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This work explores the n-well/p-substrate photodiode in a deep submicron CMOS process. A CMOS chip is designed featuring different structures of the photodiode. When characterized at a wavelength of 850nm DC responsivities between 0.12 and 0.16 A/W and 3-dB bandwidths of about 6 MHz with a roll-off of about 5.5dB/decade are measured. These investigations are very useful in designing the transimped
Internet of Things (IoT) devices can be equipped with multiple heterogeneous network interfaces. An overwhelmingly large amount of services may demand some or all of these interfaces’ available resources. Herein, we present a precise mathematical formulation of assigning services to interfaces with heterogeneous resources in one or more rounds. For reasonable instance sizes, the presented formulat
The 60 GHz band is very promising for high data rate (>1 Gb/s) wireless systems operating at short ranges. However, due to the short wavelengths in this frequency band, the shadowing effects cuased by human bodies and furniture are severe and need to be modeled properly. In this paper, we present an experimental, measurement-based characterization of the reflection and shadowing effects in the 60
Context: Software product lines (SPL) are used in industry to achieve more efficient software development. However, the testing side of SPL is underdeveloped. Objective: This study aims at surveying existing research on SPL testing in order to identify useful approaches and needs for future research. Method: A systematic mapping study is launched to find as much literature as possible, and the 64
Flexgrid technology has recently been presented as the most promising option for upgrading the currently operating fixed grid optical networks and extending their capacity to be able to deal with the massive traffic volumes forecast for the next decade. Although the current traffic is successfully supported on fixed grid networks, flexgrid technology brings features that are not offered by the fix
The post-failure convergence of shortest path routing (SPR) protocols used in IP networks can be too slow to meet the restrictive requirements (i.e. maximum allowable delay, jitter, etc.) of the multimedia services and therefore new protection/restoration mechanisms combined with IP routing are of interest. The article addresses the optimization of three potential rerouting mechanisms based on the
In this paper we establish a geometry-based stochastic ultra-wideband channel model for outdoor infostations scenarios. We statistically describe the location and strength of clusters of scatterers, as well as the shape and width of visibility and shadowing regions. We also separately model diffuse radiation (which cannot be explained by the scatterer components), and show that its fading statisti
Large software organizations with a product line development approach face many challenges regarding testing. Test managers need to make tradeoffs along three dimensions of repeated testing (abstraction level, time and product space) and consider a range of goals and constraints. In order to keep pace with the decreased development time for new products, which is enabled by the systematic reuse, s
In this article we prove NP-hardness of two well-known optimization problems related to the design of multicommodity flow networks with two different methods for providing network resiliency against failures: path diversity and flow restoration. Path diversity is a static mechanism that consists of using, for each demand, a number of paths and oversizing the flows assigned to these paths so that f
The presented study deals with a specific rerouting strategy for protecting traffic flows in communication networks called Flow Adjustment Routing. The strategy is designed to handle partial link failures. We present two variants of the strategy and analyze their pros and cons. We show that the initial strategy is not directly implementable to cope with severe link failures such as total link fail
This paper presents results for vehicle-to-vehicle channel characterization based on measurements conducted for the merging lane scenarios on a highway. We present power delay profiles as well as channel gains and analyze important propagation mechanisms to see the impact of line-of-sight (LOS) and the antenna radiation pattern on the total received power. It is found that the absence of LOS and s
In software product line engineering, testing for regression concerns not only versions, as in one-off product development, but also regression across variants. We propose a 3D process model, with the dimensions of level, version and variant, to help analyze, plan and manage software product line testing. We derive the model from empirical observations of regression testing practice and software p
It is well-known that the radio wave propagation mechanisms inside a tunnel are different from the typical outdoor and indoor situations. Since the tunnels represent a significant type of vehicular environments, understanding the channel characteristics for the in-tunnel scenario is crucial for intelligent transport systems design. A widely used tool for simulating channel characteristics for outd
Climate models provide the means of making projections of the future climate, under assumptions on alternative future land-use changes and greenhouse gas emissions. The basis for such climate projections is discussed in this chapter,´together with the presentation of overall climate scenario results of relevance for agriculture. The focus is on the period until 2050.
Effective requirements engineering (RE) can support efficient development of successful products. However, assessing and improving how RE supports its context, i.e. the development life cycle, is non-trivial since many different roles and factors are involved over a long period of time. Project retrospectives may support project teams in reflecting on how requirements are agreed upon and communica
An increasing number of studies have been focusing on the cognitive abilities and limitations of the designer during the design process, yet thus far only for the conceptual design phase. This paper deals with the embodiment design and detail design phases. We focus on the problem-solving process - strategies and basic steps - around the synthesis activity. Six experiments have been carried out, a
Background: The popularity of the open source software development in the last decade, has brought about an increased interest from the industry on how to use open source components, participate in the open source community, build business models around this type of software development, and learn more about open source development methodologies. Aim: The aim of this study is to review research ca
We present a method for solving the previously unstudied problem of localizing a set of receivers and directions from transmitters placed far from the receivers, measuring unsynchronized time of arrival data. The same problem is present in node localization of microphone and antenna arrays. The solution algorithm using 5 receivers and 9 transmitters is extended to the overdetermined case in a stra
