Search results for "Telecommunication"
showing 10 items of 1769 documents
Effects of Temperature and Humidity on Radio Signal Strength in Outdoor Wireless Sensor Networks
2015
Many wireless sensor networks operating outdoors are exposed to changing weather conditions, which may cause severe degradation in system performance. Therefore, it is essential to explore the factors affecting radio link quality in order to mitigate their impact and to adapt to varying conditions. In this paper, we study the effects of temperature and humidity on radio signal strength in outdoor wireless sensor networks. Experimental measurements were performed using Atmel ZigBit 2.4GHz wireless modules, both in summer and wintertime. We employed all the radio channels specified by IEEE 802.15.4 for 2.4GHz ISM frequency band with two transmit power levels. The results show that changes in …
Towards proactive context-aware self-healing for 5G networks
2017
In this paper, we suggest a new research direction and a future vision for Self-Healing (SH) in Self-Organizing Networks (SONs). The problem we wish to solve is that traditional SH solutions may not be sufficient for the future needs of cellular network management because of their reactive nature, i.e., they start recovering after detecting already occurred faults instead of preparing for possible future faults in a pre-emptive manner. The detection delays are especially problematic with regard to the zero latency requirements of 5G networks. To address this problem, existing SONs need to be upgraded from reactive to proactive response. One of the dimensions in SH research is to employ more…
Towards Mitigating the Impact of UAVs on Cellular Communications
2018
The next generation of Unmanned Aerial Vehicles (UAVs) will rely on mobile networks as a communication infrastructure. Several issues need to be addressed to enable the expected potentials from this communication. In particular, it was demonstrated that flying UAVs perceive a high number of base stations (BSs), consequently causing more interferences on non-serving BSs. This unfortunately results in decreased throughput for ground user equipments (UEs) already connected. Such a problem could be a limiting factor for mobile network-enabled UAVs, due to its consequences on the quality of experience (QoE) of served UEs. This underpins the focus of this article, wherein the effect of UAVs' comm…
Mehr als Musik: Die sieben Dimensionen des Eurovision Song Contests
2008
"Der Eurovision Song Contest (ESC) ist der weltweit größte internationale Wettbewerb für populäre Musik und das erfolgreichste Fernsehunterhaltungsprogramm in Europa. Obwohl der ESC ursprünglich das Ziel verfolgte, die Entstehung neuer Lieder zu fördern, handelte es sich doch stets um ein von den Fernsehanstalten inszeniertes Medienereignis, das erst nachrangig musikökonomischen Zwecken dient. Für das Publikum ist der ESC auf Grund seiner Periodizität, seiner spezifischen Programmstruktur und nicht zuletzt des Zugehörigkeitsgefühls der Zuschauer, das auf Schemata nationaler und kultureller Identifikation beruht, zu einem hochgradig ritualisierten Medienereignis geworden. Seine Bedeutung geh…
Reducing the Time to Detect Cyber Attacks : Combining Attack Simulation With Detection Logic
2021
Cyber attacks have become harder to detect, causing the average detection time of a successful data breach to be over six months and typically costing the target organization nearly four million dollars. The attacks are becoming more sophisticated and targeted, leaving unprepared environments easy prey for the attackers. Organizations with working antivirus systems and firewalls may be surprised when they discover their network has been encrypted by a ransomware operator. This raises a serious question, how did the attacks go undetected? The conducted research focuses on the most common pitfalls regarding late or even non-existent detection by defining the root cause behind the failed detec…
Overview of Power Electronic Switches: A Summary of the Past, State-of-the-Art and Illumination of the Future.
2020
As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progr…
Anonymization as homeomorphic data space transformation for privacy-preserving deep learning
2021
Industry 4.0 is largely data-driven nowadays. Owners of the data, on the one hand, want to get added value from the data by using remote artificial intelligence tools as services, on the other hand, they concern on privacy of their data within external premises. Ideal solution for this challenge would be such anonymization of the data, which makes the data safe in remote servers and, at the same time, leaves the opportunity for the machine learning algorithms to capture useful patterns from the data. In this paper, we take the problem of supervised machine learning with deep feedforward neural nets and provide an anonymization algorithm (based on the homeomorphic data space transformation),…
Engine/Transmission Matching
2014
This chapter deals with the forecasting of vehicle performance on the road, according to the installed engine. It begins with Section 1, which shows the calculation of the resistance to motion, that is, the forces that the vehicle must overcome to advance on flat roads and uphill. The calculation excludes accidental resistance in curves because it is not essential for predicting the behavior of the vehicle on the road. Section 2 begins with the power characteristic, the forecast by traction–speed and power–speed diagrams, calculation of gear ratios, and then passing to the limits to the estimated acceleration, feature consumption, and distance. This chapter concludes with a section on the d…
On the effects of transmit power control on the energy consumption of WiFi network cards
2009
Transmit power control has been largely proposed as a solution to improve the performance of packet radio systems in terms of increased throughput, spatial reuse and battery lifetime for mobile terminals. However, the benefits of transmit power control schemes on these different performance figures may strongly depend on the employed PHY technology and channel access mechanism. In this paper, we focus on the effects of power control on the energy consumption of WiFi network cards. By means of several experimental tests carried out under different operation conditions and modulation schemes, we try to justify why the reduction of the transmission power has a marginal effect on the overall en…