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The computation power we expect from the various smart devices we use keeps increasing. Not only do we want faster devices but also less power hungry and energy efficient devices, both for the environment and our personal convenience (remember that "mobile phone" attached to a power plug at all times?).One way of addressing this demand is to build custom processor architectures that focus on a spe

MapReduce has become the standard model for supporting big data analytics. In particular, MapReduce job optimization has been widely considered to be crucial in the implementations of big data analytics. However, there is still a lack of guidelines especially for practitioners to understand how the MapReduce jobs can be optimized. This paper aims to systematic identify and taxonomically classify t

Partially premixed combustion (PPC) is a low temperature, direct-injection combustion concept that has shown to give promising emission levels and efficiencies over a wide operating range. In this concept, high EGR ratios, high octane-number fuels and early injection timings are used to slow down the auto-ignition reactions and to enhance the fuel and are mixing before the start of combustion. A d

To reduce the congestion due to the future bandwidth- hungry applications in domains such as Health care, Internet of Things (IoT), etc., we study the benefit of introducing additional Data Centers (DCs) closer to the network edge for the optimal application placement. Our study shows that the edge layer DCs in a Mobile Edge Network (MEN) infrastructure is cost beneficial for the bandwidth-hungry

Requirements Engineering has attracted a great deal of attention from researchers and practitioners in recent years. This increasing interest requires academia to provide students with a solid foundation in the subject matter. In Requirements Engineering Education (REE), it is important to cover three fundamental topics: traditional analysis and modeling skills, interviewing skills for requirement

Deterministic builds, where the compile and build processes are reproducible, can be used to achieve increased trust in distributed binaries. As the trust can be distributed across a set of builders, where all provide their own signature of a byte-to-byte identical binary, all have to cooperate in order to introduce unwanted code in the binary. On the other hand, if an attacker manages to incorpor

This paper describes an extensive propagation channel measurement campaign in a warehouse environment for line-of-sight (LOS) and nonline-of-sight (NLOS) scenarios. The measurement setup employs a vector network analyzer operating in the 2-8-GHz frequency band combined with an 8×8 virtual multiple-input multiple-output (MIMO) antenna array. We develop a comprehensive statistical propagation channe

This contribution presents a novel model-based methodology for open-loop optimal control of batch high-pressure liquid chromatographic (HPLC) separation processes. The framework allows for simultaneous optimization of target component recovery yield and production rate with respect to a parameterization of the input elution trajectory and fractionating interval endpoints. The proposed methodology

We investigate antenna correlation of an M-antenna massive multiple-input multiple-output (MIMO) setup with the purpose of obtaining a low-rank representation of the instantaneous massive MIMO channel. Low-rank representation bases using short-term and long-term antenna correlation statistics are defined, and their performance is evaluated with data sets obtained from channel measurements in both

Coordinated Multi Point (CoMP) transmission and reception techniques are used in order to improve the performance of single or multiple cells in wireless systems. A system using CoMP techniques is capable of jointly optimizing its transmission and/or reception and, hence, achieving higher performance. In this work, performance evaluation of three CoMP techniques are performed based on simulations

The possibility of using radio over fiber (RoF) analog transmissions to characterize the wireless propagation channel of distributed antenna systems is investigated. In particular, the coherence time of kilometer-long, fiber-based networks is analyzed. Joint measurements of the phase noise of parallel links to the same site (intra-site) and to different sites (inter-site) in such a network are pre

This paper presents an approach to the synthesis of low-power fault-tolerant hard real-time applications mapped on distributed heterogeneous embedded systems. Our synthesis approach decides the mapping of tasks to processing elements, as well as the voltage and frequency levels for executing each task, such that transient faults are tolerated, the timing constraints of the application are satisfie

A fully integrated remote antenna unit (RAU) intended for fiber-fed distributed multiple-input multiple-output systems is presented. The circuit is designed for narrowband (60 MHz) time-division duplex systems, where an IF over fiber approach is chosen to facilitate the use of low-cost optical components and integrated photodetectors. A novel antenna switch control scheme is introduced, which enab

Massive MIMO is a promising technology for the coming 5G wireless systems. In this paper, a programmable baseband processor specifically designed for uplink symbol detection targeting massive MIMO is presented with a novel matrix inversion method proposed to obtain more precise and efficient computation. Including a microcode controlled channel preprocessing unit and a pipelined detection unit, th

This paper serves as an overview to the special session Circuits and Systems for 5G on IEEE International Conference on ASIC (ASICON) 2015. More specifically, we introduce two of enabling technologies for the coming 5G wireless era, namely massive multiple-input multiple-output (MIMO) technique and advanced coding techniques such as polar codes. Massive MIMO is a relatively new wireless communicat

The objective of this paper is to design a compressor for silicon debug that is suitable in an industrial Nexus environment. The compressor must operate in real-time and must be lossless. Important for the compressor is high compression ratio, low hardware cost and high throughput. We implemented the compression on an FPGA and we compared our implementation in terms of throughput and hardware cost

Changes in vehicle emission reduction technologies significantly affect traffic-related emissions in urban areas. In many densely populated areas the amount of traffic is increasing, keeping the emission level high or even increasing. To understand the health effects of traffic-related emissions, both primary (direct) particulate emission and secondary particle formation (from gaseous precursors i

A three bit second order delta sigma modulator for audio applications implemented in 130nm CMOS technology is presented. The modulator features two integrators, a flash quantizer and two current steering DACs. In order to minimize the effect of delays in the DACs, excessive loop delay (ELD) compensation is utilized. Using an oversampling ratio (OSR) of 80, the design consumes 2.8mW and achieves a

In this paper we present an audio synthesizer that creates audio signals, intended to be reproduced as sound by a loudspeaker. This paper details the design, implementation and verification of an analog, subtractive audio synthesizer. The synthesizer produces a variety of waveforms spanning approximately 3 octaves. The frequency is controlled by an external voltage and the harmonic content is regu

Further exploitation of the spatial domain, as in Massive MIMO (MaMi) systems, is imperative to meet future communication requirements [1]. Up-scaling of conventional 4×4 small-scale MIMO implementations to MaMi is prohibitive in-terms of flexibility, as well as area and power cost. This work discloses a 1.1mm2 128×8 MaMi baseband chip, achieving up to 12dB array and 2× spatial multiplexing gains.