Reo is a channel-based coordination model whose operational semantics is given by Constraint Automata (CA). Quantitative Constraint Automata extend CA (and hence, Reo) with quantitative models to capture such non-functional aspects of a system’s behaviour as delays, costs, resource needs and consumption, that depend on the internal details of the system. However, the performance of a system can...

In this paper, we study short-term fairness in distributed, contention-based wireless medium access control (MAC) protocols. While most MAC protocols provide fairness among contending stations in the long term, they are not fair over shorter time scales. We rst demonstrate short-term unfairness of CSMA/CA using packet-level traces collected from an in-bulding wireless LAN network. We also analy...

With the rapid development of social economy, sustainable use land is becoming more and important. Based on GIS remote sensing technology, work processed status data Qingzhen in 2016 2020, obtained dynamic change during period, analyzed its structure, quantity degree. Finally, we used CA-Markov model to obtain flow direction probability type. Results showed that rate non-agricultural increase, ...

The land use cover change and its modeling approach has recently been considered by the scientific community to observe environmental changes. Remote Sensing Geographical Information System (GIS) give major techniques which can be useful in analysis at town locale as well city levels. RS data from Thematic Mapper sensor of 1998, 2002, 2010, 2014, 2018, Operational Land Imager 2018 were used for...

The evaluation of habitat quality and its genesis is great significance to ecological protection the watershed. Based on land use data, Digital Elevation Model (DEM), road network data population Cellular Automata (CA)-Markov model InVEST were used analyzed change in Wanhe Watershed, predicting 2025. this, degree degradation 2000, 2005, 2010, 2015, 2020, 2025 predicted analyzed, combined with p...

In cognitive radio networks, channel aggregation (CA) and channel fragmentation (CF) techniques have been proposed to enhance the spectrum utilization. While most of the literature studies CA and CF independently, in this paper we combine CA and CF innovatively and present a new spectrum sharing strategy named CAF (Channel Aggregation and Fragmentation). We elaborate on the proposed CAF strateg...