Horizontal Edges Research Articles

All one-term tight descriptions of 3-paths in normal plane maps without [formula omitted

A description of paths on three vertices (3-paths) in normal plane maps (NPMs) is tight if no parameter of this description can be improved and no term dropped.We know that there are precisely seven tight descriptions of 3-paths in triangle-free NPMs: {(5,3,6),(4,3,7)}, {(3,5,3),(3,4,4)}, {(5,3,6),(3,4,3)}, {(3,5,3),(4,3,4)}, (5,3,7), (3,5,4), and (5,4,6).The problem of describing all tight descriptions of 3-paths in arbitrary NPMs is widely open. It is only known that there are precisely three tight descriptions consisting of one triplet of restrictions on the vertex degrees of 3-paths: (5,∞,6), (5,10,∞), or (10,5,∞).If NPMs are allowed to have K4−e as subgraphs, then it can happen that every 3-path goes through a vertex of unbounded degree: for example, we delete every other horizontal edge from a double 2n-pyramid. This fact explains the appearance of ∞ in the above description.The purpose of this paper is to prove that there are precisely four tight one-term descriptions of 3-paths in normal plane maps without K4−e: (10,5,20), (10,6,15), (5,10,15), and (5,15,6). In particular, the same description holds for 3-polytopes.

First- and second-order contributions to depth perception in anti-correlated random dot stereograms

The binocular energy model of neural responses predicts that depth from binocular disparity might be perceived in the reversed direction when the contrast of dots presented to one eye is reversed. While reversed-depth has been found using anti-correlated random-dot stereograms (ACRDS) the findings are inconsistent across studies. The mixed findings may be accounted for by the presence of a gap between the target and surround, or as a result of overlap of dots around the vertical edges of the stimuli. To test this, we assessed whether (1) the gap size (0, 19.2 or 38.4 arc min) (2) the correlation of dots or (3) the border orientation (circular target, or horizontal or vertical edge) affected the perception of depth. Reversed-depth from ACRDS (circular no-gap condition) was seen by a minority of participants, but this effect reduced as the gap size increased. Depth was mostly perceived in the correct direction for ACRDS edge stimuli, with the effect increasing with the gap size. The inconsistency across conditions can be accounted for by the relative reliability of first- and second-order depth detection mechanisms, and the coarse spatial resolution of the latter.

Evidence for chromatic edge detectors in human vision using classification images.

Edge detection plays an important role in human vision, and although it is clear that there are luminance edge detectors, it is not known whether there are chromatic edge detectors as well. We showed observers a horizontal edge blurred by a Gaussian filter (with widths of σ = 0.1125, 0.225, or 0.45°) embedded in blurred Brown noise. Observers had to choose which of two stimuli contained the edge. Brown noise was used in preference to white noise to reveal localized edge detectors. Edges and noise were defined by either luminance or chromatic contrast (isoluminant L/M and S-cone opponent). Classification image analysis was applied to observer responses. In this analysis, the random components of the stimulus are correlated with observer responses to reveal a template that shows how observers weighted different parts of the stimulus to arrive at their decision. We found classification images for both luminance and isoluminant chromatic stimuli that had shapes very similar to derivatives of Gaussian filters. The widths of these classification images tracked the widths of the edges, but the chromatic edge classification images were wider than the luminance ones. These results are consistent with edge detection filters sensitive to luminance contrast and isoluminant chromatic contrast.

Three sides supported unreinforced masonry walls under multi-directional loading

Interaction curves for masonry walls supported on all four edges subject to multi-directional loading has recently been reported by the authors (Noor-E-Khuda et al., 2018). Load bearing URM walls are generally detailed with vertical control joints (which are structural end where the normal stress vanishes), and non-load bearing walls are likely to have unsupported top horizontal edge. Therefore, three sides supported URM walls are examined in this study. An explicit finite element macro model based on a layered shell element is used in the investigation. A series of interaction curves approximately resembling bilinear domain is developed to represent the response of the one vertical edge unsupported URM walls under multi-directional loading. The interaction curves for the top horizontal edge free walls showed a trilinear approximation. Influence of the boundary conditions and the level of out-of-plane loading to the shape of the interaction curve have been examined. It is shown that the in-plane capacity reduces rapidly beyond a critical out-of-plane load level; therefore, disregarding the multi-directional loading interaction could be unsafe. A simplified non-dimensional expression proposed by the authors for the interaction curves of four sides supported walls is extended for the three sides supported walls in this paper.

