Distinctive Local Features Research Articles

Embedding class information into local invariant features by low-dimensional retinotopic mapping

In this paper, we propose a new general framework to obtain more distinctive local invariant features by projecting the original feature descriptors into low-dimensional feature space, while simultaneously incorporating also class information. In the resulting feature space, the features from different objects project to separate areas, while locally the metric relations between features corresponding to the same object are preserved. The low-dimensional feature embedding is obtained by a modified version of classical Multidimensional Scaling, which we call supervised Multidimensional Scaling (sMDS). Experimental results on a database containing images of several different objects with large variation in scale, viewpoint, illumination conditions and background clutter support the view that embedding class information into the feature representation is beneficial and results in more accurate object recognition.

Modeling vehicle emissions in different types of Chinese cities: Importance of vehicle fleet and local features

We propose a method to simulate vehicle emissions in Chinese cities of different sizes and development stages. Twenty two cities are examined in this study. The target year is 2007. Among the cities, the vehicle emission factors were remarkably different (the highest is 50–90% higher than the lowest) owing to their distinct local features and vehicle technology levels, and the major contributors to total vehicle emissions were also different. A substantial increase in vehicle emissions is foreseeable unless stronger measures are implemented because the benefit of current policies can be quickly offset by the vehicle growth. Major efforts should be focused on all cities, especially developing cities where the requirements are lenient. This work aims a better understanding of vehicle emissions in all types of Chinese cities. The proposed method could benefit national emission inventory studies in improving accuracy and help in designing national and local policies for vehicle emission control.

Rotation and radial electric field in the plasma edge with resonant magnetic perturbation at TEXTOR

In this paper the results of a systematic experimental assessment of the plasma edge rotation and radial electric field with application of resonant magnetic perturbation (RMP) are presented. The results are based on the radially resolved measurement of the poloidal (vpol) and toroidal (vtor) rotation. It is shown that the radial electric field Er can be deduced from the radial force balance when small amplitude resonant magnetic perturbations are applied to the plasma boundary (Br/Btor ∼ 10−4).Both vpol and vtor spin-up in the ion-diamagnetic-drift and co-current direction, respectively, with increasing external perturbation field (Δvpol ∼ 15 km s−1, Δvtor ∼ 2–5 km s−1) yielding an increase in Er by ΔEr,max = 9 kV m−1. The toroidal rotation increases over the whole radius while the poloidal rotation shows distinct local features driving the evolution of the Er-profiles. Depending on the edge safety factor a local (at the q = 5/2 rational surface) increase in the shear rate ΩE×B (ΔΩq=5/2 = 1.4 × 105 s−1) or reduced shearing can occur. Increased shearing is correlated with an improved particle confinement with an increase in the particle confinement time by Δτp = +40%. Increasing the local resonant amplitude by 30% induces a reduced density level, the so-called RMP induced pump-out. At this confinement stage the shear rate decreases by 15% correlated with a significant drop in particle confinement (Δτp = −30%).Field line tracing in the vacuum approximation gives indications towards explaining the threshold behaviour connecting the shearing rate, confinement stages and magnetic topology to the amount of applied RMP. However, this basic approach does not account for plasma response and the results presented are linked in the discussion section to recent results on the link between rotation and plasma response as well as on the transport features of RMP.

A Partial Intensity Invariant Feature Descriptor for Multimodal Retinal Image Registration

Detection of vascular bifurcations is a challenging task in multimodal retinal image registration. Existing algorithms based on bifurcations usually fail in correctly aligning poor quality retinal image pairs. To solve this problem, we propose a novel highly distinctive local feature descriptor named partial intensity invariant feature descriptor (PIIFD) and describe a robust automatic retinal image registration framework named Harris-PIIFD. PIIFD is invariant to image rotation, partially invariant to image intensity, affine transformation, and viewpoint/perspective change. Our Harris-PIIFD framework consists of four steps. First, corner points are used as control point candidates instead of bifurcations since corner points are sufficient and uniformly distributed across the image domain. Second, PIIFDs are extracted for all corner points, and a bilateral matching technique is applied to identify corresponding PIIFDs matches between image pairs. Third, incorrect matches are removed and inaccurate matches are refined. Finally, an adaptive transformation is used to register the image pairs. PIIFD is so distinctive that it can be correctly identified even in nonvascular areas. When tested on 168 pairs of multimodal retinal images, the Harris-PIIFD far outperforms existing algorithms in terms of robustness, accuracy, and computational efficiency.

