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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.
11

CORRELAÇÃO DE ALERTAS EM UM INTERNET EARLY WARNING SYSTEM / ALERT CORRELATION IN AN INTERNET EARLY WARNING SYSTEM

Ceolin Junior, Tarcisio 28 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Intrusion Detection Systems (IDS) are designed to monitor the computer network infrastructure against possible attacks by generating security alerts. With the increase of components connected to computer networks, traditional IDS are not capable of effectively detecting malicious attacks. This occurs either by the distributed amount of data that traverses the network or the complexity of the attacks launched against the network. Therefore, the design of Internet Early Warning Systems (IEWS) enables the early detection of threats in the network, possibly avoiding eventual damages to the network resources. The IEWS works as a sink that collects alerts from different sources (for example, from different IDS), centralizing and correlating information in order to provide a holistic view of the network. This way, the current dissertation describes an IEWS architecture for correlating alerts from (geographically) spread out IDS using the Case-Based Reasoning (CBR) technique together with IP Georeferencing. The results obtained during experiments, which were executed over the implementation of the developed technique, showed the viability of the technique in reducing false-positives. This demonstrates the applicability of the proposal as the basis for developing advanced techniques inside the extended IEWS architecture. / Sistemas de Detecção de Instrução (Intrusion Detection Systems IDS) são projetados para monitorar possíveis ataques à infraestruturas da rede através da geração de alertas. Com a crescente quantidade de componentes conectados na rede, os IDS tradicionais não estão sendo suficientes para a efetiva detecção de ataques maliciosos, tanto pelo volume de dados como pela crescente complexidade de novos ataques. Nesse sentido, a construção de uma arquitetura Internet Early Warning Systems (IEWS) possibilita detectar precocemente as ameaças, antes de causar algum perigo para os recursos da rede. O IEWS funciona como um coletor de diferentes geradores de alertas, possivelmente IDS, centralizando e correlacionado informações afim de gerar uma visão holística da rede. Sendo assim, o trabalho tem como objetivo descrever uma arquitetura IEWS para a correlação de alertas gerados por IDS dispersos geograficamente utilizando a técnica Case-Based Reasoning (CBR) em conjunto com Georreferenciamento de endereços IP. Os resultados obtidos nos experimentos, realizados sobre a implementação da técnica desenvolvida, mostraram a viabilidade da técnica na redução de alertas classificados como falsos-positivos. Isso demonstra a aplicabilidade da proposta como base para o desenvolvimento de técnicas mais apuradas de detecção dentro da arquitetura de IEWS estendida.
12

Development of streamflow forecasting model using artificial neural network in the Awash River Basin, Ethiopia

Edossa, D.C., Babel, M.S. January 2011 (has links)
Published Article / Early indication of possible drought can help in developing suitable drought mitigation strategies and measures in advance. Therefore, drought forecasting plays an important role in the planning and management of water resource in such circumstances. In this study, a non-linear streamflow forecasting model was developed using Artificial Neural Network (ANN) modeling technique at the Melka Sedi stream gauging station, Ethiopia, with adequate lead times. The available data was divided into two independent sets using a split sampling tool of the neural network software. The first data set was used for training and the second data set, which is normally about one fourth of the total available data, was used for testing the model. A one year data was set aside for validating the ANN model. The streamflow predicted using the model on weekly time step compared favorably with the measured streamflow data (R2 = 75%) during the validation period. Application of the model in assessing appropriate agricultural water management strategies for a large-scale irrigation scheme in the Awash River Basin, Ethiopia, has already been considered for publication in a referred journal.
13

Previsão hidrometeorológica visando sistema de alerta antecipado de cheias em bacias urbanas / Hidrometeorological precipitation forecast for flood early warning systems in urban areas

Andrade, Juliana Pontes Machado de 13 September 2006 (has links)
Freqüentemente, a população das áreas metropolitanas é surpreendida pela ocorrência de inundações muito rápidas que causam danos diversos. O sistema de alerta antecipado contra inundações é uma ferramenta que visa minimizar tais impactos. O componente de previsão do sistema será abordado neste trabalho. Tal previsão é feita através de um modelo conceitual de previsão hidrometeorológica de precipitação baseado em equações termodinâmicas e modelo simplificado de física das nuvens seguido de um modelo chuva-vazão. A antecedência proporcionada pelo modelo hidrometeorológico aplicado é de 30 minutos para variáveis de entrada observadas. Este tempo pode ser estendido com a inclusão de estimativas futuras das variáveis de entrada. A calibração do modelo foi feita manualmente com o uso de duas medidas de desempenho, esta etapa pode ser aprimorada em pesquisas futuras. Apesar da simplicidade do modelo hidrometeorológico apresentou-se satisfatório em algumas simulações, conseguindo prever o início das precipitações. / Urban population are often surprised by flash floods which cause several kinds of damages. An early warning system is a tool which aims to minimize such impacts. This work will approach the forecast component of this system. A conceptual hydrometeorological precipitation forecasting model, based on thermodynamics equations and simplified cloud physics, will be used to perform the forecast. Model lead time is 30 minutes for measured inputs, this time can be extended by the use of estimated inputs instead of the measured ones. Calibration was performed manually based on conservation of precipitation volume and its distribution in time. This step can be improved on future researches. In spite of model’s simplicity, some simulations presented satisfactory results, being able to forecast precipitation’s beginning.
14