Ground motions around a deep semielliptic canyon with a horizontal edge subjected to incident plane SH waves

We study scattering of antiplane shear waves induced by a deep semielliptic canyon with a horizontal edge. We employ the region-point-matching technique to cope with the problem considered. Through an auxiliary boundary, a part of the circumference of a semiellipse, the whole analyzed region is divided into two subregions. We express the displacement fields in terms of Mathieu functions. We unify two distinct elliptic coordinates via a simple coordinate transformation relation. Integration of the coordinate transformation relation into the region-point-matching technique simplifies the procedure for constructing simultaneous equations. Imposing the continuity conditions and traction-free ones, we obtain the expansion coefficients. Frequency-domain results demonstrate ground motion variability based on several key factors. Ground surface responses under seismic shaking are also simulated in the time domain.

A Study on Real-Time Detection Method of Lane and Vehicle for Lane Change Assistant System Using Vision System on Highway

In this work, we introduce an approach to detect information about lane and vehicle for the driver assistance system, or the lane change assistant system. Most previous research works could only detect the lanes or vehicles separately. However, the combination of lane information and vehicle information is able to support the driver assistance system, or the lane change assistant system, and to improve the reliability of results. For the lane change assistant system (LCAS), it must detect the frontal lanes and discover the vehicles around a test vehicle. Therefore, in this study, a vision system is utilized including three cameras, two of them are under the right and left wing mirrors, the left one is equipped on the windscreen of the test vehicle. The images from the cameras are used to detect three lanes, and detect vehicles. In the lane detection, the line detection is used. For the vehicle detection, we combine the horizontal edge filter,the Otsu’s thresholding, and the vertical edge. The horizontal edge filter and the Otsu’s thresholding are used to detect the vehicle candidates, then the vertical edge is used to verify the vehicle candidates.Moreover, Kalman filter is used to track the detected vehicle. Finally, the relative speed between the detected vehicle and the test is computed in this work. The proposed algorithm works in an average of 43 ms for each frame with resolution on a 3.30 GHz Intel CPU. The system was tested on the highway in Korea.

Multi‐directional colour edge detector using LQS convolution

A new linear colour image filter based on linear quaternion systems (LQSs) is introduced. It detects horizontal, vertical, left- and right-diagonal edges with a single LQS convolution mask. The proposed filter is a canonic minimal filter of four LQS filters, each with different angles of rotation combined parallel wise. Different angles of rotation are a key features of the new filter such that horizontal, vertical, left, and right-diagonal LQS filter masks rotate pixels through angles , , , and , respectively. Although, the four LQS masks are combined parallel to make a single LQS mask but derived using four quaternion convolutions, one for each direction of edges, the LQS filter produces a result without the combination of results from four separate edge detectors. This methodology could be generalised to design more elaborate LQS filters to perform other geometric operations on colour image pixels. The proposed filter translates smoothly changing colours to different shades of grey and produces coloured edges in multiple directions, where there is a sudden change of colour in the original image. Another key idea of the proposed filter is that it is linear because it operates in homogeneous coordinates.

