD-PAH.Methods:This retrospective study analyzed the data of thirty-four patients with CTD-PAH who were diagnosed by right heart catheterization (RHC) and underwent chest CT between March 2011 and October 2019. We measured the percentage of total CSA of vessels<5 mm2and 5-10 mm2as a percentage of total lung area (%CSA<5and %CSA5-10) on Chest CT. Furthermore, the association of %CSA with mean pulmonary artery pressure (mPAP) was also investigated. Besides, these patients were followed up until October 2019, and Kaplan-Meier survival curves were generated for the evaluation of prognosis.Results:Patients with CTD-PAH had significantly higher %CSA5-10than CTD-nPAH (p=0.001), %CSA5-10in CTD-S-PAH and IPAH was significantly higher than CTD-LM-PAH and COPD-PH (p<0.01). There was a positive correlation between %CSA5-10and mPAP in CTD-PAH (r=0.447, p=0.008). Considering %CSA5-10above 0.38 as a threshold level, the sensitivity and specificity were found to be 0.824 and 0.706, respectively. Patients with %CSA5-10≥0.38 had a lower survival rate than those with %CSA5-10<0.38 (p=0.049).Conclusion:Quantitative parameter, %CSA5-10on Chest CT might serve a crucial differential diagnostic tool for different types of PH. %CSA5-10≥0.38 is a prognostic indicator for evaluation of CTD-PAH.References:[1]Galie N, Humbert M, Vachiery JL, et al. 2015 ESC/ERS Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension. Rev Esp Cardiol (Engl Ed). 2016;69(2):177.[2]Siddiqui I, Rajagopal S, Brucker A, et al. Clinical and Echocardiographic Predictors of Outcomes in Patients With Pulmonary Hypertension. Am J Cardiol. 2018;122(5):872-878.[3]Coste F, Dournes G, Dromer C, et al. CT evaluation of small pulmonary vessels area in patients with COPD with severe pulmonary hypertension. Thorax. 2016;71(9):830-837.[4]Freed BH, Collins JD, Francois CJ, et al. MR and CT Imaging for the Evaluation of Pulmonary Hypertension. JACC Cardiovasc Imaging. 2016;9(6):715-732.[5]Pietra GG, Capron F, Stewart S, et al. Pathologic assessment of vasculopathies in pulmonary hypertension. J Am Coll Cardiol. 2004;43(12 Suppl S):25S-32S.[6]Zanatta E, Polito P, Famoso G, et al. Pulmonary arterial hypertension in connective tissue disorders: Pathophysiology and treatment. Exp Biol Med (Maywood). 2019;244(2):120-131.[7]Rabinovitch M, Guignabert C, Humbert M, Nicolls MR. Inflammation and immunity in the pathogenesis of pulmonary arterial hypertension. Circ Res. 2014;115(1):165-175.[8]Thenappan T, Ormiston ML, Ryan JJ, Archer SL. Pulmonary arterial hypertension: pathogenesis and clinical management. BMJ. 2018;360:j5492.[9]Thompson AAR, Lawrie A. Targeting Vascular Remodeling to Treat Pulmonary Arterial Hypertension. Trends Mol Med. 2017;23(1):31-45.[10]Shimoda LA, Laurie SS. Vascular remodeling in pulmonary hypertension. J Mol Med (Berl). 2013;91(3):297-309.[11]Rabinovitch M. Molecular pathogenesis of pulmonary arterial hypertension. J Clin Invest. 2012;122(12):4306-4313.[12]Seeger W, Adir Y, Barbera JA, et al. Pulmonary hypertension in chronic lung diseases. J Am Coll Cardiol. 2013;62(25 Suppl):D109-116.Acknowledgments:Thanks to all patients involved in this retrospective study. Thanks go to every participant who participated in this study for their enduring efforts in working with participants to complete the study. Thanks to Liangmin Wei for helping us with statistics analysis.Disclosure of Interests:None declared

The Revised Universal Slope Method to Predict the Low-Cycle Fatigue Lives of Elbow and Tee Pipes

