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Engineering of Nanoparticles for Luminescence SwitchingImpellizzeri, Stefania 02 February 2012 (has links)
Fluorescence microscopy offers the opportunity to image biological samples noninvasively in real time and has become an essential analytical tool in the biomedical laboratory. Nonetheless, the phenomenon of diffraction imposes stringent limitations on the resolving power of conventional microscopes, preventing the spatial resolution of fluorescent species co-localized within areas of nanoscaled dimensions. Time, however, can be exploited to distinguish fluorophores within the same subdiffraction area, if their fluorescence can be switched independently, and reconstruct sequentially their spatial distribution. In this context, photolytic reactions and photochromic transformations can be invoked to switch fluorescence under optical control. Fluorescent units, such as inorganic semiconductor nanoparticles and organic dyes, and photoactive components can be operated within a common supramolecular matrix or integrated within the same molecular construct to produce photoswitchable fluorescent assemblies. In the resulting systems, electronic communication between the components can be designed in order to photoactivate or photodeactivate fluorescence respectively. Both mechanisms can be exploited to overcome diffraction, and ultimately permit the reconstruction of images with resolution down to the nanometer level, in combination with appropriate illumination protocols.
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重力と非線形ばね特性の作用を受ける偏平軸の振動 (調和型振動と超和差型振動)石田, 幸男, ISHIDA, Yukio, 井上, 剛志, INOUE, Tsuyoshi, 劉, 軍, LIU, Jun, 鈴木, 昭宏, SUZUKI, Akihiro 05 1900 (has links)
No description available.
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Amalgamating tribunals: a recipe for optimal reformBacon, Rachel January 2004 (has links)
The last decade has seen numerous proposals to reform existing tribunal systems in jurisdictions throughout the common law world. Across the board, there have been proposals to adopt generalist tribunal models in preference to smaller, specialist tribunal systems, and to achieve these changes through the process of amalgamation. The most significant recent developments to occur in Australia have taken place in Victoria and NSW during the past five years. Legislators in these States have chosen to amalgamate a number of smaller, specialist tribunals into larger, generalist bodies. In 1997 the NSW Parliament passed legislation amalgamating a number of specialist tribunals to create the Administrative Decisions Tribunal (ADT); comparable legislation was passed in Victoria in 1998 to create the Victorian Civil and Administrative Tribunal (VCAT). There were concurrent attempts to implement similar reforms at federal level. In 1998 the Commonwealth government announced its intention to amalgamate four Commonwealth merits review tribunals to form one �super Tribunal� � the Administrative Review Tribunal (ART). The Bills containing these proposals were ultimately defeated in the Senate, however the Australian Government remains convinced of the benefits of amalgamation at federal level. Similar reforms have been proposed in Western Australia, Tasmania and the United Kingdom. This thesis argues that these reforms are taking place in the absence of data about their likely implications, and without a thorough understanding of the objectives that generalist versus specialist tribunal systems can realistically achieve. This ill-considered or �over-hasty� trend towards amalgamation raises a number of questions which have not previously been addressed in academic or policy-making circles. An obvious question is whether or not an amalgamated tribunal model is more effective than a series of smaller, specialised tribunals in delivering administrative justice, in other words, whether there is any net gain to be had from a government�s decision to amalgamate. The less explored, but equally important, question addressed in this thesis is how the process of amalgamation should be approached in order to realise the maximum potential benefits that an amalgamated tribunal can bring. That is, to ask what are the ingredients of an optimal amalgamation. This is not a question about whether government decisions to pursue amalgamation are intrinsically worthwhile or beneficial for stakeholders. Rather, it is about how government decisions to amalgamate should best be implemented. This thesis proposes a way of differentiating between good and bad amalgamations, that is grounded in theory and informed by experience to date. The proposed approach is to assess the effectiveness of amalgamation processes using relevant measures drawn from an analysis of organisational theory literature: � Legislation � the legislation establishing an amalgamated tribunal needs to ensure the tribunal will have appropriate independence, powers, processes, membership and structure. � Political commitment � those responsible for