scholarly journals Curve-Based Classification Approach for Hyperspectral Dermatologic Data Processing

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 680
Author(s):  
Stig Uteng ◽  
Eduardo Quevedo ◽  
Gustavo M. Callico ◽  
Irene Castaño ◽  
Gregorio Carretero ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Skin Cancer ◽  
Hyperspectral Image ◽  
Skin Lesions ◽  
Complete Classification ◽  
The Other ◽  
Classification Procedure ◽  
Classification Approach ◽  
The Mean ◽  
Pigmented Skin Lesions

This paper shows new contributions in the detection of skin cancer, where we present the use of a customized hyperspectral system that captures images in the spectral range from 450 to 950 nm. By choosing a 7 × 7 sub-image of each channel in the hyperspectral image (HSI) and then taking the mean and standard deviation of these sub-images, we were able to make fits of the resulting curves. These fitted curves had certain characteristics, which then served as a basis of classification. The most distinct fit was for the melanoma pigmented skin lesions (PSLs), which is also the most aggressive malignant cancer. Furthermore, we were able to classify the other PSLs in malignant and benign classes. This gives us a rather complete classification method for PSLs with a novel perspective of the classification procedure by exploiting the variability of each channel in the HSI.

scholarly journals An alternative to the rejection of observations

1932 ◽  
Vol 137 (831) ◽  
pp. 78-87 ◽  
Keyword(s):  
Standard Deviation ◽  
Continuous Function ◽  
Large Deviations ◽  
Opposite Direction ◽  
Standard Error ◽  
The Other ◽  
Cause Of Error ◽  
The Mean ◽  
Normal Law ◽  
Usual Rule

1. It is widely felt that any method of rejecting observations with large deviations from the mean is open to some suspicion. Suppose that by some criterion, such as Peirce’s and Chauvenet’s, we decide to reject observations with deviations greater than 4 σ, where σ is the standard error, computed from the standard deviation by the usual rule; then we reject an observation deviating by 4·5 σ, and thereby alter the mean by about 4·5 σ/ n , where n is the number of observations, and at the same time we reduce the computed standard error. This may lead to the rejection of another observation deviating from the original mean by less than 4 σ, and if the process is repeated the mean may be shifted so much as to lead to doubt as to whether it is really sufficiently representative of the observations. In many cases, where we suspect that some abnormal cause has affected a fraction of the observations, there is a legitimate doubt as to whether it has affected a particular observation. Suppose that we have 50 observations. Then there is an even chance, according to the normal law, of a deviation exceeding 2·33 σ. But a deviation of 3 σ or more is not impossible, and if we make a mistake in rejecting it the mean of the remainder is not the most probable value. On the other hand, an observation deviating by only 2 σ may be affected by an abnormal cause of error, and then we should err in retaining it, even though no existing rule will instruct us to reject such an observation. It seems clear that the probability that a given observation has been affected by an abnormal cause of error is a continuous function of the deviation; it is never certain or impossible that it has been so affected, and a process that completely rejects certain observations, while retaining with full weight others with comparable deviations, possibly in the opposite direction, is unsatisfactory in principle.

scholarly journals Nature versus Nurture in Shallow Convection

2010 ◽  
Vol 67 (5) ◽  
pp. 1655-1666 ◽  
Author(s):  
David M. Romps ◽  
Zhiming Kuang
Keyword(s):  
Standard Deviation ◽  
The Other ◽  
Cloud Base ◽  
Shallow Convection ◽  
Eddy Simulation ◽  
Cloud Properties ◽  
Nature Versus Nurture ◽  
Large Eddy ◽  
The Mean ◽  
Single Set

Abstract Tracers are used in a large-eddy simulation of shallow convection to show that stochastic entrainment (and not cloud-base properties) determines the fate of convecting parcels. The tracers are used to diagnose the correlations between a parcel’s state above the cloud base and both the parcel’s state at the cloud base and its entrainment history. The correlation with the cloud-base state goes to zero a few hundred meters above the cloud base. On the other hand, correlations between a parcel’s state and its net entrainment are large. Evidence is found that the entrainment events may be described as a stochastic Poisson process. A parcel model is constructed with stochastic entrainment that is able to replicate the mean and standard deviation of cloud properties. Turning off cloud-base variability has little effect on the results, which suggests that stochastic mass-flux models may be initialized with a single set of properties. The success of the stochastic parcel model suggests that it holds promise as the framework for a convective parameterization.

scholarly journals Oral and Skin Lesions Among Yemeni Khat Abusers While Chewing and After Quitting：Crosse-Sectional Survey

2021 ◽  
Author(s):  
Rowida A. Albarmaqi ◽  
Yi-Qun Kuang ◽  
Yu-Ye Li ◽  
Noha Saleh Gholais
Keyword(s):  
Standard Deviation ◽  
Dental Health ◽  
Skin Lesions ◽  
Routine Practice ◽  
Cross Sectional ◽  
Khat Chewing ◽  
Skin Symptoms ◽  
Significant Difference ◽  
The Mean ◽  
Symptoms And Signs

