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We consider the problem of controlling the transmission rate in a communication network where each node adjusts its own transmission rate exclusively based on the physical medium occupation (the band occupancy of the aggregate complementary nodes). We show how to design a decentralized control for maximizing both band occupancy and fairness. If the network is fully connected, the problem admits a
This paper proposes a discrete-time hazard regression approach based on the relation between hazard rate models and excess over threshold models, which are frequently encountered in extreme value modelling. The proposed duration model employs a flexible link function and incorporates the grouped-duration analogue of the well-known Cox proportional hazards model and the proportional odds model as s
In this paper, we describe KOSHIK, an end-to-end framework to process the unstructured natural language content of multilingual documents. We used the Hadoop distributed computing infrastructure to build this framework as it enables KOSHIK to easily scale by adding inexpensive commodity hardware. We designed an annotation model that allows the processing algorithms to incrementally add layers of a
The massive amounts of text data made available through the Google Books digitization project have inspired a new field of big-data textual research. Named culturomics, this field has attracted the attention of a growing number of scholars over recent years. However, initial studies based on these data have been criticized for not referring to relevant work in linguistics and language technology.
The stability of a multi-controller system is analyzed using Lyapunov theory. Stability is guaranteed by a switching strategy determined by a combination of separate Lyapunov functions for the different controllers. The behavior on sliding surfaces is analyzed using non-smooth analysis according to Filippov. Two examples illustrate the theory.
Since the last decade, development efforts by academia and industry for automated driving functions have increased significantly. Also, the European research project AdaptIVe is looking into this topic. Due to the large operation spaces and various complex situations that are covered by these functions, efforts for evaluation increase also significantly. Within AdaptIVe, a comprehensive evaluation
This work analyzes the effects on support recovery for different choices of the hyper- or regularization parameter in LASSO-like sparse and group-sparse regression problems. The hyperparameter implicitly selects the model order of the solution, and is typically set using cross-validation (CV). This may be computationally prohibitive for large-scale problems, and also often overestimates the model
The present study uses the concept of technological efficacy derived from ecological psychology and design studies to offer an alternative way of analyzing how policy instruments affect change. Reasoning from this, the paper outlines a framework for analyzing policy instruments in terms of their affordances. We define affordances as the means through which an instrument exerts influence on its int
Background: Counseling by experienced midwives is offered to women with childbirth fear in most obstetric clinics in Sweden, but information about the content of such counseling is lacking. Aim: To study comprehensiveness, content and organization of the midwife-led counseling for childbirth fear in all obstetric clinics in Sweden. Methods: In this cross-sectional study, data were collected using
Objective: Interferon gamma release assays like Quantiferon Gold In-Tube (QFT) are used to identify individuals infected with Mycobacterium tuberculosis. A dichotomous cut-off (0.35 IU/ml) defines a positive QFT without considering test variability. Our objective was to evaluate the introduction of a borderline range under routine conditions. Methods: Result
This toolbox works similar to that of other major computer-aided control systems design (CACSD) toolboxes. Systems can be created in either a transfer function or a state space representation. These systems can then be combined into larger architectures, simulated in both time and frequency domain, and analyzed for stability/performance properties.
A strategy for control of substrate feed rate in fed-batch fermentations is presented. The main idea is to make pulses in the feed rate and to evaluate the response in the dissolved oxygen signal. This gives an indirect measurement of the substrate demand that is used for feedback control of the feed rate. Experimental data is used to develop a model of a fermentation process. The model is used to
A strain-independent feeding strategy for fed-batch cultures of Escherichia coli is presented. The key idea is to exploit a characteristic change in the cell metabolism at the onset of acetate formation. By superimposing short pulses in the glucose feed rate, on-line detection of acetate formation can be made using a standard dissolved oxygen sensor. A simple feedback algorithm is then us