proposing and planning an amalgamation need to provide appropriate funding and support for the process and for the establishment of an autonomous, self-directed tribunal. � Organisational structure � the structures put in place need to be appropriate, integrated and flexible, and should promote cohesion and interaction. � Process and procedure � the processes and procedures adopted in an amalgamated tribunal need to capitalise upon the opportunities provided by amalgamation, as well as being appropriate, efficient and able to balance the needs of a range of stakeholders. � Organisational culture � an organisational culture which counters natural tendencies towards disjunction will assist members and staff to identify with a newly amalgamated tribunal and to implement initiatives that will improve its performance. � Leadership � effective leadership plays an important role in ensuring a smooth transition from specialist to amalgamated tribunal, and engendering commitment from members and staff. Broadly speaking, these factors fall into the four categories of law, context, organisation and people. It is argued that attention must be paid to all four of these ingredients in order to achieve optimal tribunal reform. The thesis tests this proposition by examining the three most advanced tribunal amalgamations so far, namely, the Commonwealth ART, the NSW ADT and VCAT in Victoria. It is argued that the fate of the Commonwealth ART proposal proves the importance of a solid, generally endorsed legislative foundation in creating a viable amalgamated tribunal. The importance of context, organisation and people is borne out by qualitative research into the amalgamation experiences in NSW and Victoria. The fact that the NSW and Victorian governments decided to pursue policies of amalgamation at the same time provided a unique opportunity to compare the success or otherwise of two concurrent attempts at amalgamation in different jurisdictions. This thesis finds that the unfavourable political context in NSW prevented the ADT from realising its potential. In contrast, the VCAT experience highlights the benefits of paying careful attention to the wide range of factors that can contribute to a successful amalgamation. Of most relevance are the initial scale of an amalgamation, the political �will� behind its implementation, the appointment of a core of full-time members, and the creation of an open institutional culture which facilitates the sharing of information. In short, the thesis concludes that the successful construction and consolidation of a tribunal post-amalgamation requires that the necessary ingredients of optimal tribunal reform � legislation, context, organisation and people � are thoughtfully addressed.
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Catalyzed Big Bang Nucleosynthesis and the properties of charged relics in the early universeKoopmans, Kristen Alanna 27 August 2007 (has links)
The existence of charged electroweak-scale particles in the early universe can drastically affect the evolution of elemental abundances. Through the formation of Coulombic bound states with light nuclei, these exotic relic particles (hereafter referred to as X–) act to catalyze nuclear reactions by reducing their threshold energies. This thesis examines the properties of the X– bound states, and uses primordial element observations to constrain the abundance, lifetime, and mass of this exotic particle species. If the X– is a Dirac Fermion, its abundance relative to baryons is found to be YX- ~ 0.01, with a lifetime of 1500s ≤ τX- ≤ 3000s, and a mass of order 100 GeV. Assuming that the X– is a Scalar particle that decays into gravitinos, the resulting bounds become, 5x10-4 ≤ YX- ≤ 0.07, 1600s ≤ τX- ≤ 7000s, and 60GeV ≤ mX- ≤ 1000GeV. These ranges are consistent with Dark Matter constraints.
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Towards a systematic investigation of weakly coupled free fermionic heterotic string gauge group statisticsRobinson, Matthew Brandon, Cleaver, Gerald B. January 2009 (has links)
Thesis (Ph.D.)--Baylor University, 2009. / Includes bibliographical references (p. 124-130).
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Μέθοδοι βελτίωσης της χωρικής ανάλυσης ψηφιακής εικόναςΠαναγιωτοπούλου, Αντιγόνη 12 April 2010 (has links)
Η αντιμετώπιση της περιορισμένης χωρικής ανάλυσης των εικόνων, η οποία οφείλεται στους φυσικούς περιορισμούς που εμφανίζουν οι αισθητήρες σύλληψης εικόνας, αποτελεί το αντικείμενο μελέτης της παρούσας διδακτορικής διατριβής. Στη διατριβή αυτή αρχικά γίνεται προσπάθεια μοντελοποίησης της λειτουργίας του ψηφιοποιητή εικόνας κατά τη δημιουργία αντίγραφου ενός εγγράφου μέσω απλών μοντέλων. Στην εξομοίωση της λειτουργίας του ψηφιοποιητή, το προτεινόμενο μοντέλο θα πρέπει να προτιμηθεί έναντι των μοντέλων Gaussian και Cauchy, που συναντώνται στη βιβλιογραφία, καθώς είναι ισοδύναμο στην απόδοση, απλούστερο στην υλοποίηση και δεν παρουσιάζει εξάρτηση από συγκεκριμένα χαρακτηριστικά λειτουργίας του ψηφιοποιητή.
