Cell Selection in Wireless Two-Tier Networks: A Context-Aware Matching Game

The deployment of small cell networks is seen as a major feature of the next generation of wireless networks. In this paper, a novel approach for cell association in small cell networks is proposed. The proposed approach exploits new types of information extracted from the users' devices and environment to improve the way in which users are assigned to their serving base stations. Examples of such context information include the devices' screen size and the users' trajectory. The problem is formulated as a matching game with externalities and a new, distributed algorithm is proposed to solve this game. The proposed algorithm is shown to reach a stable matching whose properties are studied. Simulation results show that the proposed context-aware matching approach yields significant performance gains, in terms of the average utility per user, when compared with a classical max-SINR approach.Comment: 11 pages, 11 figures, Journal article in ICST Wireless Spectrum, 201

An F-statistic based multi-detector veto for detector artifacts in continuous-wave gravitational wave data

Continuous gravitational waves (CW) are expected from spinning neutron stars with non-axisymmetric deformations. A network of interferometric detectors (LIGO, Virgo and GEO600) is looking for these signals. They are predicted to be very weak and retrievable only by integration over long observation times. One of the standard methods of CW data analysis is the multi-detector F-statistic. In a typical search, the F-statistic is computed over a range in frequency, spin-down and sky position, and the candidates with highest F values are kept for further analysis. However, this detection statistic is susceptible to a class of noise artifacts, strong monochromatic lines in a single detector. By assuming an extended noise model - standard Gaussian noise plus single-detector lines - we can use a Bayesian odds ratio to derive a generalized detection statistic, the line veto (LV-) statistic. In the absence of lines, it behaves similarly to the F-statistic, but it is more robust against line artifacts. In the past, ad-hoc post-processing vetoes have been implemented in searches to remove these artifacts. Here we provide a systematic framework to develop and benchmark this class of vetoes. We present our results from testing this LV-statistic on simulated data.Comment: 2 pages, 1 figure, to be published in Proceedings of Statistical Challenges in Modern Astronomy V, Springer 201

Exploring the Nexus Between Culture, Values, Institutions, Happiness and Philanthropy: A Global Evidence

The main aim of this study was to investigate the impact of culture, values, institutions, and happiness on the world’s philanthropy. Culture is measured by Hofstede index (i.e. individualism-collectivism, masculinity-femininity, long and short-run orientation, uncertainty avoidance, power distance, and indulgence-restraint). The measurement of value is WVS (World Value Survey) and it consists of the emotion of happiness, active/ inactive membership of a church or religious organization, important in life; religion, confidence on charitable/ humanitarian organization and active/ inactive membership of charitable/ humanitarian organization. Institutions are measured by WGI (World Governance Indicators) and it consists of corruption, regulatory quality, accountability and voice, rule of law, political stability and government effectiveness, the sub-variables of happiness (index) are social support, freedom to take decisions and generosity and world’s philanthropy is measured by CAF (Charitable Aid Foundation) world giving index. We have gathered panel data (from the period 2010 to 2014) of CAF index, happiness index and WGI of 62 countries and cross-sectional data of CAF index, Hofstede index, WGI, happiness index and WVS of 24 countries. The result (of panel data) shows that there is a significant relation of WGI, social support and freedom of choice with CAF index whereas there is an insignificant connection between generosity and CAF index. The findings (of cross-sectional data of all factors combined) shows that there is a relation of the Hofstede index and happiness index with the CAF index while there is no linkage of WGI and WVS with the CAF index. The study suggests that charitable organizations should personify their value in order to build trust among the public. Countries should improve their governance because this will lead to equality and by doing this countries will also manage their resources efficiently and effectively. Keywords: Culture, Value, Institution, Happiness, Philanthropy, Cross Country DOI: 10.7176/RHSS/10-3-05 Publication date: February 29th 2020

A Colonel Blotto Game for Interdependence-Aware Cyber-Physical Systems Security in Smart Cities

Smart cities must integrate a number of interdependent cyber-physical systems that operate in a coordinated manner to improve the well-being of the city's residents. A cyber-physical system (CPS) is a system of computational elements controlling physical entities. Large-scale CPSs are more vulnerable to attacks due to the cyber-physical interdependencies that can lead to cascading failures which can have a significant detrimental effect on a city. In this paper, a novel approach is proposed for analyzing the problem of allocating security resources, such as firewalls and anti-malware, over the various cyber components of an interdependent CPS to protect the system against imminent attacks. The problem is formulated as a Colonel Blotto game in which the attacker seeks to allocate its resources to compromise the CPS, while the defender chooses how to distribute its resources to defend against potential attacks. To evaluate the effects of defense and attack, various CPS factors are considered including human-CPS interactions as well as physical and topological characteristics of a CPS such as flow and capacity of interconnections and minimum path algorithms. Results show that, for the case in which the attacker is not aware of the CPS interdependencies, the defender can have a higher payoff, compared to the case in which the attacker has complete information. The results also show that, in the case of more symmetric nodes, due to interdependencies, the defender achieves its highest payoff at the equilibrium compared to the case with independent, asymmetric nodes