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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Per una storia della cerealicoltura in Italia settentrionale dal Neolitico all’Età del Ferro: strategie adattive e condizionamenti ambientali. / The history of the cereals cultivation in north Italy from neolithic to Bronze Age: adaptive strategies and environmental conditioning.

Carra, Marialetizia <1974> 04 July 2012 (has links)
Il presente elaborato si occupa della storia della cerealicoltura in un percorso diacronico dal Neolitico all’Età del Ferro. Sono presentate le analisi carpologiche di 14 siti archeologici dell’Italia settentrionale, esaminati secondo le più moderne tecniche di indagine archeobotanica. / The present study deals with the history of agriculture in a diachronic course from the Neolithic to the Iron Age. 14 studies of archaeological sites in northern Italy are presented, examined according to the most modern techniques of archaeobotanical investigation.
72

Reciproche influenze tra geomorfologia e popolamento antico presso le piane di foce dei fiumi tirrenici. Il caso del Fiume Garigliano / Environment and settlements near the Tyrrhenian river mouths. The Garigliano river

Ferrari, Kevin <1981> 04 July 2012 (has links)
La Piana di foce del Garigliano (al confine tra Lazio e Campania) è caratterizzata, fino ad epoche recenti, dalla presenza di aree palustri e umide. Lo studio in corso cerca di ricostruire l’evoluzione dell’ambiente costiero mettendolo in relazione alla presenza dell’uomo, alla gestione del territorio, alle vicende storiche e alle variazioni climatiche utilizzando molteplici metodologie tipiche della geoarcheologia. Si tratta di un approccio multidisciplinare che cerca di mettere insieme analisi tipiche dell’archeologia, della topografia antica, della geomorfologia, della geologia e della paleobotanica. Fino all’età del Ferro l’unica traccia di popolamento viene da Monte d’Argento, uno sperone roccioso isolato lungo la costa, posto al limite occidentale di un ambiente sottostante che sembra una palude chiusa e isolata da apporti sedimentari esterni. Con il passaggio all’età del ferro si verifica un mutamento ambientale con la fine della grande palude e la formazione di una piccola laguna parzialmente comunicante con il mare. L’arrivo dei romani alla fine del III secolo a.C. segna la scomparsa dei grandi centri degli Aurunci e la deduzione di tre colonie (Sessa Aurunca, Sinuessa, Minturno). Le attività di sistemazione territoriale non riguardarono però le aree umide costiere, che non vennero bonificate o utilizzate per scopi agricoli, ma mantennero la loro natura di piccoli laghi costieri. Quest’epoca è dunque caratterizzata da una diffusione capillare di insediamenti, basati su piccole fattorie o installazioni legate allo sfruttamento agricolo. Poche sono le aree archeologiche che hanno restituito materiali successivi al II-III secolo d.C. La città resta comunque abitata fino al VI-VII secolo, quando l’instabilità politica e l’impaludamento dovettero rendere la zona non troppo sicura favorendo uno spostamento verso le zone collinari. Un insediamento medievale è attestato solo a Monte d’Argento e una frequentazione saracena dell’inizio del IX secolo è riportata dalle fonti letterarie, ma non vi è ancora nessuna documentazione archeologica. / The Garigliano plain (between Lazio and Campania) is characterized still recent times by an alternation of swamps or wet zones and well drained areas due to the presence of old beach ridges. The settlement system and the economy of the region were influenced by these natural conditions. Toponyms, cartography and aerial photos show all the signs of these typical coastal facies. This research wants to reconstruct the evolution of the coastal landscape and to study the relationship between the human presence, the organization of the territory, the historical events and the climatic changes thanks to the geoarchaeological methodologies. Before the Iron Age there is only one settlement on the top of Monte D’Argento, that is a little rocky promontory near the coastline. At the foot of this little hill there was a big swamp attested by a level of peats that was changing into a little lagoon communicating with the sea. This change terminated with the beginning of the Iron Age and contemporary a new settlements system started. The Roman control of the region started at the end of IVth century b.C. with the deduction of 3 colonies (Sessa Aurunca, Sinuessa, Minturno), and the centuriation of the territory. In this period there is a great number of archaeological areas that shows a widely spread population. Minturnae was located on the top of the most ancient beach ridge, from where it was possible to control an important crossing point on the river. After the IInd-IIIrd century A.D. there are few zones with pottery or archaeological sites and we can infer that a crisis of the settlement system was in act. The town was inhabitated till the end of the VIth or the beginning of the VIIth century A.D., then the population moved to the nearest hills.
73

