Convex Edge Research Articles

Representation of Gravity-Aligned Scene Structure in Ventral Pathway Visual Cortex

The ventral visual pathway in humans and non-human primates is known to represent object information, including shape and identity [1]. Here, we show the ventral pathway also represents scene structure aligned with the gravitational reference frame in which objects move and interact. We analyzed shape tuning of recently described macaque monkey ventral pathway neurons that prefer scene-like stimuli to objects [2]. Individual neurons did not respond to a single shape class, but to a variety of scene elements that are typically aligned with gravity: large planes in the orientation range of ground surfaces under natural viewing conditions, planes in the orientation range of ceilings, and extended convex and concave edges in the orientation range of wall/floor/ceiling junctions. For a given neuron, these elements tended to share a common alignment in eye-centered coordinates. Thus, each neuron integrated information about multiple gravity-aligned structures as they would be seen from a specific eye and head orientation. This eclectic coding strategy provides only ambiguous information about individual structures but explicit information about the environmental reference frame and the orientation of gravity in egocentric coordinates. In the ventral pathway, this could support perceiving and/or predicting physical events involving objects subject to gravity, recognizing object attributes like animacy based on movement not caused by gravity, and/or stabilizing perception of the world against changes in head orientation [3-5]. Our results, like the recent discovery of object weight representation [6], imply that the ventral pathway is involved not just in recognition, but also in physical understanding of objects and scenes.

Research on five-axis flank milling of convex edge surface with a concave cutter

Convex edge surfaces are always encountered in industry, such as the leading and trailing edges of turbine blades. Concave cutter can be used to flank machine such surfaces. The fundamental theory is given by investigating the conjugation between a concave cutter and a cylindrical surface. By analyzing the projection of the grazing curve in the cross-section plane, it finds that convex edge surface with various cross-section radiuses can be machined with a concave cutter by adjusting the cutter orientation. Experimental verification is given to illustrate the proposed method. Compared to cylindrical flat-end cutter, concave cutter can improve the machining efficiency greatly.

First fossil representative of the family omalisidae (Coleoptera, Elateroidea sensu lato) from the Baltic amber

The paper describes Jantarokrama utilis Kovalev et Kirejtshuk, gen. et sp. nov., the first fossil representative of the family Omalisidae from the Upper Eocene Baltic amber, which is similar to the Recent Phaeopterus unicolor Costa, 1856, but distinguished from the latter by the larger and not so slender body, smaller distance between antennal insertions, longer antennae, wider prothorax with very convex anterior edge of the pronotum, and particularly by five completely exposed abdominal ventrites. The diagnosis of the new genus among generic taxa of Omalisidae and its similarity to Berendtimirus Winkler, 1987 (Berendtimiridae) are discussed.

J0470102 SiC薄膜のはく離強度に及ぼす界面ナノワイヤの影響

In order to evaluate the influence of nano-wires formed at interface on delamination strength of SiC films, the nano-wires were formed on high-speed steel substrates by a plasma discharging method, and the SiC film was deposited on the substrate using a sputtering apparatus. The delamination strength was evaluated using the convex edge indent method, where a diamond indenter was indented to the specimen with convex edge using a nano-indenter. The result showed that abrupt increment of the displacement of the indenter occurred at the film delamination. The interfacial fracture toughness of the specimen with the nano-wires was around three times higher than that without the nano-wires. The interfacial fracture toughness decreased with increasing normalized base area of the nano-wires due to cracking of the film.

Effect of Seed Husk, GA3, KNO3 and Seed Orientation in Seedbed on Germination Characters of White Succary Mango Seeds

This experiment was conducted in two successive seasons (2012/13 & 2013/14). Under the condition ofplastic house covered with seran. The objective was to study the effect of seed husk, GA3, KNO3 and seed orientation inseedbed on germination percentage and subsequent seedling growth of White Succary rootstock. From this study, thehighest germination percentage and germination velocity of mango seeds and standard seedling growth could beachieved through husking seeds or sowing seed in position of vertical with the convex edge upwards after soaking in tapwater (48h) or through soaking seeds in GA3 at 1000 ppm for 48h.Moreover, there was a remarkable effect of husking,GA3 and KNO3 in increasing growth of the obtained seedlings in terms of stem length and leaf number as well as thefresh and dry weights of roots.

