Interference Alignment (IA) and Coordinated Multi-Point (CoMP) with IEEE802.11ac feedback compression: testbed results

We have implemented interference alignment (IA) and joint transmission coordinated multipoint (CoMP) on a wireless testbed using the feedback compression scheme of the new 802.11ac standard. The performance as a function of the frequency domain granularity is assessed. Realistic throughput gains are obtained by probing each spatial modulation stream with ten different coding and modulation schemes. The gain of IA and CoMP over TDMA MIMO is found to be 26% and 71%, respectively under stationary conditions. In our dense indoor office deployment, the frequency domain granularity of the feedback can be reduced down to every 8th subcarrier (2.5MHz), without sacrificing performance.Comment: To appear in ICASSP 201

Success in the Film Industry: What Elements Really Matter in Determining Box-Office Receipts

This paper attempted to answer the research question, “What determines a film’s success at the domestic box office?” The authors used an OLS regression model on an expanded data set of 497 films from the randomly selected years 2005, 2006, 2007, 2009, and 2011, taking the top 100 films from each year. Domestic box-office receipts served as the dependent variable, with MPAA ratings, critical reviews, source material, release date, and number of screens acting as independent variables in the final regression. Results showed that source material, critical reviews, number of screens, release date, and a PG rating were statistically significant and positively contributed to a film’s domestic revenue. The authors conclude therefore that the consistently significant variables of reviews, release date, source material, and certain genres contain the most explanatory power

Neurological consequences of traumatic brain injuries in sports.

Traumatic brain injury (TBI) is common in boxing and other contact sports. The long term irreversible and progressive aftermath of TBI in boxers depicted as punch drunk syndrome was described almost a century ago and is now widely referred as chronic traumatic encephalopathy (CTE). The short term sequelae of acute brain injury including subdural haematoma and catastrophic brain injury may lead to death, whereas mild TBI, or concussion, causes functional disturbance and axonal injury rather than gross structural brain damage. Following concussion, symptoms such as dizziness, nausea, reduced attention, amnesia and headache tend to develop acutely but usually resolve within a week or two. Severe concussion can also lead to loss of consciousness. Despite the transient nature of the clinical symptoms, functional neuroimaging, electrophysiological, neuropsychological and neurochemical assessments indicate that the disturbance of concussion takes over a month to return to baseline and neuropathological evaluation shows that concussion-induced axonopathy may persist for years. The developing brains in children and adolescents are more susceptible to concussion than adult brain. The mechanism by which acute TBI may lead to the neurodegenerative process of CTE associated with tau hyperphosphorylation and the development of neurofibrillary tangles (NFTs) remains speculative. Focal tau-positive NFTs and neurites in close proximity to focal axonal injury and foci of microhaemorrhage and the predilection of CTE-tau pathology for perivascular and subcortical regions suggest that acute TBI-related axonal injury, loss of microvascular integrity, breach of the blood brain barrier, resulting inflammatory cascade and microglia and astrocyte activation are likely to be the basis of the mechanistic link of TBI and CTE. This article provides an overview of the acute and long-term neurological consequences of TBI in sports. Clinical, neuropathological and the possible pathophysiological mechanisms are discussed. This article is part of a Special Issue entitled 'Traumatic Brain Injury'

Establishing a Regional AIS Application Specific Message Register

The goal of the Regional AIS Application Specific Message Register is to provide awareness of what applications exist, facilitate harmonization, and promote proper binary messaging for regional applications. To be hosted on the IALA website, establishing the Register will be a 3-step process: 1) Compile all existing AIS binaries into a Jcollection.K 2) Convert the JcollectionK into a Register. 3) Develop IALA guidance on best practices for creating and using AIS Binary Messages. Recommendations are provided in regard to: - Benefit of a web-based HTML user interface for input/output. - Use of XML to organize/format register applications in a consistent manner. - Having the collection/registration become a JloopK process. - Conforming to ISO standards to organize and manage the Register. - Benefit of a joint IMO-IALA register for both international and regional applications

Measured and modelled long-term effects of whole-tree harvest

This thesis examines the impact of whole-tree harvest (WTH) on soils and surface waters acid-base status in coniferous forests compared with conventional harvesting (CH). A combination of field observations (up to four decades) and dynamic modelling was used to describe the impact on soil calcium (Ca²⁺) pools and surface water acid neutralizing capacity (ANC). The studies were undertaken in northern and southern Sweden at sites belonging to the long-term wood fuel experiment (HELTRAD) and the ICP Integrated Monitoring (IM) programme. One of the most important findings was that WTH and CH caused large depletions (up to 60%) in soil exchangeable Ca²⁺ pools, circa 40 years after harvest. Despite these losses, tree growth and vitality has not yet been impaired. The results also implied that the fastest depletion rates occurred in CH-plots why soil Ca²⁺ pools between CH and WTH have become more similar with time. However, soil Ca²⁺ pools still remained significantly lower after WTH. Measured differences in soil solution showed that the impact of WTH on ANC was small (16 μEq l⁻¹) and temporary but site-specific. This difference was not large enough to counteract the natural recovery from acidification or lead to adverse ecological effects. The results indicate that WTH can have a large impact on soil exchangeable pools without causing surface water acidification in the absence of strong acid mobile anions. The rapidly declining soil Ca²⁺ pools may be of concern for sustainable forest management. However, trees will likely respond to lower Ca²⁺ availability by e.g. adjusting their uptake or develop biological feed-back mechanisms. The model predictions unanimously suggested that tree growth and net accumulation of nutrients in biomass caused large depletions in soil exchangeable Ca²⁺ pools and a decrease in stream ANC during the 19th and 20th centuries, exacerbated by acid deposition. Future predictions also suggested that these Ca²⁺ losses would continue accelerated by more intense harvesting practices. The impact on modelled stream ANC was smaller and depended on the concentrations of mobile anions. The empirical data pointed in the same direction as the MAGIC predictions, but the model exaggerated the impact. Until the discrepancy between measured and modelled impact have been resolved, interpretations changes related WTH using dynamic modelling or mass balance budget calculations should be done with caution

The Ten-Year Rule: Allocation of Emission Allowances in the EU Emission Trading System

In its guidance on National Allocation Plans (NAPs), the European Commission has discouraged Member States from adopting allocation methodologies that would provide incentives to firms affecting their compliance behavior. The purpose is to promote economic efficiency and to prevent strategic behavior that deviates from individual and collective cost-minimization. For example, some methodologies would reward one type of compliance investment over another. To discourage such actions, the EU Emission Trading System guidelines prohibit ex post redistribution of emission allowances within an allocation period based on behavior in that period. Similarly, the Commission has indicated that decisions about the initial distribution of allowances in the second phase (2008-2012) must depend on measures prior to 2005 so as not to give companies an incentive to adjust their behavior to receive a larger allowance allocation. However, two other aspects of the NAPs—the treatment of closures and new entrants—may also affect firm behavior. An undercurrent in these guidelines is the question of whether Member States should allow incumbent emitters to hold infinitely lived, once-and-for-all property rights to a share of the emission allowances in the future. This paper develops an approach for balancing efficiency considerations with perceived issues of fairness. We propose a ten-year rule to guide policy regarding closure of existing sources and the status of new sources and to guide the initial distribution of emission allowances in general. A ten-year rule would address issues of fairness and capture an important part of the potential gains that could be achieved through an efficient initial distribution of allowances.emission trading, allowance allocations, closures, new entrants, tradable permits, air pollution, cost-effectiveness, greenhouse gases, climate change, global warming, carbon dioxide