scholarly journals Segmentation of Lath-Like Structures via Localized Identification of Directionality in a Complex-Phase Steel

2020 ◽  
Vol 9 (5) ◽  
pp. 709-720
Author(s):  
Martin Müller ◽  
Gerd Stanke ◽  
Ulrich Sonntag ◽  
Dominik Britz ◽  
Frank Mücklich
Keyword(s):  
Granular Bainite ◽  
Easy Access ◽  
Segmentation Result ◽  
Complex Phase ◽  
Segmentation Approach ◽  
Promising Solution ◽  
Segmentation Task ◽  
Two Parameters ◽  
Automated Procedures ◽  
Adjustment Of Parameters

AbstractIn this work, a segmentation approach based on analyzing local orientations and directions in an image, in order to distinguish lath-like from granular structures, is presented. It is based on common image processing operations. A window of appropriate size slides over the image, and the gradient direction and its magnitude inside this window are determined for each pixel. The histogram of all possible directions yields the main direction and its directionality. These two parameters enable the extraction of window positions which represent lath-like structures, and procedures to join these positions are developed. The usability of this approach is demonstrated by distinguishing lath-like bainite from granular bainite in so-called complex-phase steels, a segmentation task for which automated procedures are not yet reported. The segmentation results are in accordance with the regions recognized by human experts. The approach’s main advantages are its use on small sets of images, the easy access to the segmentation process and therefore a targeted adjustment of parameters to achieve the best possible segmentation result. Thus, it is distinct from segmentation using deep learning which is becoming more and more popular and is a promising solution for complex segmentation tasks, but requires large image sets for training and is difficult to interpret.

Medical Volumes Segmentation Approach Based on Level Set Method

2011 ◽  
Vol 65 ◽  
pp. 173-176
Author(s):  
Zhong Wei Li ◽  
Ming Jiu Ni ◽  
Zhen Kuan Pan
Keyword(s):  
Magnetic Resonance Angiography ◽  
Level Set Method ◽  
Level Set ◽  
Medical Application ◽  
Vascular Structure ◽  
Thin Structures ◽  
Proposed Model ◽  
Segmentation Approach ◽  
Computer Based ◽  
Segmentation Task

Volumes segmentation is an important part of computer based medical application for diagnosis and analysis of anatomical data. A segmentation approach based on the level set method is proposed for accurately extracting vasculature from magnetic resonance angiography (MRA) volumes in this paper. The proposed model has a boundary alignment term that is used for segmentation of thin structures. Finally the proposed model is applied to the segmentation of MRA volumes. The result shows that the proposed model by us can complete the segmentation task of vascular structure and cannot complete the same task by the model without boundary alignment term

scholarly journals An Integrated Strategy toward the Extraction of Contour and Region of Sonar Images

2020 ◽  
Vol 8 (8) ◽  
pp. 595
Author(s):  
Huipu Xu ◽  
Wenjie Lu ◽  
Meng Joo Er
Keyword(s):  
Level Set ◽  
Lattice Boltzmann ◽  
Initial Contour ◽  
Segmentation Result ◽  
Clustering Method ◽  
Region Segmentation ◽  
Sonar Images ◽  
Segmentation Task ◽  
Boltzmann Method ◽  
Improved Methods

In this paper, an integrated underwater sonar image extraction strategy, which combines two improved methods, namely the level set method (LSM) and the Lattice Boltzmann Method (LBM), is proposed. First, sonar images are processed by a clustering method and a connected domain analysis to generate the target minimum rectangle frame. Next, the segmentation task is decomposed into two subtasks, namely a coarse segmentation task to obtain the initial contour and a fine segmentation task after embedding the initial contour. Finally, the improved LSM is used to obtain the target contour, and the coarse contour of the segment is embedded into the LBM to obtain the region segmentation of the target in the sonar images. The main contributions of the paper are as follows: (1) The contours and regions of the sonar images are extracted simultaneously. (2) The original LBM method is enhanced to solve the level set iteration problem. (3) The region segmentation with the original image background is extracted, and a more intuitive region segmentation result than that of directly extracting the contour of the level set is achieved. Experimental results based on four evaluation indices of image segmentation show that our method is effective, accurate, and superior to other existing methods.

