Network-Assisted Resource Allocation with Quality and Conflict Constraints for V2V Communications

The 3rd Generation Partnership Project (3GPP) has recently established in Rel. 14 a network-assisted resource allocation scheme for vehicular broadcast communications. Such novel paradigm is known as vehicle--to--vehicle (V2V) \textit{mode-3} and consists in eNodeBs engaging only in the distribution of sidelink subchannels among vehicles in coverage. Thereupon, without further intervention of the former, vehicles will broadcast their respective signals directly to their counterparts. Because the allotment of subchannels takes place intermittently to reduce signaling, it must primarily be conflict-free in order not to jeopardize the reception of signals. We have identified four pivotal types of allocation requirements that must be guaranteed: one quality of service (QoS) requirement and three conflict conditions which must be precluded in order to preserve reception reliability. The underlying problem is formulated as a maximization of the system sum-capacity with four types of constraints that must be enforced. In addition, we propose a three-stage suboptimal approach that is cast as multiple independent knapsack problems (MIKPs). We compare the two approaches through simulations and show that the latter formulation can attain acceptable performance at lesser complexity

Poster Abstract: Hierarchical Subchannel Allocation for Mode-3 Vehicle-to-Vehicle Sidelink Communications

In V2V Mode-3, eNodeBs assign subchannels to vehicles in order for them to periodically broadcast CAM messages \cite{b2}. A crucial aspect is to ensure that vehicles in the same cluster will broadcast in orthogonal time subchannels\footnote{A subchannel is a time-frequency resource chunk capable of sufficiently conveying a CAM message.} to avoid conflicts. In general, resource/subchannel allocation problems can be represented as weighted bipartite graphs. However, in this scenario there is an additional time orthogonality constraint which cannot be straightforwardly handled by conventional graph matching methods \cite{b3}. Thus, in our approach the mentioned constraint has been taken into account. We also perform the allocation task in a sequential manner based on the constrainedness of each cluster. To illustrate the gist of the problem, in Fig. 1 we show two partially overlapping clusters where a conflict between vehicles $V_8$ and $V_{10}$ is generated as the allotted subchannels are in the same subframe

Poster: Resource Allocation with Conflict Resolution for Vehicular Sidelink Broadcast Communications

In this paper we present a graph-based resource allocation scheme for sidelink broadcast V2V communications. Harnessing available information on geographical position of vehicles and spectrum resources utilization, eNodeBs are capable of allotting the same set of sidelink resources to different vehicles distributed among several communications clusters. Within a communications cluster, it is crucial to prevent time-domain allocation conflicts since vehicles cannot transmit and receive simultaneously, i.e., they must transmit in orthogonal time resources. In this research, we present a solution based on a bipartite graph, where vehicles and spectrum resources are represented by vertices whereas the edges represent the achievable rate in each resource based on the SINR that each vehicle perceives. The aforementioned time orthogonality constraint can be approached by aggregating conflicting vertices into macro-vertices which, in addition, reduces the search complexity. We show mathematically and through simulations that the proposed approach yields an optimal solution. In addition, we provide simulations showing that the proposed method outperforms other competing approaches, specially in scenarios with high vehicular density.Comment: arXiv admin note: substantial text overlap with arXiv:1805.0655

Free monadic Tarski and MMI3-algebras

MMI3-algebras are a generalization of the monadic Tarski algebras as defined by A. Monteiro and L. Iturrioz, and a particular case of the MMIn+1-algebras defined by A. Figallo. They can also be seen as monadic three-valued £ukasiewicz algebras without a first element. By using this point of view, and the free monadic extensions, we construct the free MMI3-algebras on a finite number of generators, and indicate the coordinates of the generators. As a byproduct, we also obtain a construction of the free monadic Tarski algebras.Fil: Entizne, Rosana V.. Universidad Nacional del Sur. Departamento de Matemática; ArgentinaFil: Monteiro, Luiz F.. Universidad Nacional del Sur. Departamento de Matemática; ArgentinaFil: Savini, Sonia M.. Universidad Nacional del Sur. Departamento de Matemática; ArgentinaFil: Viglizzo, Ignacio Dario. Universidad Nacional del Sur. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentin

A history of education in relation to the development of the Protectorate of Northern Nigeria 1900-1919, with special reference to the work of Hanns Vischer

Mission societies provided most education in British West African dependencies in 1900. Education followed a different pattern in the Protectorate of Northern Nigeria because Lugard, short of money and men, preserved the Mohammedan emirates in the system known as Indirect Rule, Mohammedan dislike of Christianity and his own insecurity led Lugard to promise non-interference with the Mohammedan religion, a promise later used to exclude missionaries from emirates. Indirect Rule requires at least educated governing and clerical classes. Lugard disliked on principle Government-supported mission education for Mohammedans, and he feared from past experience the disruptive effect on the social fabric of African life of mission stations. Yet financial difficulties compelled his interest in Dr. Miller's (C.M.S.) Zaria Schools plan. This plan was too secular by C.M.S. standards end yet condemned by Administration for over-great religious bias. Girouard, Lugard's successor, determined on a Government Education Department as the only alternative, and he seconded Vischer - a political officer by temperament and experience sympathetic to Indirect Rule - to Education. Vischer wished to lessen the strain of the culture-clash in Northern Nigeria and to use "adapted" education as part of the evolutionary process whereby Indirect Rule would eventually give way to self-government. Slow, sure progress was made in education from 1909 to 1914, Mohammedan suspicion was lulled. Meanwhile some emirates had become Native Administrations with Treasuries, and mission expansion was considered more dangerous than ever to the political experiment. Education, religion and politics were so bound together any action resulted in a complex chain of reactions. After the amalgamation in 1914 of Northern and Southern Nigeria, the Colonial Office insisted on Vischer's education system being safeguarded in the Education Ordinance of 1916 and by subsequent legislation. On political groups this attitude was acceptable to many Residents. War checked progress. Yet the Education Department opened new schools and in its 1918 Report "adapted" education was shown to be an evolutionary process rather than a static method. From 1923 to 1939 Vischer was secretary to the Colonial Office's Advisory Council on Education, and from 1926 to 1945 to the International African Institute. He preached the doctrine of mutual enrichment through culture-clash without the disruption of either society. The ultimate choice in West Africa lay, he realized, with the African.<p

Non-linear optics with two trapped atoms

We show theoretically that two atomic dipoles in a resonator constitute a non-linear medium, whose properties can be controlled through the relative position of the atoms inside the cavity and the detuning and intensity of the driving laser. We identify the parameter regime where the system operates as a parametric amplifier, based on the cascade emission of the collective dipole of the atoms, and determine the corresponding spectrum of squeezing of the field at the cavity output. This dynamics could be observed as a result of self-organization of laser-cooled atoms in resonators.Comment: 11 pages, 8 figure

Introduction to Financial Mathematics Course

The teaching of financial mathematics at the university level has become more common in the past decade. It is crucial that young officers of our military system be aware of its intricacies in order to present themselves before the world with a more rounded and broader literacy