• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 12
  • 8
  • 4
  • 3
  • 3
  • 2
  • 2
  • Tagged with
  • 38
  • 5
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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.
1

Design and Implementation of Anti-Spam Service over a SIP User Agent

Shih, Jhih-Wei 29 July 2008 (has links)
With the popularity of the VoIP, the method of communication is gradually changing from email to internet telephony. The email communication is always being used for advertising and phishing. Also, this junk information may be used for internet telephony and may disturb users while the internet telephony becomes more and more popular. SPIT (Spam for Internet Telephony)may become a serious problem in the network. Moreover, the influence cause by internet telephony maybe more serious than email. Hence, this paper wants to provide a SIP terminal that can filter the caller. With limited resources, the filter uses white and black lists and integrated with back-end SPIT database to design an efficient SPIT filter. Through this filter, we can block the spam call efficiently and keep the quality of the VoIP service.
2

The spring 1976 erosion of Siletz Spit, Oregon, with an analysis of the causative wave and tide conditions

McKinney, Barbara Ann 20 September 1976 (has links)
During the period 1970-76, Siletz Spit on the mid-Oregon coast has suffered foredune erosion. This erosion is associated with high wave conditions along the coast, produced by intense storms in the North Pacific. During the winter of 1972-73 and during January through March 1976 the erosion was particularly severe. The pre-1975 erosion of the spit has been documented in a previous study. One of the main purposes of the present study is to document the 1976 erosion and to contrast it with the earlier episodes. It differed principally in that a small wash-over of the spit occurred in one area and beach drift logs were thrown up onto the dunes. Neither occurred during previous erosion episodes, even during the 25 December 1972 storm when wave breakers exceeded a significant wave height of 7 meters. This is because the 1972 storm occurred at a time of low water level, neap tide conditions. In contrast, the 18 February 1976 major storm occurred during spring tide conditions, causing the wash-over and log throwing, even though the waves were smaller than in December 1972. The amount of dune retreat was somewhat less in 1976 than in 1972-73, partly because of the shorter time period over which the 1976 erosion occurred and partly because of the use of protective riprap. The large waves causing the erosion at Siletz Spit are generated by storms in the North Pacific. The storm systems for December 1972, January 1973, and February 1976 were analyzed as to fetch distances, wind speeds and directions, movements of the fetches, and other factors important in the generation of waves. Waves hindcasted from these data were compared with measurements of the waves obtained from a seismometer system at the Marine Science Center in Newport, Oregon. This comparison demonstrated that these distant fetches were responsible for the waves causing erosion on Siletz Spit. Waves generated locally by coastal winds appear to be of negligible importance in the erosion. This is also shown by a comparison between the wave measurements and data on the coastal winds at Newport during the times of maximum erosion. Tides were investigated for their role in contributing to coastal erosion. High spring tides allow the storm waves to better reach the dunes or sea cliffs and so permit greater erosion. Neap tides, with their lower water levels, diminish the amount of erosion. Many of the differences in the December 1972 and February 1976 erosion episodes were due to the difference in tide levels. Storm surges were determined for Yaquina Bay, Oregon, by subtracting the predicted high-tide levels from the observed levels. It was concluded that significant storm surges did not occur at the times of maximum spit erosion and therefore did not contribute to the erosion processes. / Graduation date: 1977
3

The Erosion of Siletz Spit, Oregon

Rea, Campbell Cary 13 December 1974 (has links)
Siletz Bay is a drowned river valley filled with Holocene alluvial and estuarine sediments and is separated from the ocean by a sand spit 3.8 km in length. Since the area was settled by white man in the 1890's, the bay has apparently experienced rapid siltation, due to increased farming and logging. This along with the damming of the Siletz River sloughs has altered circulation patterns in the bay. Deflection of the Siletz River flow by the prograding Drift Creek delta has caused 105 m of erosion since 1912 on the east side of Siletz Spit. The ocean side of the spit suffers periodic erosional episodes separated by periods of accretion and dune building. The most recent and publicized erosion occurred during the winter of 1972-73 when it was feared that the spit might be breached; one partially constructed house was lost and three others were saved only by timely riprapping. A sand mining operation may have aggravated the recent erosion by disrupting the sand budget, the balance of sand additions and losses from the beach. All of the foredune on the spit has been stabilized by dune grass and much of it has been riprapped. The long term effects of stabilization and riprapping are uncertain. / Graduation date: 1975
4

