A conditional compression distance that unveils insights of the genomic evolution

We describe a compression-based distance for genomic sequences. Instead of using the usual conjoint information content, as in the classical Normalized Compression Distance (NCD), it uses the conditional information content. To compute this Normalized Conditional Compression Distance (NCCD), we need a normal conditional compressor, that we built using a mixture of static and dynamic finite-context models. Using this approach, we measured chromosomal distances between Hominidae primates and also between Muroidea (rat and mouse), observing several insights of evolution that so far have not been reported in the literature.Comment: Full version of DCC 2014 paper "A conditional compression distance that unveils insights of the genomic evolution

Zero-Outage Cellular Downlink with Fixed-Rate D2D Underlay

Two of the emerging trends in wireless cellular systems are Device-to-Device (D2D) and Machine-to-Machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized by fixed and low transmission rates. D2D connections can be instrumental in localized aggregation of uplink M2M traffic to a more capable cellular device, before being finally delivered to the Base Station (BS). In this paper we show that a fixed M2M rate is an enabler of efficient Machine-Type D2D underlay operation taking place simultaneously with another \emph{downlink} cellular transmission. In the considered scenario, a BS $B$ transmits to a user $U$, while there are $N_M$ Machine-Type Devices (MTDs) attached to $U$, all sending simultaneously to $U$ and each using the same rate $R_M$. While assuming that $B$ knows the channel $B-U$, but not the interfering channels from the MTDs to $U$, we prove that there is a positive downlink rate that can always be decoded by $U$, leading to zero-outage of the downlink signal. This is a rather surprising consequence of the features of the multiple access channel and the fixed rate $R_M$. We also consider the case of a simpler, single-user decoder at $U$ with successive interference cancellation. However, with single-user decoder, a positive zero-outage rate exists only when $N_M=1$ and is zero when $N_M>1$. This implies that joint decoding is instrumental in enabling fixed-rate underlay operation.Comment: Revised versio

Network-Assisted Device-to-Device (D2D) Direct Proximity Discovery with Underlay Communication

Device-to-Device communications are expected to play an important role in current and future cellular generations, by increasing the spatial reuse of spectrum resources and enabling lower latency communication links. This paradigm has two fundamental building blocks: (i) proximity discovery and (ii) direct communication between proximate devices. While (ii) is treated extensively in the recent literature, (i) has received relatively little attention. In this paper we analyze a network-assisted underlay proximity discovery protocol, where a cellular device can take the role of: announcer (which announces its interest in establishing a D2D connection) or monitor (which listens for the transmissions from the announcers). Traditionally, the announcers transmit their messages over dedicated channel resources. In contrast, inspired by recent advances on receivers with multiuser decoding capabilities, we consider the case where the announcers underlay their messages in the downlink transmissions that are directed towards the monitoring devices. We propose a power control scheme applied to the downlink transmission, which copes with the underlay transmission via additional power expenditure, while guaranteeing both reliable downlink transmissions and underlay proximity discovery.Comment: Accepted for presentation at Globecom 201

Attracting Tourists in a creative way: the importance of Culture: The Porto’s 2001 European Capital of Culture experience

“Mega-events” describe happenings of international importance and high profile which have a major impact on the image of the host city. These events supply prestige to the host cities, and afford a profile related with the welcomed activities, and a important tourism potential. If mega events are of a sufficiently high quality then people will be prepared to travel some distance to attend. The “European Culture Capital” (ECC) mega event was created with the main objectives of bringing close together the people of the EU member states through cultural expression, and to give the EU and its cities an attractive image.Nowadays is a powerful tool to attract cultural tourists, promote urban and economic renewal and development in the cities.In this paper we will analyse the importance of “ECC” event to cultural tourism development,cultural publics enlargement, city’s equipments renewal, residents pride generation and “local” creative industries enhancement. Through “Porto 2001” event and its realizations, a critical discussion will be developed. Several short and long run will be identified, as well as implications in terms of city’s image. In this case-study, we will also verify the aims’ heterogeneity that’s present in this events development, which not permeates an exclusive “tourism analysis”info:eu-repo/semantics/publishedVersio

