REAL-TIME ADAPTIVE PULSE COMPRESSION ON RECONFIGURABLE, SYSTEM-ON-CHIP (SOC) PLATFORMS

New radar applications need to perform complex algorithms and process a large quantity of data to generate useful information for the users. This situation has motivated the search for better processing solutions that include low-power high-performance processors, efficient algorithms, and high-speed interfaces. In this work, hardware implementation of adaptive pulse compression algorithms for real-time transceiver optimization is presented, and is based on a System-on-Chip architecture for reconfigurable hardware devices. This study also evaluates the performance of dedicated coprocessors as hardware accelerator units to speed up and improve the computation of computing-intensive tasks such matrix multiplication and matrix inversion, which are essential units to solve the covariance matrix. The tradeoffs between latency and hardware utilization are also presented. Moreover, the system architecture takes advantage of the embedded processor, which is interconnected with the logic resources through high-performance buses, to perform floating-point operations, control the processing blocks, and communicate with an external PC through a customized software interface. The overall system functionality is demonstrated and tested for real-time operations using a Ku-band testbed together with a low-cost channel emulator for different types of waveforms

Mathematical modelling and brain dynamical networks

In this thesis, we study the dynamics of the Hindmarsh-Rose (HR) model which studies the spike-bursting behaviour of the membrane potential of a single neuron. We study the stability of the HR system and compute its Lyapunov exponents (LEs). We consider coupled general sections of the HR system to create an undirected brain dynamical network (BDN) of Nn neurons. Then, we study the concepts of upper bound of mutual information rate (MIR) and synchronisation measure and their dependence on the values of electrical and chemical couplings. We analyse the dynamics of neurons in various regions of parameter space plots for two elementary examples of 3 neurons with two different types of electrical and chemical couplings. We plot the upper bound Ic and the order parameter rho (the measure of synchronisation) and the two largest Lyapunov exponents LE1 and LE2 versus the chemical coupling gn and electrical coupling gl. We show that, even for small number of neurons, the dynamics of the system depends on the number of neurons and the type of coupling strength between them. Finally, we evolve a network of Hindmarsh-Rose neurons by increasing the entropy of the system. In particular, we choose the Kolmogorov-Sinai entropy: HKS (Pesin identity) as the evolution rule. First, we compute the HKS for a network of 4 HR neurons connected simultaneously by two undirected electrical and two undirected chemical links. We get different entropies with the use of different values for both the chemical and electrical couplings. If the entropy of the system is positive, the dynamics of the system is chaotic and if it is close to zero, the trajectory of the system converges to one of the fixed points and loses energy. Then, we evolve a network of 6 clusters of 10 neurons each. Neurons in each cluster are connected only by electrical links and their connections form small-world networks. The six clusters connect to each other only by chemical links. We compare between the combined effect of chemical and electrical couplings with the two concepts, the information flow capacity Ic and HKS in evolving the BDNs and show results that the brain networks might evolve based on the principle of the maximisation of their entropies

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Engineering planetary lasers for interstellar communication

Transmitting large amounts of data efficiently among neighboring stars will vitally support any eventual contact with extrasolar intelligence, whether alien or human. Laser carriers are particularly suitable for high-quality, targeted links. Space laser transmitter systems designed by this work, based on both demonstrated and imminent advanced space technology, could achieve reliable data transfer rates as high as 1 kb/s to matched receivers as far away as 25 pc, a distance including over 700 approximately solar-type stars. The centerpiece of this demonstration study is a fleet of automated spacecraft incorporating adaptive neural-net optical processing active structures, nuclear electric power plants, annular momentum control devices, and ion propulsion. Together the craft sustain, condition, modulate, and direct to stellar targets an infrared laser beam extracted from the natural mesospheric, solar-pumped, stimulated CO2 emission recently discovered at Venus. For a culture already supported by mature interplanetary industry, the cost of building planetary or high-power space laser systems for interstellar communication would be marginal, making such projects relevant for the next human century. Links using high-power lasers might support data transfer rates as high as optical frequencies could ever allow. A nanotechnological society such as we might become would inevitably use 10 to the 20th power b/yr transmission to promote its own evolutionary expansion out of the galaxy

Proceedings of the 3rd International Workshop on Optimal Networks Topologies IWONT 2010

Peer Reviewe

Modelling sustainable ecotourism development on the Coromandel Peninsula in Aotearoa / New Zealand; a holistic systems approach based on the idea of chaos and complexity in a human-activity system