La ricostruzione dell'assetto topografico della VI regio augustea di Roma dal periodo repubblicano all'età tardoantica / The reconstruction of the topography of the Augustan regio VI of Rome from the republican period until the Late Antiquity

Bruzzesi, Marco <1977> 16 September 2013 (has links)
La VI regio augustea di Roma rappresenta uno dei settori urbani maggiormente investiti dalle modifiche radicali compiute dall’uomo nel processo di urbanizzazione della città che ne hanno modificato profondamente la situazione altimetrica e la conformazione originaria. Questi notevoli cambiamenti ebbero origine sin dall’età antica, ma si intensificarono profondamente soprattutto nel periodo rinascimentale quando a partire da Pio IV e soprattutto con Sisto V, attivo in tante altre zone della città, si svilupparono numerose opere di rinnovamento urbanistico che incisero notevolmente sul volto e sulle caratteristiche della zona in esame. A partire dal Rinascimento fino ad arrivare ai grandi scavi della fine del 1800 tutto il quartiere incominciò a “popolarsi” di numerosi edifici di grande mole che andarono ad intaccare completamente le vestigia del periodo antico: la costruzione del Palazzo del Quirinale e dei vari palazzi nobiliari ma soprattutto la costruzione dei numerosi ministeri e della prima stazione Termini alla fine dell’800 comportarono numerosi sventramenti senza la produzione di una adeguata documentazione delle indagini di scavo. Questa ricerca intende ricostruire, in un’ottica diacronica, la topografia di uno dei quartieri centrali della Roma antica attraverso l’analisi dei principali fenomeni che contraddistinguono l’evoluzione del tessuto urbano sia per quanto riguarda le strutture pubbliche che in particolar modo quelle private. Infatti, il dato principale che emerge da questa ricerca è che questa regio si configura, a partire già dal periodo tardo-repubblicano, come un quartiere a vocazione prevalentemente residenziale, abitato soprattutto dall’alta aristocrazia appartenente alle più alte cariche dello Stato romano; oltre a domus ed insulae, sul Quirinale, vennero costruiti lungo il corso di tutta l’età repubblicana alcuni tra i più antichi templi della città che con la loro mole occuparono parte dello spazio collinare fino all’età tardoantica, rappresentando così una macroscopica e costante presenza nell’ingombro dello spazio edificato. / The Augustan VI Regio of Rome is one of the most urban areas hit by man-made radical changes in the process of urbanization of the city that have fundamentally altered the situation altitude and the original conformation. These remarkable changes originated from the age old but deeply intensified especially during the Renaissance when starting Pius IV and above with Sixtus V, active in many other areas of the city, developed numerous works of urban renewal that they recorded significantly on face and on the characteristics of the area. Since the Renaissance up to the large-scale excavations in the late 1800s around the neighborhood began to "populate" to many buildings of great size that went to undermine completely the vestiges of the ancient period: the construction of the Palazzo del Quirinale and the various palaces but especially the construction of numerous ministries and the first station Termini to the 800 behaved numerous eventrations without the production of a proper documentation of investigations of excavation. This research aims to reconstruct, in a diachronic way, the topography of one of the central districts of ancient Rome through the analysis of the main phenomena that characterize the evolution of the urban fabric both in terms of public buildings especially private ones. In fact, the main result that emerges from this research is that regional configuring, starting as early as the late Republican period, as a vocation mainly residential district, inhabited mainly by the high aristocracy belonging to the highest offices of the Roman state; as well domus and insulae, on the Quirinal, were built along the course of the republican age some of the oldest temples of the city with their size of the space occupied hill until Late Antiquity, representing a macroscopic and constant presence overall size of the space center.
74

L(ocus) d(atos) d(ecreto) d(ecurionum): La concessione di spazi pubblici nelle comunita' cittadine dell'italia romana / L(ocus) d(atus) d(ecreto) d(ecurionum): the granting of public spaces in the urban communities of Roman Italy

