25 resultados para Hard part
em Helda - Digital Repository of University of Helsinki
Resumo:
Hard Custom, Hard Dance: Social Organisation, (Un)Differentiation and Notions of Power in a Tabiteuean Community, Southern Kiribati is an ethnographic study of a village community. This work analyses social organisation on the island of Tabiteuea in the Micronesian state of Kiribati, examining the intertwining of hierarchical and egalitarian traits, meanwhile bringing a new perspective to scholarly discussions of social differentiation by introducing the concept of undifferentiation to describe non-hierarchical social forms and practices. Particular attention is paid to local ideas concerning symbolic power, abstractly understood as the potency for social reproduction, but also examined in one of its forms; authority understood as the right to speak. The workings of social differentiation and undifferentiation in the village are specifically studied in two contexts connected by local notions of power: the meetinghouse institution (te maneaba) and traditional dancing (te mwaie). This dissertation is based on 11 months of anthropological fieldwork in 1999‒2000 in Kiribati and Fiji, with an emphasis on participant observation and the collection of oral tradition (narratives and songs). The questions are approached through three distinct but interrelated topics: (i) A key narrative of the community ‒ the story of an ancestor without descendants ‒ is presented and discussed, along with other narratives. (ii) The Kiribati meetinghouse institution, te maneaba, is considered in terms of oral tradition as well as present-day practices and customs. (iii) Kiribati dancing (te mwaie) is examined through a discussion of competing dance groups, followed by an extended case study of four dance events. In the course of this work the community of close to four hundred inhabitants is depicted as constructed primarily of clans and households, but also of churches, work co-operatives and dance groups, but also as a significant and valued social unit in itself, and a part of the wider island district. In these partly cross-cutting and overlapping social matrices, people are alternatingly organised by the distinct values and logic of differentiation and undifferentiation. At different levels of social integration and in different modes of social and discursive practice, there are heightened moments of differentiation, followed by active undifferentiation. The central notions concerning power and authority to emerge are, firstly, that in order to be valued and utilised, power needs to be controlled. Secondly, power is not allowed to centralize in the hands of one person or group for any long period of time. Thirdly, out of the permanent reach of people, power/authority is always, on the one hand, left outside the factual community and, on the other, vested in community, the social whole. Several forms of differentiation and undifferentiation emerge, but these appear to be systematically related. Social differentiation building on typically Austronesian complementary differences (such as male:female, elder:younger, autochtonous:allotochtonous) is valued, even if eventually restricted, whereas differentiation based on non-complementary differences (such as monetary wealth or level of education) is generally resisted, and/or is subsumed by the complementary distinctions. The concomitant forms of undifferentiation are likewise hierarchically organised. On the level of the society as a whole, undifferentiation means circumscribing and ultimately withholding social hierarchy. Potential hierarchy is both based on a combination of valued complementary differences between social groups and individuals, but also limited by virtue of the undoing of these differences; for example, in the dissolution of seniority (elder-younger) and gender (male-female) into sameness. Like the suspension of hierarchy, undifferentiation as transformation requires the recognition of pre-existing difference and does not mean devaluing the difference. This form of undifferentiation is ultimately encompassed by the first one, as the processes of the differentiation, whether transformed or not, are always halted. Finally, undifferentiation can mean the prevention of non-complementary differences between social groups or individuals. This form of undifferentiation, like the differentiation it works on, takes place on a lower level of societal ideology, as both the differences and their prevention are always encompassed by the complementary differences and their undoing. It is concluded that Southern Kiribati society be seen as a combination of a severely limited and decentralised hierarchy (differentiation) and of a tightly conditional and contextual (intra-category) equality (undifferentiation), and that it is distinctly characterised by an enduring tension between these contradicting social forms and cultural notions. With reference to the local notion of hardness used to characterise custom on this particular island as well as dance in general, it is argued in this work that in this Tabiteuean community some forms of differentiation are valued though strictly delimited or even undone, whereas other forms of differentiation are a perceived as a threat to community, necessitating pre-emptive imposition of undifferentiation. Power, though sought after and displayed - particularly in dancing - must always remain controlled.