Co-Occurrence-Based Error Correction Approach to Word Segmentation

2012 ◽  
pp. 354-364 ◽  
Author(s):  
Ekawat Chaowicharat ◽  
Kanlaya Naruedomkul
Keyword(s):  
Error Correction ◽  
Data Bank ◽  
Word Segmentation ◽  
Input String ◽  
Segmentation Result ◽  
Training Corpus ◽  
Word Sequence ◽  
Segmentation Algorithms ◽  
Segmentation Approach ◽  
Error Risk

A number of word segmentation algorithms have been offered in the past; however, there is still room for improvement. Co-occurrence-Based Error Correction (CBEC), the proposed approach in this chapter, is a novel Thai word segmentation approach that was designed to provide accurate segmentation results based on context and purpose. CBEC quickly segments the input string using any available algorithm; maximal matching was used in the experiment. Next, CBEC checks its segmentation output against an error risk data bank to determine if there is any error risk. The error risk data bank is developed based on a training corpus. The current version of the error risk bank was based on the training corpus available at BEST 2009. Then, CBEC re-segments the input string using the co-occurrence score of the word sequence to ensure the accuracy of the segmentation result.

scholarly journals An Overview of Traditional Chinese Herbal Formulae and a Proposal of a New Code System for Expressing the Formula Titles

2004 ◽  
Vol 1 (2) ◽  
pp. 125-132 ◽  
Author(s):  
Yeong-Deug Yi ◽  
Il-Moo Chang
Keyword(s):  
Key Words ◽  
Chinese Literature ◽  
Analytical Data ◽  
Easy Access ◽  
Herbal Therapy ◽  
Code System ◽  
Chinese Herbal ◽  
Chinese Herbal Therapy ◽  
Herbal Formulae ◽  
Two Parameters

Traditional Chinese herbal therapy can be characterized by the use of a large number of multi-herb formulae. To provide modern and Western scientists without knowledge of Chinese literature and cultural background easy access to information, a database with a total of 11 810 traditional Chinese herbal formulae was constructed. All the information was then translated into understandable scientific terms in English. While coining the formula titles in English, we discovered some principles governing the naming of titles by using computer analysis. In addition, we observed that about 92% of the formulae are in the range of single-herb formulae to thirteen-herb formulae. Most large number-herb formulae are formulated by combining pre-existing smaller number-herb formulae. The King herbs (neh019-inl-01) with major therapeutic activity in a multi-herb formula were identified by the formulation concept using two parameters: the herbal dose and the herbal drug property (the degree of toxicity). Based on such analytical data, we established an English code system representing all formula titles written in ideographic Chinese characters: an array of important key words such as ‘Herbal name in Latin + Efficacy (Target organs) + Preparation form + Number of herbs.’ By searching the English version of the database with any of the above key words, a variety of information on the status of traditional Chinese herbal therapy can be accessed.

scholarly journals Malaria Screener: a smartphone application for automated malaria screening

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Hang Yu ◽  
Feng Yang ◽  
Sivaramakrishnan Rajaraman ◽  
Ilker Ersoy ◽  
Golnaz Moallem ◽  
...  
Keyword(s):  
Light Microscopy ◽  
Malaria Diagnosis ◽  
Smartphone Application ◽  
Mobile App ◽  
Easy Access ◽  
Screening Process ◽  
Computing Power ◽  
Resource Limited ◽  
Promising Solution

