Fitting Ellipse Based on the Dual Conic Model

2013 ◽  
Vol 670 ◽  
pp. 80-84
Author(s):  
C. Zhao ◽  
Mao Li Fu ◽  
J.T. Cheng
Keyword(s):  
Computational Efficiency ◽  
Dual Space ◽  
The Other ◽  
Dual Representation ◽  
Conic Model ◽  
Gradient Information ◽  
Edge Points ◽  
Low Sensitivity

This paper presents an operator that fitting the parameters of ellipses features, and improves the computational efficiency. Based on the dual conic model, this operator directly uses the raw gradient information in the neighborhood of an ellipse’s boundary, which use tangent lines and to apply the estimation in the dual space, so that avoiding the step of precisely extracting individual edge points. Moreover, under the dual representation, the dual conic can easily be constrained to a dual ellipse when minimizing the algebraic distance. The operator presents low sensitivity to noise and is compared to other estimation approaches, which shows good results, the accuracy of this operator is the highest, the time of this operator is moderate that compared with the other methods, and fall within acceptable levels, and in the case of noise or blur, the algorithm have shown very good robustness, in the practical environment can fit the parameters of the ellipse accurately.

The Study of Target Points Center Extracting and Matching in Calibration

2010 ◽  
Vol 136 ◽  
pp. 167-171
Author(s):  
Bo Zhou ◽  
Dong Ping Wang ◽  
Jian Yang
Keyword(s):  
Computer Vision ◽  
Dual Space ◽  
Intermediate Stage ◽  
Space Representation ◽  
Gradient Information ◽  
Edge Points ◽  
Ransac Algorithm ◽  
Ellipse Parameter

It’s important to extract target points center from image in computer vision quickly and accurately. The center extract with the raw gradient information in the neighborhood of the target points boundary to get the parameters of the ellipse, avoids the intermediate stage of precisely extracting individual edge points. Moreover, under the dual space representation, the ellipse parameter can easily be calculated from the dual conic with the qualification of the ellipse, and the ellipse center will be got at the same time. Then, the RANSAC algorithm is used to match the pair of corresponding points between the calibration image and the calibration plate. The experiment and application result shows that the method is efficiently.

Efficiency, Sufficiency, and Optimality

2017 ◽  
Author(s):  
Amos Golan
Keyword(s):  
Limit Theorem ◽  
Computational Efficiency ◽  
The Other ◽  
Information Compression ◽  
Information Theoretic ◽  
Conditional Limit Theorem ◽  
Concept Of Information ◽  
Conditional Limit

In this chapter I provide additional rationalization for using the info-metrics framework. This time the justifications are in terms of the statistical, mathematical, and information-theoretic properties of the formalism. Specifically, in this chapter I discuss optimality, statistical and computational efficiency, sufficiency, the concentration theorem, the conditional limit theorem, and the concept of information compression. These properties, together with the other properties and measures developed in earlier chapters, provide logical, mathematical, and statistical justifications for employing the info-metrics framework.

scholarly journals Non-Destructive Monitoring of P. fluorescens and S. epidermidis Biofilm under Different Media by Fourier Transform Infrared Spectroscopy and Other Corroborative Techniques

Coatings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 930
Author(s):  
Marco Consumi ◽  
Kamila Jankowska ◽  
Gemma Leone ◽  
Claudio Rossi ◽  
Alessio Pardini ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Early Stage ◽  
Deionized Water ◽  
The Other ◽  
Ftir Technique ◽  
Low Sensitivity ◽  
Non Destructive ◽  
Peculiar Behavior

In the present study, the early stage of bacteria biofilm formation has been studied as a function of different nutrients. Infrared spectra of Pseudomonas fluorescens (PF) and Staphylococcus epidermidis (SE), on germanium ATR crystal, were collected under deionized water H2O, phosphate buffered solution (PBS) and PBS with glucose (PBS-G). In H2O, protein bands of PF increased while, no difference in PBS and PBS-G were observed until 135 min. SE strain showed a low sensitivity to PBS composition starting to expose proteins on surfaces after 120 min. SE shows a low polysaccharides increase in H2O while, in bare and enriched PBS their intensity increases after 120 and 75 min. in PBS and PBS-G respectively. PF exhibits a peculiar behavior in H2O where the saccharide bands increased strongly after 100 min, while under all the other conditions, the intensity of polysaccharide bands increased up to the plateau probably because the layer of the biofilm exceeded the penetration capability of FTIR technique. All data suggest that, under lack of nutrients, both the bacteria tend to firmly anchor themselves to the support using proteins.

