On the Csorgo-Révész increments of finite dimensional Gaussian random fields

In this paper, we establish some limit theorems on the combined Csorgo-Révész increments with moduli of continuity for finite dimensional Gaussian random fields under mild conditions, via estimating upper bounds of large deviation probabilities on suprema of the finite dimensional Gaussian random fields.Csorgo-Révész increment; Gaussian process; random field; modulus of continuity; quasi-increasing; regularly varying function; large deviation probability.

Organic core-sheath nanowire artificial synapses with femtojoule energy consumption

Emulation of biological synapses is an important step toward construction of large-scale brain-inspired electronics. Despite remarkable progress in emulating synaptic functions, current synaptic devices still consume energy that is orders of magnitude greater than do biological synapses (similar to 10 fJ per synaptic event). Reduction of energy consumption of artificial synapses remains a difficult challenge. We report organic nanowire (ONW) synaptic transistors (STs) that emulate the important working principles of a biological synapse. The ONWs emulate the morphology of nerve fibers. With a core-sheath-structured ONW active channel and a well-confined 300-nm channel length obtained using ONW lithography, similar to 1.23 fJ per synaptic event for individual ONW was attained, which rivals that of biological synapses. The ONW STs provide a significant step toward realizing low-energy-consuming artificial intelligent electronics and open new approaches to assembling soft neuromorphic systems with nanometer feature size.1161Yscopu

Improved Real-Time Monocular SLAM Using Semantic Segmentation on Selective Frames

Monocular simultaneous localization and mapping (SLAM) is emerging in advanced driver assistance systems and autonomous driving, because a single camera is cheap and easy to install. Conventional monocular SLAM has two major challenges leading inaccurate localization and mapping. First, it is challenging to estimate scales in localization and mapping. Second, conventional monocular SLAM uses inappropriate mapping factors such as dynamic objects and low-parallax areas in mapping. This paper proposes an improved real-time monocular SLAM that resolves the aforementioned challenges by efficiently using deep learning-based semantic segmentation. To achieve the real-time execution of the proposed method, we apply semantic segmentation only to downsampled keyframes in parallel with mapping processes. In addition, the proposed method corrects scales of camera poses and three-dimensional (3D) points, using estimated ground plane from road-labeled 3D points and the real camera height. The proposed method also removes inappropriate corner features labeled as moving objects and low parallax areas. Experiments with eight video sequences demonstrate that the proposed monocular SLAM system achieves significantly improved and comparable trajectory tracking accuracy, compared to existing state-of-the-art monocular and stereo SLAM systems, respectively. The proposed system can achieve real-time tracking on a standard CPU potentially with a standard GPU support, whereas existing segmentation-aided monocular SLAM does not

Multiuser diversity and multiplexing using multiple random beams in wireless systems

In this paper, we propose a new multiple-antenna transmission scheme that can simultaneously achieve both diversity and multiplexing gain in the multi-user domain, by using multiple random beams. Multiple beams are generated so that the users encounter multiple channels at the same time, enabling the use of multi-user diversity through each channel. Although the signal-to-noise power ratio (SNR) of each channel is reduced in proportion to the number of beams, multiple beams are generated so that the multiplexing gain is larger than the decrease of SNR, increasing the overall system capacity

A novel downlink beamforming scheme for FDD/SDMA systems

When beamforming is employed in the uplink without feedback channel, the beam pattern for the downlink can be generated using the weight used for uplink beamforming. However, this scheme may result in significantly performance degradation in the frequency division duplex (FDD) because of carrier frequency offset between the uplink and downlink. In this paper we propose a novel downlink beamforming algorithm based on least square method with some constraint points which have same gain in the up/downlink beam pattern. From the constraint points, we generate downlink weight and also propose how to choose the constraint points in order to satisfy the desired signal-to-interference power ratio. Simulation results show that the proposed method can sufficiently reduce the interference from other space division multiple access (SDMA) signals, providing interference-free spatial channel

Improving Neural Radiance Field using Near-Surface Sampling with Point Cloud Generation

Neural radiance field (NeRF) is an emerging view synthesis method that samples points in a three-dimensional (3D) space and estimates their existence and color probabilities. The disadvantage of NeRF is that it requires a long training time since it samples many 3D points. In addition, if one samples points from occluded regions or in the space where an object is unlikely to exist, the rendering quality of NeRF can be degraded. These issues can be solved by estimating the geometry of 3D scene. This paper proposes a near-surface sampling framework to improve the rendering quality of NeRF. To this end, the proposed method estimates the surface of a 3D object using depth images of the training set and sampling is performed around there only. To obtain depth information on a novel view, the paper proposes a 3D point cloud generation method and a simple refining method for projected depth from a point cloud. Experimental results show that the proposed near-surface sampling NeRF framework can significantly improve the rendering quality, compared to the original NeRF and a state-of-the-art depth-based NeRF method. In addition, one can significantly accelerate the training time of a NeRF model with the proposed near-surface sampling framework.Comment: 13 figures, 2 table

Subacute Neurological Deterioration with Selective Axonal Injury in Patients with Acute Ischemic Stroke following Reperfusion of Middle Cerebral Artery Occlusion

To date, the long-term effects of reperfusion on the salvaged brain tissues have not been addressed in the literature. We report 4 cases presenting subacute neurological deteriorations with selective axonal injury following reperfusion therapies for acute ischemic stroke. Our case series based on 4 patients showed common features distinct from those of early reperfusion injury in that (1) the neurological symptoms developed after 1-2 months of reperfusion therapies, (2) these symptoms were accompanied by the subcortical white matter changes on brain MRI, and (3) these findings were mostly reversible with time. This suggests that axons in the reperfused brain may be vulnerable to further neurological injury

Selective Targeting of Bromodomains of the Bromodomain-PHD Fingers Family Impairs Osteoclast Differentiation

Histone acetyltransferases of the MYST family are recruited to chromatin by BRPF scaffolding proteins. We explored functional consequences and the therapeutic potential of inhibitors targeting acetyl-lysine dependent protein interaction domains (bromodomains) present in BRPF1-3 in bone maintenance. We report three potent and selective inhibitors: one (PFI-4) with high selectivity for the BRPF1B isoform and two pan-BRPF bromodomain inhibitors (OF-1, NI-57). The developed inhibitors displaced BRPF bromodomains from chromatin and did not inhibit cell growth and proliferation. Intriguingly, the inhibitors impaired RANKL-induced differentiation of primary murine bone marrow cells and human primary monocytes into bone resorbing osteoclasts by specifically repressing transcriptional programs required for osteoclastogenesis. The data suggest a key role of BRPF in regulating gene expression during osteoclastogenesis, and the excellent druggability of these bromodomains may lead to new treatment strategies for patients suffering from bone loss or osteolytic malignant bone lesions