Galactic cosmic rays are the high-energy particles that stream into our solar system from distant corners of our Galaxy. The Earth's atmosphere serves as an ideal detector for the high energy cosmic rays which interact with the air molecule nuclei causing propagation of extensive air showers. The primary cosmic ray particles interact with the molecules in the atmosphere and produce showers of secondary particles (mainly pions) at about 15 km altitude. These pions decay into muons which are the dominant particles of radiation (about 80%) at the surface of the Earth. In recent years, there are growing interests in the applications of the cosmic ray measurements such as space/earth weather monitoring, homeland security activities based on the cosmic ray muon tomography, radiation effects on health via air travel, etc. A simulation program (based on the Geant4 software package developed at CERN) has been developed at Georgia State University for studying cosmic ray showers in the atmosphere. The results of this simulation study will provide unprecedented knowledge of geo-position-dependent cosmic ray shower profiles and will significantly advance cosmic ray applications. Simulation results are critically important for determining the temperature coefficients in every pressure layer in the atmosphere in order to calculate the temperature variations using the cosmic ray data. Using a single particle shower simulation, the weighted particle altitude distributions on a global scale are calculated with geomagnetic field implementation. The results of the simulation can aid the computation of the effective temperature in stratosphere.

The complex interactions between the Sun and Earth are referred to as Space Weather. Key parameters include magnetic indices which quantitatively describe geomagnetic activity by determining a baseline that removes the background magnetic field and allows quantification of the remaining activity during geomagnetic events. However, most used indices have a low temporal resolution and rely on a sparse and frozen network of ground magnetic observatories. This thesis introduces a novel way of determining the baseline for future high temporal and spatial resolution magnetic indices. Firstly, the main phenomena and effects of Space Weather are outlined, followed by a review of currently used magnetic indices and their derivation. The computation of a novel baseline introduced in this work relies on basic statistical methods which are applied on magnetic data from a dense and flexible network of ground observatories for the period 1991-2016. The focus is on the investigation of geomagnetic quiet periods for which average annual activity at each observatory is determined. A global latitudinal normalisation function with dependency on solar activity for quiet periods is found. The analysis of the newly derived baseline shows that it provides the temporal, spatial and amplitudinal resolution needed to characterise geomagnetic disturbances adequately. The residual signal has the capability of being used as the basis for further quiet period studies. A first attempt of new indices based on the introduced derivation shows a good agreement with already existing high temporal and spatial resolution magnetic indices. Future indices derived with this baseline lay a favourable fundament for the application of articial intelligence methods.

Magnetoelectric (ME) effect, a cross-coupling effect between magnetic and electric orders, has stimulated lots of investigations due to the potential for applications as multifunctional devices. In this thesis, I have investigated and optimized the ME effect in Metglas/piezo-fibers ME composites with a multi-push pull configuration. Moreover, I have also proposed several devices based on such composites. In this thesis, several methods for ME composites optimization have been investigated. (i)  the ME coefficients can be enhanced greatly by using single crystal fibers with high piezoelectric properties; (ii) the influence of volume ratio between Metglas and piezo-fibers on ME coefficients has been studied both experimentally and theoretically. Modulating the volume ratio can increase the ME coefficient greatly; and (iii) the annealing process can change the properties of Metglas, which can enhance the ME response as well. Moreover, one differential structure for ME composites has been proposed, which can reject the external vibration noise by a factor of 10 to 20 dB. This differential structure may allow for practical applications of such sensors in real-world environments. Based on optimized ME composites, two types of AC magnetic sensor have been developed. The objective is to develop one alternative type of magnetic sensor with low noise, low cost and room-temperature operation; that makes the sensor competitive with the commercially available magnetic sensor, such as Fluxgate, GMR, SQUID, etc. Conventional passive sensors have been fully investigated, including the design of sensor working at specific frequency range, sensitivity, noise density characterization, etc. Furthermore, the extremely low frequency (< 10-3 Hz) magnetic sensor has undergone a redesign of the charge amplifier circuit. Additionally, the noise model has been established to simulate the noise density for this device which can predict the noise floor precisely. Based on theoretical noise analysis, the noise floor can be eliminated greatly. Moreover, another active magnetic senor based on nonlinear ME voltage coefficient is also developed. Such sensor is not required for external DC bias that can help the sensor for sensor arrays application. Inspired by the bio-behaviors in nature, the geomagnetic sensor is designed for sensing geomagnetic fields; it is also potentially used for positioning systems based on the geomagnetic field. In this section, some works for DC sensor optimization have been performed, including the different piezo-fibers, driving frequency and magnetic flux concentration. Meanwhile, the lock-in circuit is designed for the magnetic sensor to replace of the commercial instruments. Finally, the man-portable multi-axial geomagnetic sensor has been developed which has the highest resolution of 10 nT for DC magnetic field. Based on the geomagnetic sensor, some demonstrations have been finished, such as orientation monitor, magnetic field mapping, and geomagnetic sensing. Other devices have been also developed besides the magnetic sensor: (i) magnetic energy harvesters are developed under the resonant frequency condition. Especially, one 60 Hz magnetic harvester is designed which can harvester the magnetic energy source generated by instruments; and (ii) frequency multiplication tuned by geomagnetic field is investigated which potentially can be used for frequency multiplier or geomagnetic guidance devices. / Ph. D.

