914 resultados para COHERENT OTDR


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The recently discovered twist phase is studied in the context of the full ten-parameter family of partially coherent general anisotropic Gaussian Schell-model beams. It is shown that the nonnegativity requirement on the cross-spectral density of the beam demands that the strength of the twist phase be bounded from above by the inverse of the transverse coherence area of the beam. The twist phase as a two-point function is shown to have the structure of the generalized Huygens kernel or Green's function of a first-order system. The ray-transfer matrix of this system is exhibited. Wolf-type coherent-mode decomposition of the twist phase is carried out. Imposition of the twist phase on an otherwise untwisted beam is shown to result in a linear transformation in the ray phase space of the Wigner distribution. Though this transformation preserves the four-dimensional phase-space volume, it is not symplectic and hence it can, when impressed on a Wigner distribution, push it out of the convex set of all bona fide Wigner distributions unless the original Wigner distribution was sufficiently deep into the interior of the set.

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We studied the microstructural evolution of multiple layers of elastically stiff films embedded in an elastically soft matrix using a phase field model. The coherent and planar film/matrix interfaces are rendered unstable by the elastic stresses due to a lattice parameter mismatch between the film and matrix phases, resulting in the break-up of the films into particles. With an increasing volume fraction of the stiff phase, the elastic interactions between neighbouring layers lead to: (i) interlayer correlations from an early stage; (ii) a longer wavelength for the maximally growing wave; and therefore (iii) a delayed break-LIP. Further, they promote a crossover in the mode of instability from a predominantly anti-symmetric (in phase) one to a symmetric (out of phase) one. We have computed a stability diagram for the most probable mode of break-up in terms of elastic modulus Mismatch and Volume fraction. We rationalize our results in terms of the initial driving force for destabilization, and corroborate our conclusions using simulations in elastically anisotropic systems.

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This paper deals with a new form of nonlinear Raman spectroscopy called `ultrafast Raman loss spectroscopy (URLS)'. URLS is analogous to stimulated Raman spectroscopy (SRS) but is much more sensitive than SRS. The signals are background (noise) free unlike in coherent anti-Stokes Raman spectroscopy (CARS) and it provides natural fluorescence rejection, which is a major problem in Raman spectroscopy. In addition, being a self-phase matching process, the URLS experiment is much easier than CARS, which requires specific phase matching of the laser pulses. URLS is expected to be alternative if not competitive to CARS microscopy, which has become a popular technique in applications to materials, biology and medicine.

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Internal motions in a A2BX4 compound (tetramethylammonium tetrabromo cadmate) have been investigated using proton spin—lattice relaxation time (T1) and second moment (M2) measurements in the temperature range 77 to 400 K. T1 measurements at three Larmor frequencies (10, 20 and 30 MHz) show isotropic tumbling of the tetramethylammonium group, random reorientation of methyl groups and spin—rotation interaction, and the corresponding parameters have been computed. The cw spectrum is narrow throughout the temperature range and shows side bands at the lowest temperature. This observation, along with the free-induction-decay behavior at these temperatures, is interpreted as the onset of a coherent motion, e.g. methyl group quantum tunnelling.

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Doppler weather radars with fast scanning rates must estimate spectral moments based on a small number of echo samples. This paper concerns the estimation of mean Doppler velocity in a coherent radar using a short complex time series. Specific results are presented based on 16 samples. A wide range of signal-to-noise ratios are considered, and attention is given to ease of implementation. It is shown that FFT estimators fare poorly in low SNR and/or high spectrum-width situations. Several variants of a vector pulse-pair processor are postulated and an algorithm is developed for the resolution of phase angle ambiguity. This processor is found to be better than conventional processors at very low SNR values. A feasible approximation to the maximum entropy estimator is derived as well as a technique utilizing the maximization of the periodogram. It is found that a vector pulse-pair processor operating with four lags for clear air observation and a single lag (pulse-pair mode) for storm observation may be a good way to estimate Doppler velocities over the entire gamut of weather phenomena.

