ARTICLE | doi:10.20944/preprints201712.0179.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: cognitive radio; cognitive vehicular networks; spectrum sensing; sensing/reporting channel; correlated rayleigh fading channel; hard fusion
Online: 25 December 2017 (10:42:53 CET)
An explosive growth in vehicular wireless services and applications gives rise to spectrum resource starvation. Cognitive radio has been used to vehicular networks to mitigate the impending spectrum starvation problem by allowing vehicles to fully exploit spectrum opportunities unoccupied by licensed users. Efficient and effective detection of licensed user is a critical issue to realize cognitive radio applications. However, spectrum sensing in vehicular environments is a very challenging task due to vehicles mobility. For instance, vehicle mobility has a large effect on the wireless channel, thereby impacting the detection performance of spectrum sensing. Thus, gargantuan efforts have been made in order to analyze the fading properties of mobile radio channel in vehicular environments. Indeed, numerous studies have demonstrated that the wireless channel in vehicular environments can be characterized by a temporally correlated Rayleigh fading. In this paper, we focus on energy detection for spectrum sensing and a counting rule for cooperative sensing based on Neyman-Pearson criteria. Further, we go into the effect of the sensing and reporting channels condition on spectrum sensing performance under temporally correlated Rayleigh sensing channel. For local and cooperative sensing, we derive some alternative expressions for average probability of miss detection. The pertinent numerical and simulating results are provided to further validate our theoretical analyses under a variety of scenarios.
CASE REPORT | doi:10.20944/preprints202002.0199.v1
Subject: Social Sciences, Business And Administrative Sciences Keywords: Ecotourism; Sustainability; Island Tourism; Penghu National Scenic Area; Tourist Service System
Online: 15 February 2020 (14:45:47 CET)
In order to increase the number of tourism in ecotourism, enhance the ecotourism attractions. It is essential to construct the ecotourism service system for the Penghu National Scenic Area because the ecology system is sensitive and frangible. This study adopts the Fuzzy Delphi method and Analytic Hierarchy Process (AHP) to establish an index framework of ecotourism service system of Penghu National Scenic Area. The results indicated that there are 4 dimensions which include 21 factors service attributes are identified as the service system for traveling. The findings are concluded as follows:(1)the security management capability is the main principle for ecotourism service system;(2)the ecological diversity is fundamental for the marine environment and the core resource for ecotourism;(3)the transportation capacity and environmental quality need to improve; (4)the marine environmental resources is the most important item for sound ecotourism development; (5)the enhancement of the operation willingness of local communities can promote ecotourism development;(6)the natural resources should be protected to provide an ideal recreational environment for ecotourism;(7)the development of ecotourism needs to support local conservation to achieve sustainability. The perspectives of sustainability and service system are involved to support the value of this study, which can continuously sustain Penghu archipelago.