THE GEOGRAPHICAL BACKGROUND TO THE ARRIVAL OF MAN IN AUSTRALIA AND TASMANIA

A USTRALIA and the Americas were both colonized for the first time during ?' the last Ice Age by a physically modern man, employing advanced Palaeolithic technologies. In both cases, man entered a new continent, adapting his own culture to deal with unfamiliar country, animals and plants, and conversely subjecting the environment to the ecological pressures of his own technology to which it had never before been exposed. The colonization may be seen as part of a general geographical expansion carried out by late Palaeolithic man, the move into Australia predating that into the Americas by at least 10,000 years. Their completion left the polar ice caps, and some islands of the Pacific and elsewhere, as the only significant areas of land still to be claimed. To get to America, the first colonists derived from the Gravettoid cultures of northern Eurasia, would have had to negotiate glacial or periglacial conditions, but their journey could have been carried out overland, and many of the plants and animals in the new region would have been familiar to them. Australia, however, could only have been reached by sea, the several water barriers of Wallacea (Darlington 1957 : 462) providing the shortest crossings, and the continent beyond, isolated since the early Tertiary, contained a largely endemic and highly distinctive flora and fauna. Most of the early Australian stone industries are characterized by flat convex edge, steep concave edge and high domed scrapers , with considerable regional variation. Their closest analogues are found in the late Palaeolithic Middle Stone Age industries of sub-Saharan Africa and India from which they were probably derived. The paucity of information about the Palaeolithic succession in the Asiatic neighbours of Australia does not yet permit closer comparison.

Acoustic investigation of wall jet over a backward-facing step using a microphone phased array

The acoustic properties of a wall jet over a hard-walled backward-facing step of aspect ratios 6, 3, 2, and 1.5 are studied using a 24-channel microphone phased array at Mach numbers up to M=0.6. The Reynolds number based on inflow velocity and step height assumes values from Reh=3.0×104 to 7.2×105. Flow without and with side walls is considered. The experimental setup is open in the wall-normal direction and the expansion ratio is effectively 1. In case of flow through a duct, symmetry of the flow in the spanwise direction is lost downstream of separation at all but the largest aspect ratio as revealed by oil paint flow visualization. Hydrodynamic scattering of turbulence from the trailing edge of the step contributes significantly to the radiated sound. Reflection of acoustic waves from the bottom plate results in a modulation of power spectral densities. Acoustic source localization has been conducted using a 24-channel microphone phased array. Convective mean-flow effects on the apparent source origin have been assessed by placing a loudspeaker underneath a perforated flat plate and evaluating the displacement of the beamforming peak with inflow Mach number. Two source mechanisms are found near the step. One is due to interaction of the turbulent wall jet with the convex edge of the step. Free-stream turbulence sound is found to be peaked downstream of the step. Presence of the side walls increases free-stream sound. Results of the flow visualization are correlated with acoustic source maps. Trailing-edge sound and free-stream turbulence sound can be discriminated using source localization.

Arthroscopic Repair of Separation of Anterior Intermeniscal Ligament

Objectives:Aim of this article is to present and discuss a patient with separation of anterior intermeniscal ligament which was repaired arthroscopically.Methods:Anterior intermeniscal ligament (AIML) (transverse geniculate ligament or anterior transvers ligament) is an intraarticular structure connecting anterior convex edge of lateral meniscle to anterior tip of medial meniscle; limits anterior movement of menisci during extension and prevents pressure application of condylar surfaces onto menisci; and also limits anterior-posterior separation of anterior horn of medial meniscus during low degrees of flexion. AIML was found in 69 to 94 percent in different studies.Results:A thirty-eight year-old female patient referred our clinic with complaints of pain in right knee for a year that responds to pain killers, increasing with climbing stairs and decreasing with rest. Synovium origined mass was seen on MRI with contrast applied after an intraarticular mass seen on MRI. She undervent surgery and the mass in the medial of joint space considered as pigmented villonodular sinovitis was resected arthroscopically. During arthroscopy, separation of anterior marge of AIML and elevation of anterior horns of both medial and lateral were noticed. Using no 1 PDS suture AIML was pulled downwards from anterior marge and fixed. After fixation AIML and anterior horns of menisci replaced on tibial plateu again.Conclusion:As injuries of AIML which has an important role at stabilization of menisci during knee motions are seen very rarely, freuquency of AIML was reported 9.75 percent in a cadaver study and 75 percent of them was accompanied by medial meniscal tear. We could not find any other clinical study reporting AIML injury in the literature. As we apply arthroscopical intervention in order to resect intraarticular mass considered as pigmented villonodular synovitis, anterior separation of AIML and elevation of anterior horn of both menisci were noticed coincidentally and then were repaired. As the arthroscopical evaluation due to injuries of intraarticular structures is performed, AIML should also be evaluated, if necessary, repair should be performed in order to obtain stabilization of anterior horns of menisci.

