Polar Code decoder exploration framework

The increasing demand for fast wireless communications requires sophisticated baseband signal processing. One of the computational intense tasks here is advanced Forward Error Correction (FEC), especially the decoding. Finding efficient hardware implementations for sophisticated FEC decoding algorithms that fulfill throughput demands under strict implementation constraints is an active research topic due to increasing throughput, low latency, and high energy efficiency requirements.This paper focuses on the interesting class of Polar Codes that are currently a hot topic. We present a modular framework to automatically generate and evaluate a wide range of Polar Code decoders, with emphasis on design space exploration for efficient hardware architectures. To demonstrate the efficiency of our framework a very high throughput Soft Cancellation (SCAN) Polar Code decoder is shown that was automatically generated. This decoder is, to the best of our knowledge, the fastest SCAN Polar Code decoder published so far.</p

Citizens observatories for effective Earth observations: the WeSenseIt approach

The WeSenseIt project defines citizen observatories as “A method, an environment and an infrastructure supporting an information ecosystem for communities and citizens, as well as emergency operators and policymakers, for discussion, monitoring and intervention on situations, places and events” . A collaborative approach has been taken to develop solutions that involve an exchange of information and expertise from all participants and where the focus is on arriving at practical solutions with a clear vision and direction. This has created a shared ownership scheme, and shifts power to the process itself rather than remaining within authorities, developers or decision-makers. The project’s emphasis is on delivering highly innovative technologies to support citizens, communities and authorities in developing a real-time situation awareness while ensuring all stakeholders play their part. Implementation has been through a combination of crowdsourcing, custom applications and dedicated web portals designed to foster collaboration, and which has created a shared knowledge base that facilitates decision-making processes and engages with communities. Data is captured via innovative sensors that are used directly by citizens, crowdsourcing from social networks (or by collective intelligence)

Transition Densities and Traces for Invariant Feller Processes on Compact Symmetric Spaces

We find necessary and sufficient conditions for a finite K–bi–invariant measure on a compact Gelfand pair (G, K) to have a square–integrable density. For convolution semigroups, this is equivalent to having a continuous density in positive time. When (G, K) is a compact Riemannian symmetric pair, we study the induced transition density for G–invariant Feller processes on the symmetric space X = G/K. These are obtained as projections of K–bi–invariant L´evy processes on G, whose laws form a convolution semigroup. We obtain a Fourier series expansion for the density, in terms of spherical functions, where the spectrum is described by Gangolli’s L´evy–Khintchine formula. The density of returns to any given point on X is given by the trace of the transition semigroup, and for subordinated Brownian motion, we can calculate the short time asymptotics of this quantity using recent work of Ba˜nuelos and Baudoin. In the case of the sphere, there is an interesting connection with the Funk–Hecke theorem

ECSA's Characteristics of Citizen Science: Explanation Notes

This explanation document provides an interpretation of and explanation for the characteristics document, which was kept short to make it useful to different stakeholders. In this document, the characteristics document is represented, with the original text in blue and an explanation in black

Knowledge for Change: A Decade of Citizen Science (2020–2030) in Support of the SDGs

In October 2020, the Museum für Naturkunde Berlin (MfN) with many partners, supported by the European Commission and the Federal Ministry of Education and Research (BMBF), held an international, hybrid conference in order to showcase, evaluate, and discuss the contribution of citizen science to frame and achieve the SDGs. The conference Knowledge for Change: A Decade of Citizen Science (2020-2030) in Support of the SDGs took place as an official event of Germany’s 2020 EU Council presidency. The SDGs are a scientifically based framework for the whole world to address hunger and malnutrition, health, environment as well as culture and justice, decided by the UN. Citizen Science, the contribution of lay people to scientific activities, may support the achievement of the SDGs – by providing data and insights, but also by adapting and prioritising research questions. Aim The conference presented, evaluated and discussed the exciting contributions that Citizen Science makes in framing and achieving sustainable development, specifically the UN SDGs. The conference brought together expertise from policy makers, institutional and citizen scientists, economists, NGOs and civil society to implement mechanisms and processes for the transition towards a more sustainable future. The Declaration A Declaration including policy recommendations resulted from the conference: "Our world – our goals: citizen science for the Sustainable Development Goals". The Declaration acts as a voluntary commitment by all partners to define the roles, competences and concrete potentials of Citizen Science to advance the SDGs. It was formulated in an open and participatory process. The Declaration groups the various important contributions of citizen science to the SDGs in three central recommendations: 1) Harness the benefits of citizen science for the SDGs, 2) strengthen citizen science and its connections with other communities, and 3) strengthen future citizen science systems

Cryptococcal Neuroradiological Lesions Correlate with Severity during Cryptococcal Meningoencephalitis in HIV-Positive Patients in the HAART Era

Cryptococcal meningoencephalitis has an overall global mortality rate of 20% in AIDS patients despite antifungals. There is a need for additional means of precise assessment of disease severity. We thus studied the radiological brain images available from 62 HIV-positive patients with cryptococcocal meningoencephalitis to analyse the brain lesions associated with cryptococcosis in relationship with disease severity, and the respective diagnostic contribution of magnetic resonance (MR) versus computed tomography (CT)

Contours of Citizen Science: A Vignette Study

Citizen science has expanded rapidly over the past decades. Yet, defining citizen science and its boundaries remained a challenge, and this is reflected in the literature - for example in the proliferation of typologies and definitions. There is a need for identifying areas of agreement and disagreement within the citizen science practitioners community on what should be considered as citizen science activity. This paper describes the development and results of a survey that examined this issue, through the use of vignettes - short case descriptions that describe an activity, while asking the respondents to rate the activity on a scale from ‘not citizen science’ (0%) to ‘citizen science’ (100%). The survey included 50 vignettes, of which 5 were developed as clear cases of not-citizen science activities, 5 as widely accepted citizen science activities, and the others addressing 10 factors and 61 sub-factors that can lead to controversy about an activity. The survey has attracted 333 respondents, who provided over 5,100 ratings. The analysis demonstrates the plurality of understanding of what citizen science is and calls for an open understanding of what activities are included in the field

Design space exploration of high throughput finite field multipliers for channel coding on Xilinx FPGAs

Channel coding is a standard technique in all wireless communication systems. In addition to the typically employed methods like convolutional coding, turbo coding or low density parity check (LDPC) coding, algebraic codes are used in many cases. For example, outer BCH coding is applied in the DVB-S2 standard for satellite TV broadcasting. A key operation for BCH and the related Reed-Solomon codes are multiplications in finite fields (Galois Fields), where extension fields of prime fields are used. A lot of architectures for multiplications in finite fields have been published over the last decades. This paper examines four different multiplier architectures in detail that offer the potential for very high throughputs. We investigate the implementation performance of these multipliers on FPGA technology in the context of channel coding. We study the efficiency of the multipliers with respect to area, frequency and throughput, as well as configurability and scalability. The implementation data of the fully verified circuits are provided for a Xilinx Virtex-4 device after place and route