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Pohledy na leváctví ve světě / Views on Left-Handedness in the WorldLINHARTOVÁ, Magdaléna January 2010 (has links)
The thesis is aimed at comparing the systems of education and work with left-handed pupils in Germany and the USA (and some other selected countries if need be) and subsequent comparison with the attitude to left-handed individuals prevailing in our country. The thesis is based on a good orientation in specialized literature, contemporary textbooks and guides. The objective rests in mapping the phenomenon of left-handedness in selected countries and its subsequent comparison with the situation in the Czech Republic. The final part of the thesis contains a comprehensive analysis of left-handedness in our country and in the world. The thesis shall highlight differences in viewing this phenomenon in its complexity and outline feasibilities of enriching our views on laterality not only in education.
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Metamaterial stepped impedance resonator filters for wireless communication systemsKarimian, Shokrollah January 2011 (has links)
This thesis introduces, for the first time, Stepped Impedance Resonator (SIR) bandpass filters (BPF) based on Composite Right/Left-Handed (CRLH) transmission lines. In other words, a novel approach in design of BPFs for RF and microwave applications is successfully proposed and examined, which can serve both miniaturisation and performance enhancement purposes. In conducting this research, design, development and optimisation procedures and techniques for the proposed BPFs have been presented. Theoretical, numerical and experimental results have confirmed that these filters are capable of significantly reducing the size while maintaining the integrity of the filter performance; and in some cases, extensively enhancing the performance.Two λg/4-type CRLH SIRs are designed and characterised based on the available equations. ADS lumped-element equivalent circuit model and HFSS full-wave electromagnetic simulation, and measurement results prove that both CRLH SIRs surpassed their RH counterparts, in terms of both size and performance. Indeed, comparison of the first CRLH SIR with its RH counterpart revealed a 35% size (length) reduction. The second CRLH SIR design is measured to be 66% smaller than its RH counterpart and 14% smaller than the initial CRLH SIR. In addition, simulation and measurement results reveal that an intelligently designed CRLH SIR shows a better quality factor Q and input impedance |Zin| response, and provides higher design flexibility. Phase unwrapping and energy (current) flow analysis have been used to prove left-handedness of the CRLH SIRs. The concept is extended to propose multi-section (λg/2-type and tri-section SIRs) and tunable CRLH SIRs. Numerical analysis and obtained results show that the λg/2-type CRLH SIR benefits from a 45% size (length) reduction compared to its RH counterpart, and a better |Zin| response. The results obtained from the tri-section CRLH SIR (TSSIR), clearly show that the TSSIR is capable of relocating (and minimising) the multiple spurious resonance frequencies, while maintaining the same fundamental frequency f0. As such, no spurious frequency is observed before 8 GHz. Also, measurements indicated that the CRLH TSSIR is not only 30% smaller in length compared to its RH counterpart, it was even 28% smaller than a two-section RH SIR resonating at the same frequency of 2.5 GHz. In addition, the tuning capability of the ferrite CRLH SIR is illustrated when the operating frequency of the resonator is tuned from 5.1 GHz to 5.4 GHz, and 5.65 GHz for H0 = 2000, 2250, and 2500 Oe, respectively.These SIRs are then combined and configured to form two main categories of CRLH SIR bandpass filters: PCB filters based on RT Duroid and MMIC filters based on GaAs. In both filters, the homogeneity condition has been satisfied by ensuring that the longest length is much less than λg (in this case l = λg/12) for PCB-based filters and l = λg/14 for MMIC filters at the centre frequency of the filters. The first PCB-based CRLH SIR filter, which has been designed to operate at 2.75 GHz, is measured 24mm × 28mm. HFSS 3-D full-wave simulations and measurement results of this filter reveal that, with an insertion loss of -2.6dB and return loss of -21.5dB, the filter not only has a very good selectivity, but also is extremely efficient in extending the free-spurious stop-band, pushing the first spurious response to around 11 GHz (about 4×f0). The second PCB-based CRLH SIR filter has much smaller size, measuring overall filter dimensions of 6mm × 5.14mm. This filter also benefits from a smaller resonator size, improved overall coupling and a more controllable circuit. Theory, full-wave simulation and measurement results demonstrate that, with an insertion loss of -1dB and return loss of -34dB, the miniaturised CRLH SIR filter proves