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Empty Heavens. Georges Bataille and the Question of Religion. The dissertation explores the question of religion in the texts of Georges Bataille (1897 1962), the controversial French avant-garde writer and philosopher. Passionate about religion throughout his life, Bataille devoted to it both critical analyses and personal meditations. In this study, Bataille s multifaceted relationship to religion is interpreted as expressing a passion for radical otherness. Bataille is approached as a characteristically modern thinker who, nevertheless, questions some landmarks of modernity insofar as modernity is interpreted as a triumph of secularization. The dissertation is situated at the intersection of comparative religion and philosophy of religion. Methodologically, the study resorts to theoretical contextualization and concept analysis. Acknowledging that Bataille s writings challenge the assumptions about coherent meaning taken for granted in traditional philosophical analysis, the study also pays attention to the literary means and, in general, the performative level of Bataille s texts. The study constructs three theoretical contexts for Bataille s question of religion first of all, the interpretation of Hegel in the mid-20th century French philosophy. In the first section of the study, Bataille s uneasy relationship with Hegel as mediated by Alexandre Kojève is explored. The motivation of his question of radical otherness is argued to arise from his struggle with the Hegelian Kojèvean notion of negativity. The second context is the dialogue with the Christian mystical tradition. Starting from the analysis of two Bataillean notions, dramatization and contestation , it is argued that, firstly, Bataille s approach to radical otherness is analogous to certain procedures of mystical texts while, secondly, the function of otherness providing no firm foundation in Bataille s texts differs from its function in mystical texts. In the third section of the study, Bataille s quest for otherness is concretized by analyzing his views on otherness of other person, on violence, and on death themes that are brought together in Bataille s lasting interest in sacrifice. Bataille s understanding of sacrifice is proportioned to social scientific and philosophical discussions on sacrifice. It is argued that the commitment to the idea of sacrifice accounts for a partial failure in the Bataillean approach to otherness, the otherness of other person remaining its (at least half) blind spot. The study presents an overview of Bataille s thought on religion. It brings out Bataille s view of the paradoxical fundamental yet impossible role of otherness in the construction of human world, as well as his understanding of religious representations as both covering over and indicating this otherness. It describes Bataille s atheological mysticism as a peculiar modern form of religiosity, as an ambivalent mourning for and exaltation of fundamental loss.

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Tutkimuksessa analysoidaan kaaosteorian vaikutusta kaunokirjallisuudessa ja kirjallisuudentutkimuksessa ja esitetään, että kaaosteorian roolia kirjallisuuden kentällä voidaan parhaiten ymmärtää sen avaamien käsitteiden kautta. Suoran soveltamisen sijaan kaaosteorian avulla on käyty uudenlaisia keskusteluja vanhoista aiheista ja luonnontieteestä ammennetut käsitteet ovat johtaneet aiemmin tukkeutuneiden argumenttien avaamiseen uudesta näkökulmasta käsin. Väitöskirjassa keskitytään kolmeen osa-alueeseen: kaunokirjallisen teoksen rakenteen teoretisointiin, ihmisen (erityisesti tekijän) identiteetin hahmottamiseen ja kuvailemiseen sekä fiktion ja todellisuuden suhteen pohdintaan. Tutkimuksen tarkoituksena on osoittaa, kuinka kaaosteorian kautta näitä aiheita on lähestytty niin kirjallisuustieteessä kuin kaunokirjallisissa teoksissakin. Väitöskirjan keskiössä ovat romaanikirjailija John Barthin, dramatisti Tom Stoppardin ja runoilija Jorie Grahamin teosten analyysit. Nämä kirjailijat ammentavat kaaosteoriasta keinoja käsitteellistää rakenteita, jotka ovat yhtä aikaa dynaamisia prosesseja ja hahmotettavia muotoja. Kaunokirjallisina teemoina nousevat esiin myös ihmisen paradoksaalisesti tunnistettava ja aina muuttuva identiteetti sekä lopullista haltuunottoa pakeneva, mutta silti kiehtova ja tavoiteltava todellisuus. Näiden kirjailijoiden teosten analyysin sekä teoreettisen keskustelun kautta väitöskirjassa tuodaan esiin aiemmassa tutkimuksessa varjoon jäänyt, koherenssia, ymmärrettävyyttä ja realismia painottava humanistinen näkökulma kaaosteorian merkityksestä kirjallisuudessa.