Resumo:
Coordination and juxtaposed sentences The object of this study is the examination of the relations between juxtaposed clauses in contemporary French. The matter in question is sentences which are composed of several clauses adjoined without a conjunction or other connector, as in: Je détournai les yeux, mon c ur se mit à battre. The aim of the study is to determine, which quality is the relation in these sentences and, on the other hand, what is the part of the coordination there. Furthermore, what is this relation of coordination, which, according to some grammars, manifests through a conjunction of coordination, but which, according to some others is marked in juxtaposed sentences through different features. The study is based on a corpus of written French from literary and journalistic text sources. Syntactic, semantic and textual properties in the clauses are discussed. The analysis points to differences so, it has been noted, in each case, if one of the clauses is affirmative and the other negative and if in the second clause, the subject has not been repeated. Also, an analysis has been made on the ground of the tense, mode, phrase structure type, and thematic structure, taking into account, in each case, if the clauses are identical or different. Punctuation has been one of the properties considered. The final aim has been to eliminate gradually, based on the partition of properties, subordinate sentences, so that only the hard core of coordinate sentences remains. In this way, the coordination could be defined similarly as the phoneme is defined as a group of distinctive features. The quantitative analyses have led to the conclusion that the sentences which, from a semantic point of view, are interpreted as coordinating, contain the least of these differences, while the sentences which can be considered as subordinating present the most of these differences. The conditions of coordination are, in that sense, hierarchical, so that the syntactic constraints have to make room for semantic, textual and cognitive factors. It is interesting to notice that everyone has the ability to produce correct coordinating structures and recognize incorrect coordinating structures. This can be explained by the human ability to categorize which has been widely researched in the semantic of prototype. The study suggests that coordination and subordination could be considered as prototypical cognitive categories based on different linguistic and pragmatic features.
Resumo:
The present study provides a usage-based account of how three grammatical structures, declarative content clauses, interrogative content clause and as-predicative constructions, are used in academic research articles. These structures may be used in both knowledge claims and citations, and they often express evaluative meanings. Using the methodology of quantitative corpus linguistics, I investigate how the culture of the academic discipline influences the way in which these constructions are used in research articles. The study compares the rates of occurrence of these grammatical structures and investigates their co-occurrence patterns in articles representing four different disciplines (medicine, physics, law, and literary criticism). The analysis is based on a purpose-built 2-million-word corpus, which has been part-of-speech tagged. The analysis demonstrates that the use of these grammatical structures varies between disciplines, and further shows that the differences observed in the corpus data are linked with differences in the nature of knowledge and the patterns of enquiry. The constructions in focus tend to be more frequently used in the soft disciplines, law and literary criticism, where their co-occurrence patterns are also more varied. This reflects both the greater variety of topics discussed in these disciplines, and the higher frequency of references to statements made by other researchers. Knowledge-building in the soft fields normally requires a careful contextualisation of the arguments, giving rise to statements reporting earlier research employing the constructions in focus. In contrast, knowledgebuilding in the hard fields is typically a cumulative process, based on agreed-upon methods of analysis. This characteristic is reflected in the structure and contents of research reports, which offer fewer opportunities for using these constructions.
