Design and analysis of LTE-WLAN wireless router with QOS preservation

Future wireless networks are envisioned to embrace a higher level of heterogeneity whereby different wireless technologies such as Long Term Evolution UMTS (LTE), Wireless Local Area Network (WLAN), WCDMA/HSPA, WiMAX, etc, not only will coexist but will also cooperate more closely. This is motivated by the fact that several complementary characteristics exist between these technologies. For example, one technology can be used as access technology while the other can be used for backhaul. To interconnect two or more wireless technologies, the usage of routing device is inevitable. In order to preserve the Quality of Service (QoS) across these technologies which come with different QoS definitions, a more comprehensive approach is required to preserve QoS across two diverse wireless technologies i.e. Enhanced Distributed Coordination Function (EDCA) for WLAN and Uplink/Downlink packet scheduling for LTE. WLAN is reasonably priced, easy to deploy and has been enjoying a wide market acceptance especially in the indoor. The LTE is expected to be the dominant 4G cellular technology. However it will take some time before LTE can attain the same level of adoption as what WLAN has achieved especially in the consumer market. The main objective of this research project is to design an access router that enables the interworking between WLAN and LTE with QoS preservation. First, the performance of both WLAN and LTE radio interfaces are investigated independently in terms of the data rates, user/system throughput, effect of multiple access and spectral efficiency. Next, different approaches and schemes which facilitate QoS preservation between WLAN and LTE over the router are investigated and evaluated in terms of different performance metrics (voice Mean Opinion Score, video delay, video traffic received, video jitter, video packet loss rate). The design and analysis of the performance are carried out through simulation as the only feasible approach to accomplish this work. OPNET Modeler is used to model the LTE-WLAN router as well as to perform the analysis. The results of this research verify the feasibility of the proposed router architecture and the interworking paradigm. The elegance of the proposed router implementation is that it does not require massive change in the existing wireless systems, LTE and WLAN to preserve the QoS. The results of the performance analysis show that it is crucial to have a QoS preservation mechanism in the router IP layer at any potential congestion point in the wireless network, to ensure that delay-sensitive and loss-sensitive applications, such as real-time video and voice, pass through unimpeded, relative to the loss-tolerant and delay-tolerant data applications. The comparison of the designed IP QoS preservation scheme namely, Priority Queuing without Block Acknowledgement (PQ noBA) shows that it can support 50% more multimedia application across the router than the other scheme

Language ideologies in the female Brazilian diaspora in Serbia: interdisciplinary perspective ; Языковые идеологии в женской бразильской диаспоре в Сербии: междисциплинарная перспектива

Predmet ovog rada su jezičke ideologije pripadnica brazilske dijaspore u Srbiji, izvornih govornica portugalskog jezika, koje su u braku ili vanbračnoj zajednici sa Srbima, izvornim govornicima srpskog jezika. Jezičke ideologije su raširene u svim društvima, u kojima utiču na jezičko ponašanje govornika i govornica, reprodukuju se, prenose se, održavaju se i menjaju, često sasvim implicitno, ali i eksplicitno, kroz iznošenje stavova prema jeziku. Zato je proučavanje stavova prema jeziku jedan od najboljih načina da se identifikuju jezičke ideologije koje preovladavaju u određenoj govornoj zajednici. U ovom istraživanju polazimo od te međupovezanosti stavova prema jeziku i jezičkih ideologija i analiziramo stavove ispitanica prema manjinskom i većinskom jeziku, kao i prema nekim drugim jezičkim varijetetima i sa njima povezanim pojmovima...This paper focuses on the linguistic ideologies of female members of the Brazilian diaspora in Serbia, native speakers of the Portuguese language, who are married to or in a domestic partnership with Serbs, native speakers of the Serbian language. Language ideologies are widespread in every society, affecting the linguistic behaviour of speakers, being reproduced, transmitted, maintained, and changed, often quite implicitly, as well as explicitly, by expressing attitudes toward language. That is why studying attitudes towards language is one of the best ways to identify linguistic ideologies that are dominant in a specific speech community. This study starts off with this interconnectedness of attitudes towards language and language ideologies and analyzes the attitudes of respondents towards the minority and majority languages, as well as towards a few other language varieties and terms related to these..