Determination of radiographic screen-film system characteristic curve and its gradient by use of a curve-smoothing technique

1978 ◽  
Vol 5 (5) ◽  
pp. 443-447 ◽  
Author(s):  
Heang-Ping Chan ◽  
Kunio Doi
Keyword(s):  
Characteristic Curve ◽  
Film System ◽  
Smoothing Technique ◽  
System Characteristic ◽  
Curve Smoothing

scholarly journals Deep Learning Based HPV Status Prediction for Oropharyngeal Cancer Patients

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 786
Author(s):  
Daniel M. Lang ◽  
Jan C. Peeken ◽  
Stephanie E. Combs ◽  
Jan J. Wilkens ◽  
Stefan Bartzsch
Keyword(s):  
Deep Learning ◽  
Cancer Patients ◽  
Oropharyngeal Cancer ◽  
Characteristic Curve ◽  
Learning Models ◽  
Convolutional Network ◽  
Hpv Status ◽  
3D Information ◽  
External Test

Infection with the human papillomavirus (HPV) has been identified as a major risk factor for oropharyngeal cancer (OPC). HPV-related OPCs have been shown to be more radiosensitive and to have a reduced risk for cancer related death. Hence, the histological determination of HPV status of cancer patients depicts an essential diagnostic factor. We investigated the ability of deep learning models for imaging based HPV status detection. To overcome the problem of small medical datasets, we used a transfer learning approach. A 3D convolutional network pre-trained on sports video clips was fine-tuned, such that full 3D information in the CT images could be exploited. The video pre-trained model was able to differentiate HPV-positive from HPV-negative cases, with an area under the receiver operating characteristic curve (AUC) of 0.81 for an external test set. In comparison to a 3D convolutional neural network (CNN) trained from scratch and a 2D architecture pre-trained on ImageNet, the video pre-trained model performed best. Deep learning models are capable of CT image-based HPV status determination. Video based pre-training has the ability to improve training for 3D medical data, but further studies are needed for verification.

DRYING OF PARTICULATE SOLIDS: DETERMINATION OF THE CHARACTERISTIC CURVE OF BROWN COAL.

1993 ◽  
Vol 11 (3) ◽  
pp. 555-570 ◽  
Author(s):  
J.L. Bueno ◽  
O. Iglesias ◽  
A. Garcia
Keyword(s):  
Brown Coal ◽  
Characteristic Curve ◽  
Particulate Solids

A Rapid Method for the Determination of Principal Stresses Across Sections of Symmetry From Photoelastic Data

1938 ◽  
Vol 5 (1) ◽  
pp. A24-A28
Author(s):  
M. M. Frocht
Keyword(s):  
Free Boundary ◽  
Rapid Method ◽  
Circular Hole ◽  
Characteristic Curve ◽  
Principal Stresses ◽  
Recent Improvement ◽  
Tangential Stresses ◽  
Circular Holes ◽  
Photoelastic Data

Abstract The author discusses: (a) Mesnager’s theorem of isoclinics, (b) the characteristic curve of tangential stresses across a section of symmetry, (c) a formula for the maximum tangential stresses for the case of a central circular hole between fields of pure tension, (d) the slope of the p curve at a point corresponding to a cupic point, (e) recent improvement in the determination of free boundary stresses, and (f) formulas for the position of cupic points for two cases. A new method for the determination of the principal stresses across sections of symmetry from photoelastic data is illustrated with three examples: (1) Bars in tension or compression with central circular holes, (2) grooved beams in bending, and (3) rings or disks with circular central holes subjected to two concentrated diametral loads.

Determination of a Suitable Moment for Formwork Removal from a Concrete Structure Using Rebound Hammer Test Methods

2021 ◽  
Vol 322 ◽  
pp. 23-27
Author(s):  
Petr Misák ◽  
Dalibor Kocáb ◽  
Petr Cikrle
Keyword(s):  
Compressive Strength ◽  
Characteristic Curve ◽  
Test Methods ◽  
Rebound Hammer ◽  
Practical Applications ◽  
Relevant Topic ◽  
Compressive Strength Of Concrete ◽  
The Moment ◽  
Non Destructive

Determining the compressive strength of concrete in the early stages of ageing has been an increasingly relevant topic in recent years, particularly with regard to the safe removal of formwork from a structure or its part. The compressive strength of concrete which designates safe removal of formwork without damaging the structure can be referred to as "stripping strength". It is undoubtedly beneficial to be able to determine the moment of safe formwork removal in a non-destructive manner, i.e. without compromising the structure. Modern rebound hammer test methods seem to be a suitable instrument with which it is possible to reduce the length of technological breaks associated with concrete ageing to a minimum, and consequently, reduce the total cost of the construction. However, the use of these methods presents a number of challenges. As many conducted experiments have shown, there is no single conversion relationship (regression model) between non-destructive rebound hammer test methods and compressive strength. It is therefore advisable to always create a unique conversion relationship for each individual concrete. In addition, it must be noted that conventional regression analysis methods operate with 50% reliability. In construction testing, however, the most common is the so-called characteristic value, which is defined as a 5% quantile. This value is therefore determined with 95% reliability. This paper describes the construction of a so-called "characteristic curve", which can be used to estimate the compressive strength of concrete in a structure using rebound hammer test methods with 95% reliability. Consequently, the values obtained from the characteristic curve can be easily used for practical applications.