Sympathetic Landscapes: an aesthetics for the Leslie Street Spit

Chan, Alexander January 2013 (has links)
The Leslie Street Spit is a five kilometre rubble breakwater on the eastern waterfront of Toronto. Built during the mid-twentieth-century as an infrastructural add-on to the existing Port Lands Industrial District, the artificial peninsula was a lakefilling project made to realize the city???s ambitious desire for economic prosperity and world-class prestige by expanding its existing harbour facilities. With the decline of Toronto???s shipping industry, the Leslie Spit remained an active dump site for urban clean fill until it was unexpectedly colonized by flora and fauna during the 1970s. The site is now recognized as an important local and international environmental resource. Visitors to the Leslie Spit experience a diverse landscape of ecosystems and industrial rubble helded by the city as a symbol of environmental revival within a former industrial region undergoing another phase of urbanization. While the local aesthetic experience of the headland is pleasurable and aligns with the reinvention of Toronto as am environmentally conscious and sustainable city, human visitors remain psychologically and physically removed from the inhabiting non-human life. Occasionally, the desire to conserve and preserve the natural world requires a separation between humans and non-humans. This relationship is carried out in varying degrees on the Leslie Spit. This thesis documents events at the headland where the human/non-human divide is rigidly enforced or left ambiguous. The purpose of the thesis is not to treat the headland as an eccentric spectacle, but to investigate the unexpected coexistence between humans and non-humans.
5

An ecological study of the lizard fauna of Kaitorete Spit, Canterbury : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Applied Science, Lincoln University /

Freeman, A. B. January 1994 (has links)
Thesis (M. Appl. Sc.)--Lincoln University, 1994.
6

O uso de captchas de áudio no combate ao spam em telefonia IP

Tiago Tavares Madeira, Frederico 31 January 2011 (has links)
Made available in DSpace on 2014-06-12T16:00:10Z (GMT). No. of bitstreams: 2 arquivo6087_1.pdf: 1872863 bytes, checksum: 5421c048c3358bc43e4f5ae9a04428fc (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Spam é o termo usado para referir-se aos e-mails não solicitados, que geralmente são enviados para um grande número de pessoas, e é hoje considerado um dos maiores problemas enfrentados na Internet. Com o aumento da disponibilização de banda larga, popularização de tecnologias de internet e o aumento da utilização e disponibilização de soluções baseadas em VoIP (Voice over IP), é esperado que um problema semelhante passe a afetar esta nova área. Esta ameaça é conhecida por SPIT (SPAM over Internet Telephony) e é definida como geração automatizada de chamadas não solicitadas utilizando como transporte o IP através do VoIP ao invés das tradicionais linhas telefônicas. O potencial do SPIT em reduzir a produtividade é muito maior do que a do SPAM, porque no SPIT a utilização de tempo de uma pessoa já é contabilizada a partir do momento em que o telefone começa a tocar. Podemos acrescentar que o SPIT não consiste apenas no incômodo a um usuário, quando aplicado contra uma rede, pois pode consumir seus recursos dificultando ou ainda inviabilizar a utilização dos recursos da rede. As características do SPIT são diferentes do SPAM, portanto não podemos aplicar as mesmas técnicas usadas no SPAM em ataques do tipo SPIT. Propomos neste trabalho uma ferramenta para identificar e proteger uma rede VoIP contra ataques de SPIT. Como visto em outros tipos de ameaças a redes de dados, a utilização de um único método não é suficiente para garantir a proteção e identificação dos ataques. Portanto, na nossa abordagem, a ferramenta desenvolvida faz uso de Testes Reversos de Turing formatados em um CAPTCHA no formato de uma mensagem de áudio, com o objetivo de identificar se a chamada é ou não um SPIT. Essa técnica é aplicada em conjunto com outras técnicas descritas ao longo do texto. Desta forma, é composta uma ferramenta de prevenção e identificação com a finalidade de garantir uma melhor proteção contra ataques de SPIT, em redes baseadas em VoIP
7