This thesis studies ecotourism in the context of sustainable tourism development. The research is based on the premise that ecotourism and sustainable development can be expressed as operational theoretical concepts and as fields of empirical inquiry. Positioned in the realm of applied qualitative research in the social sciences, the study’s leitmotiv is that sustainable ecotourism development can be represented from an integrative perspective by designing a conceptual system model. The field work consists of an empirical inquiry placed in the Coromandel Peninsula in New Zealand/Aotearoa. By employing a regional case study to test the hypotheses of the thesis, the research attains an insight in the operationalisation of ecotourism and sustainable ecotourism development. It further produces new knowledge regarding the theorisation and conceptualisation of ecotourism and sustainable tourism development. Two main goals drive the study. The first is the exploration of the ontological, epistemological and ideological matrix of a holistic and systemic research perspective. The second goal is the examination of the methodological and practical utility of conceptual system modelling as a research approach. The adopted strategy allows for causal, correlative and teleological interpretations of the spatio-temporal physical and mental phenomena encountered. With reference to critical realism the modelling process is recognised as an abstraction of ‘actual reality’ as opposed to ‘real reality’. Critical realism as an ontology accounts for the different ‘situated knowledges’ and worldviews that are present in the Coromandel Peninsula. The model itself reflects the researcher’s perception of an ‘empirical reality’, which is depicted at three resolution levels. Progressively coupling the different scales, the model design focuses on: (1) The configuration and behavioural patterns of the system as a whole; (2) the attributes of nested subsystems and their influences on each other as well as on the whole system; (3) the properties of individual system constituents, the processes and relationships linking these elements, and their effects on subsets of the system as well as on the system as a whole. Structural and process analyses, as well as an aetiological account of the system’s variables, do justice to the experienced complexity. At each resolution level the research outcome entails two simultaneously developed models. Both show the characteristics of open, complex and adaptive human-activity systems. While the first model reflects the status quo of sustainable ecotourism development in the Coromandel Peninsula, the second one represents an idealised archetype that can be used as a grid for further improvements. Neither model offers a fait accompli. Having identified ecotourism and sustainable tourism development as subjective and dynamic problem areas, answers exist within a continuum of differential interpretations, satisfying changing interests, needs and expectations. Solutions are thus of a suggestive and tentative nature. On a theoretical level, the study utilises ideas derived from ‘general system theory’ and the ‘chaoplexity paradigm’. Conceptually, it expands the philosophical notion of methodological holism into a pluralistic approach. Methodological triangulation is employed to compensate for the anticipated shortcomings of individual methods. In a pragmatic sense ecotourism and sustainable tourism development are viewed as anthropogenic phenomena that emerge at the interface between humans and the natural environment. Human agency is interpreted as the fulcrum of the system’s evolution, which operates in both the mental and physical dimension. Assuming that humans possess ‘free will’, and that rational and irrational as well as emotive and intuitive behaviour are inherent faculties of our nature, the system’s dynamics can not be sufficiently described via linear causalities. Non-linear relations, and a complex combination of multivariate and contingent causation, are interpreted predominantly as a result of human encounter and interaction. Answers to what should be ‘right’ and ‘wrong’ in ecotourism practice are based on the adoption of a pluralistic moral stance. This approach allows for competitive as well as cooperative elements as inherent human character traits that drive decision-making processes. Based on the findings, the thesis concludes with a flexible template of systemic indices that can evaluate the environmental performance and development of ecotourism. It is argued that utilising the suggested set of complex indicators in conjunction bears the potential to enhance sustainable ecotourism development. The template’s adaptability to specific situational contexts is viewed as a prerequisite to cater for changing demands and expectations of individuals, local communities and regions

Machine Medical Ethics

In medical settings, machines are in close proximity with human beings: with patients who are in vulnerable states of health, who have disabilities of various kinds, with the very young or very old, and with medical professionals. Machines in these contexts are undertaking important medical tasks that require emotional sensitivity, knowledge of medical codes, human dignity, and privacy. As machine technology advances, ethical concerns become more urgent: should medical machines be programmed to follow a code of medical ethics? What theory or theories should constrain medical machine conduct? What design features are required? Should machines share responsibility with humans for the ethical consequences of medical actions? How ought clinical relationships involving machines to be modeled? Is a capacity for empathy and emotion detection necessary? What about consciousness? The essays in this collection by researchers from both humanities and science describe various theoretical and experimental approaches to adding medical ethics to a machine, what design features are necessary in order to achieve this, philosophical and practical questions concerning justice, rights, decision-making and responsibility, and accurately modeling essential physician-machine-patient relationships. This collection is the first book to address these 21st-century concerns

New Foundation in the Sciences: Physics without sweeping infinities under the rug

It is widely known among the Frontiers of physics, that “sweeping under the rug” practice has been quite the norm rather than exception. In other words, the leading paradigms have strong tendency to be hailed as the only game in town. For example, renormalization group theory was hailed as cure in order to solve infinity problem in QED theory. For instance, a quote from Richard Feynman goes as follows: “What the three Nobel Prize winners did, in the words of Feynman, was to get rid of the infinities in the calculations. The infinities are still there, but now they can be skirted around . . . We have designed a method for sweeping them under the rug. [1] And Paul Dirac himself also wrote with similar tune: “Hence most physicists are very satisfied with the situation. They say: Quantum electrodynamics is a good theory, and we do not have to worry about it any more. I must say that I am very dissatisfied with the situation, because this so-called good theory does involve neglecting infinities which appear in its equations, neglecting them in an arbitrary way. This is just not sensible mathematics. Sensible mathematics involves neglecting a quantity when it turns out to be small—not neglecting it just because it is infinitely great and you do not want it!”[2] Similarly, dark matter and dark energy were elevated as plausible way to solve the crisis in prevalent Big Bang cosmology. That is why we choose a theme here: New Foundations in the Sciences, in order to emphasize the necessity to introduce a new set of approaches in the Sciences, be it Physics, Cosmology, Consciousness etc