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Perceiving students, science students especially, as mere consumers of facts and information belies the importance of a need to engage them with the principles underlying those facts and is counter-intuitive to the facilitation of knowledge and understanding. Traditional didactic lecture approaches need a re-think if student classroom engagement and active learning are to be valued over fact memorisation and fact recall. In our undergraduate biomedical science programs across Years 1, 2 and 3 in the Faculty of Health at QUT, we have developed an authentic learning model with an embedded suite of pedagogical strategies that foster classroom engagement and allow for active learning in the sub-discipline area of medical bacteriology. The suite of pedagogical tools we have developed have been designed to enable their translation, with appropriate fine-tuning, to most biomedical and allied health discipline teaching and learning contexts. Indeed, aspects of the pedagogy have been successfully translated to the nursing microbiology study stream at QUT. The aims underpinning the pedagogy are for our students to: (1) Connect scientific theory with scientific practice in a more direct and authentic way, (2) Construct factual knowledge and facilitate a deeper understanding, and (3) Develop and refine their higher order flexible thinking and problem solving skills, both semi-independently and independently. The mindset and role of the teaching staff is critical to this approach since for the strategy to be successful tertiary teachers need to abandon traditional instructional modalities based on one-way information delivery. Face-to-face classroom interactions between students and lecturer enable realisation of pedagogical aims (1), (2) and (3). The strategy we have adopted encourages teachers to view themselves more as expert guides in what is very much a student-focused process of scientific exploration and learning. Specific pedagogical strategies embedded in the authentic learning model we have developed include: (i) interactive lecture-tutorial hybrids or lectorials featuring teacher role-plays as well as class-level question-and-answer sessions, (ii) inclusion of “dry” laboratory activities during lectorials to prepare students for the wet laboratory to follow, (iii) real-world problem-solving exercises conducted during both lectorials and wet laboratory sessions, and (iv) designing class activities and formative assessments that probe a student’s higher order flexible thinking skills. Flexible thinking in this context encompasses analytical, critical, deductive, scientific and professional thinking modes. The strategic approach outlined above is designed to provide multiple opportunities for students to apply principles flexibly according to a given situation or context, to adapt methods of inquiry strategically, to go beyond mechanical application of formulaic approaches, and to as much as possible self-appraise their own thinking and problem solving. The pedagogical tools have been developed within both workplace (real world) and theoretical frameworks. The philosophical core of the pedagogy is a coherent pathway of teaching and learning which we, and many of our students, believe is more conducive to student engagement and active learning in the classroom. Qualitative and quantitative data derived from online and hardcopy evaluations, solicited and unsolicited student and graduate feedback, anecdotal evidence as well as peer review indicate that: (i) our students are engaging with the pedagogy, (ii) a constructivist, authentic-learning approach promotes active learning, and (iii) students are better prepared for workplace transition.

