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A semantic editor, providing services like completion and code browsing, can help users to quickly develop high-quality source code. However, a lot of languages still lack semantic editor support due to the difficulty and costs of development. Tool generation and reuse can greatly alleviate this development task. Specifically, tool generation from a formal specification, such as reference attribut

In this work, we study YouTube traffic characteristics in a medium-sized Swedish residential municipal network that has 2600 mainly FTTH broadband-connected households. YouTube traffic analyses were carried out in the perspective of video clip category and duration, in order to understand their impact on the potential local network caching gains. To the best of our knowledge, this is the first tim

The problem of correctly recovering assembly instructions from a binary has received much attention and both malware and license validation code often relies on various anti-disassembly techniques in order to complicate analysis. One well-known anti-disassembly technique is to use overlapping code such that the disassembler starts decoding from an incorrect byte, but still recovers valid code. The

Evaluating SAR for multi-antennas is difficult and impractical due to the arbitrary power allocation and phase of the electric fields from different antennas causing the total field to change randomly. In this context, a simplified approach was recently proposed for assessing SAR when more than one antenna is transmitting simultaneously. The metric of time averaged simultaneous peak SAR (TASPS) wa

For some time, directional antennas have been considered to solve connectivity and interference issues in wireless networks. Several scenarios have been presented and often the conclusions drawn are positive, showing increase in capacity. However, to date there has been no effort to assess a holistic picture of the benefit/cost tradeoff and previous work mainly concerns either link scheduling or a

Numerous geometric problems in computer vision in- volve the solution of systems of polynomial equations. This is true for problems with minimal information, but also for finding stationary points for overdetermined problems. The state-of-the-art is based on the use of numerical linear algebra on the large but sparse co- efficient matrix that represents the expanded original equation set. In this

Reference attribute grammars (RAGs) can be used to express semantics as super-imposed graphs on top of abstract syntax trees (ASTs). A RAG-based AST can be used as the in-memory model providing semantic information for software language tools such as compilers, refactoring tools, and meta- modeling tools. RAG performance is based on dynamic attribute evaluation with caching. Caching all attributes

Multiplexing efficiency has recently been proposed as a performance metric for characterizing the absolute efficiency of MIMO antennas in a reference channel. In this work, we generalize this metric to account for arbitrary propagation channels, so the impact of the channel can also be studied. Using the extended definition of multiplexing efficiency, the respective roles of effective antenna gain

Analog decoders are constructed based on interconnecting CMOS Gilbert vector multipliers using transistors operating in the sub-VT region. They are seen as an interesting alternative to digital implementations with a low transistor count and a potential for a very low power consumption. Analog implementation makes the circuit sensitive to mismatch, requiring careful transistor sizing. A simulation

In this paper we prove threshold saturation for spatially coupled turbo codes (SC-TCs) and braided convolutional codes (BCCs) over the binary erasure channel. We introduce a compact graph representation for the ensembles of SC-TC and BCC codes which simplifies their description and the analysis of the message passing decoding. We demonstrate that by few assumptions in the ensembles of these codes,

In the emerging Delay Tolerant Networks (DTNs) content dissemination platform, mobile nodes opportunistically exchange content as they meet, with the intent of sharing content among nodes with common interests. During a meeting, nodes can exchange both content of direct interest to themselves as well as content that is of interest to a larger set of nodes that may be encountered in the future. The

In this paper, we give an overview of spatially coupled turbo codes (SC-TCs), the spatial coupling of parallel and serially concatenated convolutional codes, recently introduced by the authors. For presentation purposes, we focus on spatially coupled serially concatenated codes (SC-SCCs). We review the main principles of SC-TCs and discuss their exact density evolution (DE) analysis on the binary

Multipath routing gives traffic demands an opportunity to use multiple paths through a network. In a single-demand situation, its benefits are easy to see. In a multi-commodity case, when potentially all node-pairs (demands) generate traffic, they compete for the same network resources. In this work, we consider multipath routing in communication networks in a multi-commodity setting from a traffi

This paper presents a fully integrated downlink for low-cost remote antenna units in fiber-fed distributed multi-antenna systems. To reduce the cost of optical parts, an intermediate frequency(IF) signal is distributed over the fiber, and the circuit consists of an optical receiver, a single side-band frequency up-converting radio transmitter, and LO generation circuitry. The optical to electrical

[Context and motivation] This research preview presents ongoing work on a free software requirements modeling tool called reqT that is developed in an educational context. [Question/problem] The work aims to engage computer science students in Requirements Engineering (RE) through a tool that captures essential RE concepts in executable code. [Principal ideas] Requirements are modeled using an int

In this paper we study an optimization problem relevant for wireless networks. In such networks links are subject to capacity disruptions caused by changing weather/channel condition that force to adapt the modulation and coding schemes to the observed condition. To cope with this issue in network optimization, we need to consider a so called link availability set A and a routing strategy that can