scholarly journals Numerical simulation of effective light transmission through a photonic memory cell

2021 ◽  
Vol 2086 (1) ◽  
pp. 012090
Author(s):  
M E Makarov ◽  
A A Sapegin ◽  
R T Minnullin

Abstract This paper is devoted to numerical simulation of a non-volatile photonic memory cell based on phase-change material Ge2Sb2Te5. The parameters of light propagation are presented for both crystalline and amorphous Ge2Sb2Te5 phases. The cell structure is optimized for a single TE-mode regime that is suitable for short- and long-distance communication lines.

Electrum ◽  
2021 ◽  
Vol 28 ◽  
pp. 151-161
Author(s):  
Michał Marciak

The aim of this paper is to provide an overview of the geopolitical status of the Upper Tigris area in antiquity, with a special focus on the period between ca. 401 BCE and the 6th century CE. Despite the popular impression that this area had a distinctly Armenian character, a closer look at its history shows that it was rather a territory with many local geopolitical entities that many neighboring countries periodically fought to possess. This area was strategically significant as a transit region located on the crossroads of important long-distance communication lines. Likewise, its natural resources were undoubtedly crucial to the neighboring countries. Indeed, powerful neighbors around the Upper Tigris area, including Armenia, the Iranian kingdoms of the Parthians and Sasanians, and Rome, sought to control this area, which was often located on the fringes of their states and as such was inevitably doomed to be contested by these empires onmany occasions. This situation can be acutely seen in the conflict between Rome and the Iranian kingdoms of the Parthians and Sasanians, when northern Mesopotamia became a real battleground between the competing empires. In particular, the paper will sketch the development of the geopolitical status of several small geopolitical entities in this region—Sophene, Osrhoene, Gordyene, and Adiabene.


Electronics ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 940
Author(s):  
Nicoleta Cristina Gaitan

Recent market studies show that the market for remote monitoring devices of different medical parameters will grow exponentially. Globally, more than 4 million individuals will be monitored remotely from the perspective of different health parameters by 2023. Of particular importance is the way of remote transmission of the information acquired from the medical sensors. At this time, there are several methods such as Bluetooth, WI-FI, or other wireless communication interfaces. Recently, the communication based on LoRa (Long Range) technology has had an explosive development that allows the transmission of information over long distances with low energy consumption. The implementation of the IoT (Internet of Things) applications using LoRa devices based on open Long Range Wide-Area Network (LoRaWAN) protocol for long distances with low energy consumption can also be used in the medical field. Therefore, in this paper, we proposed and developed a long-distance communication architecture for medical devices based on the LoRaWAN protocol that allows data communications over a distance of more than 10 km.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Filip Rozpędek ◽  
Kyungjoo Noh ◽  
Qian Xu ◽  
Saikat Guha ◽  
Liang Jiang

AbstractWe propose an architecture of quantum-error-correction-based quantum repeaters that combines techniques used in discrete- and continuous-variable quantum information. Specifically, we propose to encode the transmitted qubits in a concatenated code consisting of two levels. On the first level we use a continuous-variable GKP code encoding the qubit in a single bosonic mode. On the second level we use a small discrete-variable code. Such an architecture has two important features. Firstly, errors on each of the two levels are corrected in repeaters of two different types. This enables for achieving performance needed in practical scenarios with a reduced cost with respect to an architecture for which all repeaters are the same. Secondly, the use of continuous-variable GKP code on the lower level generates additional analog information which enhances the error-correcting capabilities of the second-level code such that long-distance communication becomes possible with encodings consisting of only four or seven optical modes.


2013 ◽  
Vol 59 (4) ◽  
pp. 483-497 ◽  
Author(s):  
D. Prakash ◽  
P. Ravikumar

Abstract In this paper, transient analysis on heat transfer across the residential building roof having various materials like wood wool, phase change material and weathering tile is performed by numerical simulation technique. 2-dimensional roof model is created, checked for grid independency and validated with the experimental results. Three different roof structures are included in this study namely roof with (i). Concrete and weathering tile, (ii). Concrete, phase change material and weathering tile and (iii). Concrete, phase change material, wood wool and weathering tile. Roof type 3 restricts 13% of heat entering the room in comparison with roof having only concrete and weathering tile. Also the effect of various roof layers’ thickness in the roof type 3 is investigated and identified that the wood wool plays the major role in arresting the entry of heat in to the room. The average reduction of heat is about 10 % for an increase of a unit thickness of wood wool layer.


1999 ◽  
Vol 09 (01n02) ◽  
pp. 125-132
Author(s):  
GEUN-TAEK RYU ◽  
DAE-SUNG KIM ◽  
DAE-YOUNG LEE ◽  
SUNG-HWAN HAN ◽  
HYEON-DEOK BAE

The choice of the adaptive gain is important to the performance of LMS-based adaptive filters. Depending on application areas, the realization structure of the filters is also important. This letter presents an adaptive lattice algorithm which adjusts the adaptive gain of LMS using fuzzy if-then rules determined by matching input and output variables during adaptation procedure. In each lattice filter stage, this filter adjusts the adaptive gain as the output of the fuzzy logic which has two input variables, normalized squared forward prediction error and one step previous adaptive gain. The proposed algorithm is applied to echo canceling problem of long distance communication channel. The simulation results are compared with NLMS on TDL and lattice structures.


Sign in / Sign up

Export Citation Format

Share Document