Fusion of 3D LIDAR and Camera Data for Object Detection in Autonomous Vehicle Applications

It’s critical for an autonomous vehicle to acquire accurate and real-time information of the objects in its vicinity, which will fully guarantee the safety of the passengers and vehicle in various environment. 3D LIDAR can directly obtain the position and geometrical structure of the object within its detection range, while vision camera is very suitable for object recognition. Accordingly, this paper presents a novel object detection and identification method fusing the complementary information of two kind of sensors. We first utilize the 3D LIDAR data to generate accurate object-region proposals effectively. Then, these candidates are mapped into the image space where the regions of interest (ROI) of the proposals are selected and input to a convolutional neural network (CNN) for further object recognition. In order to identify all sizes of objects precisely, we combine the features of the last three layers of the CNN to extract multi-scale features of the ROIs. The evaluation results on the KITTI dataset demonstrate that : (1) Unlike sliding windows that produce thousands of candidate object-region proposals, 3D LIDAR provides an average of 86 real candidates per frame and the minimal recall rate is higher than 95%, which greatly lowers the proposals extraction time; (2) The average processing time for each frame of the proposed method is only 66.79ms, which meets the real-time demand of autonomous vehicles; (3) The average identification accuracies of our method for car and pedestrian on the moderate level are 89.04% and 78.18% respectively, which outperform most previous methods

An inventory of invasive alien species in China

Invasive alien species (IAS) are a major global challenge requiring urgent action, and the Strategic Plan for Biodiversity (2011–2020) of the Convention on Biological Diversity (CBD) includes a target on the issue. Meeting the target requires an understanding of invasion patterns. However, national or regional analyses of invasions are limited to developed countries. We identified 488 IAS in China’s terrestrial habitats, inland waters and marine ecosystems based on available literature and field work, including 171 animals, 265 plants, 26 fungi, 3 protists, 11 procaryots, and 12 viruses. Terrestrial plants account for 51.6% of the total number of IAS, and terrestrial invertebrates (104 species) for 21.3%. Of the total numbers, 67.9% of plant IAS and 34.8% of animal IAS were introduced intentionally. All other taxa were introduced unintentionally despite very few animal and plant species that invaded naturally. In terms of habitats, 64.3% of IAS occur on farmlands, 13.9% in forests, 8.4% in marine ecosystems, 7.3% in inland waters, and 6.1% in residential areas. Half of all IAS (51.1%) originate from North and South America, 18.3% from Europe, 17.3% from Asia not including China, 7.2% from Africa, 1.8% from Oceania, and the origin of the remaining 4.3% IAS is unknown. The distribution of IAS can be divided into three zones. Most IAS are distributed in coastal provinces and the Yunnan province; provinces in Middle China have fewer IAS, and most provinces in West China have the least number of IAS. Sites where IAS were first detected are mainly distributed in the coastal region, the Yunnan Province and the Xinjiang Uyghur Autonomous Region. The number of newly emerged IAS has been increasing since 1850. The cumulative number of firstly detected IAS grew exponentially

Eightfold Fermionic Excitation in a Charge Density Wave Compound

Unconventional quasiparticle excitations in condensed matter systems have become one of the most important research frontiers. Beyond two- and fourfold degenerate Weyl and Dirac fermions, three-, six- and eightfold symmetry protected degeneracies have been predicted however remain challenging to realize in solid state materials. Here, charge density wave compound TaTe4 is proposed to hold eightfold fermionic excitation and Dirac point in energy bands. High quality TaTe4 single crystals are prepared, where the charge density wave is revealed by directly imaging the atomic structure and a pseudogap of about 45 meV on the surface. Shubnikov de-Haas oscillations of TaTe4 are consistent with band structure calculation. Scanning tunneling microscopy reveals atomic step edge states on the surface of TaTe4. This work uncovers that charge density wave is able to induce new topological phases and sheds new light on the novel excitations in condensed matter materials.Comment: Accepted by PRB: https://journals.aps.org/prb/accepted/7907cK4eW0b1ee0b93fd67c1b42942bbb08eafc3

Do Credit Associations Compete with Each Other in Japanese Regional Lending Markets?