Vad motiverar parlamenten? : En studie om vad som påverkar nationella parlament att utfärda motiverade yttranden i EU:s subsidiaritetsgranskning

Malvet Rydell, Fabian January 2019 (has links)
The study aims to empirically study the Early warning system and how national parliaments in the EU vary regarding the issuing of reasoned opinions. In recent years the subject of subsidiarity within the EU has become an increasingly debated and controversial topic. The Early warning system aims to alleviate the democratic deficiency of the EU, but the scientific community is divided on how efficient it is. Using data from the European parliament this study examines reasoned opinions and factors that influences why national parliaments issue them and why there is such a variation amongst the national parliaments issuing them. The study finds that being a member of the Eurozone and the EU15 has important implications for parliaments issuing reasoned opinions.
15

A Complete Model for Displacement Monitoring Based on Undifferenced GPS Observations

Andersson, Johan Vium January 2008 (has links)
During recent years there has been a great focus on the climate changes within the media. More or less every day more newspaper articles are presented about the global warming issue and the effect on us human race. Climate models predict higher temperatures and more rain in the northern part of Europe. It is also predicted that the weather will become more extreme e.g. it will rain a lot during longer periods than has been the norm. If these predictions are correct, the amount of water that is going to be transported away in streams and rivers will increase and so also will the subsoil water level. The latter increases the risk for landslides in areas with fine grained soils. An early warning system that is able to alert people before a landslide take place would be of great interest. The purpose of this work is to develop a complete real-time displacement monitoring system based on observations from several GPS-receivers that could be used as an early warning system. Due to the complex correlation structure of the traditionally used double differences, an alternative method based on undifferenced observations is used. Theoretically this approach shows some advantages and simplifies the correlative structure of observables compared to the double differenced method. A complete model for the undifferenced approach is presented in this thesis including its software implementation. A displacement detection system includes not only the positioning algorithms, but also methods to detect if any displacement occurs. There are many methods available to discriminate displacements, which are used in the traditional control of manufacturing processes. Several of these methods are compared in this thesis, such as the Shewhart chart, different Weighted Moving Average (WMA) charts and the CUmulative SUMmation (CUSUM). Practical tests show that it is possible to detect an abrupt shift on sub centimetre level at the same epoch as the shift occurs. Smaller shifts are also detectable with the applied approach but with a slightly longer detection time. / QC 20100624
16

Varningssystem för översvämningar orsakade av vårflöden och kraftig nederbörd / Flood Warning Systems for flooding caused by spring flood and heavy precipitation

Larsson, Martin January 2011 (has links)
Översvämningar förekommer regelbundet på stora delar av jordklotet. Utgående från de klimatförändringar vi ser idag med, bland annat, kraftigare och intensivare nederbörd är det troligt att det blir fler och större översvämningar framöver. Områden som inte tidigare varit översvämmade kan komma att bli översvämmande.   Varje land eller område med regelbundna översvämningar har någon form av varningssystem. Översikter över olika typer av system för att varna för översvämningar är svåra att finna.   Syftet med denna uppsats är att: Undersöka viktiga principer för effektiva varningssystem för översvämningar som orsakas av kraftig nederbörd och/eller vårflöden. Skapa en systematisk och strukturerad sammanställning över nuvarande system för att varna för översvämningar orsakade av kraftig nederbörd och/eller vårflöden. Ge praktiska exempel på några svenska kommuners system för att varna för översvämningar.   Litteratur- och internetsökningar kring varningssystem för översvämningar samt intervjuer med ”översvämningsansvariga” i Ödeshög och Vetlanda kommuner utgör grunden för informationen i denna uppsats.   Exempel på olika typer av varningssystem för översvämningar presenteras. Saker att tänka på vid val av, och vid drift och underhåll av, automatiska varningssystem belyses.   En indelning (Grust, 2006) av varningssystem i manuella, enkla automatiska och sofistikerade automatiska utökas till en matris med i matrisens andra dimension lokala, avrinningsområdes, nationella, multinationella och globala varningssystem. De i uppsatsen beskrivna exemplen på varningssystem positioneras in i matrisen.   Varningssystem för översvämningar i två svenska kommuner, Ödeshög och Vetlanda, beskrivs och likheter och skillnader mellan kommunernas system presenteras. / Flooding occurs all over the world on a regular basis. Based on the climate change ongoing today with heavier and more intense precipitation we can expect more and larger floods than we have seen before. Areas which have not been flooded earlier may now become flooded.   Every country or area which is flooded on a regular basis has some kind of warning system. Overviews of various types of flood warning systems are difficult to find.   The purpose of this thesis is to: Investigate important principles of effective flood warning systems caused by heavy precipitation and/or spring flood. Create a structured and systematical overview of current flood warning system for floods caused by heavy precipitation and/or spring flood. Describe two local Swedish community´s flood warning systems.   Literature and Internet search covering flood warning systems combined with interviews on site at Ödeshög and Vetlanda forms the basis for the information in this thesis.   Examples of various types of flood warning systems are presented. Issues regarding the selection of, and the operation and maintenance of, automatic warning systems are described.   A grouping (Grust, 2006) of warning systems in manual, simple automatic and sophisticated automatic is expanded to a matrix with the second dimension of the matrix being local, drainage area, national, multinational and global warning systems. The examples of warning systems covered in this thesis are placed in the matrix.   The similarities and differences between the flood warning systems in two local Swedish communities Ödeshög and Vetlanda are described.
17