Studies on Mineral Supplementation in the Swamp Buffalo

Two experiments were conducted to study (a) the effect of mineral supplements on weight gain and on blood plasma calcium, inorganic phosphorus, magnesium, iron and copper in male and female swamp buffalo calves up to 10 months of age and (b) the effects of mineral and energy supplementation on the utilization of Guinea grass by swamp buffaloes. In the first experiment, 20 swamp buffalo calves (10 males, 10 females) were distributed into mineral supplemented and unsupplemented groups and rotationaly grazed through several paddocks and pasture species. Pastures comprised of Guinea (Panicum maximum), Signal (Brachiaria decumbens), Setaria (Setariaancep) and Star (Cynodon plectostachyus). Mineral supplementation with Phos-Rich, Rockies (Tithebarn, Ltd., England) had no significant effect on average daily gain from birth to weaning (6 months of age) and from birth to 10 months of age. However, mineral supplements had a significant (P<O.01) effect on average daily gain from weaning to 10 months of age. This experiment also demonstrated that there was a tendency for plasma inorganic phosphorus levels to be higher in supplemented animals as compared to unsupplemented animals. The concentration of plasma calcium had a tendency to be lower in the supplemented calves. Plasma inorganic phosphorus was negatively correlated (P<O.01) with age in both males and females. Plasma calcium levels in supplemented calves were positively correlated (P<O.O1) with age at 6 to 10 months of age but not significant at 2 to 6 months of age. In unsupplemented calves there were positive correlations (P<O.OI) with age (2 to 6 months) which were however not significant at 6 to 10 months of age. Average daily gain from birth to weaning (6 months of age) ranged from O.468-0.615 kg. Further, average daily gain from weaning to 10 months of age ranged from 0.527-0.537 kg for supplemented calves and 0.350-0.370 kg for unsupplemented calves. Plasma inorganic phospharus levels ranged from 8.26-9.19 mg per 100 ml (2 months), 4.68- 7.90 mg per 100 ml (6 months) and 3.84-4.43 mg per 100 ml at 10 months of age. Plasma calcium levels ranged from 5.04-6.69 mg per 100 ml (2 months), 7.21-8.29 mg per 100 ml (6 months ) and 10.02 to 11.08 mg per 100 ml at 10 months of age. Plasma magnesium levels of Swamp buffalo calves ranged from 1.03-3.85 mg per 100 ml while plasma iron and copper levels ranged from 1.33-1.76 mg per ml and from 0.43-1.19)mg per ml respectively

A Stochastic Geometry Framework for LOS/NLOS Propagation in Dense Small Cell Networks

The need to carry out analytical studies of wireless systems often motivates the usage of simplified models which, despite their tractability, can easily lead to an overestimation of the achievable performance. In the case of dense small cells networks, the standard single slope path-loss model has been shown to provide interesting, but supposedly too optimistic, properties such as the invariance of the outage/coverage probability and of the spectral efficiency to the base station density. This paper seeks to explore the performance of dense small cells networks when a more accurate path-loss model is taken into account. We first propose a stochastic geometry based framework for small cell networks where the signal propagation accounts for both the Line-of-Sight (LOS) and Non-Line-Of-Sight (NLOS) components, such as the model provided by the 3GPP for evaluation of pico-cells in Heterogeneous Networks. We then study the performance of these networks and we show the dependency of some metrics such as the outage/coverage probability, the spectral efficiency and Area Spectral Efficiency (ASE) on the base station density and on the LOS likelihood of the propagation environment. Specifically, we show that, with LOS/NLOS propagation, dense networks still achieve large ASE gain but, at the same time, suffer from high outage probability.Comment: Typo corrected in eq. (3); Typo corrected in legend of Fig. 1-2; Typos corrected and definitions of some variables added in Section III.E; Final result unchanged; Paper accepted to IEEE ICC 201

Massive M2M Access with Reliability Guarantees in LTE Systems

Machine-to-Machine (M2M) communications are one of the major drivers of the cellular network evolution towards 5G systems. One of the key challenges is on how to provide reliability guarantees to each accessing device in a situation in which there is a massive number of almost-simultaneous arrivals from a large set of M2M devices. The existing solutions take a reactive approach in dealing with massive arrivals, such as non-selective barring when a massive arrival event occurs, which implies that the devices cannot get individual reliability guarantees. In this paper we propose a proactive approach, based on a standard operation of the cellular access. The access procedure is divided into two phases, an estimation phase and a serving phase. In the estimation phase the number of arrivals is estimated and this information is used to tune the amount of resources allocated in the serving phase. Our results show that the proactive approach is instrumental in delivering high access reliability to the M2M devices.Comment: Accepted for presentation in ICC 201

Code-Expanded Random Access for Machine-Type Communications

The random access methods used for support of machine-type communications (MTC) in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. Motivated by the random access method employed in LTE, we propose a novel approach that is able to sustain a wide random access load range, while preserving the physical layer unchanged and incurring minor changes in the medium access control layer. The proposed scheme increases the amount of available contention resources, without resorting to the increase of system resources, such as contention sub-frames and preambles. This increase is accomplished by expanding the contention space to the code domain, through the creation of random access codewords. Specifically, in the proposed scheme, users perform random access by transmitting one or none of the available LTE orthogonal preambles in multiple random access sub-frames, thus creating access codewords that are used for contention. In this way, for the same number of random access sub-frames and orthogonal preambles, the amount of available contention resources is drastically increased, enabling the support of an increased number of MTC users. We present the framework and analysis of the proposed code-expanded random access method and show that our approach supports load regions that are beyond the reach of current systems.Comment: 6 Pages, 7 figures, This paper has been submitted to GC'12 Workshop: Second International Workshop on Machine-to-Machine Communications 'Key' to the Future Internet of Thing