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Yes / Archaeomagnetic dating offers a valuable chronological tool for archaeological investigations, particularly for dating fired material. The method depends on the establishment of a dated record of secular variation of the Earth's magnetic field and this paper presents new and updated archaeomagnetic directional data from the UK and geomagnetic secular variation curves arising from them. The data are taken from publications from the 1950's to the present day; 422 dated entries derived from existing archaeo and geomagnetic databases are re-evaluated and 487 new directions added, resulting in 909 entries with corresponding dates, the largest collection of dated archaeomagnetic directions from a single country. An approach to improving the largest source of uncertainty, the independent dating, is proposed and applied to the British Iron Age, resulting in 145 directions from currently available databases being updated with revised ages and/or uncertainties, and a large scale reassessment of age assignments prior to inclusion into the Magnetic Moments of the Past and GEOMAGIA50 databases. From the significantly improved dataset a new archaeomagnetic dating curve for the UK is derived through the development of a temporally continuous geomagnetic field model, and is compared with previous UK archaeomagnetic dating curves and global field models. The new model, ARCH-UK.1 allows model predictions for any location in the UK with associated uncertainties. It is shown to improve precision and accuracy in archaeomagnetic dating, and to provide new insight into past geomagnetic field changes. / Arts and Humanities Research Council

With the application of new technological trends and principles of scientific research in general, places on environmental influences (everything what surrounds human - building interior and exterior materials, urban areas) and also with sustainable development and ecology, etc., and on health and psychological well-being humans and thus puts on architecture and building entirely new demands on the application of new principles. Due to global climate change, which recently published the official report of the International Panel on Climate Change (IPCC), are placed on reducing the emissions into the atmosphere greater demands on. If architects previously were requested by the client, building with optimal solutions and functional expression of aesthetic quality, so now in addition to increasing demand on building´s solution with low power consumption using environmentally friendly materials from renewable resources and completely satisfying idea of sustainable development. Global societal trends is reverting to the traditional approaches to creating an environment (the application of natural materials, Feng Shui, Building Biology, etc.). The growing trend in today's society on issues of sustainable development, conservation of natural conditions, examining the effects of construction on human health and psychological well-being, which the aims bring together experts seemingly unrelated fields such as geophysics, medicine, architecture, civil engineering, etc., and their findings, according to aspects of the disciplines draw general rules of healthy living. Emerging and still evolving field aims to examine the relationship between man and his environment. The logical starting point is therefore in the context of examining the structure of the first dwelling. Buildings where people spend at least one third of their life. Building, whose location, orientation, mass, materials used in building itself as well as those that surround people in the interior, and many others will affect the physical and physiological action. Not only health but also mental well-being of man is as much determined by a whole range of relationships and linkages. Structural system guidelines for healthy living is the main reason of the work, clear what assumptions we have taken into account in the design and how it specifically relates to a quality place to rest – the Geomagnetic field is one of the base point, which lead to healthy living. Interaction of architecture and geomagnetic field and their values are processed in the evaluation system. It would lead to clarification of the relationship between the occurrence of these anomalies and building materials, construction, site selection for construction of buildings and other solutions. I will desribing the relationship between human´s health and the incidence of these artificial or natural anomalies at the same time.