Computing Schemes for Longitudinal Train Dynamics: Sequential, Parallel and Hybrid

2015 ◽  
Vol 10 (6) ◽  
Author(s):  
Qing Wu ◽  
Colin Cole
Keyword(s):  
Parallel Computing ◽  
Personal Computer ◽  
Computational Efficiency ◽  
Computing Time ◽  
The Other ◽  
Hybrid Scheme ◽  
Sequential Scheme ◽  
Parallel Scheme ◽  
Train Dynamics

Conventionally, force elements in longitudinal train dynamics (LTD) are determined sequentially. Actually, all these force elements are independent from each other, i.e., determination of each one does not require inputs from others. This independent feature makes LTD feasible for parallel computing. A parallel scheme has been proposed and compared with the conventional sequential scheme in regard to computational efficiency. The parallel scheme is tested as not suitable for LTD; computing time of the parallel scheme is about 165% of the sequential scheme on a four-CPU personal computer (PC). A modified parallel scheme named the hybrid scheme was then proposed. The computing time of the hybrid scheme is only 70% of the sequential scheme. The other advantage of the hybrid scheme is that only two processors are required, which means the hybrid scheme can be implemented on PCs.

AUTOMATIC IMAGE REGISTRATION USING VIRTUAL CIRCLES

2004 ◽  
Vol 04 (02) ◽  
pp. 281-299
Author(s):  
HAIKEL S. ALHICHRI ◽  
MOHAMED KAMEL
Keyword(s):  
Image Registration ◽  
Linear Complexity ◽  
Image Features ◽  
Experimental Results ◽  
The Other ◽  
Distance Transform ◽  
Similarity Transformations ◽  
Edge Points ◽  
Indoor Scenes ◽  
Background Area

The main contribution of this work is a novel set of image features called the virtual circles and their use in the registration of images under similarity transformations. A virtual circle is a circle with maximal radius encompassing a background area that does not contain edge points. It has many useful properties such as its radius, and its dominant edge direction for example, which can be utilized for efficient registration. Furthermore, virtual circles are frequent and can be extracted efficiently with the help of the distance transform from many types of images. We have tested the new virtual circles method in the registration of 66 pairs of images, half of which are printed labels and the other half are indoor scenes. Experimental results have shown that this method has a linear complexity in terms of the number of pixels. It is also highly automatic, because it has a small number of parameters, which almost never need to be changed throughout the experiments.

Midbrain MRI assessments in progressive supranuclear palsy subtypes

2019 ◽  
Vol 91 (1) ◽  
pp. 98-103 ◽  
Author(s):  
Marina Picillo ◽  
Maria Francesca Tepedino ◽  
Filomena Abate ◽  
Roberto Erro ◽  
Sara Ponticorvo ◽  
...  
Keyword(s):  
Progressive Supranuclear Palsy ◽  
Clinical Diagnosis ◽  
Sensitivity And Specificity ◽  
Diagnostic Value ◽  
The Other ◽  
Class Iii ◽  
Neuroimaging Biomarkers ◽  
Low Sensitivity ◽  
Richardson’S Syndrome