Resumo:
A Sibyl fallen into everyday life. The enfolding of the identity of modern woman in Marja- Liisa Vartio s novel Kaikki naiset näkevät unia ( All Women Have Dreams ). --- Marja-Liisa Vartio played a remarkable part in renewing Finnish literature. My thesis examines her novel Kaikki naiset näkevät unia (1960), which describes the life of a middle-aged housewife, Mrs. Pyy ( Mrs. Hazel Hen ). She has moved from country to city and lives now in a suburb, in the Helsinki of the 1950 s. In Finnish literature, the novel is the first significant description of a modern city woman accomplished by modernistic means. My research examines the identity of a woman in the Finland of the 50 s, an epoch marked by the inevitable transition into modernity. My aim is to look into the ways in which the female identity enfolds in Kaikki naiset näkevät unia, how it takes its form, how it is described and commented. The primary method is contextual close reading; the novel is seen in the social, cultural and historical context of the time it was published. Essential elements in this study are literary motifs and images in the novel, and particularly transtextual relations as defined by Gérald Genette. The focus is on hypertextuality, intertextuality and paratextuality. Kaikki naiset näkevät unia emerges as a modern version of Madame Bovary by Gustave Flaubert. A woman s life spent in illusive dreaming is transferred from a 1900th century bourgeois town in France to a middle class Finnish suburb in the 1950 s. Vartio s novel is a variant of an ancient Finnish ballad I, a bird without a nest , making it into a modern narration of transition. The inner, mental journey from country to city is of great length, and the liminal life in a suburb does not make the passage any easier. Like the lyrical voices in the poetry of Edith Södergran, also Mrs. Pyy finds it hard to discover any values of sisterhood or those of ideal femininity in modern times. In earlier studies of Marja-Liisa Vartio s prose, stress has been laid on the discourse of her narrators and characters, as well as on its modern literary form. In this research, however, urgent allusions to paintings, old and new, are taken into account, since Mrs. Pyy mirrors herself against art, both classical and modern. Principal images in this context are Michelangelo s Sibyls in the ceiling of the Sistine Chapel, and a modern painting, which remains unidentified. Mrs. Pyy turns out to be a tragicomic character, who has magnanimous illusions about herself, but is compelled to accept the fact the she is only a mediocre person. She is nothing more than a first generation city dweller; she is not a modern, aloof outsider but a mere dilettante, who desperately tries to live out modern city life. Kaikki naiset näkevät unia is a striking picture of the 1950 s, a picture that is construed in the consciousness of Mrs. Pyy. We are shown everyday life growing more and more modern after the war and woman s role growing more and more subject to increasing pressure for change.
Resumo:
This study analyses British military planning and actions during the Suez Crisis in 1956. It seeks to find military reasons for the change of concepts during the planning and compares these reasons with the tactical doctrines of the time. The thesis takes extensive advantage of military documents preserved in the National Archives, London. In order to expand the understanding of the exchange of views during the planning process, the private papers of high ranking military officials have also been consulted. French military documents preserved in the Service Historique de la Defence, Paris, have provided an important point of comparison. The Suez Crisis caught the British armed forces in the middle of a transition phase. The main objective of the armed forces was to establish a credible deterrence against the Soviet Union. However, due to overseas commitments the Middle East playing a paramount role because of its economic importance the armed forces were compelled to also prepare for Limited War and the Cold War. The armed forces were not fully prepared to meet this demand. The Middle Eastern garrison was being re-organised after the withdrawal from the Canal Base and the concept for a strategic reserve was unimplemented. The tactical doctrines of the time were based on experiences from the Second World War. As a result, the British view of amphibious operations and the subsequent campaigns emphasised careful planning, mastery of the sea and the air, sufficient superiority in numbers and firepower, centralised command and extensive administrative preparations. The British military had realized that Nasser could nationalise the Suez Canal and prepared an outline plan to meet this contingency. Although the plan was nothing more than a concept, it was accepted as a basis for further planning when the Canal was nationalised at the end of July. This plan was short-lived. The nominated Task Force Commanders shifted the landing site from Port Said to Alexandria because it enabled faster expansion of the bridgehead. In addition, further operations towards Cairo the hub of Nasser s power would be easier to conduct. The operational concept can be described as being traditional and was in accordance with the amphibious warfare doctrine. This plan was completely changed at the beginning of September. Apparently, General Charles Keightley, the Commander-in-Chief, and the Chairman of the Chiefs of Staff Committee developed the idea of prolonged aerial operations. The essence of the concept was to break the Egyptian will to resist by attacking the oil facilities, the transportation system and the armed forces. This victory through air concept would be supported by carefully planned psychological operations. This concept was in accordance with the Royal Air Force doctrine, which promoted a bomber offensive against selected target categories. General Keightley s plan was accepted despite suspicions at every planning level. The Joint Planning Staff and the Task Force Commanders opposed the concept from the beginning to the end because of its unpredictability. There was no information that suggested the bombing would persuade the Egyptians to submit. This problem was worsened by the fact that British intelligence was unable to provide reliable strategic information. The Task Force Commanders, who were responsible for the tactical plans, were not able to change Keightley s mind, but the concept was expanded to include a traditional amphibious assault on Port Said due to their resistance. The bombing campaign was never tested as the Royal Air Force was denied authorisation to destroy the transportation and oil targets. The Chiefs of Staff and General Keightley were too slow to realise that the execution of the plan depended on the determination of the Prime Minister. However, poor health, a lack of American and domestic support and the indecisiveness of the military had ruined Eden s resolve. In the end, a very traditional amphibious assault, which was bound to succeed at the tactical level but fail at the strategic level, was launched against Port Said.