Introduction: Critical Perspectives on Child and Youth Participation in Australia and New Zealand/Aotearoa

Children, Youth and Environments 16(2), 2006 Introduction: Critical Perspectives on Child and Youth Participation in Australia and New Zealand/Aotearoa1 Anita Harris School of Political and Social Inquiry Monash University Citation: Harris, Anita (2006). “Introduction: Critical Perspectives on Child and Youth Participation in Australia and New Zealand/Aotearoa.” Children, Youth and Environments 16(2): 220-230. Issues of child and youth participation in Australia and New Zealand/Aotearoa have distinctive local features; at the same time, they share many qualities with those in other Western countries. In this introduction, I provide some regional context for the participation debate by discussing the demographic, socioeconomic and political environment for children and young people in Australia and New Zealand/Aotearoa. I identify a tension between social changes that have ushered in an agenda of child and youth participatory rights and the economic and political forces that have made meaningful participation for a diverse range of youth difficult to achieve. The collection of articles for this special focus region highlights in various ways how this tension has become the key challenge for participatory programs, research and policy in the region. Throughout the introduction, I refer exclusively to the work of authors from Australia and New Zealand to provide readers with an overview of local work on this topic. A demographic snapshot of children and youth in Australia and New Zealand/Aotearoa helps to situate debates about participation in the region. Children and young people constitute just over 27 percent of the populations in both Australia and New Zealand/Aotearoa (Australian Bureau of Statistics 2001; Statistics New Zealand 2001). Unlike in many other Western nations, the geographical makeup of these countries is such that youth often live in rural and regional areas that are isolated from major urban centers and cities. There is also significant ethnic, cultural and religious diversity amongst children and youth in Australia and New Zealand/Aotearoa, as both countries are home to Indigenous populations (Aboriginal and Torres Strait Islander peoples in Australia and Maori in 1 Aotearoa is the Maori (Indigenous) name for New Zealand. Introduction: Critical Perspectives on Child and Youth Participation in Australia … 221 New Zealand/Aotearoa); both were colonized by Britain in the 18th and 19th centuries; and both countries have received migrants and refugees from the AsiaPacific region, Europe and, more recently, Africa. Further, while the overall standard of living in these countries is high, the economic and social well-being of children and youth is mediated by class, culture and ethnicity, gender and sexuality, ability and location. The interdisciplinary nature of child and youth participation studies in the region is shaped by these demographic features of children and youth, and also reflects and responds to changing socioeconomic trends that have an impact on young people in the region. As Johanna Wyn and I (2005, 272) have written elsewhere, Australia is a large, sparsely populated continent and a population of approximately 19 million people, who live in cities and regional towns, largely concentrated on the coastal fringe. New Zealand consists of two main islands, and has a relatively small population of approximately 4 million people. While they are both migrant societies that have Indigenous populations, the different historical origins and subsequent social and economic development between the two countries means that today there are both historic and contemporary differences that impact on young people’s lives. Yet young people in Australia and New Zealand do share some common circumstances. They have grown up in English-speaking countries in the Pacific that were colonised during the 1800s. Young people born in the early 1970s in Australia and New Zealand are shaping their lives in the context of significant changes to many aspects of life that the preceding generation took for granted. These significant changes have been both positive and negative. Some historical and legal circumstances brought about by social changes of the 1960s and 1970s have greatly improved the status and position of children and young people in Australia and New Zealand/Aotearoa and have enhanced their participatory capabilities. For example, the current generation of young Australians is the first to have grown up under a constitution that recognizes Aboriginals and Torres Strait Islanders. Many young Australians...

Solution structure of BmP08, a novel short-chain scorpion toxin from Buthus martensi Karsch

A novel short-chain scorpion toxin BmP08 was purified from the venom of the Chinese scorpion Buthus martensi Karsch by a combination of gel-filtration, ion exchange, and reversed-phase chromatography. The primary sequence of BmP08 was determined using the tandem MS/MS technique and Edman degradation, as well as results of NMR sequential assignments. It is composed of 31 amino acid residues including six cysteine residues and shares less than 25% sequence identity with the known α-KTx toxins. BmP08 shows no inhibitory activity on all tested voltage-dependent and Ca 2+-activated potassium channels. The 3D-structure of BmP08 has been determined by 2D-NMR spectroscopy and molecular modeling techniques. This toxin adopts a common α/β-motif, but shows a distinctive local conformation and features a 3 10-helix and a shorter β-sheet. The unique structure is closely related to the distinct primary sequence of the toxin, especially to the novel arrangement of S–S linkages in the molecule, in which two disulfide bridges (C i –C j and C i+3 –C j+3 ) link covalently the 3 10-helix with one strand of the β-sheet structure. The electrostatic potential surface analysis of the toxin reveals salt bridges and hydrogen bonds between the basic residues and negatively charged residues nearby in BmP08, which may be unfavorable for its binding with the known voltage-dependent and Ca 2+-activated potassium channels. Thus, finding the target for this toxin should be an interesting task in the future.