An Efficient Improved Algorithm of Convex Hull

This paper introduced points and directed line segment relation judgment method, the characteristics of generation and Graham method using the original convex hull generation algorithm of convex hull discrete points of the convex hull, an improved algorithm for planar discrete point set is proposed. The main idea is to use quadrilateral to divide planar discrete point set into five blocks, and then by judgment in addition to the four district quadrilateral internally within the point is in a convex edge. The result shows that the method is relatively simple program, high computational efficiency.

Isogeometric segmentation: The case of contractible solids without non-convex edges

We present a novel technique for segmenting a three-dimensional solid with a 3-vertex-connected edge graph consisting of only convex edges into a collection of topological hexahedra. Our method is based on the edge graph, which is defined by the sharp edges between the boundary surfaces of the solid. We repeatedly decompose the solid into smaller solids until all of them belong to a certain class of predefined base solids. The splitting step of the algorithm is based on simple combinatorial and geometric criteria. The segmentation technique described in the paper is part of a process pipeline for solving the isogeometric segmentation problem that we outline in the paper.

An Approach to Recognize Machining Features for In-Process Models by Using a Hybrid Graph and Rule-Based Method

A hybrid graph and rule-based method for recognizing machining features is proposed in this paper, which aims to get the machining feature in 3D in-process model construction system. Initially, the attributed adjacency graph (AAG) of the input MBD models is constructed and represented in matrix form. After that, by deleting the convex edges of the AAG, the concave sub-graphs are generated. For obtaining the volumetric features, their concave sub-graphs are matched with the feature template graphs in a pre-defined library; for those which can be generated by sweeping the edge loops, such as open pocket, closed pocket, through pocket and slot, their features are recognized by using rules. In experimental section, an example is given to illustrate the validity and effectiveness of the proposed method.

Convex geometric [formula omitted]-quasiplanar representations of semi-bar [formula omitted]-visibility graphs

Semi-bar k-visibility graphs are graphs for which vertices can be drawn as horizontal segments with left endpoints on the y-axis (semi-bars) and edges can be drawn as vertical segments (sightlines) so that two semi-bars are visible to each other if and only if there is a sightline which intersects them and at most k other semi-bars. Cyclic semi-bar k-visibility graphs are graphs for which vertices can be drawn as segments with one endpoint at the origin (semi-bars) and edges can be drawn as arcs of circles centered at the origin (sightlines) so that two semi-bars are visible to each other if and only if there is a sightline which intersects them and at most k other semi-bars. We show that every semi-bar or cyclic semi-bar k-visibility graph can be represented in the plane with vertices drawn as points in convex position and edges drawn as segments so that there are no k+2 pairwise crossing edges. Furthermore, we prove that the class of graphs having cyclic semi-bar k-visibility representations with semi-bars of different lengths is the same as the class of (2k+2)-degenerate graphs that can be represented in the plane with vertices drawn as points in convex position and edges drawn as segments so that there are no k+2 pairwise crossing edges and so that adding any edge would result in k+2 pairwise crossing edges.

J0410304 凸型エッジインデント法による硬質皮膜のはく離強度評価([J041-03]工業材料の変形特性・強度およびそのモデル化 クリープ・変態・被膜強度・締結,機械材料・材料加工部門)

J0410304 凸型エッジインデント法による硬質皮膜のはく離強度評価([J041-03]工業材料の変形特性・強度およびそのモデル化 クリープ・変態・被膜強度・締結,機械材料・材料加工部門)

Wood bending mechanics: effect of resultant end-force

An innovative means of measuring the end-forces in a softened wood specimen during a bending process has been developed, incorporating a resultant end-force sensor. The impact of end-forces on wood deformation and associated bending performance has been investigated, and a correlation was found to exist between end-force and bending performance. The technique enables the systematic control of axial compression end-forces so that bending induced wood failure, as measured by longitudinal strain at the convex edge, can be minimised. While incorporating traditional manual end-force adjustment, it is envisaged that that this technique could facilitate automation of the bending process. Friction was identified as a significant impediment to the establishment of a reliable relationship between end-force and wood strain during bending.

Adhesion of Osteoblasts to a Vertically Aligned TiO2 Nanotube Surface

The adhesion of cells to vertically aligned TiO2 nanotubes is reviewed. The attraction between a negatively charged nanotube surface and a negatively charged osteoblast is facilitated by charged protein-mediators like proteins with a quadrupolar internal charge distribution, fibronectin and vitronectin. It is shown that adhesion and spreading of osteoblasts on vertically aligned TiO2 nanotube surfaces depend on the diameter of the nanotubes. Apparently, a small diameter nanotube surface has on average more sharp convex edges per unit area than a large one, leading to stronger binding affinity on its surface.