ObjectivesTo explore the role of the available midbrain-based MRI morphometric assessments in (1) differentiating among progressive supranuclear palsy (PSP) subtypes (PSP Richardson’s syndrome (PSP-RS), PSP with predominant parkinsonism (PSP-P) and the other variant syndromes of PSP (vPSP)), and (2) supporting the diagnosis of PSP subtypes compared with Parkinson’s disease (PD) and healthy controls (HC).MethodsSeventy-eight patients with PSP (38 PSP-RS, 21 PSP-P and 19 vPSP), 35 PD and 38 HC were included in the present analysis. Available midbrain-based MRI morphometric assessments were calculated for all participants.ResultsCurrent MRI midbrain-based assessments do not display an adequate sensitivity and specificity profile in differentiating PSP subtypes. On the other hand, we confirmed MR Parkinsonism Index (MRPI) and pons area to midbrain area ratio (P/M) have adequate diagnostic value to support PSP-RS clinical diagnosis compared with both PD and HC, but low sensitivity and specificity profile in differentiating PSP-P from PD as well as from HC. The same measures show acceptable sensitivity and specificity profile in supporting clinical diagnosis of vPSP versus HC but not versus PD. Similar findings were detected for the newer MRPI and P/M versions.ConclusionsFurther studies are warranted to identify neuroimaging biomarkers supporting the clinical phenotypic categorisation of patients with PSP. MRPI and P/M have diagnostic value in supporting the clinical diagnosis of PSP-RS.Classification of evidenceThis study provides class III evidence that available MRI midbrain-based assessments do not have diagnostic value in differentiating the Movement Disorder Society PSP subtypes.

An efficient numerical approach for calculating the inverse kinematics for robot manipulators

Robotica ◽  
1985 ◽  
Vol 3 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Jadran Lenarčič
Keyword(s):  
Numerical Methods ◽  
Conjugate Gradient ◽  
Computational Efficiency ◽  
Execution Time ◽  
Inverse Kinematics ◽  
Robot Manipulator ◽  
Computational Procedure ◽  
Numerical Approach ◽  
The Other ◽  
Gradient Technique

SUMMARYThis paper compares three numerical methods for obtaining the joint trajectory of a robot manipulator, which causes movement along the desired Cartesian path. The first solves the kinematic equations, which are given in the Jacobian form, while the other two solve the nonlinear kinematic equations directly by using an iterative computational procedure based on the conjugate gradient technique. The computational efficiency of the proposed methods is estimated in terms of the execution time on a VAX 11/750 minicomputer. It is shown that by using the capacity of microcomputers, these methods could be well used in real-time computation.

scholarly journals Ti-in-biotite geothermometry in non-graphitic, peraluminous metapelites from Crni vrh and Resavski humovi (Central Serbia)

2009 ◽  
Vol 60 (1) ◽  
pp. 3-14 ◽  
Author(s):  
Suzana Erić ◽  
Mihovil Logar ◽  
Dragan Milovanović ◽  
Danilo Babič ◽  
Borivoj Adnađević
Keyword(s):  
Temperature Difference ◽  
The Other ◽  
Positive Correlation ◽  
Other Hand ◽  
Mineral Assemblages ◽  
Compositional Variability ◽  
Low Sensitivity

Ti-in-biotite geothermometry in non-graphitic, peraluminous metapelites from Crni vrh and Resavski humovi (Central Serbia)The study discusses the application of the Ti-in-biotite geothermometer of Henry et al. (2005) to the example of biotites from non-graphitic peraluminous micaschists of Central Serbia. Three petrographically different micaschists were distinguished on the basis of the following mineral assemblages: CV1 (St-Grt-Bt-Ms-Pg-Pl-Qtz), CV2 (Grt-St-Ky-Bt-Ms-Pl-Qtz) and RH (Grt-St-Bt-Ms-Pl-Qtz). Applying different geothermobarometers it was estimated that the studied micaschists were metamorphosed at average temperatures and pressures of 530 °C and 520 MPa (CV1incl), 580 °C and 670 MPa (CV1), 630 °C and 700 MPa (CV2) and 550 °C, 680 MPa (RH). The average temperatures obtained by the Ti-in-biotite method revealed uniform values for CV1 and CV2 micaschists and these values are very similar to the temperatures obtained by other methods. In contrast, the application of Ti-in-biotite geothermometer for RH micaschist yields the temperature difference of 85-110 °C. The variability of temperature is interpreted as a result of a positive correlation of Ti contents and XMgvalues in RH biotite, which is in disagreement with the principles of the Ti-in-biotite method. The positive Ti-XMgcorrelation is a result of the compositional variability shown by RH biotites from different samples, which can possibly be related to compositional inhomogeneities of the pelitic protolith. On the other hand, the Ti-in-biotite geothermometer for CV2 biotite gave very uniform temperatures despite variable Ti contents (Ti = 0.260, sd = 0.018 apfu). This is explained as result of the low sensitivity of Ti-in-biotite geothermometer for high Ti concentrations (> 0.25 apfu).