Resumo:
This dissertation consists of four articles and an introduction. The five parts address the same topic, nonverbal predication in Erzya, from different perspectives. The work is at the same time linguistic typology and Uralic studies. The findings based on a large corpus of empirical Erzya data, which was collected using several different methods and included recordings of the spoken language, made it possible for the present study to apply, then test and finally discuss the previous theories based on cross-linguistic data. Erzya makes use of multiple predication patterns which vary from totally analytic to the morphologically very complex. Nonverbal predicate clause types are classified on the basis of propositional acts in clauses denoting class-membership, identity, property and location. The predicates of these clauses are nouns, adjectives and locational expressions, respectively. The following three predication strategies in Erzya nonverbal predication can be identified: i. the zero-copula construction, ii. the predicative suffix construction and iii. the copula construction. It has been suggested that verbs and nouns cannot be clearly distinguished on morphological grounds when functioning as predicates in Erzya. This study shows that even though predicativity must not be considered a sufficient tool for defining parts of speech in any language, the Erzya lexical classes of adjective, noun and verb can be distinguished from each other also in predicate position. The relative frequency and degree of obligation for using the predicative suffix construction decreases when moving left to right on the scale verb adjective/locative noun ( identificational statement). The predicative suffix is the main pattern in the present tense over the whole domain of nonverbal predication in Standard Erzya, but if it is replaced it is most likely to be with a zero-copula construction in a nominal predication. This study exploits the theory of (a)symmetry for the first time in order to describe verbal vs. nonverbal predication. It is shown that the asymmetry of paradigms and constructions differentiates the lexical classes. Asymmetrical structures are motivated by functional level asymmetry. Variation in predication as such adds to the complexity of the grammar. When symmetric structures are employed, the functional complexity of grammar decreases, even though morphological complexity increases. The genre affects the employment of predication strategies in Erzya. There are differences in the relative frequency of the patterns, and some patterns are totally lacking from some of the data. The clearest difference is that the past tense predicative suffix construction occurs relatively frequently in Standard Erzya, while it occurs infrequently in the other data. Also, the predicative suffixes of the present tense are used more regularly in written Standard Erzya than in any other genre. The genre also affects the incidence of the translative in uľ(ń)ems copula constructions. In translations from Russian to Erzya the translative case is employed relatively frequently in comparison to other data. This study reveals differences between the two Mordvinic languages Erzya and Moksha. The predicative suffixes (bound person markers) of the present tense are used more regularly in Moksha in all kinds of nonverbal predicate clauses compared to Erzya. It should further be observed that identificational statements are encoded with a predicative suffix in Moksha, but seldom in Erzya. Erzya clauses are more frequently encoded using zero-constructions, displaying agreement in number only.