Έπειτα, μορφοποιούνται νέες μέθοδοι για τη βελτίωση της χωρικής ανάλυσης σε εικόνες. Προτείνεται μέθοδος μη ομοιόμορφης παρεμβολής για ανακατασκευή εικόνας Super-Resolution (SR). Αποδεικνύεται πειραματικά πως η προτεινόμενη μέθοδος η οποία χρησιμοποιεί την παρεμβολή Kriging υπερτερεί της μεθόδου η οποία δημιουργεί το πλέγμα υψηλής ανάλυσης μέσω της σταθμισμένης παρεμβολής κοντινότερου γείτονα που αποτελεί συμβατική τεχνική. Επίσης, παρουσιάζονται τρεις νέες μέθοδοι για στοχαστική ανακατασκευή εικόνας SR regularized. Ο εκτιμητής Tukey σε συνδυασμό με το Bilateral Total Variation (BTV) regularization, ο εκτιμητής Lorentzian σε συνδυασμό με το BTV regularization και ο εκτιμητής Huber συνδυασμένος με το BTV regularization είναι οι τρεις μέθοδοι που προτείνονται. Μία πρόσθετη καινοτομία αποτελεί η απευθείας σύγκριση των τριών εκτιμητών Tukey, Lorentzian και Huber στην ανακατασκευή εικόνας super-resolution, άρα στην απόρριψη outliers. Η απόδοση των προτεινόμενων μεθόδων συγκρίνεται απευθείας με εκείνη μίας τεχνικής SR regularized που υπάρχει στη βιβλιογραφία, η οποία αποδεικνύεται κατώτερη. Σημειώνεται πως τα πειραματικά αποτελέσματα οδηγούν σε επαλήθευση της θεωρίας εύρωστης στατιστικής συμπεριφοράς.
Επίσης, εκπονείται μία πρωτότυπη μελέτη σχετικά με την επίδραση που έχει κάθε ένας από τους όρους έκφρασης πιστότητας στα δεδομένα και regularization στη διαμόρφωση του αποτελέσματος της ανακατασκευής εικόνας SR. Τα συμπεράσματα που προκύπτουν βοηθούν στην επιλογή μίας αποτελεσματικής μεθόδου για ανακατασκευή εικόνας SR ανάμεσα σε διάφορες υποψήφιες μεθόδους για κάποια δεδομένη ακολουθία εικόνων χαμηλής ανάλυσης. Τέλος, προτείνεται μία μέθοδος παρεμβολής σε εικόνα μέσω νευρωνικού δικτύου. Χάρη στην προτεινόμενη τεχνική εκπαίδευσης το νευρωνικό δίκτυο μαθαίνει το point spread function του ψηφιοποιητή εικόνας. Τα πειραματικά αποτελέσματα αποδεικνύουν πως η προτεινόμενη μέθοδος υπερτερεί σε σχέση με τους κλασικούς αλγόριθμους δικυβικής παρεμβολής και παρεμβολής spline. Η τεχνική που προτείνεται εξετάζει για πρώτη φορά το ζήτημα της σειράς της παρουσίασης των δεδομένων εκπαίδευσης στην είσοδο του νευρωνικού δικτύου. / Coping with the limited spatial resolution of images, which is caused by the physical limitations of image sensors, is the objective of this thesis. Initially, an effort to model the scanner function when generating a document copy by means of simple models is made. In a task of scanner function simulation the proposed model should be preferred over the Gaussian and Cauchy models met in bibliography as it is equivalent in performance, simpler in implementation and does not present any dependence on certain scanner characteristics.
Afterwards, new methods for improving images spatial resolution are formulated. A nonuniform interpolation method for Super-Resolution (SR) image reconstruction is proposed. Experimentation proves that the proposed method employing Kriging interpolation predominates over the method which creates the high-resolution grid by means of the weighted nearest neighbor interpolation that is a conventional interpolation technique. Also, three new methods for stochastic regularized SR image reconstruction are presented. The Tukey error norm in combination with the Bilateral Total Variation (BTV) regularization, the Lorentzian error norm in combination with the BTV regularization and the Huber error norm combined with the BTV regularization are the three proposed methods. An additional novelty is the direct comparison of the three estimators Tukey, Lorentzian and Huber in the task of super-resolution image reconstruction, thus in rejecting outliers. The performance of the proposed methods proves superior to that of a regularized SR technique met in bibliography. Experimental results verify the robust statistics theory.
Moreover, a novel study which considers the effect of each one of the data-fidelity and regularization terms on the SR image reconstruction result is carried out. The conclusions reached help to select an effective SR image reconstruction method, among several potential ones, for a given low-resolution sequence of frames. Finally, an image interpolation method employing a neural network is proposed. The presented training procedure results in the network learning the scanner point spread function. Experimental results prove that the proposed technique predominates over the classical algorithms of bicubic and spline interpolation. The proposed method is novel as it treats, for the first time, the issue of the training data presentation order to the neural network input.
