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Concepts of cognitive radio are yet in an early stage of development. They aim at improving the efficiency of spectrum utilization by exploiting locally and temporally vacant parts of the spectrum. When hierarchical spectrum access is considered, secondary users are authorized to use spectrum white spaces on a non-interfering basis, where minimal impact on the primary systems has to be ensured. GF

Two main topics are considered in this thesis: Machining with industrial robot manipulators and optimal motion control of robots and vehicles. The motivation for research on the first subject is the need for flexible and accurate production processes employing industrial robots as their main component. The challenge to overcome here is to achieve high-accuracy machining solutions, in spite of the

Force sensing provides robots the capability to accomplish tasks where physical interaction with the environment is required, such as assembly. Small position uncertainties can then be corrected for by sensing the contact forces. This thesis considers the problem of force-controlled assembly, including how tasks can be specified in a simple and intuitive way and how robust task execution under unc

As a post-LOSC legal development, the precautionary principle is nowhere enunciated in the Law of the Sea Convention. Nevertheless, in the thirty years since the LOSC's adoption, the significance of the precautionary principle for marine environmental protection in general and marine resource conservation in particular has been recognised. The language of precaution, the precautionary principle an

Abstract in UndeterminedUzbekistan, after gaining independence from the Soviet Union in 1991, had publicly declared that it would adhere to democratic governance principles in designing and implementing its public administration policies. As a newly-independent state with democracy claims, Uzbekistan had tried to establish new democratic institutions with an effort to capture international communi

Generalized frequency division multiplexing is a non-orthogonal, digital multicarrier transmission scheme with attractive features that address the requirements of emerging applications of wireless communications systems in areas like cognitive radio and machine-to-machine communication. In this paper, first a linear system description is obtained for the transmitter by ordering data in a time-fre

Context processing refers to the operation of processing different types of context data and/or information using different kinds of operators. These operators are applied according to some conditions or constraints given in context queries. Existing context aware systems process context data in a centralized fashion to answer context queries and generate context information. However, this method

The topological characteristics of an IEEE 802.16 mesh network including the tree’s depth and degree of its nodes affect the delay and throughput of the network. To reach the desired trade-off between delay and throughput, all potential trees should be explored to obtain a tree with the proper topology. Since the number of extractable tree topologies from a given network graph is enormous, we use

Background: Little is known about the causes of thyroid cancer, but insulin-like growth factor-I (IGF-I) might play an important role in its development due to its mitogenic and antiapoptotic properties. Methods: This study prospectively investigated the association between serum IGF-I concentrations and risk of differentiated thyroid carcinoma in a case-control study nested within the European Pr

We investigate a family of protograph based rate-compatible LDPC convolutional codes. The code family shows improved thresholds close to the Shannon limit compared to their uncoupled versions for the binary erasure channel as well as the AWGN channel. In fact, the gap to Shannon limit is almost uniform for all members of the code family ensuring good performance for all subsequent incremental redu

The thesis discusses closed-loop control of the hypnotic and the analgesic components of anesthesia. The objective of the work has been to develop a system which independently controls the intravenous infusion rates of the hypnotic drug propofol and analgesic drug remifentanil. The system is designed to track a reference hypnotic depth level, while maintaining adequate analgesia. This is complicat

This work studies osteoinduction and bone conduction in polyvinyl alcohol-tetraethylorthosilicate-alginate-calcium oxide (PTAC) biocomposite cryogels along with the synergistic effect of electrical stimulation. In vitro osteoinduction of C2C12 myoblast towards osteogenic lineage is demonstrated through alkaline phosphatase assay, scanning electron microscopy and energy dispersive X-ray spectroscop

Changes in vascular tone brought about by electrical field stimulation were studied in isolated guinea-pig and monkey pial arteries, using stimulus intensities similar to, or weaker than, those usually utilized by other investigators. In the guinea-pig, excitation of the smooth muscle cells was easily induced, even at low intensity stimulus parameters. This contraction faded upon repeated stimulat

The dissociation of DNA-cationic surfactant complexes with the addition of a negative amphiphile was studied by fluorescence microscopy (FM). The unfolding of DNA molecules previously compacted with cationic surfactant was shown to be dependent on the anionic surfactant chain length; lower amounts of a longer-chain surfactant were needed to release DNA into solution. However, we observed no depend

Mechanical properties and rate of ATP breakdown (JATP) have been determined in the chemically skinned guinea-pig taenia coli at 22 degrees C. The influence of varied [Ca2+], [Mg ATP] and muscle length were investigated. The shortening response after a step decrease in force (isotonic quick release) was highly curvilinear in the first 100-200 ms. This effect was shown to be a time-dependent respons

The phase formation, heat of hydration and dilatation in a blended cement consisting of 50 wt.% calcium aluminate cement, 25 wt.% Portland cement and 25 wt.% calcium sulfate were studied (w/c= 1). The calcium sulfate was beta-hemilrydrate, anhydrite and mixes of the two. Kinetic expressions describing the ettringite formation in the pastes with the pure calcium sulfates were found. Hydration react

A special gait-training programme, combining a psychological therapeutic approach with methods in physiotherapy and body awareness, was used to re-educate nine unilateral trans-femoral amputees. All were rehabilitated trauma or tumour amputees with an age of 16-60 years. They had worn prostheses for more than 18 months. The re-education aimed at integrating the prosthesis in normal movements and i

The transition model (i) of classical phonetics distinguished between inevitable transitions between momentary target configurations (called coarticulation by Menzerath and Lacerda in 1933) and assimilation extending over a larger domain than a transition, implying reorganization of the input. By the 1950s it was clear that coarticulation extended beyond target configurations and involved more tha

In the present work we determine the adsorption site of two polyatomic molecules, methoxy and ethoxy, on Cu(100). This is accomplished by comparing experimental intramolecular vibrational modes to the corresponding modes calculated by first principle methods. We explore the three different high symmetry adsorption sites on top, bridge and hollow using several different metal clusters to represent