Abstract Background Light microscopy is often used for malaria diagnosis in the field. However, it is time-consuming and quality of the results depends heavily on the skill of microscopists. Automating malaria light microscopy is a promising solution, but it still remains a challenge and an active area of research. Current tools are often expensive and involve sophisticated hardware components, which makes it hard to deploy them in resource-limited areas. Results We designed an Android mobile application called Malaria Screener, which makes smartphones an affordable yet effective solution for automated malaria light microscopy. The mobile app utilizes high-resolution cameras and computing power of modern smartphones to screen both thin and thick blood smear images for P. falciparum parasites. Malaria Screener combines image acquisition, smear image analysis, and result visualization in its slide screening process, and is equipped with a database to provide easy access to the acquired data. Conclusion Malaria Screener makes the screening process faster, more consistent, and less dependent on human expertise. The app is modular, allowing other research groups to integrate their methods and models for image processing and machine learning, while acquiring and analyzing their data.

scholarly journals Design and Development of Complex Phase Steels with Improved Combination of Strength and Stretch-Flangeability

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 824 ◽  
Author(s):  
Alexis Graux ◽  
Sophie Cazottes ◽  
David De Castro ◽  
David San-Martín ◽  
Carlos Capdevila ◽  
...  
Keyword(s):  
Expansion Ratio ◽  
Granular Bainite ◽  
Coiling Temperature ◽  
Design And Development ◽  
Complex Phase ◽  
Austenite Grain ◽  
Hole Expansion Ratio ◽  
Grain Growth Behavior ◽  
Hot Rolled ◽  
Austenite Grain Growth

This study presents the design and development of a hot-rolled bainitic steel, presenting a good combination of strength and stretch-flangeability, for automotive applications. Ti, Nb, and Mo were added in the steel composition in order to control austenite grain sizes, enhance precipitation hardening, and promote the formation of bainite. This study focuses on the effect of process parameters on final microstructures and mechanical properties. These parameters are the finishing rolling temperature, which conditions the austenite microstructure before its decomposition, and the coiling temperature, which conditions the nature and morphology of the ferritic phases transformed. A preliminary study allowed to determine the austenite grain growth behavior during reheating, the recrystallization kinetics, and the continuous cooling transformation curves of the studied steel. Then, a first set of parameters was tested at a semi-industrial scale, which confirmed that the best elongation properties were obtained for homogeneous bainitic lath/granular microstructures, that can be produced by choosing a coiling temperature of 500 ∘ C . When choosing those parameters for the final industrial trial, the microstructure obtained consisted of a homogeneous lath/granular bainite mixture that presented a Ultimate Tensile Strength of 830 MPa and a Hole Expansion Ratio exceeding 70%.

Photo-electric Hβ and uvby photometry

1966 ◽  
Vol 24 ◽  
pp. 170-180
Author(s):  
D. L. Crawford
Keyword(s):  
Narrow Band ◽  
Line Strength ◽  
Interference Filter ◽  
B Stars ◽  
Relative Line ◽  
The Mean ◽  
F Stars ◽  
Two Parameters ◽  
Filter Photometry ◽  
The Continuum

Early in the 1950's Strömgren (1, 2, 3, 4, 5) introduced medium to narrow-band interference filter photometry at the McDonald Observatory. He used six interference filters to obtain two parameters of astrophysical interest. These parameters he calledlandc, for line and continuum hydrogen absorption. The first measured empirically the absorption line strength of Hβby means of a filter of half width 35Å centered on Hβand compared to the mean of two filters situated in the continuum near Hβ. The second index measured empirically the Balmer discontinuity by means of a filter situated below the Balmer discontinuity and two above it. He showed that these two indices could accurately predict the spectral type and luminosity of both B stars and A and F stars. He later derived (6) an indexmfrom the same filters. This index was a measure of the relative line blanketing near 4100Å compared to two filters above 4500Å. These three indices confirmed earlier work by many people, including Lindblad and Becker. References to this earlier work and to the systems discussed today can be found in Strömgren's article inBasic Astronomical Data(7).