Pistarino, Valentina Emanuela <1981> 23 May 2014 (has links)
La tesi riguarda la concessione di spazi di proprietà pubblica a privati, intesi come singole persone o enti, quali ad esempio i collegi, da parte delle autorità cittadine. Le fonti a disposizione per indagare tale pratica burocratica sono quasi totalmente di natura epigrafica, per lo più attestanti l’espressione locus datus decreto decurionum, variamente abbreviata, o formule similari. Questo aspetto della vita civica è stata cursoriamente oggetto di studio in diversi contributi, ma si tratta di articoli che circoscrivono il tema, analizzandolo in relazione a ristrette aree geografiche, oppure considerandone determinati aspetti (ad esempio l’ambito sacro o quello funerario). Si è perciò ritenuto utile proseguire questa linea di ricerca affrontando uno studio di più ampio raggio, che comprenda la documentazione epigrafica dell’intero territorio italico (costituito dalle undici regioni augustee ad esclusione di Roma), per tutte le tipologie testuali (iscrizioni sacre, funerarie, onorarie, su opera pubblica, exempla decreti), allo scopo di formulare osservazioni più precise e puntuali sulla procedura burocratica in esame, pur con tutti i limiti noti a chi affronti questo genere di indagine. Tra le conclusioni raggiunte, è emerso come durante il I-II sec. d.C. vi fosse la tendenza a concedere, sporadicamente, dei loca sepulturae extraurbani a membri delle famiglie delle élites cittadine, anche donne e fanciulli, mentre il foro e le altre aree pubbliche interne alla città erano soprattutto utilizzate direttamente dai decurioni per l’elevazione di dediche e statue. Nel corso del II sec. d.C., con massima diffusione nell’età antonina e poi in quella severiana, prese invece piede l’uso privato a scopo onorario degli spazi pubblici siti all’interno delle città, ovvero in aree prima pressoché precluse all’intervento di singoli cittadini: familiari e liberti, collegi e altri organismi commissionavano statue dedicate prevalentemente agli amministratori locali, magistrati cittadini spesso divenuti anche cavalieri. / The thesis deals with the granting of public spaces to privates, defined as individuals or entities, such as colleges, by the city authorities. The sources available to investigate this bureaucratic practice are almost entirely the epigraphic ones, mostly showing the expression locus datus decreto decurionum, variously abbreviated, or similar formulas. This aspect of civic life has been sporadically studied in a number of contributions, but these are items that surround the topic, analyzing it in relation to restricted geographical areas, or considering certain aspects (such as the funerary or sacred sphere). It was therefore considered useful to continue this line of research tackling a study of more wide-ranging, including the epigraphic documentation of the entire Italian territory (consisting of the eleven Augustan regions with the exception of Rome), for all types of texts (sacred, funerary, honorary, on public works, exempla decreti) in order to express observations on the bureaucratic procedure in question, even with all the limits known to those who deal with this kind of investigation. Among the conclusions, it emerged that during the I-II century A.D. there was a tendency to sporadically grant loca sepulturae to the families’ members of the urban élites, including women and children, while the forum and other public areas inside the cities were directly used by the decuriones for the elevation of dedications and statues. During the second century AD, with maximum diffusion in the Antonine and Severan age, the private use of public spaces within the city for honorary aims increased, using areas previously almost precluded to the intervention of individual citizens: families and freedmen, colleges and other organizations commissioned statues mainly dedicated to local administrators, often also become equites.
75

GPS interference mitigation for small UAV applications.

Li, Joy January 2008 (has links)
The vulnerability of GPS to interference has been a major concern for both military and civilian applications, including small UAVs. Various signal processing techniques have been developed to improve the reliability of GPS receivers against different types of interference. Among these techniques, null steering is recognized as an effective method to protect GPS against both narrowband and broadband interference. However, due to the requirement of multiple antenna channels, it has mainly been implemented for large platform applications. This thesis examines the suitability of null steering techniques for small UAV applications and determines the practically achievable anti-jamming ability by implementing a two-element miniaturized adaptive antenna array. The adaptive antenna array is tested against a 2MHz broadband jamming signal under both laboratory testing conditions and a real jamming environment. Approximately 40dB anti-jamming range was achieved in the laboratory testing conditions. 38dB and 42dB were obtained in a real jamming environment with different antenna configuration. The likely performance limitations and possible further performance enhancements are also outlined in this thesis. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1363608 / Thesis (M.Eng.Sc.) - University of Adelaide, School of Electrical and Electronic Engineering, 2008
76

Dinâmica populacional, forrageamento e exposição de operárias de Ectatomma opaciventre (Hymenoptera : Formicidae) a iscas formicidas contendo sulfluramida, fipronil e clorpirifós

