The use of neural networks for the prediction of the critical factor of safety of an artificial slope subjected to earthquake forces

AbstractThis study deals with the development of Artificial Neural Network (ANN) and Multiple Regression (MR) models for estimating the critical factor of safety (Fs) value of a typical artificial slope subjected to earthquake forces. To achieve this, while the geometry of the slope and the properties of the man-made soil are kept constant, the natural subsoil properties, namely, cohesion, internal angle of friction, the bulk unit weight of the layer beneath the ground surface and the seismic coefficient, varied during slope stability analyses. Then, the Fs values of this slope were calculated using the simplified Bishop method, and the minimum (critical) Fs value for each case was determined and used in the development of the ANN and MR models. The results obtained from the models were compared with those obtained from the calculations. Moreover, several performance indices, such as determination coefficient, variance account for, mean absolute error and root mean square error, were calculated to check the prediction capacity of the models developed. The obtained indices make it clear that the ANN model has shown a higher prediction performance than the MR model

Moving object detection using adaptive subband decomposition and fractional lower order statistics in video sequences

Cataloged from PDF version of article.In this paper, a moving object detection method in video sequences is described. In the 3rst step, the camera motion is eliminated using motion compensation. An adaptive subband decomposition structure is then used to analyze the motion compensated image. In the “low–high” and “high–low” subimages moving objects appear as outliers and they are detected using a statistical detection test based on fractional lower-order statistics. It turns out that the distribution of the subimage pixels is almost Gaussian in general. On the other hand, at the object boundaries the distribution of the pixels in the subimages deviates from Gaussianity due to the existence of outliers. By detecting the regions containing outliers the boundaries of the moving objects are estimated. Simulation examples are presented. (C) 2002 Elsevier Science B.V. All rights reserved

Adaptive methods for dithering color images

Cataloged from PDF version of article.Most color image printing and display devices do not have the capability of reproducing true color images. A common remedy is the use of dithering techniques that take advantage of the lower sensitivity of the eye to spatial resolution and exchange higher color resolution with lower spatial resolution. In this paper, an adaptive error diffusion method for color images is presented. The error diffusion filter coefficients are updated by a normalized least mean square-type (LMS-type) algorithm to prevent textural contours, color impulses, and color shifts, which are among the most common side effects of the standard dithering algorithms. Another novelty of the new method is its vector character: Previous applications of error diffusion have treated the individual color components of an image separately. Here, we develop a general vector approach and demonstrate through simulation studies that superior results are achieved. © 1997 IEEE

Robust direction of arrival estimation in non-Gaussian noise

Cataloged from PDF version of article.In this correspondence, a nonlinearly weighted least-squares method is developed for robust modeling of sensor array data. Weighting functions for various observation noise scenarios are determined using maximum likelihood estimation theory. Computational complexity of the new method is comparable with the standard least-squares estimation procedures. Simulation examples of direction-of-arrival estimation are presented

QR-RLS algorithm for error diffusion of color images

Printing color images on color printers and displaying them on computer monitors requires a significant reduction of physically distinct colors, which causes degradation in image quality. An efficient method to improve the display quality of a quantized image is error diffusion, which works by distributing the previous quantization errors to neighboring pixels, exploiting the eye's averaging of colors in the neighborhood of the point of interest. This creates the illusion of more colors. A new error diffusion method is presented in which the adaptive recursive least-squares (RLS) algorithm is used. This algorithm provides local optimization of the error diffusion filter along with smoothing of the filter coefficients in a neighborhood. To improve the performance, a diagonal scan is used in processing the image, (C) 2000 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(00)00611-5]

Detection of microcalcifications in mammograms using higher order statistics

Cataloged from PDF version of article.A new method for detecting microcalcifications in mammograms is described. In this method, the mammogram image is first processed by a subband decomposition filterbank. The bandpass subimage is divided into overlapping square regions in which skewness and kurtosis as measures of the asymmetry and impulsiveness of the distribution are estimated. The detection method utilizes these two parameters. A region with high positive skewness and kurtosis is marked as a region of interest. Simulation results show that this method is successful in detecting regions with microcalcifications