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Hiun Nagamori ◽  
Koji Takahashi
Keyword(s):  
Experimental Data ◽  
Internal Pressure ◽  
Low Cycle Fatigue ◽  
Experimental Studies ◽  
High Accuracy ◽  
Universal Method ◽  
Cycle Fatigue ◽  
Element Analysis ◽  
Slope Method ◽  
Stress States

The stress states of elbow and tee pipes are complex and different from those of straight pipes. The low-cycle fatigue lives of elbows and tees cannot be predicted by Manson's universal slope method; however, a revised universal method proposed by Takahashi et al. was able to predict with high accuracy the low-cycle fatigue lives of elbows under combined cyclic bending and internal pressure. The objective of this study was to confirm the validity of the revised universal slope method for the prediction of low-cycle fatigue behaviors of elbows and tees of various shapes and dimensions under conditions of in-plane bending and internal pressure. Finite element analysis (FEA) was carried out to simulate the low-cycle fatigue behaviors observed in previous experimental studies of elbows and tees. The low-cycle fatigue behaviors, such as the area of crack initiation, the direction of crack growth, and the fatigue lives, obtained by the analysis were compared with previously obtained experimental data. Based on this comparison, the revised universal slope method was found to accurately predict the low-cycle fatigue behaviors of elbows and tees under internal pressure conditions regardless of differences in shape and dimensions.

Role of diagnostic imaging in diagnosis by Covid-19

2020 ◽  
Author(s):  
Coda Marco ◽  
Sica Federica ◽  
Finelli Mirko ◽  
Ungaro Gaetano ◽  
Sica Alfonso Marco
Keyword(s):  
Differential Diagnosis ◽  
Lung Parenchyma ◽  
Chest Ct ◽  
Initial Assessment ◽  
X Rays ◽  
Radiological Imaging ◽  
Laboratory Examinations ◽  
Clinical Conditions

The diagnosis from Covid-19 provides the set of several examinations such as: clinical examinations, laboratory examinations, radiographic examinations. Using radiological imaging, RX and chest CT, it is possible to evaluate the impairment of lung function and thanks to this aspect it is possible to define the severity and clinical conditions of the patient. In this way, it allows timely therapeutic intervention especially if the patient shows a mild condition in such a way as to avoid the onset of further complications. Chest X-rays allow both an initial assessment of patients and the possibility to perform a differential diagnosis towards other possible causes of lung parenchyma involvement. The CT scan, which highlights the peculiar characteristics of COVID pneumonia, is performed both as diagnostic confirmation and in the patient’s follow-up.

scholarly journals Scalar isoscalar form factors for energies above 1 GeV

2019 ◽  
Vol 202 ◽  
pp. 06002
Author(s):  
Stefan Ropertz ◽  
Christoph Hanhart ◽  
Bastian Kubis
Keyword(s):  
Experimental Data ◽  
Scattering Amplitudes ◽  
Form Factors ◽  
Padé Approximants ◽  
High Accuracy ◽  
Data Description ◽  
Pade Approximants ◽  
Low Energies

We present a new parametrization for scattering amplitudes and form factors, which is consistent with high-accuracy dispersive representations at low energies but at the same time allows for a data description of higher mass resonances such as the f0(1500) and f0(2020). The formalism is general and thus can be applied to many decay processes. As an example we discuss the decay of $ \bar {B}_s^0 $ → J/ψππ(KK). From the amplitude fixed in a fit to the experimental data pole positions and residues are extracted via Padé approximants.

scholarly journals Almost Exact Computation of Eigenvalues in Approximate Differential Problems

2019 ◽  
Vol 24 (4) ◽  
pp. 96 ◽  
Author(s):  
José M. A. Matos ◽  
Maria João Rodrigues
Keyword(s):  
Eigenvalue Problems ◽  
High Accuracy ◽  
Second Step ◽  
Matlab Toolbox ◽  
Differential Problem ◽  
Algebraic Problem ◽  
Polynomial Expression ◽  
Computation Of Eigenvalues ◽  
Potential Use ◽  
Mathematics And Physics