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Αύξηση της χωρικής ανάλυσης για βελτίωση της ποιότητας των εικόνων (super resolution imaging)Μπακούλιας, Κωνσταντίνος 20 April 2011 (has links)
Η επεξεργασία εικόνας πλέον είναι απαραίτητη σε ένα μεγάλο πεδίο εφαρμογών που χρησιμοποιούν εκατομμύρια χρήστες σε όλο τον κόσμο. Σίγουρα οι αισθητήρες σύλληψης της εικόνας έχουν βελτιωθεί κατά πολύ με την ραγδαία εξέλιξη που έχει ο χώρος των ηλεκτρονικών. Η ελαττωμένη χωρική ανάλυση των εικόνων οφείλεται στους περιορισμούς που εμφανίζουν οι αισθητήρες. Η αύξηση της χωρικής ανάλυσης είναι και το αντικείμενο της παρούσας εργασίας.
Στην εργασία αυτή μελετήσαμε διάφορες τεχνικές με τις οποίες προσπαθούμε να αυξήσουμε την χωρική ανάλυση για να βελτιώσουμε την ποιότητα της εικόνας [1]. Η υλοποίηση της έγινε με την βοήθεια των εκτιμητών πυκνότητας πιθανότητας (Kernels). Ως συγκριτική μέθοδος χρησιμοποιήσαμε την συνάρτηση παρεμβολής του matlab (interp2) [8]. Επίσης, το μέσω τετραγωνικό σφάλμα ( Mean Square Error ) και ο μέγιστος λόγος σήματος προς θόρυβο ( Peak Signal to Noise Ratio ) είναι δύο από τους βασικούς τρόπους σύγκρισης της τεχνική μας με την μέθοδο παρεμβολής του matlab.
Θα πρέπει να αναφέρουμε ότι τα αποτελέσματά μας αν και χρησιμοποιήσαμε στατιστικά πρώτης τάξης είναι ικανοποιητικά παραπλήσια της μεθόδου παρεμβολής του matlab. Ως σημείο αναφοράς της σύγκριση της τεχνική μας με την μέθοδο παρεμβολής του matlab είναι η αρχική εικόνα.
Τέλος, στην προσπάθεια μας να βελτιώσουμε την τεχνική μας, δοκιμάσαμε και άλλες τεχνικές, οι οποίες θα περιγραφούν με λεπτομέρεια στην εργασία αυτή, τα αποτελέσματα των οποίων δεν ήταν τα επιθυμητά. / The image processing is now needed in a wide range of applications used by millions of users around the world. Certainly the design of image sensors have improved greatly with the rapid development that has an area of electronics. The reduced spatial resolution of images due to the limitations inherent in the sensors. Increased spatial resolution is the subject of this work.
This thesis reviews various techniques that try to increase the spatial resolution to improve the image quality [1]. Driving done with the help of probability density estimators (Kernels). As a comparative method used the interpolation function of matlab (interp2) [8]. Also, the means square error (Mean Square Error) and the maximum signal to noise ratio (Peak Signal to Noise Ratio) are two basic ways of comparing our technique with the method of interpolation matlab.
It should be mentioned that although our results using statistical first order is approaching a satisfactory method of interpolation matlab. As a benchmark comparison of our technique with the method of interpolation matlab is the original image.
Finally, in our efforts to improve our technique, testing and other techniques, which will be described in detail in this work, the results of which were not desired.
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Μέθοδοι σύνθεσης εικόνων υψηλής ανάλυσης από εικόνες χαμηλότερης ανάλυσηςΚλαρούδας, Ευάγγελος 23 May 2011 (has links)
Στα πλαίσια της διπλωματικής αυτής θα μελετηθεί το πρόβλημα της σύνθεσης
εικόνας υψηλής ανάλυσης, χρησιμοποιώντας πολλαπλές εικόνες χαμηλότερης
ανάλυσης. Η τεχνική αυτή προσφέρει την δυνατότητα μείωσης των αλλοιώσεων
που υπεισέρχονται από τους αισθητήρες καταγραφής των εικόνων
(θόρυβος,θόλωμα), την αύξηση της χωρικής ανάλυσης καθώς και την αύξηση
του δυναμικού εύρους της εικόνας, ώστε να είναι εφικτή η μεγέθυνση της με
ικανοποιητική ποιότητα.