Radiation Damage of Support Films

1981 ◽  
Vol 39 ◽  
pp. 28-29
Author(s):  
H.A. Cohen ◽  
W. Chiu
Keyword(s):  
Transfer Function ◽  
Low Temperatures ◽  
Carbon Support ◽  
Contrast Transfer Function ◽  
Electron Dose ◽  
Imaging Parameters ◽  
Negative Stain ◽  
Phase Corrections ◽  
Two Parameters ◽  
Medium Dose

The goal of imaging the finest detail possible in biological specimens leads to contradictory requirements for the choice of an electron dose. The dose should be as low as possible to minimize object damage, yet as high as possible to optimize image statistics. For specimens that are protected by low temperatures or for which the low resolution associated with negative stain is acceptable, the first condition may be partially relaxed, allowing the use of (for example) 6 to 10 e/Å2. However, this medium dose is marginal for obtaining the contrast transfer function (CTF) of the microscope, which is necessary to allow phase corrections to the image. We have explored two parameters that affect the CTF under medium dose conditions.Figure 1 displays the CTF for carbon (C, row 1) and triafol plus carbon (T+C, row 2). For any column, the images to which the CTF correspond were from a carbon covered hole (C) and the adjacent triafol plus carbon support film (T+C), both recorded on the same micrograph; therefore the imaging parameters of defocus, illumination angle, and electron statistics were identical.

Applications of Scanning Microscopy in Biomedical Research

1968 ◽  
Vol 26 ◽  
pp. 354-355
Author(s):  
T. L. Hayes
Keyword(s):  
Information Content ◽  
Biomedical Research ◽  
Biomedical Applications ◽  
Three Dimensional ◽  
Dental Enamel ◽  
Resolving Power ◽  
Whole Mount ◽  
Two Parameters ◽  
Content Information ◽  
Sectioned Tissue

Biomedical applications of the scanning electron microscope (SEM) have increased in number quite rapidly over the last several years. Studies have been made of cells, whole mount tissue, sectioned tissue, particles, human chromosomes, microorganisms, dental enamel and skeletal material. Many of the advantages of using this instrument for such investigations come from its ability to produce images that are high in information content. Information about the chemical make-up of the specimen, its electrical properties and its three dimensional architecture all may be represented in such images. Since the biological system is distinctive in its chemistry and often spatially scaled to the resolving power of the SEM, these images are particularly useful in biomedical research.In any form of microscopy there are two parameters that together determine the usefulness of the image. One parameter is the size of the volume being studied or resolving power of the instrument and the other is the amount of information about this volume that is displayed in the image. Both parameters are important in describing the performance of a microscope. The light microscope image, for example, is rich in information content (chemical, spatial, living specimen, etc.) but is very limited in resolving power.

Granular bainite or granular ferrite? A preliminary TEM investigation of an HSLA-100 steel

1991 ◽  
Vol 49 ◽  
pp. 584-585
Author(s):  
R. Varughese ◽  
S. W. Thompson ◽  
P. R. Howell
Keyword(s):  
Room Temperature ◽  
Transformation Products ◽  
Accurate Description ◽  
Granular Bainite ◽  
Preliminary Results ◽  
The Past ◽  
Light Micrograph ◽  
Multiphase Reaction ◽  
Detailed Nature

Ever since Habraken and Economopoulos first employed the term granular bainite to classify certain unconventional transformation products in continuously cooled steels, the term has been widely accepted and used, despite the lack of a clear consensus as to the detailed nature of the transformation products which constitute granular bainite. This paper presents the preliminary results of a TEM investigation of an 0.04 wt% C, copper-containing steel (designated HSLA-100). It is suggested that the term granular ferrite rather than granular bainite is a more accurate description of this multiphase reaction product.Figure 1 is a light micrograph of a sample which had been air-cooled from 900°C to room temperature. The microstructure is typical of that which has been termed granular bainite in the past and appears to consist of equiaxed ferritic grains together with other minor transformation products. In order to examine these structures in more detail, both continuously cooled and isothermally transformed and quenched materials have been examined with TEM. Granular bainite has been found in virtually all samples.

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