BDDT: Block-level Dynamic Dependence Analysis for Task-Based Parallelism

We present BDDT, a task-parallel runtime system that dynamically discovers and resolves dependencies among parallel tasks. BDDT allows the programmer to specify detailed task footprints on any memory address range, multidimensional array tile or dynamic region. BDDT uses a block-based dependence analysis with arbitrary granularity. The analysis is applicable to existing C programs without having to restructure object or array allocation, and provides flexibility in array layouts and tile dimensions.
We evaluate BDDT using a representative set of benchmarks, and we compare it to SMPSs (the equivalent runtime system in StarSs) and OpenMP. BDDT performs comparable to or better than SMPSs and is able to cope with task granularity as much as one order of magnitude finer than SMPSs. Compared to OpenMP, BDDT performs up to 3.9× better for benchmarks that benefit from dynamic dependence analysis. BDDT provides additional data annotations to bypass dependence analysis. Using these annotations, BDDT outperforms OpenMP also in benchmarks where dependence analysis does not discover additional parallelism, thanks to a more efficient implementation of the runtime system.

Hardware Comparison of the ISO/IEC 29192-2 Block Ciphers

As ubiquitous computing becomes a reality, sensitive information is increasingly processed and transmitted by smart cards, mobile devices and various types of embedded systems. This has led to the requirement of a new class of lightweight cryptographic algorithm to ensure security in these resource constrained environments. The International Organization for Standardization (ISO) has recently standardised two low-cost block ciphers for this purpose, Clefia and Present. In this paper we provide the first comprehensive hardware architecture comparison between these ciphers, as well as a comparison with the current National Institute of Standards and Technology (NIST) standard, the Advanced Encryption Standard.

Orthogonal space-time block coded rate-adaptive modulation with outdated feedbasck

Abstract-Channel state information (CSI) at the transmitter can be used to adapt transmission rate or antenna gains in multi-antenna systems. We propose a rate-adaptive M-QAM scheme equipped with orthogonal space-time block coding with simple outdated, finite-rate feedback over independent flat fading channels. We obtain closed-form expressions for the average BER and throughput for our scheme, and analyze the effects of possibly delayed feedback on the performance gains. We derive optimal switching thresholds maximizing the average throughput under average and outage BER constraints with outdated feedback. Our numerical results illustrate the immunity of our optimal thresholds to delayed feedback.

Rent: Prostitution and the Irish apartment block

In 1974, pursuing his interest in the infra-ordinary – ‘the banal, the quotidian, the obvious, the common, the ordinary, the back-ground noise, the habitual’ – Georges Perec wrote about an idea for a novel:

‘I imagine a Parisian apartment building whose façade has been removed … so that all the rooms in the front, from the ground floor up to the attics, are instantly and simultaneously visible’.

In Life A User’s Manual (1978) the consummation of this precis, patterns of existence are measured within architectural space with an archaeological sensibility that sifts through narrative and décor, structure and history, services and emotion, the personal and the system, ascribing commensurate value to each. Borrowing methods from Perec, to move somewhere between conjecture, analysis and other documentation and tracing relationships between form, structure, materiality, technology, organisation, tenure and narrative use, this paper interrogates the late twentieth-century speculative apartment block in Britain and Ireland arguing that its speculative and commodified purpose often allows a series of lives that are less than ordinary to inhabit its spaces.