scholarly journals Antibodies of Toxoplasma gondii

1963 ◽  
Vol 61 (1) ◽  
pp. 53-60 ◽  
Author(s):  
D. G. Fleck
Keyword(s):  
Toxoplasma Gondii ◽  
False Positive ◽  
Double Diffusion ◽  
The Other ◽  
Low Density ◽  
High Concentration ◽  
Precipitation Line ◽  
Large Numbers ◽  
Low Sensitivity ◽  
Test Serum

1. That the number of toxoplasma organisms in the dye test affects the titre of the test serum is confirmed.2. Evidence is presented that the toxoplasma cytoplasm-modifying substance present in the peritoneal exudate of mice injected with large numbers of toxoplasma organisms more than 3 days previously is probably antibody.3. Various chemicals including detergents were capable, in high concentration, of producing a false positive dye test.4. Evidence is presented that there are two complement-fixing antigens, one with a low sensitivity and a low density, the other with a high density and a sensitivity close to that of the dye test. Heating the heavy antigen to 56° C. for 1 hr. removes most of its anticomplementary effects without altering its complement-fixing activity.5. The light antigen mentioned above was capable of producing a precipitation line in agar double-diffusion experiments, but did not inhibit dye-test antibody when mixed with an equal volume of antiserum in the dye test.6. The heavy antigen inhibited dye test antibody when mixed with an equal volume of antiserum in the dye test.

scholarly journals WILLIS METHOD MODIFICATION WITH A VIEW TO IMPROVING ROUTINE COPROPARASITOLOGICAL DIAGNOSIS

2019 ◽  
Vol 48 (1) ◽  
pp. 25-34
Author(s):  
Matheus Diniz Gonçalves Coêlho ◽  
Aryadne Gonçalves de Faria ◽  
Lucas Tobias Rodrigues Maciel ◽  
Francine Alves da Silva-Coêlho
Keyword(s):  
Intestinal Parasites ◽  
The Other ◽  
Health Staff ◽  
Routine Practice ◽  
High Morbidity ◽  
Low Density ◽  
Modified Method ◽  
Clinical Laboratories ◽  
Highly Sensitive ◽  
Low Sensitivity

Intestinal parasites still cause high morbidity and mortality, due to poor hygiene and sanitaryconditions, and therefore indiscriminate treatment has been routine practice advocated by thePublic Health staff. Although there is a consensus regarding the need to diagnose such diseases,this is not performed with the necessary care, due to great demand and the lack of a wide rangedand highly sensitive technique. In this sense, most clinical laboratories use routine methods forfecal examination such as the Lutz sedimentation or modified Ritchie methods, which are completeand easy to execute, but do not have adequate sensitivity to detect low density eggs and protozoancysts, especially when there is a predominance of low parasite burdens. In contrast, there aremethods that are based on the flotation of low density developmental forms, namely, the Willismethod (NaCl flotation d=1.120), which is rapid, easy to perform and allows high density eggflotation but with low sensitivity for protozoan cysts; and the Faust method, which is based oncentrifugal flotation of developmental forms in a 33% ZnSO4 (d=1.200) solution, but with thedisadvantage of being lengthy and requiring a centrifuge. In this study, we verified the applicabilityof introducing an alteration in the Willis method, which consisted in the substitution of NaCl byZnSO4 in order to combine the advantages of this method with the Faust method. 208 samples wereassessed by the Willis and Ritchie methods and by the proposed method (modified Willis). Thelatter proved superior to the other two (ρ <0,0001 – X2) regarding the detection of protozoan cysts,but similar to the Ritchie method in regard to other diagnosed parasites, therefore demonstratingthe high potential for the introduction of this modified method in the routine of fecal diagnosis.

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