very successful as it was about 80% smaller in size compared to its RH counterpart with the same centre frequency, while maintaining the integrity of the filter performance. Moreover, the miniaturised CRLH SIR BPF is significantly more controllable in its dimensions and response due to the fact that more elementary parameters are available in the CRLH configuration.The MMIC CRLH SIR bandpass filters are then proposed with an emphasis on further size reduction with maintenance (or enhancement) of their transmission responses. As such, two classes of MMIC filters were designed: the first one is very small measuring 3.2mm × 3.4mm, with an insertion loss of -5.3dB at the centre frequency 3.1 GHz. The filter also shows good attenuation both before and after the passband with its first spurious frequency occurring at 13.52 GHz (i.e. > 4×f0). The second set of MMIC filters employed multilayer topology to reduce the filter size. It has been clearly shown that with an intelligent design, the size (dimension) limitations of the PCB-based filters have been overcome by using the MMIC technology, resulting in filters with significantly reduced sizes - design I: 1.32mm×3.35mm, and design II: 1.4mm × 1.5mm. It has also been observed that MMIC structures are generally exposed to inevitable losses, though steps can be taken to reduce such losses.
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Zeroth-Order Resonator (ZOR) Antenna Using Composite Right/Left-Handed (CRLH ) Microstrip Transmission Line (TL)Shi, Ruirong 02 May 2011 (has links)
No description available.
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K problematice leváctví / The issue of left-handednessGROBHEISEROVÁ, Petra January 2014 (has links)
The theses The issue of left-handedness focuses on left-handedness at its complexity. The theoretical part is focused on laterality and the left-handedness in general, the place of left-handed people in society and the changing view on laterality during times. It focuses on the differences between left and right-handed people and points out possible difficulties the left-handed might face. At the end I dealt with testing laterality and focused on possible ways to guide left-handed pupils. The practical research part is based on finding out the number of left-handed pupils in 1st grades on schools in the Karlovy Vary region. I farther focused on how aware of the lefthanded pupils problems the teachers are and how they guide them. The research took part in 16 randomly picked schools.
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Applications of Structural Bioinformatics for the Structural Genomics EraNovotny, Marian January 2007 (has links)
<p>Structural bioinformatics deals with the analysis, classification and prediction of three-dimensional structures of biomacromolecules. It is becoming increasingly important as the number of structures is growing rapidly. This thesis describes three studies concerned with protein-function prediction and two studies about protein structure validation.</p><p>New protein structures are often compared to known structures to find out if they have a known fold, which may provide hints about their function. The functionality and performance of eleven fold-comparison servers were evaluated. None of the tested servers achieved perfect recall, so in practise a combination of servers should be used.</p><p>If fold comparison does not provide any hints about the function of a protein, structural motif searches can be employed. A survey of left-handed helices in known protein structures was carried out. The results show that left-handed helices are rare motifs, but most of them occur in active or ligand-binding sites. Their identification can therefore help to pinpoint potentially important residues.</p><p>Sometimes all available methods fail to provide hints about the function of a protein. Therefore, the potential of using docking techniques to predict which ligands are likely to bind to a particular protein has been investigated. Initial results show that it will be difficult to build a reliable automated docking protocol that will suit all proteins.</p><p>The effect of various phenomena on the precision of accessible surface area calculations was also investigated. The results suggest that it is prudent to report such values with a precision of 50 to 100 Å<sup>2</sup>.</p><p>Finally, a survey of register shifts in known protein structures was carried out. The identified potential register shifts were analysed and classified. A machine-learning approach ("rough sets") was used in an attempt to diagnose register errors in structures.</p>
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Applications of Structural Bioinformatics for the Structural Genomics EraNovotny, Marian January 2007 (has links)
