Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
Water supply system has characteristics of non-linear, time-varying parameter, large time delay, so its mathematical model changes time by time. Water supply system widely use PID controller to keep constant pressure and PID controller need accurate mathematical model. The system that use PID controller is along with large overshoot, more adjusting time. Fuzzy controller don't need the accurate mathematical...
One of the main challenges in wireless networks is addressing the unreliability of the wireless links, and providing reliable transmissions. Two important sources of errors in wireless transmissions are noise and interference. In order to address the errors due to noise, forward error correction methods can be used, in which redundancy is added to the packets to detect and correct the bit errors....
As the popularity of wireless devices (e.g. smartphones and tablets) increases, watching videos over the Internet is becoming a main device application. Two important challenges in wireless communications are the unreliability of the wireless links and the interference among the wireless links. In order to exploit reliable video multicast, forward error correction and network coding can be used. In...
It has been proved that network coding can optimize routing in wireless networks. Thus, in deterministic routing, coding is considered as an important factor for route selection. While the existing deterministic routing solutions detect paths with coding opportunities based on the two-flow coding, little attention has been drawn to the multi-flow situation. Coding multiple flows directly, however,...
Since wireless local area network (WLAN) can support high transmission rate with low cost, the use of WLAN is increasing rapidly. The WLAN has become very congested, and in the dense environment, Overlapping BSS (basic set service) problem may be introduced, which will severely degrade the performance of the network. Transmission power control (TPC) of AP (Access Point) is considered as one of the...
This paper considers a pre-phase of spectrum sensing in cognitive radio networks (CRNs), which is about how to choose a channel for spectrum sensing. We take the time dimension, spectrum dimension, and spacial dimension into account and propose a sense-in-order model. In this model, each node maintains four states regarding each channel, based on the neighbors' shared information. We construct a state...
In this paper, we will illustrate a practice of pipeline process to maximize the parallelization of all possible interference-free relays in the broadcasting of wireless sensor networks (WSNs), in order to optimize the end-to-end delay performance in both the (synchronous) round-based systems and the (asynchronous) duty cycle systems. Broadcasting is one of the fundamental communications in WSNs....
Routing for Delay Tolerant Networks (DTNs) are challengeable for the continuously varied network environment. Most of existing DTN routing algorithms mainly focus on metrics such as delay, hop count and bandwidth, etc. Green communication is a new focus with the goal of saving energy by optimizing network performance and ultimately protecting the natural climate. In this paper, we present an Energy-efficient...
Cognitive radio is a key technology needed to better utilize the available spectrum more efficiently. In this paper, we consider the throughput optimization problem via spectrum allocation in the cognitive radio based wireless mesh networks (CR-based WMNs). Unlike prior research, we consider both the lower layer noncontinuous OFDM features and the physical interference model in designing our solution...
The channel assignment problem is one of the most important issues in cognitive radio networks (CRNs). Under a SINR-driven model, we consider channel assignments in a network using dynamic source routing (DSR). In this unicasting model, channel assignments are conducted in a relatively small scale of nodes, which are on the chosen route. In addition, we can make use of the route reply (RREP) message...
Cognitive radio networks (CRNs) promise to enable the next generation of communication networks. The channel assignment (CA) problem is one of the most important issues in CRNs. In this paper, our goal is to design highly efficient and localized protocols for CA. In addition, we want to maximize node connectivity after CA, which is important for packet delivery. To this end, we design two basic algorithms...
In a Wireless Local Area Network (WLAN), the Access Point (AP) selection of a client heavily influences the performance of its own and others. Through theoretical analysis, we reveal that previously proposed association protocols are not effective in maximizing the minimal throughput among all clients. Accordingly, we propose an online AP association strategy that not only achieves a minimal throughput...
The current access point (AP) association schemes in wireless LANs, such as IEEE 802.11, cause an unbalanced load which reduces the performance of both the entire network and individual users. Intensive studies were motivated to determine efficient methods of balancing loads among APs. Previous works provided either the heuristics without theoretical analysis on the performance, or algorithms that...
This paper addresses the problem of non-stationary signal noise suppression, represents the conception of wavelet transformation and puts forward two kinds of measurements to evaluate the effectiveness of noise suppression. Comparison experiments for noise suppression are made using Fourier analysis and Wavelet analysis. Simulation result shows that Wavelet analysis is more suitable for non-stationary...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.