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The theme of this doctoral thesis is the Finnish printmaking in the years 1930-1939. During this decade, there were approximately 100 artists making prints in Finland. Indeed, the period was an especially important one for printmaking. Associations for printmakers were founded in Helsinki and Turku, training in the field was launched, and the number of printmaking exhibitions increased considerably. Through their national organisations, Finnish printmakers participated in many exhibitions abroad, interaction with Nordic printmakers being especially intense. Thus, a firm basis for post-war developments was created. However, printmakers' activity- which had continued throughout the 1930s - declined notably after the Winter War broke out in the autumn of 1939. As a result, the period 1930-1939 forms a coherent and distinct unity in Finnish printmaking history. The study consists of two parts: the main text and an appendix in which the production of each printmaking artist active in the 1930s is examined separately. The study also includes a comprehensive list of the prints made in the course of the decade. One of the central themes is the printmakers' relationship to "Finnish nationalist" art and concepts of art in the 1930s. I analyse the various manifestations of this way of thinking in the visual arts of the period. Finnish fine art in the period between the world wars has usually been characterised as conservative, introverted and spiritually isolated from the modern European trends of the time. On the basis of this study, such a view is too simple. Many artists and printmakers adopted a modernistic notion of art that approached the newest in European modernism, including such trends as avant-garde classicism and general European new Objective Realism (Die neue Sachlichkeit). On the other hand, choosing Finnish nationalist motifs did not necessarily mean that the artist was opposed to modernism: modernist artists could still be interested in national themes. The relationship of 1930s printmaking to the world of nationalist ideas is examined in this doctoral thesis from several perspectives. Towards the end of the main text, I examine the issue from the point of view of selected artists. Another feature that emerged during the study and turned out to be surprisingly widespread was the close relationship of many artists to religious, theosophical and pantheistic views. I deal with this issue in greater detail through a few representative printmakers.

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This paper reports on the fourth stage of an evolving study to develop a systems model for embedding education for sustainability (EfS) into pre-service teacher education. The fourth stage trialled the extension of the model to a comprehensive state-wide systems approach involving representatives from all eight Queensland teacher education institutions and other key policy agencies and professional associations. Support for trialling the model included regular meetings among the participating representatives and an implementation guide. This paper describes the first three stages of developing and trialling the model before presenting the case study and action research methods employed, four key lessons learned from the project, and the implications of the major outcomes for teacher education policies and practices. The Queensland-wide multi-site case study revealed processes and strategies that can enable institutional change agents to engage productively in building capacity for embedding EfS at the individual, institutional and state levels in pre-service teacher education. Collectively, the project components provide a system-wide framework that offers strategies, examples, insights and resources that can serve as a model for other states and/or territories wishing to implement EfS in a systematic and coherent fashion.

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The study shows that the reading paradigm derived from codes Roland Barthes presented in his S/Z exposes the postmodernic nature of Saul Bellow s Herzog (1964), and embodies in which way the novel is organized as a radical rewriting of modernism and its ideology. I explore how solid, compact and modernistic subject breaks down at every level of Herzog s narration. I actually argue that the heteroglossic novel is representative of an early American postmodern movement in literaure, and it should by no means be dissected narrowly as a realistic or naturalistic novel at all. The intertextual code verifies that the interpretation of Herzog remains inadequate if one doesn t take account of the novel s significant intertextual references to other texts. In fact, even the mind of Moses Herzog, the protagonist of the novel, is a mosaic of citations. It emerges from the dissertation that the figure of Don Quixote follows Moses Herzog as an ambiguous shadow while the professor of history struggles with his anxiety and anguish, and travels in a mentally confused state around the U.S. for five days in the early 1960s, encountering the impending atmosphere of transition as the country is on the threshold of a significant cultural and social change. There is a strong necessity for updated interpretation of Herzog partly because its centrality to Bellow s own career as a writer but mainly because it has been previously read trough modernistic lenses. I shall try to proof in my study that American Jewish Saul Bellow s (1915 2005) Herzog escapes any kind of simple, elemental or essentialistic construction or reading and in real terms it doesn t offer any comprehensive, total or coherent solution or system for those philosophical doctrines it criticizes and makes fun of. The philosophical, conceptual and cultural substance of Herzog does not constitute an independent or autonomous theoretical tract which would have a life of its own. Altough the novel reflects the continuity of Bellow s writing it is clearly some kind of conscious or unconscious experiment during his long career as a writer. He hasn t been so radical before or since the publication of Herzog. It is unarguably his most postmodern novel.The reading paradigm based on specific codes demonstrates how deep into the basic questions of his personal life and existence itself he must dive in oder to find his many ways towards authentic or primordial self in fragmented and shattered world which is constanly rewritten and which makes human being a tourist of his own life. In that ongoing process the protagonist has to accept the ultimate plurality of his mind and self. He must confront that the modernistic definition of identity as a solid, monolithic and stable entity has broken down into different, inconsistent and even contradictory possibilities of identification. Moses Herzog embodies obviously Stuart Hall s description of the postmodern self his identity has turn into a movable feast.

