Design of a Tripod-Shaped Radiator Patch Antenna for Ultra-Wideband Direction Finding.

As UWB technology develops and devices become smaller, miniaturization techniques for an array antenna system are required. In addition, more in-depth research is needed for UWB direction-finding techniques using channel impulse response (CIR) data. This paper proposes an ultra-wideband (UWB) antenna using a single-radiator multiple-port (SRMP) design for the direction-finding systems of smart devices. The proposed SRMP antenna was designed using a single tripod-shaped patch that can replace the array system. The tripod-shaped radiator was optimized using the edge shape design function to improve its broadband and mutual coupling characteristics. For performance verification, the proposed antenna was fabricated, and the reflection coefficient, mutual coupling, and radiation patterns were measured in a fully anechoic chamber. The proposed antenna has an operating frequency band of 6.1 GHz (from 5.8 GHz to 11.9 GHz) for port 1 and a measured mutual coupling of -14.8 dB at 8 GHz. The SRMP antenna has measured maximum gains of 3.5 dBi for port 1 and 2.9 dBi for port 2. To examine the direction-finding performance, the fabricated antenna was connected to a circuit module with a DW3000 chip, which is widely employed in commercial mobile UWB systems. The direction of arrival (DoA) results using the measured CIR data show root-mean-square (RMS) errors of 1.57° and 4.58° at distances of 30 cm and 60 cm.

Deep Learning for Counting People from UWB Channel Impulse Response Signals.

The use of higher frequency bands compared to other wireless communication protocols enhances the capability of accurately determining locations from ultra-wideband (UWB) signals. It can also be used to estimate the number of people in a room based on the waveform of the channel impulse response (CIR) from UWB transceivers. In this paper, we apply deep neural networks to UWB CIR signals for the purpose of estimating the number of people in a room. We especially focus on empirically investigating the various network architectures for classification from single UWB CIR data, as well as from various ensemble configurations. We present our processes for acquiring and preprocessing CIR data, our designs of the different network architectures and ensembles that were applied, and the comparative experimental evaluations. We demonstrate that deep neural networks can accurately classify the number of people within a Line of Sight (LoS), thereby achieving an 99% performance and efficiency with respect to both memory size and FLOPs (Floating Point Operations Per Second).

Implantation of canine umbilical cord blood-derived mesenchymal stem cells mixed with beta-tricalcium phosphate enhances osteogenesis in bone defect model dogs.

This study was performed to evaluate the osteogenic effect of allogenic canine umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) mixed with beta-tricalcium phosphate (beta-TCP) in orthotopic implantation. Seven hundred milligrams of beta-TCP mixed with 1 x 10(6) UCB-MSCs diluted with 0.5 ml of saline (group CM) and mixed with the same volume of saline as control (group C) were implanted into a 1.5 cm diaphyseal defect and wrapped with PLGC membrane in the radius of Beagle dogs. Radiographs of the antebrachium were made after surgery. The implants were harvested 12 weeks after implantation and specimens were stained with H&E, toluidine blue and Villanueva-Goldner stains for histological examination and histomorphometric analysis of new bone formation. Additionally, UCB-MSCs were applied to a dog with non-union fracture. Radiographically, continuity between implant and host bone was evident at only one of six interfaces in group C by 12 weeks, but in three of six interfaces in group CM. Radiolucency was found only near the bone end in group C at 12 weeks after implantation, but in the entire graft in group CM. Histologically, bone formation was observed around beta-TCP in longitudinal sections of implant in both groups. Histomorphometric analysis revealed significantly increased new bone formation in group CM at 12 weeks after implantation (p < 0.05). When applied to the non-union fracture, fracture healing was identified by 6 weeks after injection of UCB-MSCs. The present study indicates that a mixture of UCB-MSCs and beta-TCP is a promising osteogenic material for repairing bone defects.

Protective effects of ginseng saponins on 3-nitropropionic acid-induced striatal degeneration in rats.

The precise cause of neuronal cell death in Huntington's disease (HD) is not known. Systemic administration of 3-nitropropionic acid (3-NP), an irreversible succinate dehydrogenase inhibitor, not only induces a cellular ATP depletions but also causes a selective striatal degeneration similar to that seen in HD. Recent accumulating reports have shown that ginseng saponins (GTS), the major active ingredients of Panax ginseng, have protective effects against neurotoxin insults. In the present study, we examined in vitro and in vivo effects of GTS on striatal neurotoxicity induced by repeated treatment of 3-NP in rats. Here, we report that systemic administration of GTS produced significant protections against systemic 3-NP- and intrastriatal malonate-induced lesions in rat striatum with dose-dependent manner. GTS also improved significantly 3-NP-caused behavioral impairment and extended survival. However, GTS itself had no effect on 3-NP-induced inhibition of succinate dehydrogenase activity. To explain the mechanisms underlying in vivo protective effects of GTS against 3-NP-induced striatal degeneration, we examined in vitro effect of GTS against 3-NP-caused cytotoxicity using cultured rat striatal neurons. We found that GTS inhibited 3-NP-induced intracellular Ca(2+) elevations. GTS restored 3-NP-caused mitochondrial transmembrane potential reduction in cultured rat striatal neurons. GTS also prevented 3-NP-induced striatal neuronal cell deaths with dose-dependent manner. The EC(50) was 12.6 +/- 0. 7microg/ml. These results suggest that in vivo protective effects of GTS against 3-NP-induced rat striatal degeneration might be achieved via in vitro inhibition of 3-NP-induced intracellular Ca(2+) elevations and cytotoxicity of striatal neurons.