Trap deployment along linear transects perpendicular to forest edges: impact on capture of longhorned beetles (Coleoptera: Cerambycidae)

Forests provide important ecosystem services, and the need for these services is expected to increase. Although disturbances are often important components of management plans for forest ecosystems, management efforts often target the prevention and mitigation of disturbances that threaten these services. Exotic insects are an increasingly important disturbance agent in terms of ecological and economic impacts, particularly large woodborers in the family Cerambycidae. Semiochemical-baited traps are important components of management programs. This study looked at the effect of trap location along a horizontal edge—forest gradient with traps deployed in forest clearings adjacent to forests, at the forest—clearing edge and in the forest. Nine species were captured in high enough numbers for analysis, and significant effects of trap location relative to the edge were observed in all but one. Three patterns of edge effects were observed. In general, Acmaeops proteus proteus (Kirby) was more abundant at the edge than in the forest interior; male and female Monochamus mutator LeConte and Monochamus scutellatus (Say) were more abundant in the clearing adjacent to the forest than in the forest; and Anelaphus pumilus (Newman), Euderces pini (Fabricius), Neoclytus acuminatus (Fabricius), male and female Monochamus carolinensis (Olivier) and female Monochamus titillator (Fabricius) were more abundant in the forest than the adjacent clearing. These results demonstrate that non-targeted surveys for Cerambycidae should deploy traps in multiple locations along the forest edge-interior gradient and that taxa-specific surveys should be developed based on knowledge of how this gradient impacts trap performance.

Edge information diffusion based reconstruction (EIDR) for cone beam computed laminography.

Computed laminography (CL) is a prospective nondestructive testing technique for flat object inspection in industrial applications. However, CL image reconstruction is a challenging task because incomplete projection data are acquired from the CL scan. When a conventional computed tomography (CT) reconstruction method is applied to cone beam CL data, the vertical edges (singularities in the z-direction) in the reconstructed image would be blurred. On the contrary, the horizontal edges (singularities within slices) can be quite accurately reconstructed. Based on this key observation, an edge information diffusion method is developed, which fixes the horizontal edges and propagates their values within the slices. An effective CL reconstruction method is then proposed for flat object inspection by combining the edge information diffusion procedure, which plays the role of regularization, with conventional CT image reconstruction algorithms. Experiments on both simulated data and real data are performed to verify the effectiveness of the proposed method. The results show that the proposed method can effectively suppress the inter-slice aliasing and blurring caused by incompleteness of the CL scan data, and that it outperforms other state-of-the-art methods.

A study on obstacle detection method of the frontal view using a camera on highway

In this work, we introduce an approach to detect vehicles for driver assistance, or warning system. For driver assistance system, it must detect both lanes (left and right side lane), and discover vehicles ahead of the test vehicle. Therefore, in this study, we use a camera, it is installed on the windscreen of the test vehicle. Images from the camera are used to detect three lanes, and detect multiple vehicles. In lane detection, line detection and vanishing point estimation are used. For the vehicle detection, we combine the horizontal and vertical edge detection, the horizontal edge is used to detect the vehicle candidates, and then the vertical edge detection is used to verify the vehicle candidates. The proposed algorithm works with of 480 × 640 image frame resolution. The system was tested on the highway in Korea.

Square texton histogram features for image retrieval

A new image feature descriptor for content-based image retrieval is proposed, named as Square Texton Histogram (STH). STH is derived based on the correlation between texture orientation and color information. Based on julesz’s texton theory ‘Square Texton’ templates are proposed for Image texture analysis. Texture Orientation is computed by using proposed multi texture orientation detector that incorporates horizontal, vertical and diagonal edges information. Features are extracted by correlating texture color and edge orientation by using 4-directional co-occurrence matrix while; the final set of features is obtained by histogram. To find similarity between query and target image, a weighted square-chord distance measure is proposed. The Proposed distance metric integrates the advantages of both bin-by-bin and weighted distance metrics. The proposed STH method is tested on standard dataset’s that are extensively used in CBIR domain, such as Coral5K and Coral10K. STH has good discrimination power of primary visual features.