Tofolo, Viviane Cristina [UNESP] 20 January 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-01-20Bitstream added on 2014-06-13T19:25:15Z : No. of bitstreams: 1 tofolo_vc_dr_rcla_prot.pdf: 19466486 bytes, checksum: bad26d57e8eb11a239b119205310d9c6 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Ectatomma opaciventre (Hymenoptera: Formicidae: Ectatomminae) apresenta características morfológicas e comportamentais plesiomórficas, como a presença de um ferrão funcional, monoginia, colônias pequenas e estratégia de forrageamento solitário. Vive tanto nos ambientes preservados quanto nos alterados pelo homem, como os agroecossistemas, estando constantemente em contato com os produtos destinados ao controle de formigas consideradas pragas, como as cortadeiras do gênero Atta. Pouco se conhece a respeito de sua biologia básica (como dieta, rotas de forrageamento, distribuição espacial dos ninhos, composição dos hidrocarbonetos cuticulares) e das conseqüências advindas de seu contato com as iscas formicidas usadas para o controle de formigas cortadeiras em pastagens. Dessa forma, foi determinado por meio do “Método do Vizinho Mais Próximo” o padrão de distribuição espacial de seus ninhos em uma área degradada de 1800m2 na cidade de Rio Claro/SP/Brasil. Como na maioria das espécies de formigas tropicais, os ninhos de E. opaciventre apresentaram distribuição espacial do tipo regular ou hiperdispersa, com densidade de 0,018 ninho/m2. A distância média encontrada para o vizinho mais próximo foi de 5,57m, variando de 1,93m a 12,96m. Em vista da dificuldade em encontrar a rainha desta espécie, foi utilizado o método da “Espectroscopia Fotoacústica no Infravermelho com Transformada de Fourier (FTIR)” para identificar os hidrocarbonetos cuticulares da única rainha encontrada e das operárias de 9 ninhos satélites. Também foi determinado o grau de similaridade entre elas. Com os resultados obtidos ficou evidenciada a condição polidômica nessa espécie devido à semelhança entre o perfil químico cuticular da rainha e das operárias de ninhos vizinhos. Além disso... / Ectatomma opaciventre belongs to the subfamily Ectatomminae, which presents morphological and behavioral characteristics typical of more basal groups, such as the presence of a functional sting, monogyny, small colonies, and individual foraging strategies while searching for food. This species lives both in preserved and modified environments, such as agroecosystems, and it is constantly in contact with products intended to control ants regarded as pests, such as leaf-cutting ants of the genus Atta. The patterns of spatial distribution of nests over a 1800m2 degraded area in the city of Rio Claro, SP, Brazil were determined using a nearest neighbor method. As in most tropical species, the nests of E. opaciventre presented a regular or hyperdispersed spatial distribution, with a density of 0.018 nests/m2. The average nearest neighbor distance was 5.57 m, ranging from 1.93 m to 12.96 m. Considering the difficulty in finding queens of this species, the Fourier Transform-Infrared Photoacoustic Spectroscopy (FTIR-PAS) was used to identify cuticular hydrocarbons of the only queen found and of workers from nine satellite nests. The degree of similarity between them was also determined. From the results, polydomy was evident in this species because of the similarity between the cuticular chemical profile of the queen and that of workers from neighboring nests. Moreover, it was observed that the colonies that were not collected disappeared one year after the removal of the queen from the study area. In another area in the city of Rio Claro, of 4,800 m2, the diet of this species was studied by identifying the prey collected during the period of highest foraging activity. Besides, the foraging routes of three nests were determined by following foragers during their excursions in the field. The maximum foraging distance was... (Complete abstract click electronic access below)
77

Caracterização de populações genéticas de Solenopsis invicta através de marcadores moleculares microssatélites. Correlação de similaridade entre populações hospedeiras e endossimbiose /

