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Communication is a key part of society that we make huge investments in. Each message has to both arrive quickly and use minimal network resources. Moreover, communications must sometimes also remain private, so encryption is used to prevent third parties from listening in. However, standard classical encryption protocols are proven not to be secure against quantum adversaries. With quantum communication we have a method that does provably attains perfect secrecy, even against adversaries with unlimited (quantum) computational power. It is, however, infeasible to have a direct quantum connection between all users of quantum communications. We thus look into the possibilities of a \emph{quantum network}, which is able to connect arbitrary users of the network as if they had direct quantum channel available. Once such a quantum network is built, we will need to route quantum messages effectively to their destination. In this work, we take the first step in studying network structures for quantum networks on a high level, and their accompanying routing algorithms. Current ongoing research into quantum communication with satellites and the possibility of a global network made the case of a quantum network of satellites relevant. We will consider a simplified model where each satellite can perform quantum communication with its immediate neighbours, and can create quantum virtual links that form shortcuts through the network. The first step towards a quantum network that we take is the structure of the network. Using virtual links as shortcuts we can reduce the maximum distance between nodes (the diameter) by an exponential factor. Let $|V|$ be the size of the set of all vertices in a graph, equal to the number of satellites. Then for the case of satellites we give a network structure with the following properties: \begin{itemize} \item The diameter of the graph is $4\log_2\left( \frac{|V|-2}{10} \right) +3 = O(\log |V|)$. This means that the distance between any two nod, Cyber Security Group, Intelligent Systems, Electrical Engineering, Mathematics and Computer Science

Communication is a key part of society that we make huge investments in. Each message has to both arrive quickly and use minimal network resources. Moreover, communications must sometimes also remain private, so encryption is used to prevent third parties from listening in. However, standard classical encryption protocols are proven not to be secure against quantum adversaries. With quantum communication we have a method that does provably attains perfect secrecy, even against adversaries with unlimited (quantum) computational power. It is, however, infeasible to have a direct quantum connection between all users of quantum communications. We thus look into the possibilities of a \emph{quantum network}, which is able to connect arbitrary users of the network as if they had direct quantum channel available. Once such a quantum network is built, we will need to route quantum messages effectively to their destination. In this work, we take the first step in studying network structures for quantum networks on a high level, and their accompanying routing algorithms. Current ongoing research into quantum communication with satellites and the possibility of a global network made the case of a quantum network of satellites relevant. We will consider a simplified model where each satellite can perform quantum communication with its immediate neighbours, and can create quantum virtual links that form shortcuts through the network. The first step towards a quantum network that we take is the structure of the network. Using virtual links as shortcuts we can reduce the maximum distance between nodes (the diameter) by an exponential factor. Let $|V|$ be the size of the set of all vertices in a graph, equal to the number of satellites. Then for the case of satellites we give a network structure with the following properties: \begin{itemize} \item The diameter of the graph is $4\log_2\left( \frac{|V|-2}{10} \right) +3 = O(\log |V|)$. This means that the distance between any two nod, Cyber Security Group, Intelligent Systems, Electrical Engineering, Mathematics and Computer Science

DWARV is a C-to-VHDL compiler which can compile arbitrary C programs for a heterogeneous platform with minimal effort. Depending on the application this will imply faster execution. We give an overview of C-to-VHDL compilers. One important aspect of all software is its reliability, and we aim to assess DWARV’s reliability and the adequacy of its test suite. Based on the identified shortcomings of the test suite, we implement the test result framework Dummy. We explore some of the additional possibilities created by the usage of Dummy, and provide a plan to improve DWARV’s test suite. We conclude with an analysis of the results that show the advantages of the implemented test framework and proposed test plan., Microelectronics & Computer Engineering, Electrical Engineering, Mathematics and Computer Science

DWARV is a C-to-VHDL compiler which can compile arbitrary C programs for a heterogeneous platform with minimal effort. Depending on the application this will imply faster execution. We give an overview of C-to-VHDL compilers. One important aspect of all software is its reliability, and we aim to assess DWARV’s reliability and the adequacy of its test suite. Based on the identified shortcomings of the test suite, we implement the test result framework Dummy. We explore some of the additional possibilities created by the usage of Dummy, and provide a plan to improve DWARV’s test suite. We conclude with an analysis of the results that show the advantages of the implemented test framework and proposed test plan., Microelectronics & Computer Engineering, Electrical Engineering, Mathematics and Computer Science

According to the endocrine model of hereditary dizygotic twinning, high FSH is responsible for multiple ovulation and pregnancy. Our study explored the underlying neuroendocrine causes. In a prospective clinical study, we compared the third day of menses parameters of episodic secretion of LH and FSH, the pituitary response to LHRH, plasma estradiol, and dimeric inhibin A and B in 16 regularly menstruating and 9 postmenopausal mothers of dizygotic twins with a family history of twinning and 14 premenopausal and 9 postmenopausal controls. Seven of 16 premenopausal mothers of twins had abnormally high FSH levels of more than 10 IU/L compared with 1/14 in controls (P = 0.024). In the premenopausal mothers of twins, mean FSH concentrations (P = 0.025) and FSH pulse frequency (P = 0.003) were significantly elevated, whereas FSH pulse amplitude and FSH response to LHRH were unaltered. For LH, neither the secretory parameters nor the response to LHRH was different. There were no differences between estradiol and inhibin A and B levels. Postmenopausal mothers of twin and controls did not differ with respect to the secretory pattern of LH and FSH. We conclude that under equal ovarian feedback conditions, premenopausal mothers of a dizygotic twin have hyper stimulation by endogenous FSH caused by neuroendocrine, hypothalamic, or pituitary mechanisms. This is the result of altered responsiveness to ovarian feedback and/or pituitary or suprapituitary, non-LHRH-like mechanisms that stimulate pulsatile FSH.

According to the endocrine model of hereditary dizygotic twinning, high FSH is responsible for multiple ovulation and pregnancy. Our study explored the underlying neuroendocrine causes. In a prospective clinical study, we compared the third day of menses parameters of episodic secretion of LH and FSH, the pituitary response to LHRH, plasma estradiol, and dimeric inhibin A and B in 16 regularly menstruating and 9 postmenopausal mothers of dizygotic twins with a family history of twinning and 14 premenopausal and 9 postmenopausal controls. Seven of 16 premenopausal mothers of twins had abnormally high FSH levels of more than 10 IU/L compared with 1/14 in controls (P = 0.024). In the premenopausal mothers of twins, mean FSH concentrations (P = 0.025) and FSH pulse frequency (P = 0.003) were significantly elevated, whereas FSH pulse amplitude and FSH response to LHRH were unaltered. For LH, neither the secretory parameters nor the response to LHRH was different. There were no differences between estradiol and inhibin A and B levels. Postmenopausal mothers of twin and controls did not differ with respect to the secretory pattern of LH and FSH. We conclude that under equal ovarian feedback conditions, premenopausal mothers of a dizygotic twin have hyper stimulation by endogenous FSH caused by neuroendocrine, hypothalamic, or pituitary mechanisms. This is the result of altered responsiveness to ovarian feedback and/or pituitary or suprapituitary, non-LHRH-like mechanisms that stimulate pulsatile FSH.

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Contains fulltext : 24779___.PDF (publisher's version ) (Open Access)

Item does not contain fulltext

Contains fulltext : 24779___.PDF (publisher's version ) (Open Access)

Contains fulltext : 24779___.PDF (publisher's version ) (Open Access)

Item does not contain fulltext