Fast hand and finger detection algorithm for interaction on smart display

This paper presents a fast and accurate hand detection and tracking algorithm for depth images using an object contour analysis for which pairs of horizontal edges of an object are used. The computational complexity for generating the pairs of edges and estimating the object shape is low. A shape analysis is performed in the raster scan order and an object which can be a finger is selected as the finger candidate during the line scan. The initial hand is detected by searching for an object with a shape that corresponds to the predefined shape of the initial hand in the entire depth range. Thus, there is no assumption of the hand location throughout the depth, and the cluttered background has little effect on the detection. This paper also proposes a low-complexity hand tracking method which achieves 97.11% in the detection rate and 10.39 ms in the average processing time for a frame, respectively, when a single hand is detected. For five hands, the average processing time is 21.15 ms. These results show that the proposed method can be applied to the real-time application of vision-based HCI especially for smart display.

A new blind snake of the genus Letheobia (Serpentes: Typhlopidae) from Rwanda with redescriptions of L. gracilis (Sternfeld, 1910) and L. graueri (Sternfeld, 1912) and the introduction of a non-invasive preparation procedure for scanning electron microscopy in zoology.

A new species of blind snake in the genus Letheobia is described from Akagera National Park in eastern Rwanda. The new species is most similar to species of the L. gracilis complex, particularly L. gracilis and L. graueri. It differs from all other species of the genus by a unique combination of morphological characters, including the highest number of middorsal scale rows (834) and the most extreme elongation (total-length/midbody-width ratio 131) of all species in the genus and of any species of snake in the world; 22-22-22 longitudinal scale rows; snout in dorsal profile rounded, in lateral profile bluntly rounded with an angular horizontal edge ventrally; rostral broad, posteriorly rounded; eyes invisible; supralabial imbrication pattern T-0; tail short (1.3 percent of total length) with an apical spine; and a pink life colouration. The holotype of the new species was collected in gallery forest at a lake shore surrounded by savanna at 1300 m elevation. We produced scanning electron microscope images of the heads of the investigated specimens applying a liquid-substitution preparation procedure which does not require coating or drying and thus does not irreversibly damage the investigated samples. The obtained images allow an easy and more accurate examination of the scalation.

Robust Visual Tracking Based on Convolutional Features with Illumination and Occlusion Handing

Visual tracking is an important area in computer vision. How to deal with illumination and occlusion problems is a challenging issue. This paper presents a novel and efficient tracking algorithm to handle such problems. On one hand, a target’s initial appearance always has clear contour, which is light-invariant and robust to illumination change. On the other hand, features play an important role in tracking, among which convolutional features have shown favorable performance. Therefore, we adopt convolved contour features to represent the target appearance. Generally speaking, first-order derivative edge gradient operators are efficient in detecting contours by convolving them with images. Especially, the Prewitt operator is more sensitive to horizontal and vertical edges, while the Sobel operator is more sensitive to diagonal edges. Inherently, Prewitt and Sobel are complementary with each other. Technically speaking, this paper designs two groups of Prewitt and Sobel edge detectors to extract a set of complete convolutional features, which include horizontal, vertical and diagonal edges features. In the first frame, contour features are extracted from the target to construct the initial appearance model. After the analysis of experimental image with these contour features, it can be found that the bright parts often provide more useful information to describe target characteristics. Therefore, we propose a method to compare the similarity between candidate sample and our trained model only using bright pixels, which makes our tracker able to deal with partial occlusion problem. After getting the new target, in order to adapt appearance change, we propose a corresponding online strategy to incrementally update our model. Experiments show that convolutional features extracted by well-integrated Prewitt and Sobel edge detectors can be efficient enough to learn robust appearance model. Numerous experimental results on nine challenging sequences show that our proposed approach is very effective and robust in comparison with the state-of-the-art trackers.