Centralized control of space the use of space forces by a joint force commander /

Kelly, Ricky B. January 1900 (has links)
Thesis--School of Advanced Airpower Studies, Maxwell Air Force Base, Ala., 1992-93. / Title from title screen (viewed Oct. 28, 2003). "28 June 1993." Includes bibliographical references.
18

Real-Time Social Network Data Mining For Predicting The Path For A Disaster

Jain, Saloni 09 May 2015 (has links)
Traditional communication channels like news channels are not able to provide spontaneous information about disasters unlike social networks namely, Twitter. The present research work proposes a framework by mining real-time disaster data from Twitter to predict the path a disaster like a tornado will take. The users of Twitter act as the sensors which provide useful information about the disaster by posting first-hand experience, warnings or location of a disaster. The steps involved in the framework are – data collection, data preprocessing, geo-locating the tweets, data filtering and extrapolation of the disaster curve for prediction of susceptible locations. The framework is validated by analyzing the past events. This framework has the potential to be developed into a full-fledged system to predict and warn people about disasters. The warnings can be sent to news channels or broadcasted for pro-active action.
19

Previsão hidrometeorológica visando sistema de alerta antecipado de cheias em bacias urbanas / Hidrometeorological precipitation forecast for flood early warning systems in urban areas

Juliana Pontes Machado de Andrade 13 September 2006 (has links)
Freqüentemente, a população das áreas metropolitanas é surpreendida pela ocorrência de inundações muito rápidas que causam danos diversos. O sistema de alerta antecipado contra inundações é uma ferramenta que visa minimizar tais impactos. O componente de previsão do sistema será abordado neste trabalho. Tal previsão é feita através de um modelo conceitual de previsão hidrometeorológica de precipitação baseado em equações termodinâmicas e modelo simplificado de física das nuvens seguido de um modelo chuva-vazão. A antecedência proporcionada pelo modelo hidrometeorológico aplicado é de 30 minutos para variáveis de entrada observadas. Este tempo pode ser estendido com a inclusão de estimativas futuras das variáveis de entrada. A calibração do modelo foi feita manualmente com o uso de duas medidas de desempenho, esta etapa pode ser aprimorada em pesquisas futuras. Apesar da simplicidade do modelo hidrometeorológico apresentou-se satisfatório em algumas simulações, conseguindo prever o início das precipitações. / Urban population are often surprised by flash floods which cause several kinds of damages. An early warning system is a tool which aims to minimize such impacts. This work will approach the forecast component of this system. A conceptual hydrometeorological precipitation forecasting model, based on thermodynamics equations and simplified cloud physics, will be used to perform the forecast. Model lead time is 30 minutes for measured inputs, this time can be extended by the use of estimated inputs instead of the measured ones. Calibration was performed manually based on conservation of precipitation volume and its distribution in time. This step can be improved on future researches. In spite of model’s simplicity, some simulations presented satisfactory results, being able to forecast precipitation’s beginning.
20

Predictors of financial crises-do we see the same pattern in Sweden?-do we see the same pattern in Sweden? / Indikatorer av finansiella kriser - Ser vi samma mönster i Sverige?

Hedin, Fredrik, Johansson, Jonathan January 2017 (has links)
This paper aims to find macroeconomic and financial variables with ability to predict financial crises. A dataset covering 17 developed countries over the period 1870-2013 have been investigated using a logit model. We found commonly used macroeconomic variables such as terms of trade and consumption to be strong predictors within our sample. Whereas private debt and house prices are frequently found to be strong predictors, we found loans to business to be at least as good in predicting financial crises. Multivariate models are constructed as warning systems and used to analyze Sweden from 1975 up until 2016. The most efficient warning system give a strong signal before the first and moderate signal before the second crisis. In extension, regarding today’s climate the warning system provides no signal, suggesting low current risk. Policy makers can benefit from observing certain variables that are found significant in this study to improve financial stability and reduce socio-economic costs.

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