Study on the change of coastal topography-A case study of Fu-Long coast

Liu, Chia-Cheng 20 July 2011 (has links)
The reasons to cause the variation of the Fu-Long resort area have been investigated in the study. The resort area is the spit extended from the northern coast of the Shung-si River located at the northeast part of Taiwan. Historical coastlines and the bathymetry surveyed in the last 15 years have been used to interpret the cause of the coastline variation. Numerical simulation of the wave and flow field is performed to assist the interpretation. It is found that the spit may be eroded during typhoon season by the flood from Shung-si River and recovered in the next year if the typhoon occurred in monsoon season in which the eroded sediment carried by northward monsoon waves will be merged to the coastline by the following southward northeast season waves. On the contrary, if the typhoon occurred during northeast wind season, the accompanying southward will carry the eroded sediment further south and the spit may not recover in the next year. It is further found that the source of the sediment from the river has been decreased in the last decade and the coastline retreated in responding the source decrease. Man-made fishery port close to the spit also deposited some sediment and may cause the variation of the coastline.
8

Kuršių nerijos nacionalinio parko vabalai (Coleoptera): sistema, fauna ir ekologija / Beetles (Coleoptera) of Curonian Spit National park: taxonomy, fauna and ecology

Ferenca, Romas 07 June 2005 (has links)
The results of faunistical and ecological research on beetles (Coleoptera) of Curonian Spit were presented in this work. A species composition of different habitats: Baltic sea coastal area and the foredune ridge,wooded dunes, humid dune slacks, white and grey dunes and Curonian lagoons was established on the basis of research. The greatest species diversity was established in humid dune slacks (234 species), the lowest species diversity was established eudominant, dominant, subdominant and accessory species in the four Curonian Spit habitats: wooded dunes, humid dune slacks, grey dunes and littoral Curonian lagoons. The distribution and diversity of rare and protected insects species in Curonian Spit were established. There were found 10 species of beetles new for Lithuanian fauna:Elaphropus parvulus, Pterostichus ovoideus (Carabidae), Enochrus bicolor (Hydrophilidae), Lomechusa emarginata, Quedius infuscatus (Staphylinidae), Negastrius arenicola, Cardiophorus asellus (Elateridae), Obrium brunneum (Cerambycidae), Dicranthus elegans, Glocianus moelleri (Curculionidae). The beetles of 4 species: Cicindela maritima, Calosoma inquisitor (Carabidae), Polyphylla fullo (Scarabeidae), Stenagostus rufus (Elateridae)wee included in Red Data book of Lithuania and the beetles of 11 species - in List of Key forest habitats species.
9

GRAIN SIZE ANALYSIS OF THE SEDIMENTS OF SPURN HEAD, EAST YORKSHIRE, ENGLAND

NICHOLAS, JAMES ROBERT 17 April 2003 (has links)
No description available.
10

Selling feminism : a study of contemporary feminist literatures, communities, and markets

Hurt, Erin Allison 08 October 2010 (has links)
This dissertation explores how recent feminist authors uses their literature to create, sustain, and expand the feminist movement through their creation of communities and readerships. This project consists of four case studies, each of which examines how a feminist author represents feminist identity, where she locates herself in relation to the mainstream marketplace, which strategies she uses to circulate her representation, and what forms of small and large feminist communities she is able to create. To develop this analysis of feminist literary public culture, I focus on playwright Eve Ensler and her work with the V-Day movement, novelist Alisa Valdes-Rodriguez and her expansion of the chick lit genre, poet Lorna Dee Cervantes and her online small press, and the members of spoken word group Sister Spit and their traveling road show. These individual case studies, taken as a whole, speak to the ways that feminist authors are engaging mainstream and feminist readers in ways that create and energize feminist communities. / text

Page generated in 0.0188 seconds