<p>Three long sediment cores (BDP-98 – 600 m, BDP-96 – 200 m and BDP-93 – 100 m) drilled in Lake Baikal (Siberia) have been studied with the aims of establishing an absolute chronology and reconstructing paleoclimatic and paleoenvironmental changes in the region. The location of the lake at relatively high latitude and continental interior and a thick continuous sedimentary archive that developed in a rift system tectonic setting provide unique material for this investigation. The cosmogenic isotope ¹⁰Be was used for dating and the results indicate time spans of 8 (+0.8\-0.6) Myr for BDP-98, 5.5 (±0.13) Myr for BDP-96 and >0.7 Myr for BDP-93. Two major sedimentary facies (deltaic and hemipelagic) are distinguished by textural geochemical and mineralogical data. Detrital mineral composition suggests negligible change in provenance during the period studied. Formation of authigenic minerals, such as framboidal pyrite, vivianite and siderite, reflects variable environmental conditions in the lake and climate change in the region. Biogenic silica content shows climatic influence, which is modified by the supply of detrital material and postdepositional alterations. ¹⁰Be dating, combined with lithological analysis of the sediments, makes it possible to place temporal constrains on climate cooling at the Miocene/Pliocene boundary (5 Myr ago) and at the Early/Late Pliocene boundary (3.6 Myr ago) as well as the beginning of the northern hemisphere glaciation at about 2.5–2.6 Myr ago. The regional east-west tectonic extension of south-east Asia, related to Tibetan Plateau uplift, was confined in the Baikal area to between about 7 and 5 Myr ago, with a rifting rate calculated at 7 mm year^-1. Furthermore, the ¹⁰Be data suggest that geomagnetic field intensity strengthened around the Miocene/Pliocene boundary.</p>

Three long sediment cores (BDP-98 – 600 m, BDP-96 – 200 m and BDP-93 – 100 m) drilled in Lake Baikal (Siberia) have been studied with the aims of establishing an absolute chronology and reconstructing paleoclimatic and paleoenvironmental changes in the region. The location of the lake at relatively high latitude and continental interior and a thick continuous sedimentary archive that developed in a rift system tectonic setting provide unique material for this investigation. The cosmogenic isotope 10Be was used for dating and the results indicate time spans of 8 (+0.8\-0.6) Myr for BDP-98, 5.5 (±0.13) Myr for BDP-96 and &gt;0.7 Myr for BDP-93. Two major sedimentary facies (deltaic and hemipelagic) are distinguished by textural geochemical and mineralogical data. Detrital mineral composition suggests negligible change in provenance during the period studied. Formation of authigenic minerals, such as framboidal pyrite, vivianite and siderite, reflects variable environmental conditions in the lake and climate change in the region. Biogenic silica content shows climatic influence, which is modified by the supply of detrital material and postdepositional alterations. 10Be dating, combined with lithological analysis of the sediments, makes it possible to place temporal constrains on climate cooling at the Miocene/Pliocene boundary (5 Myr ago) and at the Early/Late Pliocene boundary (3.6 Myr ago) as well as the beginning of the northern hemisphere glaciation at about 2.5–2.6 Myr ago. The regional east-west tectonic extension of south-east Asia, related to Tibetan Plateau uplift, was confined in the Baikal area to between about 7 and 5 Myr ago, with a rifting rate calculated at 7 mm year-1. Furthermore, the 10Be data suggest that geomagnetic field intensity strengthened around the Miocene/Pliocene boundary.

In this work, I will describe a new statistical tool: the canonical bicoherence, which is a combination of the canonical coherence and the bicoherence. I will provide its definitions, properties, estimation by multitaper methods and statistics, and estimate the variance of the estimates by the weighted jackknife method. I will discuss its applicability and usefulness in nonlinear quadratic phase coupling detection and analysis for multivariate random processes. Furthermore, I will develop the time-varying canonical bicoherence for the nonlinear analysis of non-stationary random processes. In this thesis, the canonical bicoherence is mainly applied in two types of data: a) three-component geomagnetic field data, and b) high-dimensional brain electroencephalogram data. Both results obtained will be linked with physical or physiological interpretations. In particular, this thesis is the first work where the novel method of ``canonical bicoherence'' is introduced and applied to the nonlinear quadratic phase coupling detection and analysis for multivariate random processes. / Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2008-10-31 15:03:57.596