Souza, Rodrigo Fernando de. January 2011 (has links)
Orientador: Odair Correa Bueno / Banca: Maria Santina de Castro Morini / Banca: Ricardo Harakava / Resumo: As formigas da espécie Solenopsis invicta são nativas da América do Sul, mas elas foram introduzidas em novos ambientes e passaram a causar sérios danos à agricultura e pecuária bem como causar alguns transtornos ao ser humano. Muitos estudos sobre a biologia reprodutiva de S. invicta foram conduzidos com populações introduzidas; porém, poucos com as populações nativas. As ferramentas moleculares como microssatélties e mtDNA podem auxiliar na investigação sobre a biologia reprodutiva das espécies. Diferentes comportamentos sociais de S. invicta como a monoginia e a poliginia, podem interferir na biologia reprodutiva da espécie, e a utilização das ferramentas moleculares corretas pode evidenciar este comportamento. A expansão das populações nativas, assim como a introdução dessa formiga em outros ambientes, pode ter levado à interação com outros táxons de formigas e com outros tipos de organismos. Essa interação pode ter sido responsável pela aquisição da endobactéria Wolbachia. Ela é uma bactéria intracelular que pode causar distúrbios reprodutivos em seus hospedeiros. Este trabalho analisou 10 ninhos de S. invicta coletados em cinco cidades do Estado de São Paulo com o objetivo de inferir sobre a biologia reprodutiva de S. invicta, utilizando marcadores moleculares microssatélites e mtDNA e também verificar a presença de Wolbachia. A formação de quatro grupos filogeneticamente distintos para mtDNA sugerem linhagens divergentes de haplótipos dentro dos dez ninhos. Essa separação também pode indicar interferências na dispersão natural das fêmeas. A análise dos microssatélites revelou que alguns problemas moleculares podem interferir na investigação sobre a biologia reprodutiva. A análise específica de poliginia indica que todos os ninhos analisados são monogínicos, mas os resultados de microssatélites sugerem que ninhos de S. invicta ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The ants of Solenopsis invicta are native of South America, but they were introduced into new environments and began to cause serious damage to agriculture and livestock and cause some inconvenience to humans. Many studies on the reproductive biology of S. invicta were conducted with introduced populations, but few with the native populations. The molecular tools such as analysis of mtDNA and microsatellites can assist in research on the reproductive biology of the species.Different social behavior of S. invicta as monogyny and polygyny, can interfere in the reproductive biology of the species, and the use of the correct molecular tools may show this behavior.The expansion of the native populations, as well as the introduction of this ant in other environments may have led to the interaction with other taxa of ants and other types of organism. This interaction may have been responsible for the acquisition of endobacteria Wolbachia. This bacteria is intracellular and can cause reproductive disorders in their hosts. This study analyzed 10 nests of S. invicta collected in five cities of São Paulo aiming to infer the reproductive biology of S. invicta, using microsatellite markers and mtDNA and also verify the presence of Wolbachia. The formation of four groups phylogenetically distinct mtDNA suggests divergent lineages of haplotypes inside the ten nests. This separation can also indicate interference with the natural dispersal of females. Analysis of microsatellite revealed that some molecular problems may interfere in the research on the reproductive biology. The specific analysis of polygyny indicates that all nests that were analyzed are monogynous, but results of microsatellite suggest that nests of S. invicta have more than one reproductive queen. The Wolbachia presence analysis revealed two strains, the A from subgroup InvA of the S. invicta and the B strain characteristic of ... (Complete abstract click electronic access below) / Mestre
78

The social biology of the slave-making ant Harpagoxenus sublaevis

Bourke, Andrew January 1987 (has links)
No description available.
79

Heuristic approaches for crane scheduling in ship building

Wen, Charlie Hsiao Kuang 09 August 2008 (has links)
This study provides heuristic approaches, including an ant colony optimization (ACO) inspired heuristic, to solve a crane scheduling problem that exists in most shipyards, where cranes are a primary means of processing and handling materials. Cranes move on a network of tracks, thus, blocking of crane movements is an issue. The crane scheduling problem consists of two major sub-problems: scheduling problem that determines the best overall order in which jobs are to be performed; the assignment problem that assigns cranes to jobs. The proposed heuristic consists of an Earliest Due Date sorting procedure in combination with an ACO assignment procedure that aims to satisfy the objectives of minimizing makespan while maximizing crane utilization. Test data sets of various sizes are generated and the results of the proposed approach are compared to other developed heuristics. The proposed approach outperforms others in both objective measures and obtains solutions in a timely manner.
80

Population-Based Ant Colony Optimization for Multivariate Microaggregation

Askut, Ann Ahu 01 January 2013 (has links)
Numerous organizations collect and distribute non-aggregate personal data for a variety of different purposes, including demographic and public health research. In these situations, the data distributor is responsible with the protection of the anonymity and personal information of individuals. Microaggregation is one of the most commonly used statistical disclosure control methods. In microaggregation, the set of original records is first partitioned into several groups. The records in the same group are similar to each other. The minimum number of records in each group is k. Each record is replaced by the mean value of the group (centroid). The confidentiality of records is protected by ensuring that each group has at least a minimum of k records and each record is indistinguishable from at least k-1 other records in the microaggregated dataset. The goal of this process is to keep the within-group homogeneity higher and the information loss lower, where information loss is the sum squared deviation between the actual records and the group centroids. Several heuristics have been proposed for the NP-hard minimum information loss microaggregation problem. Among the most promising methods is the multivariate Hansen-Mukherjee (MHM) algorithm that uses a shortest path algorithm to identify the best partition consistent with a specified ordering of records. Developing improved heuristics for ordering multivariate points for microaggregation remains an open research challenge. This dissertation adapts a version of the population-based ant colony optimization algorithm (PACO) to order records within which MHM algorithm is used iteratively to improve the quality of grouping. Results of computational experiments using benchmark test problems indicate that P-ACO/MHM based microaggregation algorithm yields comparable or improved information loss than those obtained by extant methods.

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