Eating Activity Detection from Images Acquired by a Wearable Camera.

We present an eating activity detection method via automatic detecting dining plates from images acquired chronically by a wearable camera. Convex edge segments and their combinations within each input image are modeled with respect to probabilities of belonging to candidate ellipses. Then, a dining plate is determined according to a confidence score. Finally, the presence/absence of an eating event in an image sequence is determined by analyzing successive frames. Our experimental results verified the effectiveness of this method.

Dual modes of motility at the leading edge of migrating epithelial cell sheets

Purse-string healing is driven by contraction of actin/myosin cables that span cells at wound edges, and it is the predominant mode of closing small round wounds in embryonic and some adult epithelia. Wounds can also heal by cell crawling, and my colleagues and I have shown previously that the presence of unconstrained, straight edges in sheets of epithelial cells is a sufficient signal to induce healing by crawling. Here, it is reported that the presence of highly concave edges, which are free or physically constrained by an inert material (agarose), is sufficient to induce formation of purse strings. It was determined that neither of the two types of healing required cell damage or other potential stimuli by using the particularly gentle procedure of introducing gaps by digesting agarose blocks imbedded in the cell sheets. Movement by crawling depends on signaling by the EGF receptor (EGFR); however, this was not required for purse-string contraction. A migrating epithelial cell sheet usually produces finger-like projections of crawling cells. The cells between fingers contain continuous actin cables, which were also determined to contain myosin IIA and exhibit additional characteristics of purse strings. When crawling was blocked by inhibition of EGFR signaling, the concave regions continued to move, suggesting that both mechanisms contribute to propel the sheets forward. Wounding epithelial cell sheets causes activation of the EGFR, which triggers movement by crawling. The EGFR was found to be activated only at straight and convex edges, which explains how both types of movement can coexist at leading epithelial edges.

Diffusion and aggregation of adatoms on faceted Pd/Mo(111) surface

Diffusion of Pd adatoms on faceted Pd/Mo(111) surface with hill and valley structure is studied by kinetic Monte Carlo method. The surface consists of {211} channeled facets separated by concave and convex edges. It is shown that diffusion on the faceted surface is significantly reduced with comparison to diffusion on (112) surface by the presence of concave edges. A simple formula for the diffusion coefficient is proposed. The growth of linear structures, studied at low coverage θ=0.1, depends on the cross-channel diffusion, although the cross-channel diffusion coefficient is by 6–8 orders of magnitude smaller than the in-channel diffusion coefficient. We observed that most of atomic structures grow in valleys and the average size of the structure increases with increase of facet size.

A novel segmentation approach for improving diagnostic accuracy of CAD systems for detecting lung cancer from chest computed tomography images

Segmentation of lung tissue is an important and challenging task in any computer aided diagnosis system. The accuracy of the segmentation subsystem determines the performance of the other subsystems in any computer aided diagnosis system based on image analysis. We propose a novel technique for segmentation of lung tissue from computed tomography of the chest. Manual segmentation of lung parenchyma becomes difficult with an enormous volume of images. The goal of this work is to present an automated approach to segmentation of lung parenchyma from the rest of the chest CT image. The approach involves the conventional optimal thresholding technique and operations based on convex edge and centroid properties of the lung region. The segmentation technique proposed in this article can be used to preprocess lung images given to a computer aided diagnosis system for diagnosis of lung disorders. This improves the diagnostic performance of the system. This has been tested by using it in a computer aided diagnosis system that was used for detection of lung cancer from chest computed tomography images. The results obtained show that the lungs can be correctly segmented even in the presence of peripheral pathology bearing regions; pathology bearing regions that could not be detected using a CAD system that applies optimal thresholding could be detected using a CAD system using out proposed approach for segmentation of lungs.

A Gamut Boundary Description Method Based on Graham Algorithm for Laser TV

To take full advantage of high brightness, wide color gamut and high saturation of the Laser TV, kinds of gamut expansion methods emerged. Most of the methods are based on the hue unchangeable principle. So before gamut expansion, the boundary of Laser TV gamut and that of current display standard gamut should be first obtained. But the traditional method for getting the device color gamut based on physical model was not accurate enough for the Laser TV gamut expansion. Based on this situation, An improved gamut boundary description method based on graham algorithm for laser TV was proposed in this paper. The method first used Convex Hull Algorithm to detect the edge points on the convex edge, and then through multiple iterations to calculate the Concave edge points between the convex edge points. Result of experiment on the CIE L*a*b* color space showed this kind of method could give a more accurate description of the Laser TV gamut boundary.