Υπάρχουν δύο κύριες κατηγορίες μεθόδων που θα μελετηθούν. Στην πρώτη
κατηγορία εντάσσονται μεθόδοι που συνθέτουν μία εικόνα τρισδιάστατης
φυσικής σκηνής από χαμηλότερες ανάλυσης εικόνες στις οποίες έχει
αποτυπωθεί τμήμα της. Ο κύριος στόχος των μεθόδων αυτών είναι να
υπολογιστούν οι μετασχηματισμοί ευθυγράμμισης των εικόνων εισόδου. Στην
δεύτερη κατηγορία εντάσσονται στατιστικές μέθοδοι, που προσπαθούν να
αυξήσουν την χωρική ανάλυση ή να βελτιώσουν το δυναμικό εύρος της
εικόνας, με σκοπό την βέλτιστη δυνατή ανάκτηση της φυσικής σκηνής. Ο
κύριος στόχος των μεθόδων που ανήκουν στην κατηγορία αυτή, είναι η
βέλτιστη εκτίμηση των τιμών των εικονοστοιχείων. / This thesis investigates the inverse problem of Super Resolution.
Super Resolution algorithms reduce the effects of noise and blurring
and produce an image of superior quality. This quality ensures that
when we zoom in the image, the image details are not lost.
Super Resolution algorithms are separated into two categories. The
first category studies algorithms which combine overlapping
images of low resolution to produce a panoramic image of the scene.
The second category contains algorithms which produce a high detailed image.
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Non-Canonical Amino Acids as Minimal Tags for Investigating Protein Organization and TurnoverGebura-Vreja, Ingrid-Cristiana 14 October 2015 (has links)
No description available.
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Simulação computacional de materiais com elétrons fortemente interagentes: DMRG aplicado a super-redes Hubbard com modulação de condução entre camadasSimon, Ricardo de Almeida [UNESP] 11 April 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:29Z (GMT). No. of bitstreams: 0
Previous issue date: 2008-04-11Bitstream added on 2014-06-13T19:29:34Z : No. of bitstreams: 1
simon_ra_me_bauru.pdf: 585170 bytes, checksum: 22e864a53f831e4bf21be6c6b81ed2f3 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Na área de pesquisa em sistemas de elétrons fortemente correlacionados, o modelo das super-redes Hubbard tem sido utilizada para explicar e prever comportamentos de heteroestruturas, como multicamadas magnéticas, que apresentam propriedades diferentes e incomuns, comparadas com as dos sistemas homogêneos análogos, E.G., ordenamentos magnéticos e de carga. Neste contexto, foram estudados nesta dissertação os efeitos da introdução de um novo valor , 'T IND. C', para o parâmetro de hopping de elétron nas interfaces de camadas diferentes da super-rede, ou seja, introduziu-se uma modulação na condução entre as camadas. Variou-se 'T IND. C'entre 0.1T e T, onde T é o parâmetro de hopping entre sítios da mesma camada. Para a lacuna de carga encontramos um comportamento dependente da densidade eletrônica na rede. Em geral, momentos magnéticos locais e a ocupação eletrônica nos sítios, apresentam uma distribuição mais uniforme para 'T IND. C'=0.1T. No entanto, nas densidades onde ocorre um aumento abrupto na lacuna de carga com a diminuição de 'T IND. C', essa uniformidade é mais pronunciada, possivelmente devido a uma comensurabilidade entre a distribuição dos elétrons na cadeia e a estrutura da super-rede. Para as funções de correlação de carga, que foram estudadas através do fator de estrutura, encontramos em alguns casos uma dependência em 'T IND. C' do período do ordenamento correspondente. / In the research field of strongly correlated electron systems, the Hubbard superlattice model has been used for explain and predict the behavior of heterostructures, such as magnetic multilayers, whose unusual properties differ from the properties of the analogous homogeneous counterpart. In this context, we have studied here the effects of introducing a new value for the hopping parameter, 'T IND. C', for electrons between different layers, E.G., we introduced a modulation in the electronic conduction between layers. We consider 'T IND. C' in the range 0.1T to T, where T is the hopping parameter for sites inside the layers. For the charge gap, we found a behavior that depends on the electronic density in the lattice. Local magnetic and electronic occupation on sites, generally, show a greater uniformity with decreasing 'T IND. C'. However, for electronic densities where is an abrupt increase in the charge gap for decreasing 'T IND. C', this uniformity is enhanced, probably due to a commensurability between the electronic distribution in the chain and the underlying superlattice structure. For the charge correlation functions, that were studied through their structure factor, we found in some cases a dependency in 'T IND. C' of the correlations oscillation period.
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