Resumo:
As a Novice Teacher at Comprehensive School: The authentic experiences of the beginning teachers during their first year of teaching The aim of this study is to explicate the novice year of teaching in the light of teachers´ authentic experiences. The subject of this investigation is the teachers´ subjective world of experience during their first academic year of teaching and the sharing of these experiences in collaborative consulting meetings. The themes discussed in the meetings were introduced into the collaborative group by the novice teachers themselves, and the progress of discussion was con-trolled by them. The research data was gathered in a consultative working group where the way a novice teacher starts to interpret, analyze and identify his/her own complex and dynamic teaching situations was observed. The research data gathered in this way illuminates novice teachers´ world of experience and mental picture as well as the unconscious sides of school life. In a theoretical frame of reference, the work of a teacher is identified, according to systemic scientific thought, as a dynamic triangle in which the basic elements are the personality of the teacher, the role of the teacher and the school as an organization. These basic elements form a whole within which the teacher works. The dynamics of this triangle in a teacher’s work are brought to light through the study of the phenomena of groups and group dynamics since a teacher works either as a member of a group (working community), as a leader of a group (teaching situations) or in a network (parent – teacher cooperation). Therefore, tension and force are always present in teaching work. The main research problem was to explain how a novice teacher experiences his/her first working year as a teacher. The participants (n=5) were teaching at five different comprehensive schools in the city of Helsinki. This was their first long-term post as a teacher. The research data consists of seven collaborative consulting meetings, as well as recordings and transcripts of the meetings. A classificatory framework was developed for data analysis which enabled a sys-tematic qualitative content analysis based on theory and material. In addition to the consulting meetings, the teachers were interviewed at the beginning and at the end of the process of collecting the research material. The interviews were used to interpret the meanings of the content analysis based on raw data. The findings show that there is a gap between teacher education and the reality of school life, which causes difficulties for a novice teacher during his/her first teaching year. The gap is rather a global educational problem than a national one, and therefore it is independent of cultural factors. Novice teachers desire a well-structured theory of teacher education and a clear programme where the themes and content delve deeper and deeper into the subject matter during the study years. According to the novice teachers, teacher education frequently consists of sporadic and unconnected study and class situations. An individual content weakness of teacher education is the lack of insufficient initiation into evaluation processes. The novice teachers suggest that a student must be provided good-quality and competent guidance during the study years and during his or her induction. There should be a well-organized, structured and systematic induction program for novice teachers. The induction program should be overseen by an organization so that the requirements of a qualified induction can be met. The findings show that the novice teachers find the first year of teaching at comprehensive school emotionally loaded. The teachers experienced teaching as difficult work and found the workload heavy. Nevertheless, they enjoyed their job because, as they said, there were more pleasant than unpleasant things in their school day. Their main feeling at school was the joy of success in teaching. The novice teachers felt satisfaction with their pupils. The teachers experienced the more serious feelings of anger and disgust when serious violence took place. The most difficult situations arose from teaching pupils who had mental health problems. The toughest thing in the teacher´s work was teaching groups that are too heterogeneous. The most awkward problems in group dynamics happened when new immigrants, who spoke only their own languages, were integrated into the groups in the middle of the school year. Teachers wanted to help children who needed special help with learning but restated at the same time that the groups being taught shouldn’t be too heterogeneous. The teachers wished for help from school assistants so that they could personally concentrate more on teaching. Not all the parents took care of their children according to the comprehensive school law. The teachers found it hard to build a confidential relationship between home and school. In this study, novice teachers found it hard to join the teaching staff at school. Some of the teachers on staff were very strong and impulsive, reacting loudly and emotionally. These teachers provoked disagreement, conflicts, power struggles and competition among the other teachers. Although the novice teachers of the study were all qualified teachers, three of them were not interested in a permanent teaching job. For these teachers teaching at a primary school was just a project, a short period in their working life. They will remain in the teaching profession as long as they are learning new things and enjoying their teaching job. This study is an independent part of the research project on Interplay – Connecting Academic Teacher Education and Work, undertaken by the Department of Applied Sciences of Education at the University of Helsinki. Key words: novice teacher, emotions, groups and group dynamics, authority, co-operation between home and school, teacher community, leadership at school, induction, consulting
Resumo:
The development of many embryonic organs is regulated by reciprocal and sequential epithelial-mesenchymal interactions. These interactions are mediated by conserved signaling pathways that are reiteratively used. Cleidocranial dysplasia (CCD) is a congenital syndrome where both bone and tooth development is affected. The syndrome is characterized by short stature, abnormal clavicles, general bone dysplasia, and supernumerary teeth. CCD is caused by mutations in RUNX2, a transcription factor that is a key regulator of osteoblast differentiation and bone formation. The first aim of this study was to analyse the expression of a family of key signal molecules, Bone morphogenetic protein (Bmp) at different stages of tooth development. Bmps have a variety of functions and they were originally discovered as signals inducing ectopic bone formation. We performed a comparative in situ hybridisation analysis of the mRNA expression of Bmp2-7 from initiation of tooth development to differentiation of dental hard tissues. The expression patterns indicated that the Bmps signal between the epithelial and mesenchymal tissues during initiation and morphogenesis of tooth development, as well as during the differentiation of odontoblasts and ameloblasts. Furthermore, they are also part of the signalling networks whereby the enamel knot regulates the patterning of tooth cusps. The second aim was to study the role of Runx2 during tooth development and thereby to gain better understanding of the pathogenesis of the tooth phenotype in CCD. We analysed the tooth phenotype of Runx2 knockout mice and examined the patterns and regulation of Runx2 gene expression.. The teeth of wild-type and Runx2 mutant mice were compared by several methods including in situ hybridisation, tissue culture, bead implantation experiments, and epithelial-mesenchymal recombination studies. Phenotypic analysis of Runx2 -/- mutant tooth development showed that teeth failed to advance beyond the bud stage. Runx2 expression was restricted to dental mesenchyme between the bud and early bell stages of tooth development and it was regulated by epithelial signals, in particular Fgfs. We searched for downstream targets of Runx2 by comparative in situ hybridisation analysis. The expression of Fgf3 was downregulated in the mesenchyme of Runx2 -/- teeth. Shh expression was absent from the enamel knot in the lower molars of Runx2 -/- and reduced in the upper molars. In conclusion, these studies showed that Runx2 regulates key epithelial-mesenchymal interactions that control advancing tooth morphogenesis and histodifferentiation of the epithelial enamel organ. In addition, in the upper molars of Runx2 mutants extra buddings occured at the palatal side of the tooth bud. We suggest that Runx2 acts as an inhibitor of successional tooth formation by preventing advancing development of the buds. Accordingly, we propose that RUNX2 haploinsuffiency in humans causes incomplete inhibition of successional tooth formation and as a result supernumerary teeth.
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In Finland one of the most important current issues in the environmental management is the quality of surface waters. The increasing social importance of lakes and water systems has generated wide-ranging interest in lake restoration and management, concerning especially lakes suffering from eutrophication, but also from other environmental impacts. Most of the factors deteriorating the water quality in Finnish lakes are connected to human activities. Especially since the 1940's, the intensified farming practices and conduction of sewage waters from scattered settlements, cottages and industry have affected the lakes, which simultaneously have developed in to recreational areas for a growing number of people. Therefore, this study was focused on small lakes, which are human impacted, located close to settlement areas and have a significant value for local population. The aim of this thesis was to obtain information from lake sediment records for on-going lake restoration activities and to prove that a well planned, properly focused lake sediment study is an essential part of the work related to evaluation, target consideration and restoration of Finnish lakes. Altogether 11 lakes were studied. The study of Lake Kaljasjärvi was related to the gradual eutrophication of the lake. In lakes Ormajärvi, Suolijärvi, Lehee, Pyhäjärvi and Iso-Roine the main focus was on sediment mapping, as well as on the long term changes of the sedimentation, which were compared to Lake Pääjärvi. In Lake Hormajärvi the role of different kind of sedimentation environments in the eutrophication development of the lake's two basins were compared. Lake Orijärvi has not been eutrophied, but the ore exploitation and related acid main drainage from the catchment area have influenced the lake drastically and the changes caused by metal load were investigated. The twin lakes Etujärvi and Takajärvi are slightly eutrophied, but also suffer problems associated with the erosion of the substantial peat accumulations covering the fringe areas of the lakes. These peat accumulations are related to Holocene water level changes, which were investigated. The methods used were chosen case-specifically for each lake. In general, acoustic soundings of the lakes, detailed description of the nature of the sediment and determinations of the physical properties of the sediment, such as water content, loss on ignition and magnetic susceptibility were used, as was grain size analysis. A wide set of chemical analyses was also used. Diatom and chrysophycean cyst analyses were applied, and the diatom inferred total phosphorus content was reconstructed. The results of these studies prove, that the ideal lake sediment study, as a part of a lake management project, should be two-phased. In the first phase, thoroughgoing mapping of sedimentation patterns should be carried out by soundings and adequate corings. The actual sampling, based on the preliminary results, must include at least one long core from the main sedimentation basin for the determining the natural background state of the lake. The recent, artificially impacted development of the lake can then be determined by short-core and surface sediment studies. The sampling must be focused on the basis of the sediment mapping again, and it should represent all different sedimentation environments and bottom dynamic zones, considering the inlets and outlets, as well as the effects of possible point loaders of the lake. In practice, the budget of the lake management projects of is usually limited and only the most essential work and analyses can be carried out. The set of chemical and biological analyses and dating methods must therefore been thoroughly considered and adapted to the specific management problem. The results show also, that information obtained from a properly performed sediment study enhances the planning of the restoration, makes possible to define the target of the remediation activities and improves the cost-efficiency of the project.