Study on Single Camera Based ANPR System for Improvement of Vehicle Number Plate Recognition on Multi-lane Roads

In this paper, we introduce the single camera-based number recognition system used for this system recognizes vehicle number plates on one lane by using a single camera. Intelligent transport system (ITS) has been constructed because there is a limit in solving traffic problems in a physical manner such as construction of roads and subways. The single camera-based number recognition system used for this system recognizes vehicle number plates on one lane by using a single camera. Due to the increased cost of the installation and maintenance thereof, there is a growing need for a multi-lane-based number recognition system. When the single camera-based number recognition system is used for multi-lane recognition, the recognition rate is lowered due to a difference in vehicle image size among lanes and a low-resolution problem. Therefore, in this study, we applied a character extraction algorithm using connected vertical and horizontal edge segments-based labeling to improve multi-lane vehicle number recognition rate and thereby to allow application of the single camera-based system to multi-lane roads.

Comparison of edge detection algorithms for electric wire recognition

Edge detection is the preliminary step in image processing for object detection and recognition procedure. It allows to remove useless information and reduce amount of data before further analysis. The paper contains the comparison of edge detection algorithms optimized for detection of horizontal edges. For comparison purposes the algorithms were implemented in the developed application dedicated to detection of electric line wires. The optimized algorithms were benchmarked on a set of images of electric wires.

Stairways detection based on approach evaluation and vertical vanishing point

Stair region detection and distance estimation from a stair image are challenging activities to support visually impaired navigation safely in unknown environments. In this paper, a framework is proposed for detecting stair region from a stair image utilising some natural and unique property of a stair. One unique property of them is, every stair step's beginning and ending horizontal edge point intersects with two vertical edge points creating three connected point (TCP). The TCPs are used to validate the stair edge segments and calculate the vertical vanishing point to justify the stair edges. This justification ensures that validated edge segments are arranged in an increasing parallel order which is the other unique property of a stair. These increasing edge segments are verified by utilising the y coordinate value of the vanishing point and the detection of stair candidate region is confirmed by these properties. In addition, the triangular similarity is used for distance estimation from camera to stair. The proposed framework is tested using various stair images under a variety of conditions and results are presented to demonstrate the efficiency and effectiveness.

A Patent: Innovation in the Bottle and Environmental Approach for Liquid Packaging Material

Food packaging is one of the essential steps of food industry because of kinds of reasons such as hygiene, practical usage, fast and easy consumption, long shelf life, good and long preserving of foods etc. This invention related with innovation of bottle that provides preservation, storage and transport of water and similar liquid into containers. Created patent brings a new invention of bottle which has not bottle cap but can be closed easily due to its invented special design thus a patent was obtained for related industries. In the patented design, length of inlet is long in the invention of container. There are one or two register films due to preference bottom of the inlet section. Bottle contains at least two vertical folding edges those have 180o vertical angle and also have at least one or two due to preference horizontal folding edge in the inlet section. Biopolymers from renewable resources have been examined and studied with great interest in recently. Environmental plastics are made from renewable raw materials such as maize and potato starch or the patent article, patent was introduced with suggestion manufacturing designed bottle with biodegradable materials for sustainable environment.

Diffusion model of oxygen in c-axis oriented YBa2Cu3O7-δ films

The relationship between microstructure and diffusion of oxygen in YBCO films are studied in this work. The dislocation structure in magnetron sputtered c-axis oriented YBCO films deposited on (100)SrTiO3 substrates consists of vertical (//c-axis) screw dislocation forests together with layered horizontal (⊥c-axis) edge dislocation net-works. It is found that in the oxygenation process of YBCO films, oxygen diffusion is greatly enhanced by short circuit paths which we suggest to be the horizontally (⊥c-axis) layered edge dislocation net-works. Base on the structure of c-axis oriented YBCO films, the oxygen diffusion process was examined by applying the cylinder diffusion model. The diffusion coefficient of oxygen and the corresponding activation energy were measured.

Physical mechanism of centrifugal-gravity wave resonant instability in azimuthally symmetric swirling flows

A linear stability analysis on the dynamics of azimuthally symmetric swirling flows and the emergence of steady rotating polygons is presented. The different behaviors of the system are discussed as an interaction between horizontal inner centrifugal edge waves and outer vertical gravity edge waves.