Search for axions in streaming dark matter

A new search strategy for the detection of the elusive dark matter (DM) axion is proposed. The idea is based on streaming DM axions, whose flux might get temporally enormously enhanced due to gravitational lensing. This can happen if the Sun or some planet (including the Moon) is found along the direction of a DM stream propagating towards the Earth location. The experimental requirements to the axion haloscope are a wide-band performance combined with a fast axion rest mass scanning mode, which are feasible. Once both conditions have been implemented in a haloscope, the axion search can continue parasitically almost as before. Interestingly, some new DM axion detectors are operating wide-band by default. In order not to miss the actually unpredictable timing of a potential short duration signal, a network of co-ordinated axion antennae is required, preferentially distributed world-wide. The reasoning presented here for the axions applies to some degree also to any other DM candidates like the WIMPs.Comment: 5 page

Comparison of chemotherapy and hematopoietic stem cell transplantation pre and postterm DMFT scores: A preliminary study

Aims: Chemotherapy is frequently used as a conditioning regimen to destroy malignant marrow cells before transplantation. Xerostomia, dysphagia, altered taste perception, mucositis, soft‑tissue ulceration, and infection are common adverse oral effects of chemotherapy. The study was aimed to compare decayed, missing, filled teeth (DMFT) scores before and after hematopoietic stem cell transplantation (HSCT) and chemotherapy.Materials and Methods: Thirty‑six patients undergoing HSCT were included in the study. Apre‑HSCT dental treatment protocol was implemented that consisted of restoration of all active carious lesions, treatment of periodontal infections, and extraction of all teeth with advanced periodontal disease. Upon completion of dental treatment, the importance of rigorous and effective oral hygiene was reemphasized, and patients were recalled 6 months later. DMFT scores were calculated prior to the initiation of HSCT treatment and 6 months after transplantation.Statistical Analysis Used: Regression analysis was used to evaluate the effects of HSCT and chemotherapy on DMFT scores.Results: Wilcoxon T test showed a statistically significant difference in DMFT scores before and after HSCT (P < 0.001). Conclusions: DMFT scores were found to increase after chemotherapy and HSCT, suggesting that the risk of infection is higher among HSCT patients when compared to other individuals. The results emphasize the need for dental examinations as an integral part of examination and treatment planning for patients undergoing HSCT and chemotherapy.Key words: Chemotherapy, decayed missing filled teeth scores, hematopoietic stem cell transplantatio

Critical Micronutrients in Pregnancy, Lactation, and Infancy: Considerations on Vitamin D, Folic Acid, and Iron, and Priorities for Future Research

The Early Nutrition Academy and the European Commission-funded EURRECA Network of Excellence jointly sponsored a scientific workshop on critical micronutrients in pregnancy, lactation, and infancy. Current knowledge and unresolved questions on the supply of vitamin D, folic acid, and iron for pregnant women, lactating women, and infants, and their health effects were discussed. The question was addressed of whether, and under which circumstances, supplementation with these micronutrients in addition to usual dietary intakes is advisable. The workshop participants concluded that public health strategies for improving supplementation with these micronutrients in pregnancy, lactation, and infancy are required. Further research priorities should focus on adequately powered human intervention trials to obtain a stronger evidence base for the amounts of vitamin D, folic acid, and iron that have optimal effects on health. The conclusions of the workshop should help to inform the scientific community as well as public health policy strategies. Copyright (C) 2011 S. Karger AG, Base

Video fire detection - Review

Cataloged from PDF version of article.This is a review article describing the recent developments in Video based Fire Detection (VFD). Video surveillance cameras and computer vision methods are widely used in many security applications. It is also possible to use security cameras and special purpose infrared surveillance cameras for fire detection. This requires intelligent video processing techniques for detection and analysis of uncontrolled fire behavior. VFD may help reduce the detection time compared to the currently available sensors in both indoors and outdoors because cameras can monitor “volumes” and do not have transport delay that the traditional “point” sensors suffer from. It is possible to cover an area of 100 km2 using a single pan-tiltzoom camera placed on a hilltop for wildfire detection. Another benefit of the VFD systems is that they can provide crucial information about the size and growth of the fire, direction of smoke propagation. © 2013 Elsevier Inc. All rights reserve