scholarly journals Nephelometric determination of carbohydrate deficient transferrin

1996 ◽  
Vol 42 (4) ◽  
pp. 551-557 ◽  
Author(s):  
F Schellenberg ◽  
M Martin ◽  
E Cacès ◽  
J Y Bénard ◽  
J Weill
Keyword(s):  
Sialic Acid ◽  
Characteristic Curve ◽  
Anion Exchange Chromatography ◽  
Receiver Operator Characteristic Curve ◽  
Exchange Chromatography ◽  
Treatment Center ◽  
Serum Transferrin ◽  
Receiver Operator Characteristic ◽  
Carbohydrate Deficient Transferrin

Abstract We describe a technique for measuring carbohydrate-deficient transferrin (CDT) in serum. Serum transferrin fractions are separated by anion-exchange chromatography on microcolumns. Sialic acid-deficient transferrin fractions are collected in the eluate, and transferrin is then quantified by a rate-nephelometric technique. Imprecision (CV) was 4-5% within-run and 7-9% between runs (n = 15). Comparison with an isoelectric focusing-immunofixation method for transferrin index (x) yielded y = 761x + 7, Sy/x = 39 mg/L. Assay of sera from 90 abstainers or moderate consumers of alcohol showed that 81 (90%) had CDT concentrations between 30 and 70 mg/L. Among 74 alcoholics admitted to an alcohol treatment center, 54 (73%) had CDT > 70 mg/L, i.e., the diagnostic sensitivity was 73% at a specificity of 90% (area under receiver-operator characteristic curve = 0.891).

Stress and Adhesion Determination of a Wedged Iron Film System by Buckle Morphologies

2012 ◽  
Vol 457-458 ◽  
pp. 113-117
Author(s):  
Hong Zhou ◽  
Sen Jiang Yu ◽  
Yong Ju Zhang ◽  
Miao Gen Chen
Keyword(s):  
Magnetron Sputtering ◽  
Film Thickness ◽  
Glass Substrate ◽  
Silicone Oil ◽  
Adhesion Energy ◽  
Iron Film ◽  
Film System ◽  
Dc Magnetron Sputtering ◽  
Very High

By using the mobile property of silicone oil, a wedged iron (Fe) film system, deposited on glass substrate, has been prepared by dc-magnetron sputtering technique. The wedged Fe film is quenched by the silicone oil during deposition, and therefore contains a very high compressive stress, which is relieved by formation of a large number of telephone cord buckles. Both the buckle width l and maximum buckle deflection δ increase linearly with the film thickness, but the ratio of δ to l (l/δ ) decreases steadily. The internal stress and adhesion energy are estimated in the frame of continuum elastic theory.

Intraoperative flow cytometry analysis of glioma tissue for rapid determination of tumor presence and its histopathological grade

2013 ◽  
Vol 118 (6) ◽  
pp. 1232-1238 ◽  
Author(s):  
Takahiro Shioyama ◽  
Yoshihiro Muragaki ◽  
Takashi Maruyama ◽  
Takashi Komori ◽  
Hiroshi Iseki
Keyword(s):  
Flow Cytometry ◽  
Predictive Value ◽  
Rapid Determination ◽  
Characteristic Curve ◽  
Biopsy Sample ◽  
Surgical Biopsy ◽  
Diagnostic Efficacy ◽  
Histopathological Grade ◽  
Number Of Cells

Object Intraoperative histopathological investigation plays an important role during surgery for gliomas. To facilitate the rapid characterization of resected tissue, an original technique of intraoperative flow cytometry (iFC) was established. The objective in this study was evaluation of this technique's efficacy for rapidly determining tumor presence in the surgical biopsy sample and WHO histopathological grade of the neoplasm. Methods In total, 328 separate biopsy specimens obtained during the resection of 81 intracranial gliomas were analyzed with iFC. The evaluated malignancy index (MI) was defined as the ratio of the number of cells with greater than normal DNA content to the total number of cells. The duration of iFC in all cases was approximately 10 minutes. Each sample was additionally investigated histopathologically on frozen and permanent formalin-fixed paraffin-embedded tissue sections. The latter process was used as a “gold standard” control for evaluation of the diagnostic efficacy of iFC analysis. Results The MI differed significantly between neoplastic and perilesional brain tissue (25.3% ± 22.0% vs 4.6% ± 2.6%, p < 0.01). Receiver operating characteristic curve analysis revealed a corresponding area under the curve value of 0.941. The optimal cutoff level of the MI for identification of tumor in the biopsy specimen was 6.8%, which provided 0.88 sensitivity, 0.88 specificity, 0.97 positive predictive value, 0.60 negative predictive value, and 0.88 diagnostic accuracy. Additionally, the MI showed a significant association with WHO histopathological grades of glioma (p < 0.01), but its values in Grade II, III, and IV tumors overlapped prominently and were on average 13.3% ± 11.0%, 35.0% ± 21.8%, and 46.6% ± 23.1%, respectively. Conclusions Results of this study demonstrate that iFC with the determination of the MI may be feasible for rapidly determining glioma presence in a surgical biopsy sample.

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