The paradigm of dynamic shared access aims to provide flexible spectrum usage. Recently, Federal Communications Commission (FCC) has proposed a new dynamic spectrum management framework for the sharing of a 3.5 GHz (3550–3700 MHz) federal band, called a citizen broadband radio service (CBRS) band, which is governed by spectrum access system (SAS). It is the responsibility of SAS to manage the set of CBRS-SAS users. The set of users are classified in three tiers: incumbent access (IA) users, primary access license (PAL) users and the general authorized access (GAA) users. In this article, dynamic channel assignment algorithm for PAL and GAA users is designed with the goal of maximizing the transmission rate and minimizing the total cost of GAA users accessing PAL reserved channels. We proposed a new mathematical model based on multi-objective optimization for the selection of PAL operators and idle PAL reserved channels allocation to GAA users considering the diversity of PAL reserved channels’ attributes and the diversification of GAA users’ business needs. The proposed model is estimated and validated on various performance metrics through extensive simulations and compared with existing algorithms such as Hungarian algorithm, auction algorithm and Gale–Shapley algorithm. The proposed model results indicate that overall transmission rate, net cost and data-rate per unit cost remain the same in comparison to the classical Hungarian method and auction algorithm. However, the improved model solves the resource allocation problem approximately up to four times faster with better load management, which validates the efficiency of our model.

Wireless multimedia sensor networks (WMSNs) generate a huge amount of multimedia data. Congestion is one of the most challenging open issues in WMSNs. Congestion causes low throughput, high packet loss and low energy efficiency. Congestion happens when the data carried by the network surpasses the available capacity. This article presents an energy-efficient distributed congestion control protocol (DCCP) to mitigate congestion and improve end-to-end delay. Compared to the other protocols, the DCCP protocol proposed in this article can alleviate congestion by intelligently selecting the best path. First, congestion is detected by using two congestion indicators. Second, each node aggregates the received data and builds a traffic congestion map. The traffic congestion map is used to calculate the best path. Therefore, the traffic is balanced on different routes, which reduces the end-to-end delay. Finally, a rate controller is designed to prevent congestion in the network by sending a congestion notification message to a source node. After receiving a congestion notification message, the source node immediately adjusts its transmission rate. Experimental results based on raspberry pi sensor nodes show that the proposed DCCP protocol significantly improves network performance and is superior to existing modern congestion control protocols.

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In Pakistan, power outages have become frequent over the past two decades, due to a continuing energy crisis. Reliance on machines for thermal comfort of buildings has led to high energy demands of the increasing population. The negative impacts of artificial environments have, also, diminished the sense of place, biophilia and cultural values. Moreover, globalization has standardized the built environments, causing a lack of regional identity and an absence of climate sensitivity in design. Keeping all these issues in focus, this article re-examines the fundamental aspects of traditional architecture and aims to stimulate architects and designers to create sustainable and life-enriching designs, which are appropriate for contemporary times. In this research, the first two levels of Deep Beauty functional and typological, are used as a conceptual framework for sustainable design. For this, research findings of the book, A Pattern Language: Towns, Buildings, Construction, are employed as a conceptual guide, for analyzing a representative of a traditional courtyard house. In conjunction with the theoretical underpinnings of the Deep Beauty framework, the analysis utilizes photographs, drawings, and diagrams to support the arguments. The research shows that the traditional courtyard house possesses numerous attributes of sustainable design, which can be incorporated into contemporary house design.