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The object of this study is Jacopo Bassano (c. 1510 1592) as a fresco painter and the significance of frescoes in his late production. The research focuses on the only surviving cycle of frescoes of his later years in the Cartigliano parish church, bearing the date 1575. The other cycle studied here was painted for the 16th century parish church of Enego. It contained one of the most extensive fresco decorations executed by Jacopo Bassano together with his eldest son Francesco. However, nothing has survived of the fresco cycle and the ceiling paintings of the church, nor is any visual documentation of them left. Only the small altarpiece attributed to Jacopo Bassano and depicting Saints Justine, Sebastian, Anthony Abbott, and Roch (dated to c. 1555/1560) has been preserved. I have suggested that the frescoes of the Cartigliano parish church should be examined in the interpretational context of the spirituality of the post-Tridentine period. This period frames the historical context for the frescoes and functions as a basis for the iconographical interpretation that I have proposed. I have shown that the iconographic programme of the frescoes in the choir of the Cartigliano parish church has obvious points of contact with the Catholic doctrines reconfirmed by the Council of Trent (1545 1563). I also argue that the fresco cycle and the ceiling paintings of the Enego church should be placed in the same interpretational context as the frescoes of Cartigliano. I present a reconstruction of the frescoes in the choir attributed to Jacopo Bassano and of those on the walls of the nave attributed to his son Francesco Bassano. According to my reconstruction, the frescoes in the choir and nave walls formed a coherent cycle with a unitary iconographic programme which included the 28 paintings with Old Testament subjects in the nave ceiling. The reconstruction includes the dating and the iconography of the fresco programme and its interpretative basis. The reconstruction is based on visitation records and inventories from the 16th and 17th centuries as well as on the oldest relevant literature, namely the descriptions offered by Carlo Ridolfi (1648) and G. B. Verci (1775). I also consider the relationship of the large compositional sketches attributed to Jacopo Bassano and depicting Christological subjects to the lost frescoes in Enego. These studies have been executed with coloured chalks, and many of them are also dated 1568 or 1569 by the painter. I suggest in this study that these large studies in coloured chalks were preparatory drawings for the fresco cycle in Enego, depicting scenes from the life and suffering of Christ. All the subjects of the aforesaid drawings were included in the Enego cycle.