Structural bioinformatics deals with the analysis, classification and prediction of three-dimensional structures of biomacromolecules. It is becoming increasingly important as the number of structures is growing rapidly. This thesis describes three studies concerned with protein-function prediction and two studies about protein structure validation. New protein structures are often compared to known structures to find out if they have a known fold, which may provide hints about their function. The functionality and performance of eleven fold-comparison servers were evaluated. None of the tested servers achieved perfect recall, so in practise a combination of servers should be used. If fold comparison does not provide any hints about the function of a protein, structural motif searches can be employed. A survey of left-handed helices in known protein structures was carried out. The results show that left-handed helices are rare motifs, but most of them occur in active or ligand-binding sites. Their identification can therefore help to pinpoint potentially important residues. Sometimes all available methods fail to provide hints about the function of a protein. Therefore, the potential of using docking techniques to predict which ligands are likely to bind to a particular protein has been investigated. Initial results show that it will be difficult to build a reliable automated docking protocol that will suit all proteins. The effect of various phenomena on the precision of accessible surface area calculations was also investigated. The results suggest that it is prudent to report such values with a precision of 50 to 100 Å2. Finally, a survey of register shifts in known protein structures was carried out. The identified potential register shifts were analysed and classified. A machine-learning approach ("rough sets") was used in an attempt to diagnose register errors in structures.
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Design and Application of Left-Handed Metamaterial-Based Negative Group Delay Circuits and Filters with High Selectivity Based on Composite Right/Left-Handed StructureLin, Chia-Chi 26 July 2011 (has links)
In a communication system, the group delay variation (GDV) causes the distortion of signal and the degradation of symbol error rate. Usually, the compensation of group delay (GD) utilizing positive group delay (PGD) results in further propagation delay. Therefore, this research studies the negative group delay (NGD) behavior of metamaterial. Through analyzing the effects on GD caused by poles and zeros of circuit, the group delay circuit capable of switching between NGD and PGD is presented. Further, adjustable negative group delay circuits (NGDCs) are designed based on the concept of poles and zero. The NGD generated by NGDC is used to achieve the equalization of GD and recover the distorted signal in time domain.
Additionally, owing to the limited frequency band of communication, a filter with high selectivity is required to utilize the available bandwidth. The character of left-handed metamaterial is applied to the design of filter for reducing the size and cost of traditional microstrip line filters with high selectivity. Under the balanced condition, composite right/left-handed (CRLH) transmission line behaves right- and left- handed characteristics in different frequency bands. Thus, a coplanar waveguide (CPW) filter with high selectivity, size reduction and low cost is presented utilizing such a CRLH structure.
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Transmission Properties Of Fishnet Structure As A Left Handed MetamaterialBilge, Serafettin 01 March 2009 (has links) (PDF)
Left handed metamaterials are one of the most populer topic attracting attentions of scientists nowadays. Metamaterials are engineered materials which can possess inordinary properties when compared with common materials existing in nature. The main structure investigated in this thesis is fishnet metamaterial which is a left handed metamaterial. Firstly some left handed metamaterials and their properties are surveyed. A retrieval procedure in order to obtain permittivity, permeability and refractive index of any periodic material was summarized. Left handedness of fishnet structure was investigated and proven numerically. Effects of change in polarization of an incoming wave to symmetric and asymmetric fishnet structure were searched. A parametric analysis of fishnet structure was done. Phase advance in a three layered fishnet structure was investigated and compared with phase advance in an ordinary material. Fishnet wedge structure was surveyed and negative refraction and negative phase advance in this structure are shown. Finally, some types of disorderness of fishnet structure, then its effects on transmission results and retrieval results are demonstrated. In order to obtain transmission and reflection through a material, CST Microwave Studio® / was used. A code following a numerical procedure in order to retrieve constitutive parameters of a periodic structure which was written in Matlab® / was used in this thesis.