Differential eigenvalue problems arise in many fields of Mathematics and Physics, often arriving, as auxiliary problems, when solving partial differential equations. In this work, we present a method for eigenvalues computation following the Tau method philosophy and using Tau Toolbox tools. This Matlab toolbox was recently presented and here we explore its potential use and suitability for this problem. The first step is to translate the eigenvalue differential problem into an algebraic approximated eigenvalues problem. In a second step, making use of symbolic computations, we arrive at the exact polynomial expression of the determinant of the algebraic problem matrix, allowing us to get high accuracy approximations of differential eigenvalues.

scholarly journals Chronic necrotizing pulmonary aspergillosis

2011 ◽  
Vol 68 (11) ◽  
pp. 988-991 ◽  
Author(s):  
Aleksandra Lovrenski ◽  
Milana Panjkovic ◽  
Zivka Eri ◽  
Istvan Klem ◽  
Djordje Povazan ◽  
...  
Keyword(s):  
Unusual Case ◽  
Lung Parenchyma ◽  
Left Lobe ◽  
Chest Ct ◽  
Bronchial Biopsy ◽  
Pulmonary Aspergillosis ◽  
Chronic Necrotizing Pulmonary Aspergillosis ◽  
Systemic Symptoms ◽  
Acute And Chronic Inflammation ◽  
Unusual Case Report

Introduction. Chronic necrotizing pulmonary aspergillosis (CNPA) is a cavitary, infectious process of lung parenchyma with slow progressive course. Vascular invasion and dissemination to other organs are unusual. Case report. We presented a 25-year old man with bilineal acute leukaemia who developed pulmonary and systemic symptoms. Chest CT showed nodular consolidations and cavitary lesions in both lungs. Bronchial biopsy revealed necrotic hyphae but it was negative for Aspergillus by culture. Serum was positive for antibodies to Aspergillus, but it was negative for antigens. A thoracoscopic lung biopsy of the upper left lobe revealed necrosis of lung tissue, with acute and chronic inflammation of the cavity wall and the presence of hyphae consistent with Aspergillus species. Conclusion. Although confirmation of the diagnosis is difficult, a combination of characteristic clinical, radiological and histological findings and either serological results positive for Aspergillus or the isolation of Aspergillus from respiratory samples are highly indicative of CNPA.

scholarly journals Spatial Context-Based Local Toponym Extraction and Chinese Textual Address Segmentation from Urban POI Data

2020 ◽  
Vol 9 (3) ◽  
pp. 147 ◽  
Author(s):  
Xi Kuai ◽  
Renzhong Guo ◽  
Zhijun Zhang ◽  
Biao He ◽  
Zhigang Zhao ◽  
...  
Keyword(s):  
Input Data ◽  
Geographic Area ◽  
Spatial Context ◽  
Second Step ◽  
Chinese Word Segmentation ◽  
Textual Information ◽  
Points Of Interest ◽  
Data Source ◽  
Series Of Experiments ◽  
Segmentation Models

Georeferencing by place names (known as toponyms) is the most common way of associating textual information with geographic locations. While computers use numeric coordinates (such as longitude-latitude pairs) to represent places, people generally refer to places via their toponyms. Query by toponym is an effective way to find information about a geographic area. However, segmenting and parsing textual addresses to extract local toponyms is a difficult task in the geocoding field, especially in China. In this paper, a local spatial context-based framework is proposed to extract local toponyms and segment Chinese textual addresses. We collect urban points of interest (POIs) as an input data source; in this dataset, the textual address and geospatial position coordinates correspond at a one-to-one basis and can be easily used to explore the spatial distribution of local toponyms. The proposed framework involves two steps: address element identification and local toponym extraction. The first step identifies as many address element candidates as possible from a continuous string of textual addresses for each urban POI. The second step focuses on merging neighboring candidate pairs into local toponyms. A series of experiments are conducted to determine the thresholds for local toponym extraction based on precision-recall curves. Finally, we evaluate our framework by comparing its performance with three well-known Chinese word segmentation models. The comparative experimental results demonstrate that our framework achieves a better performance than do other models.

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