Abstract Background: Khat chewing is a routine practice in Yemen. Associations between Khat chewing and various adverse oral-dental health conditions have been recorded, however, adverse skin health evidence is still lacking. Objective: To investigate the difference between oral and skin symptoms and signs while chewing Khat and after quitting chewing among Yemeni khat abusers. Method: A descriptive cross-sectional study was conducted on a sample of 300 Yemeni Khat ex-chewer participants in china. Khat chewing status data, a range of oral and skin symptoms and signs, and other pertinent variables were collected using self-administered questionnaires by WeChat. The mean differences between oral and skin symptoms and signs while chewing Khat and after quitting chewing were investigated using the Paired Samples t-test. Result: Of the 300 Yemeni who participated in the study, 255(85%) were men and 45(15%) were women. The oral symptoms and signs mean while chewing was 0.26, 0.022 (standard deviation [SD], whereas that after quitting chewing Khat was 0.10 (mean), 0.269 (standard deviation [SD], t (12.00), P=0.00. The skin symptoms and signs mean while chewing was 0.13, 0.28 (standard deviation [SD], whereas that after quitting chewing Khat was M=0.06, 0.21(standard deviation [SD], t (9.407), P=0.00. Conclusions: There is a statistically significant difference between the mean oral and skin symptoms and signs while chewing and after quitting, whereas long-term Khat chewing negatively affects oral and skin health.

scholarly journals Catalogue of Clusters that are Members of Superclusters

1983 ◽  
Vol 104 ◽  
pp. 185-186
Author(s):  
M. Kalinkov ◽  
K. Stavrev ◽  
I. Kuneva
Keyword(s):  
Standard Deviation ◽  
Correlation Coefficient ◽  
The Other ◽  
Clusters Of Galaxies ◽  
Number Of Clusters ◽  
Abell Clusters ◽  
The Mean ◽  
Abell Cluster ◽  
Image Position

An attempt is made to establish the membership of Abell clusters in superclusters of galaxies. The relation is used to calibrate the distances to the clusters of galaxies with two redshift estimates. One is m10, the magnitude of the ten-ranked galaxy, and the other is the “mean population,” P, defined by: where p = 40, 65, 105 … galaxies for richness groups 0, 1, 2 …, and r is the apparent radius in degrees given by: The first iteration for redshift, z1, is obtained from m10 alone: The standard deviation for Eq. (1) is 0.105, the number of clusters with known velocities is 342 and the correlation coefficient between observed and fitted values is 0.921. With zi from Eq. (1), we define Cartesian galactic coordinates Xi = Rih−1 cosBi cosLi, Yi = Rih−1 cosBi sinLi, Zi = Rih−1 sinBi for each Abell cluster, i = 1, …, 2712, where Ri is the distance to the cluster (Mpc), and Ho = 100 h km s−1 Mpc−1.

Rapid Rhino versus Merocel nasal packs in septal surgery

2011 ◽  
Vol 125 (12) ◽  
pp. 1244-1246 ◽  
Author(s):  
A Hesham ◽  
A Ghali
Keyword(s):  
Standard Deviation ◽  
Pain Score ◽  
Visual Analogue Score ◽  
Nasal Packing ◽  
The Other ◽  
Septal Surgery ◽  
Patient Tolerance ◽  
Operative Complications ◽  
The Mean

AbstractObjective:To compare Rapid Rhino and Merocel packs for nasal packing after septoplasty, in terms of patient tolerance (both with the pack in place and during removal) and post-operative complications.Materials and methods:Thirty patients (aged 18–40 years) scheduled for septoplasty were included. Following surgery, one nasal cavity was packed with Rapid Rhino and the other one with Merocel. Patients were asked to record pain levels on a visual analogue score, on both sides, with the packs in situ and during their removal the next day. After pack removal, bleeding was compared on both sides.Results:The mean ± standard deviation pain score for the Rapid Rhino pack in situ (4.17 ± 1.78) was less than that for the Merocel pack (4.73 ± 2.05), but not significantly so (p = 0.314). The mean pain score for Rapid Rhino pack removal (4.13 ± 1.76) was significantly less that that for Merocel (6.90 ± 1.67; p = 0.001). Bleeding after pack removal was significantly less for the Rapid Rhino sides compared with the Merocel sides (p <0.05).Conclusion:Rapid Rhino nasal packs are less painful and cause less bleeding, compared with Merocel packs, with no side effects. Thus, their use for nasal packing after septal surgery is recommended.

scholarly journals Nadir Correction of AIRS Radiances

2010 ◽  
Vol 27 (3) ◽  
pp. 470-480 ◽  
Author(s):  
Chee-Kiat Teo ◽  
Tieh-Yong Koh
Keyword(s):  
Water Vapor ◽  
Standard Deviation ◽  
The Other ◽  
Mean Square ◽  
Atmospheric Infrared Sounder ◽  
Limb Effect ◽  
Atmospheric Window ◽  
The Mean ◽  
Optimal Set ◽  
Atmospheric Windows