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The analysis of sequential data is required in many diverse areas such as telecommunications, stock market analysis, and bioinformatics. A basic problem related to the analysis of sequential data is the sequence segmentation problem. A sequence segmentation is a partition of the sequence into a number of non-overlapping segments that cover all data points, such that each segment is as homogeneous as possible. This problem can be solved optimally using a standard dynamic programming algorithm. In the first part of the thesis, we present a new approximation algorithm for the sequence segmentation problem. This algorithm has smaller running time than the optimal dynamic programming algorithm, while it has bounded approximation ratio. The basic idea is to divide the input sequence into subsequences, solve the problem optimally in each subsequence, and then appropriately combine the solutions to the subproblems into one final solution. In the second part of the thesis, we study alternative segmentation models that are devised to better fit the data. More specifically, we focus on clustered segmentations and segmentations with rearrangements. While in the standard segmentation of a multidimensional sequence all dimensions share the same segment boundaries, in a clustered segmentation the multidimensional sequence is segmented in such a way that dimensions are allowed to form clusters. Each cluster of dimensions is then segmented separately. We formally define the problem of clustered segmentations and we experimentally show that segmenting sequences using this segmentation model, leads to solutions with smaller error for the same model cost. Segmentation with rearrangements is a novel variation to the segmentation problem: in addition to partitioning the sequence we also seek to apply a limited amount of reordering, so that the overall representation error is minimized. We formulate the problem of segmentation with rearrangements and we show that it is an NP-hard problem to solve or even to approximate. We devise effective algorithms for the proposed problem, combining ideas from dynamic programming and outlier detection algorithms in sequences. In the final part of the thesis, we discuss the problem of aggregating results of segmentation algorithms on the same set of data points. In this case, we are interested in producing a partitioning of the data that agrees as much as possible with the input partitions. We show that this problem can be solved optimally in polynomial time using dynamic programming. Furthermore, we show that not all data points are candidates for segment boundaries in the optimal solution.
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At the Tevatron, the total p_bar-p cross-section has been measured by CDF at 546 GeV and 1.8 TeV, and by E710/E811 at 1.8 TeV. The two results at 1.8 TeV disagree by 2.6 standard deviations, introducing big uncertainties into extrapolations to higher energies. At the LHC, the TOTEM collaboration is preparing to resolve the ambiguity by measuring the total p-p cross-section with a precision of about 1 %. Like at the Tevatron experiments, the luminosity-independent method based on the Optical Theorem will be used. The Tevatron experiments have also performed a vast range of studies about soft and hard diffractive events, partly with antiproton tagging by Roman Pots, partly with rapidity gap tagging. At the LHC, the combined CMS/TOTEM experiments will carry out their diffractive programme with an unprecedented rapidity coverage and Roman Pot spectrometers on both sides of the interaction point. The physics menu comprises detailed studies of soft diffractive differential cross-sections, diffractive structure functions, rapidity gap survival and exclusive central production by Double Pomeron Exchange.