Search results for "Telecommunications"

Underlay Device-to-Device Communications on Multiple Channels

2018

Author´s accepted manuscript (postprint). © 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Since the spectral efficiency of wireless communications is already close to its fundamental bounds, a significant increase in spatial efficiency is required to meet future traffic demands. Device-to-device (D2D) communications provide such an increase by allowing nearby u…

<title>Statistical bandwidth allocation for multiservice networks</title>

2002

Multiservice networks will carry di erent kinds of applications in the near future. Bandwidth requirements change rapidly, and the network resource management will play an important role to guarantee the use of the limited resources in the most eAEcient way. We approach the channel capacity allocation problem by developing an SLA (Service Level Agreement) based channel allocation method. In our model, the channel may be wired or wireless, so this method can be adapted in multi-technique networks. The algorithm allocates resources to several di erent service classes via several di erent capacity routes. Service provider perfroms optimization by allocating data rate in such a way that the sat…

(-)-Isosteviol as a Versatile Ex-Chiral-Pool Building Block for Organic Chemistry (Eur. J. Org. Chem. 25/2013)

2013

ChemInform Abstract: (-)-Isosteviol as a Versatile Ex-Chiral-Pool Bulding Block for Organic Chemistry

2013

Channel Switching Protocols Hinder the Transition to IP World: The Pentagon Story

2019

In this paper, we target the strategy for telecommunications architectures during the transition to the IP-only models. The paper discusses the shifting from circuit switching to packet switching in telecommunications. Particularly, we analyze the coexistence of circuit switching and packet switching technologies in American military communications where each warfare object should have own IP address. The paper discusses the role of multifunction Soft Switches (MFSS). This Soft Switch plays the role of a media gateway between TDM channels and IP channels. As a case, we are passing through the transformation from SS7 signaling to internet protocol, ISDN-based government Defense Red Switch Ne…

Optical systems for non-invasive cardiovascular biosensing

2005

Three portable prototype devices for cardiovascular biosensing based on reflection-type photoplethysmography (PPG) principle have been designed and clinically tested. The single-channel PPG finger sensor provides real-time measurements with fast calculation of the mean single-period PPG signal shape ("cardiovascular fingerprint", potentially useful for recognition). The dual-channel PPG system gives additional possibility to monitor on-line the arterial pulse wave transit time and its responses to physical exercises. The four-channel PPG system proved to be applicable for fast detection of cardiovascular pathologies, e.g. arterial occlusions in extremities. Design principles and software al…

<title>Photonic vascular diagnostics by four-channel photoplethysmography</title>

2005

A four-channel photoplethysmography device was designed and built at University of Latvia to detect signals from different body parts and to analyze the signal shapes. The device consists of optical contact probes, interface, and a standard PC. Clinical tests were performed with occlusion patients having vascular problems at arm or leg arteries. Results showed significant difference in the pulse wave transit time in occluded and nonoccluded part of the body.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An Investigation of Security and Privacy for Human Bond Communications

2017

ROS/Gazebo Based Simulation of Co-operative UAVs

2019

UAVs can be assigned different tasks such as e.g., rendez-vous and space coverage, which require processing and communication capabilities. This work extends the architecture ROS/Gazebo with the possibility of simulation of co-operative UAVs. We assume UAV with the underlying attitude controller based on the open-source Ardupilot software. The integration of the co-ordination algorithm in Gazebo is implemented with software modules extending Ardupilot with the capability of sending/receiving messages to/from drones, and executing the co-ordination protocol. As far as it concerns the simulation environment, we have extended the world in Gazebo to hold more than one drone and to open a specif…

Active spike transmission in the neuron model with a winding threshold manifold

2012

International audience; We analyze spiking responses of excitable neuron model with a winding threshold manifold on a pulse stimulation. The model is stimulated with external pulse stimuli and can generate nonlinear integrate-and-fire and resonant responses typical for excitable neuronal cells (all-or-none). In addition we show that for certain parameter range there is a possibility to trigger a spiking sequence with a finite number of spikes (a spiking message) in the response on a short stimulus pulse. So active transformation of N incoming pulses to M (with M>N) outgoing spikes is possible. At the level of single neuron computations such property can provide an active "spike source" comp…