Abstract A statistical method to correct for the limb effect in off-nadir Atmospheric Infrared Sounder (AIRS) channel radiances is described, using the channel radiance itself and principal components (PCs) of the other channel radiances to account for the multicollinearity. A method of selecting an optimal set of predictors is proposed and demonstrated for one- and two-PC predictors. Validation results with a subset of AIRS channels in the spectral region 649–2664 cm−1 show that the mean nadir-corrected brightness temperature (BT) is largely independent of scan angle. More than 66% of the channels have a root-mean-square (rms) bias less than 0.10 K after nadir correction. Limb effect on the standard deviation (SD) of BT is discernible at larger scan angles, mainly for the atmospheric windows and the water vapor channels around 6.7 μm. After nadir correction, nearly all atmospheric window channels unaffected by solar glint and more than 76% of water vapor channels examined have BT SDs brought closer to nadir values. For the window channels affected by solar glint (wavenumber &gt; 2490 cm−1), BT SDs at the scan angles with the strongest impact from solar reflection were improved on average by more than 0.6 K after nadir correction.

scholarly journals Prevalencia de síndrome de burnout en los estudiantes de la Carrera de Enfermería de la Universidad Central del Ecuador

2020 ◽  
Vol 4 (8) ◽  
pp. 38-54
Author(s):  
Luzmila De Jesús Carvajal Andrade ◽  
◽  
Belén del Rocío Logacho Villacís ◽  
Ramiro Rogelio Rojas Jaramillo ◽  
◽  
...  
Keyword(s):  
Standard Deviation ◽  
Confidence Interval ◽  
Key Words ◽  
Nursing School ◽  
The Other ◽  
Burnout Syndrome ◽  
Information Analysis ◽  
Academic Burnout ◽  
Upper Limit ◽  
The Mean

This research has been conducted in order to determine the Prevalence of the burnout syndrome among students from third to eighth semester who are attending the Nursing School. It was a prevalence study; the data were collected using the survey’s technique, in a questionnaire divided in five sections applied to 172 students. The information analysis was calculated using the Mean method and the Standard Deviation for the Academic burnout, while for the Labor burnout it was utilized the punctuation of: high, medium and low scales. The outcome results showed that the prevalence of the burnout Syndrome in both academic and labor was low. The 2.3 % of students had the Academic burnout, (Confidence interval: 95%, lower limit: 0.44% and upper limit: 4.21%) with a probability of 3.52%, on the other hand the Labor burnout was of 4% among students in the shifting internship, with a probability of 1.22%. Key words: Syndrome burnout, Stress, nursing.

scholarly journals On The Estimation of Means and Variances In The Case Of Unequal Components

1975 ◽  
Vol 8 (3) ◽  
pp. 323-335 ◽  
Author(s):  
Esa Hovinen
Keyword(s):  
Standard Deviation ◽  
The Other ◽  
Insurance Companies ◽  
Loss Ratio ◽  
Weighted Mean ◽  
The Mean ◽  
Image Position ◽  
Statistical Work ◽  
Better Than

In practical statistical work one frequently meets certain problems. For instance, we may have the following data about loss ratios in certain insurance companies and corresponding, numbers of insurance in force:I assume further that we have no reason to believe that the companies, their loss ratios and their structure of insurances in force differ in any other way than by the size of companies. The problem is how to get quick estimates of mean losses and their variances in different companies?A straitforward way to estimate the mean loss ratio would be to compute the usual mean of numbers pi, (Σpi/6) = 14; its standard deviation is 6,5. As this procedure of the “first statistician” seems to be too simple and naive, a “more cautious” statistician would compute the weighted mean loss ratioThe “more cautious” statistician would arque that his result is much better than the other result 14. But what would be the variance of the estimate 7,1, and what is the variance in the different companies?

Detection and Classification of Skin Lesions using Probability Map-based Region Growing with BA-KNN Classifier (Preprint)

2021 ◽  
Author(s):  
Sivaraj S ◽  
Dr.R. Malmathanraj
Keyword(s):  
Skin Lesion ◽  
Region Growing ◽  
Skin Lesions ◽  
Classification Approach ◽  
Probability Map ◽  
Knn Classifier ◽  
Knn Classification ◽  
Pigmented Skin Lesions ◽  
Thresholding Algorithm

BACKGROUND Melanoma is one of the most hazardous existing diseases, and is a kind of threatening pigmented skin lesion. Appropriate automated diagnosis of skin lesions and the categorization of melanoma may be exceptionally enhancing premature identification of melanomas. OBJECTIVE However, Models of categorization based on deterministic skin lesion may influence multi-dimensional nonlinear problem provokes inaccurate and ineffective categorization. This research presents a novel hybrid BA-KNN classification approach for pigmented skin lesions in dermoscopy images. METHODS In the first step, the skin lesion is preprocessed via automatic preprocessing algorithm together with a fusion hair detection and removal strategy. Also, a new probability map based region growing and optimal thresholding algorithm is integrated in this system to enhance the rate of accuracy. RESULTS Moreover, to attain better efficacy, an estimate of ABCD as well as geometric features are considered during the feature extraction to describe the malignancy of the lesion. CONCLUSIONS The evaluation of the experiment reveals the efficiency of the proposed approach on dermoscopy images with better accuracy

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