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The hypothesis of this thesis is that climate models should take structural vegetation changes that operate on interannual to centennial time scales into account in order to simulate climate change in a more realistic manner. To evaluate this hypothesis, a regional Earth System Model (ESM) has been developed, validated and applied over Europe. The model has enabled the identification of a number o
Separable Lyapunov functions play vital roles, for example, in stability analysis of large-scale systems. A Lyapunov function is called max-separable if it can be decomposed into a maximum of functions with one-dimensional arguments. Similarly, it is called sum-separable if it is a sum of such functions. In this paper it is shown that for a monotone system on a compact state space, asymptotic stab
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
In this paper, nonlinear model predictive control (NMPC) is applied to the start-up of a combined-cycle power plant. An object-oriented first-principle model library expressed in the high-level language Modelica has been written for the plant and used to set up the simulation and optimization models. The NMPC optimization problems are both encoded, using a high-level notation, and solved in the op
Autonomic computing was proposed as a promising solution to overcome the complexity of modern systems, which is causing management operations to become increasingly difficult for human beings. This work proposes the Adaptation Manager, a comprehensive framework to implement autonomic managers capable of pursuing some of the objectives of autonomic computing (i.e., self-optimization and self-healin
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
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
Vehicular networks bring new ways of viewing road traffic management and safety applications. For the first time, it will be possible for vehicles to exchange information and build fine-grained knowledge about the current situation, estimating risks and adapting their driving. Central to these applications is the need to exchange information in a highly dynamic environment, building a view of the
We consider a window decoding scheme for Braided Convolutional Codes (BCCs) based on the BCJR algorithm. We describe the principle of this decoding scheme and show that BCCs with window decoding exhibit excellent performance. The tradeoff between performance and decoding latency is examined and, to reduce decoding complexity, both uniform and nonuniform message passing schedules within the decodin
We derive an analytic solution to the problem of fixed-time trajectory generation with a quadratic cost function under velocity and acceleration constraints. This problem has a wide range of applications within motion planning. The advantage of the analytic solution compared to numerical optimization of the discretized problem is the unlimited resolution of the solution and the efficiency of the c
It is well known that fast correlation attacks can be very efficient if the feedback polynomial is of low weight. These feedback polynomials can be considered weak in the context of stream ciphers. This paper generalizes the class of weak feedback polynomials into polynomials were taps are located in several groups, possibly far apart. Low weight feedback polynomials are thus a special case of thi
Two gated ring oscillators (GROs) act as the delay lines in an improved Vernier time-to-digital converter (TDC), where the already small quantization noise of the standard Vernier TDC is further first-order shaped by the GRO operation. The TDC has been implemented in a 90nm CMOS process and consumes 3mA from 1.2V when operating at 25MHz. The native Vernier resolution of the TDC is 5.8ps, while the
Successful development of software systems involves efficient navigation among software artifacts. However, as artifacts continuously are produced and modified, engineers are typically plagued by challenging information landscapes. One state-of-practice approach to structure information is to establish trace links between artifacts, a practice that is also enforced by several development standards