This paper examines whether credit associations in Japanese regional lending markets compete on price now that Japanese financial authorities have replaced the convoy system of financial regulation with the principle of competition. Specifically, the effects of the market share of credit associations in regional markets on their lending rates are empirically investigated. Accordingly, we determined that credit associations compete with each other in regional lending markets by using two different proxies for the market share held by credit associations in a region. The first proxy was the credit associations’ share of all deposits in a region and the second was the credit associations’ share of all branch offices in a region. In addition, credit associations that face more intense competition from regional banks in regional markets were found to face more intense competition from other credit associations

DATA for Peng et al.

The Excel file includes 10 datasets associated with the manuscript

Domesticated honeybees facilitate interspecific hybridization between two Taraxacum congeners

Interspecific hybridization is common in plants under natural conditions, but the ecological mechanisms underlying when and how it happens have not fully been understood.Taraxacum calanthodium and Taraxacum lugubre are two herbaceous annals co-occurring in alpine meadows of the eastern Tibetan Plateau that share the same pollinators including domestic honeybees during their overlapping flowering times. Because honeybees tend to visit flowers less discriminatively when bee densities are high, we hypothesized that intense apiculture would facilitate hybridization between these two congeneric species. We tested this hypothesis by examining the frequencies of the two parent species occurrence and the hybrid (based on morphological and genetic differences) along three transects radiating from well-established apiaries. Experiments show that both T.calanthodium and T.lugubre produce seeds sexually and asexually, and that they can hybridize via pollen transfer. Bee visitation rates and the frequency of the hybrid were significantly higher in the sites nearest to apiaries compared to distant site along each of the three transects. The hybrids were consistently genetically intermediate between the two species, as indicated by simple sequence repeat-based analyses.Synthesis. These data indicate that domestic honeybees foster interspecific hybridization between the two Taraxacum species and that anthropogenic effects on pollen vectors can significantly influence species hybridization in nature. We suggest that more effort should be made to quantify the effects of environmental change on pollinators and their effects on species evolution

Data from: Domesticated honeybees facilitate interspecific hybridization between two Taraxacum congeners

1. Interspecific hybridization is common in plants under natural conditions, but the ecological mechanisms underlying when and how it happens have not fully been understood. 2. Taraxacum calanthodium and T. lugubre are two herbaceous annals co-occurring in alpine meadows of the eastern Tibetan Plateau that share the same pollinators including domestic honeybees during their overlapping flowering times. Because honeybees tend to visit flowers less discriminatively when bee densities are high, we hypothesized that intense apiculture would facilitate hybridization between these two congeneric species. 3. We tested this hypothesis by examining the frequencies of the two parent species occurrence and the hybrid (based on morphological and genetic differences) along three transects radiating from well-established apiaries. 4. Experiments show that both Taraxacum calanthodium and T. lugubre produce seeds sexually and asexually, and that they can hybridize via pollen transfer. Bee visitation rates and the frequency of the hybrid were significantly higher in the sites nearest to apiaries compared to distant site along each of the three transects. The hybrids were consistently genetically intermediate between the two species, as indicated by Simple Sequence Repeat- based analyses. 5. Synthesis. These data indicate that domestic honeybees foster interspecific hybridization between the two Taraxacum species and that anthropogenic effects on pollen vectors can significantly influence species hybridization in nature. We suggest that more effort should be made to quantify the effects of environmental change on pollinators and their effects on species evolution

Image Antiblurring and Statistic Filter of Feature Space Displacement: Application to Visual Odometry for Outdoor Ground Vehicle

Precise, reliable, and low-cost vehicular localization across a continuous spatiotemporal domain is an important problem in the field of outdoor ground vehicles. This paper proposes a visual odometry algorithm, where an ultrarobust and fast feature-matching scheme is combined with an effective antiblurring frame selection strategy. Our method follows the procedure of finding feature correspondences from consecutive frames and minimizing their reprojection error. The blurred image is a great challenge for localization with a sharp turn or fast movement. So we attempt to mitigate the impact of blur with an image singular value decomposition antiblurring algorithm. Moreover, a statistic filter of feature space displacement and circle matching are proposed to screen or prune potential matching features, so as to remove the outliers caused by mismatching. An evaluation of benchmark dataset KITTI and real outdoor data, with blur, low texture, and illumination change, demonstrates that the proposed ego-motion scheme significantly achieved performance with respect to the other state-of-the-art visual odometry approaches to a certain extent