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Handedness & Autobiographical Memory: An Examination of Handedness and its Effects on Autobiographical MemoryGosch, Austin 01 January 2018 (has links)
Previous research has shown that individuals who are inconsistently handed (IH) outperform consistently handed (IH) individuals on episodic and spatial memory tasks as well as many others. This current study examines whether handedness is related to a person’s ability to recall autobiographical memories (AM) - episodic memories about oneself. Participants were first asked to recall seven memories that will be cued by seven cue words: earth, friend, dream, power, love, trouble, and opinion. They later expanded on those memories to include more detail, then self-rated how well they were able to remember them on five aspects of AM (spatial layout, content, reliving, vividness, and belief) using a modified version of the Autobiographical Memory Questionnaire (AMQ). Ninety-seven participants (44.3% female, Age: 19 to 69 years) were included in the data analysis. All ninety-seven were recruited through Amazon’s Mechanical Turk system and were financially compensated for their time. Results showed no main effect of handedness on AM in regards to all five AM aspects tested, meaning IH’s did not outperform CH’s in regards to autobiographical memory recall.
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Structures exotiques en nanophotonique, théorie et approche numérique / Exotic structures in nanophotonics, theory and numerical approachPollès, Rémi 10 June 2011 (has links)
Dans la perspective d’un contrôle ultime de la lumière, les arrivées récentes des cristaux photoniques et des métamatériaux constituent des avancées majeures. Ces matériaux nano-structurés présentant des propriétés optiques inédites nous ouvrent tout un champ de possibilités encore inexploré. En particulier, des milieux d’indice effectif négatif sont rendus concevables. L’objectif de cette thèse est d’étudier d’un point de vue électromagnétique, à l’aide d’outils analytiques et numériques, le comportement de la lumière dans ces structures exotiques. Nous nous penchons sur les boucles de lumières, qui sont des modes localisés d’une structure multi-couches, émergeant du couplage contra-directionnel entre deux guides distincts. Une analyse physique est proposée et un modèle basé sur la théorie des modes couplés est développé. Cela nous permet de décrire avec précision l’excitation d’une boucle de lumière par une source lumineuse, et d’envisager des applications pour la mise en forme de faisceau. Dans une seconde partie, nous étudions des cristaux photoniques unidimensionnels formés par une alternance de milieux d’indices positif et négatif. Lorsque l’indice moyen est nul, une bande interdite aux propriétés nouvelles apparait. Nous montrons que le caractère dispersif des milieux transforme des pics étroits de transmission en larges bandes. Pour caractériser la propagation d’un faisceau dans un tel cristal, nous développons et validons alors un modèle qui nous permet de démontrer le potentiel en matière de mise en forme de faisceau (auto-collimation, focalisation). / In the perspective of an ultimate control of light, the recent arrivals of photonic crystals and metamaterials are major advances. These nano-structured materials with unusual optical properties are opening a whole range of possibilities still unexplored. In particular, negative index media have became conceivable. The aim of this thesis is to study, with an electromagnetic point of view, the behavior of light in these exotic structures, using analytical and numerical tools. We study the light wheels, which are localized modes of a multi-layer structure, emerging from the contra-directional coupling between two separate waveguides. A physical analysis is proposed and a model, based on the coupled mode theory, is developed. This allows us to accurately describe the excitation of a light wheel by a source, and to consider applications for beam shaping. In a second part, we study one-dimensional photonic crystals combining positive and negative index layers whose the average index is equal to zero. A band gap, called zero-n gap, appears and presents new properties that we detail. Index dispersion is shown to broaden the resonant frequencies creating then a conduction band lying inside the zero-n gap. Self-collimation and focusing effects are in addition demonstrated in zero-average index crystals supporting defect modes. This beam shaping is explained in the framework of a beam propagation model by introducing an harmonic average index parameter.
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