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The study discusses the position of France as the United States’ ally in NATO in 1956-1958. The concrete position of France and the role that it was envisioned to have are being treated from the point of view of three participants of the Cold War: France, the United States and the Soviet Union. How did these different parties perceive the question and did these views change when the French Fourth Republic turned into the Fifth in 1958? The study is based on published French and American documents of Foreign Affairs. Because of problems with accessibility to the Soviet archival sources, the study uses reports on France-NATO relations of Pravda newspaper, the official organ of the Communist Party of the USSR, to provide information about how the Soviet side saw the question. Due to the nature and use of source material, and the chronological structure of the work, the study belongs methodologically to the research field of History of International Relations. As distinct from political scientists’ field of research, more prone to theorize, the study is characteristically a historical research, a work based on qualitative method and original sources that aims at creating a coherent narrative of the views expressed during the period covered by the study. France’s road to a full membership of NATO is being treated on the basis of research literature, after which discussions about France’s position in the Western Alliance are being chronologically traced for the period of last years of the Fourth Republic and the immediate months of coming back to power of Charles de Gaulle. Right from the spring of 1956 there can be seen aspirations of France, on one hand, to maintain her freedom of action inside the Western Alliance and, on the other, to widen the dialogue between the allies. The decision on France’s own nuclear deterrent was made already during the Fourth Republic, when it was thought to become part of NATO’s common defence. This was to change with de Gaulle. The USA felt that France still fancied herself as a great power and that she could not participate in full in NATO’s common defence because of her colonies. The Soviet Union saw the concrete position of France in the Alliance as in complete dependence on the USA, but her desired role was expressed largely in “Gaullist” terms. The expressions used by the General and the Soviet propaganda were close to each other, but the Soviet Union could not support de Gaulle without endangering the position of the French Communist Party. Between the Fourth and Fifth Republics no great rupture in content took place concerning the views of France’s role and position in the Western Alliance. The questions posed by de Gaulle had been expressed during the whole period of Fourth Republic’s existence. Instead, along with the General the weight and rhetoric of these questions saw a great change. Already in the early phase the Americans saw it possible that with de Gaulle, France would try to change her role. The rupture took place in the form of expression, rather than in its content.

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Proton magnetic resonance and spin-lattice relaxation studies have been carried out on (NH4)2CdI4 as a function of temperature (77–400 K) and Larmor frequency (10, 20 and 30 MHz). The T1 data indicate isotropic tumbling of ammonium ions at equivalent sites till 160 K. There is an indication of a phase transition at 265 K, the activation energy for molecular reorientation increases from 2.8 kcal/mole to 4.6 kcal/mole. The relaxation results and the linewidth data support the presence of two inequivalent sites at low temperatures, one having an environment corresponding to near-rigid-lattice limit and the other undergoing fast reorientations. The behaviour of the free induction decay with temperature below 120 K suggests a coherent motion for the faster species.

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The interpretation of irony in this study is seen as being crucially dependent on the notion of coherence. Coherence depends on a complex interplay of contextual features, which is why all interpretations must be seen as socio-cultural processes. An utterance is perceived as coherent if it makes sense and if it hangs together. Incoherent utterances can result in an ironic interpretation; however, the incoherence must also be perceived as being intentional, and intentionality in turn is a sign of the ironist's rejecting stance. The study does not encompass the notion of irony of fate nor situational irony that is unintentional. Irony is defined in this study as a combination of five components. It is seen as (1) a negative attitude that reflects (2) the intention of the ironist, and (3) has a target and most often (4) a victim too. Essential to irony is its fifth component, the fact that one or more of these four components must be inferred from co- or context. The componential definition of irony is crucial in deciding whether an interpretation is ironic or not, and the definition makes it possible to discern the differences as well as the similarities between different kinds of irony. The method of the study is experimental: 12 Finnish newspaper texts that could be considered to be ironic were interpreted by 107 informants. The interpretation of one of the texts was based on unelicited feedback given by readers of a weekly magazine. The responses were analyzed to determine (a) whether the texts were perceived as being coherent or incoherent and (b) whether the informants appealed to any of the five components of irony. The results of the analyses of the informants' responses indicate that differences between the ironic and non-ironic interpretations of the texts can be explained in terms of whether or not the informant regarded the text as being coherent. The thesis also discusses the shortcomings of other accounts of irony: the Gricean theory of conversational implicature, speech act theory, irony as rhetoric, irony as pretense, irony as echoic mention, and irony as framing. In contrast to these other accounts, the study focuses on irony as a textual phenomenon and underlines the importance of socio-cultural context in the interpretation of irony. Key words: irony, coherence, incoherence, the componential definition of irony, interpretation of linguistic utterances.