Solution structure of a consensus stem-loop D RNA domain that plays important roles in regulating translation and replication in enteroviruses and rhinoviruses.

Stem-loop D from the cloverleaf RNA is a highly conserved domain within the 5'-UTR of enteroviruses and rhinoviruses. Interaction between the stem-loop D RNA and the viral 3C or 3CD proteins constitutes an essential feature of a ribonucleoprotein complex that plays a critical role in regulating viral translation and replication. Here we report the solution NMR structure of a 38-nucleotide RNA with a sequence that encompasses the entire stem-loop D domain and corresponds to the consensus sequence found in enteroviruses and rhinoviruses. Sequence variants corresponding to Poliovirus type 1 and Coxsackievirus B3 have virtually the same structure, based on small differences in chemical shifts. A substantial number (136) of (1)H-(13)C one-bond residual dipolar coupling (RDC) values were used in the structure determination in addition to conventional distance and torsion angle restraints. Inclusion of the RDC restraints was essential for achieving well-defined structures, both globally and locally. The structure of the consensus stem-loop D is an elongated A-type helical stem capped by a UACG tetraloop with a wobble UG closing base pair. Three consecutive pyrimidine base pairs (two UU and one CU pair) are present in the middle of the helical stem, creating distinctive local structural features such as a dramatically widened major groove. A dinucleotide bulge is located near the base of the stem. The bulge itself is flexible and not as well defined as the other parts of the molecule, but the flanking base pairs are intact. The peculiar spatial arrangement of the distinctive structural elements implies that they may work synergistically to achieve optimal binding affinity and specificity toward the viral 3C or 3CD proteins.

Tombs of the Yelang Period at Kele in Hezhang, Guizhou

In September-October 2000, the Guizhou Provincial Institute of Antiquity and Archaeology and Hezhang County Commission for Preservation of Ancient Monuments jointly excavated tombs of the Warring States period to Western Han times at Kele 可乐, Village in Kele Town, Hezhang 赫章 County, Guizhou 贵州 and reaped great fruits. Due to the tombs are of the ancient Yelang period and the burial custom and funerary objects have distinctive local ethnic features, the excavation aroused more interest in the academic circle.

The effects of cortical lesions on recognition of object context in a visuomotor task in the Mongolian gerbil

Two experiments were carried out in order to determine the effects of either parietal or temporal lesions on performance in a depth vision task in which gerbils normally use retinal image size (RIS) as a cue to distance. In the first experiment, gerbils were trained to jump to two training targets that differed in size and which were always presented with distinctive local features and in a particular spatial location. After lesions, gerbils were presented with further training trials and sets of probe trials in which they were presented with targets that differed in width from the training targets, and sets of local features and distal cues that either matched or mismatched those presented during training. Shams and temporal animals made predictable over- or underjumps when local feature and distal information matched, and stopped using retinal image size when they did not match. Parietal animals did not use retinal image size either during the match or the mismatch conditions. In a second experiment, gerbils with parietal lesions were shown capable of using retinal image size in a simpler task that did not contain distinguishing local features or distal cues. Taken together, these results suggest that parietal lesions in gerbils disrupt object recognition, when the purpose of the recognition process is to complete a distance estimate for a visuomotor act.

Thermal constraints on the formation of mississippi valley-type lead-zinc deposits and their implications for episodic basin dewatering and deposit genesis

Two simple constraints: that the deposits formed within 1 km of the surface, and that the temperature of the ore fluids at the time of mineral deposition was 100 degrees to 150 degrees C. For base metal deposits to form as the result of the compactive expulsion of basin brines, brine expulsion must be episodic. Episodic pulses of geopressured brines moving through the near-surface sites of ore deposition, followed by much longer periods of exposure to cool surface waters, could produce the color banding of sphalerite, the cycles of sulfide precipitation and dissolution, and the distinctive local tectonic features associated with mississippi valley-type deposits. Basin features favoring the right kind of episodic dewatering are identified.--Modified journal abstract.

Pachiz (An Ethnographic Relic of Ancient Ties Between India and Khorezm)

Anthropological field research in Khorezm and some areas of central Uzbekistan — carried out by the present author in the last few years — has made it possible to investigate not only the major topics selected in the field of the history of intellectual culture, but also a number of aspects of the earlier social life of the population of these areas. For one thing, we were able to collect data on an institution of great interest to historical anthropology that hitherto had little treatment in the literature. We refer to the traditional male societies, with their distinctive internal lives, curious method of administration, age-old unwritten constitutions, and strict supervision over adherence to the rules of behavior. These societies have many distinctive local features, but are uniform in their genetic relationship to the male alliances of primitive society.