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We have previously presented Intent, a medium access control scheme for WLANs based on cooperative, distributed, non-binding frame scheduling. The main idea behind Intent is intention sharing - a mechanism that allows a node to be aware of transmissions previously scheduled by its neighbors. We now extend this scheme to networks with hidden nodes. We give a formulation of the scheduling problem an
When implementing a language by means of attribute grammars, it is often useful to study example programs and their attributed trees, to understand the compiler structure, or for debugging. DrAST is a tool that allows interactive inspection of attributed trees. It is interfaced to the JastAdd metacompiler, and supports all JastAdd attribution mechanisms, such as demand evaluation, reference attrib
We present a general purpose algorithm for finding low-weight codewords as well as for decoding a received codeword in any quasi-cyclic code whose length and dimension is a multiple of a power of 2. In this paper, we apply the algorithm on a McEliece variant recently proposed by Misoczki et al. (MDPC-McEliece: New McEliece variants from moderate density parity-check codes, 2013). In their paper, t
Deciding the optimal project scope that fulfills the needs of the most important stakeholders is challenging due to a plethora of aspects that may impact decisions. Large companies that operate in rapidly changing environments experience frequently changing customer needs which force decision makers to continuously adjust the scope of their projects. Change intensity is further fueled by fierce ma
A wide band fractional-N digital PLL which uses a high resolution 2-dimension gated-Vernier time-to-digital converter (TDC) with 5.2 ps resolution is presented. The quantization noise shaping of the TDC greatly improves the in-band phase noise. While, in the same time, the 2-dimension structure makes the digital PLL (DPLL) be able to process large phase errors almost without the influence of laten
In this work we implement features for IEEE 802.11ac in the NS-3 simulator, in particular wider channels and bit-error calculations for higher modulation coding schemes. We also implement four wireless LAN deployment scenarios from the 802.11ax working group scenario document, and evaluate their performance under different operating conditions. Our simulation results demonstrate that many nodes in
Block diagram languages are often used for physical modeling and automation, where end users are domain engineers that instantiate block types and wire them together. Abstraction mechanisms in these languages allow specialists to build advanced reusable domain-specific libraries. However, this brings a tension between supporting reusability and making the language simple to comprehend for domain e
Ensuring that communication is secure, including the ability to encrypt sensitive traffic, has always been a fundamental pillar of the telecom industry. Users expect their right to privacy to be respected, and operators expect to be able to protect themselves and their customers from various kinds of attacks. But the world is changing. Encryption technologies are advancing, regulations are changin
We consider optimal precoder design for multi-user multiple-input multiple-output (MIMO) broadcasting channels in single-carrier (SC) systems. Instead of linear detection, we assume that advanced non-linear channel shortening (CS) detectors are utilized at the receivers. Such a scenario is challenging for precoder design as the uplink-downlink duality is inapplicable. The target of our linear prec
This dissertation presents the design and implementation of a new block diagram programming language, Bloqqi, for building control systems with focus on variability. The language has been developed in collaboration with industry with the goal of reducing engineering time and improving reuse of functionality.When building a control system for a plant, there are typically different variants of the s
In multipath routing, maximization of the cardinality K of the disjoint-path set for a given source and destination assuming an upper bound on the differential delay D is one of the key factors enabling its practical applications. In the paper we study such an optimization problem for multipath routing involving maximization of K under the D constraint as the primary objective, and then minimizati
Optimization of channel utilization in wireless networks is typically based on transmission parallelization under signal-to-interference and noise constraint assuming minimum frame-length scheduling. In application scenarios like sensor networks this approach may not be suitable since it does not explicitly consider end-to-end packet delay nor energy consumption. In the paper we propose a mixed-in
Changes in soil moisture are likely to contribute to future changes in latent heat flux and various characteristics of daily precipitation. Such contributions during the second half of the twenty-first century are assessed using the simulations from the GLACE-CMIP5 experiment, applying a linear regression analysis to determine the magnitude of these contributions. As characteristics of daily preci
Change Impact Analysis (CIA) during software evolution of safety-critical systems is a labor-intensive task. Several authors have proposed tool support for CIA, but very few tools were evaluated in industry. We present a case study on ImpRec, a recommendation System for Software Engineering (RSSE), tailored for CIA at a process automation company. ImpRec builds on assisted tracing, using informati
Quantitative data comes with enormous possibilities for presenting key characteristics of the data in a very compressed form. Basic descriptive statistics, like mean and standard deviation, comprise thousands or millions of data points into single numbers. In contrast, qualitative data, with its focus on descriptions, words, and phrases does not come with such powerful tools, leading to wordy desc
Finding new therapies for Parkinson's disease (PD) is a slow process. We assembled an international committee of experts to examine drugs potentially suitable for repurposing to modify PD progression. This committee evaluated multiple drugs currently used, or being developed, in other therapeutic areas, as well as considering several natural, non-pharmaceutical compounds. The committee prioritized
Although surface integral equations (SIEs) have been extensively used in solving electromagnetic problems of penetrable objects, there are still open issues relating to their application to the Theory of Characteristic Modes. This work demonstrates that when an SIE is used to solve for the characteristic modes (CMs) of a dielectric or magnetic object, the resulting eigenvalues are unrelated to the
The proper alignment of requirements engineering and testing (RET) can be key to software's success. Three practices can provide effective RET alignment: using test cases as requirements, harvesting trace links, and reducing distances between requirements engineers and testers. The Web extra https://youtu.be/M65ZKxfxqME is an audio podcast of author Elizabeth Bjarnason reading the the Requirements
This issue's letter discusses the proper use of sampling in software engineering research surveys.
