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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.
41

Geographically Weighted Regression based Investigation of Transport Policies for Increased Public Transport Ridership : A Case Study of Stockholm / Utvärdering av transportpolicyer för ökat kollektivtrafikresande baserat på geografiskt viktad regression : En fallstudie för Stockholm

Klar, Robert Günther January 2021 (has links)
Public transport plays a vital role in society as the economy, the degree of sustainability and the qualityof life of a city is directly affected by transportation. A shift in modal share towards public transport isassociated with many benefits such as increased air quality and improved space allocation within thecity. To further promote public transport, an appropriate measure of competitiveness is required toevaluate the impact of past and future transport policies. This study introduces the journeys per capitaratio as a new way of measuring public transport competitiveness. Firstly, the key factors affecting thepublic transportation usage rate expressed as the journeys per capita ratio are identified to evaluatethe impact of public transport provider efforts. For this purpose, data for a total of 32 explanatoryvariables and a scope of 218 regions for seven consecutive time frames are collected. Secondly,geographically weighted regression (GWR) – a local regression-based spatial analysis technique – isperformed to test if the journeys per capita ratio is a suitable target variable to predict the impact ofcertain transport supply changes. A traditional global ordinary least square (OLS) model is conductedas well to compare if a local model could be more beneficial. The GWR and the OLS model are trainedwith the data of previous years and tested with data from the consecutive following years. Thirdly,further temporal and socio-economic based cluster analyses are performed to assess the validity andthe explanatory power of the journeys per capita ratio. The conducted analyses reveal that thejourneys per capita ratio is a superior measure for assessing public transport competitiveness.Goodness of fit statistics and estimation results demonstrate that the GWR model has betterprediction accuracy and is more capable of retrospectively predicting the impact of previous transportpolicies. / Kollektivtrafiken har en avgörande roll i samhället då ekonomin, graden av hållbarhet och städerslivskvalité är direkt påverkad av transport. En förändring av transportanvändning från bil motkollektivtrafik är förknippad med flera fördelar, såsom ökad luftkvalitet och förbättrad rumsligallokering inom staden. För att ytterligare främja kollektivtrafik krävs ett lämpligt mått påkonkurrenskraft för att utvärdera effekterna av tidigare och framtida transportpolitik. Den här studienintroducerar resor per capita-förhållanden som ett nytt sätt att mäta kollektivtransportenskonkurrenskraft. För det första identifieras nyckelfaktorerna som påverkar användningsgraden förkollektivtrafik, uttryckt som förhållandet resor per capita för att utvärdera effekten avkollektivtrafikleverantörens insatser. För det här syftet har data för totalt 32 variabler och ett omfångav 218 regioner under sju, på varandra, följande tidsramar har samlats in. För det andra har Geografisktviktad regression (GWR), vilket är en lokal regressionsbaserad rumslig analysteknik, använts för atttesta om resor per capita-förhållanden är en lämplig målvariabel för att förutsäga effekterna av vissatransportförändringar. En traditionell Global ordinary least square model (OLS) har också använts föratt jämföra om en lokal modell är mer fördelaktig. GWR och OLS modellerna har tränats med data fråntidigare år och testats med data från följande år. För det tredje har ytterligare tidsmässigsocioekonomisk baserad klusteranalys utförts för att bedöma validiteten och förklaringsförmågan förresornas förhållande per capita. De genomförda analyserna pekar på att förhållandet resor per capitaär ett fördelaktigt mått för att bedöma kollektivtrafikens konkurrenskraft. Goodness of fit statistics ochde uppskattade resultaten visar att GWR-modellen har en bättre förmåga att göra noggrannaförutsägelser och är mer kapabel att i efterhand förutsäga effekterna av tidigare transportpolitik.
42

Cooperating broadcast and cellular conditional access system for digital television

Shirazi, Hamidreza January 2009 (has links)
The lack of interoperability between Pay‐TV service providers and a horizontally integrated business transaction model have compromised the competition in the Pay‐TV market. In addition, the lack of interactivity with customers has resulted in high churn rate and improper security measures have contributed into considerable business loss. These issues are the main cause of high operational costs and subscription fees in the Pay‐TV systems. This paper presents a novel end‐to‐end system architecture for Pay‐TV systems cooperating mobile and broadcasting technologies. It provides a cost‐effective, scalable, dynamic and secure access control mechanism supporting converged services and new business opportunities in Pay‐TV systems. It enhances interactivity, security and potentially reduces customer attrition and operational cost. In this platform, service providers can effectively interact with their customers, personalise their services and adopt appropriate security measures. It breaks up the rigid relationship between a viewer and set‐top box as imposed by traditional conditional access systems, thus, a viewer can fully enjoy his entitlements via an arbitrary set‐top box. Having thoroughly considered state‐of‐the‐art technologies currently being used across the world, the thesis highlights novel use cases and presents the full design and implementation aspects of the system. The design section is enriched by providing possible security structures supported thereby. A business collaboration structure is proposed, followed by a reference model for implementing the system. Finally, the security architectures are analysed to propose the best architecture on the basis of security, complexity and set‐top box production cost criteria.
43

Plastic card frauds, a survey of current relevant card and system properties / Plastkortsystem och brottsmöjligheter, en genomgång av egenskaper hos kort och läsare

Savostyanova, Natalia, Velichko, Valeriya January 2004 (has links)
<p>Recently the society has been turning from the use of paper-based technologies to plastic cards in certain spheres of our life. With the emergence and proliferation of high technologies we cannot content with the security provided bypaper only. Therefore the society has chosen plastic to protect its information because it offers far more security based not only on human perception but also on machine-readable elements. </p><p>The number of plastic cards in circulation in different spheres of our everyday life increases constantly. They replace money, documents and allow easy and safe access to some services. In spite of its security the plastic card however is subjected to fraud. </p><p>Plastic card fraud results in significant losses for the various industries. Since the first appearance of plastic cards methods of committing fraud have changed dramatically. Now there is a wide range of high technologies at the disposal of criminals as well as card manufacturers. </p><p>Therefore we have put the great emphasize of this work on the analysis of the most common card technologies in the Plastic Card World, the magnetic stripe and the chip, existing crimes and main means of their committing. And we also have revealed the weak and strong sides of the prevention techniques, which are currently in use.</p>
44

Plastic card frauds, a survey of current relevant card and system properties / Plastkortsystem och brottsmöjligheter, en genomgång av egenskaper hos kort och läsare

Savostyanova, Natalia, Velichko, Valeriya January 2004 (has links)
Recently the society has been turning from the use of paper-based technologies to plastic cards in certain spheres of our life. With the emergence and proliferation of high technologies we cannot content with the security provided bypaper only. Therefore the society has chosen plastic to protect its information because it offers far more security based not only on human perception but also on machine-readable elements. The number of plastic cards in circulation in different spheres of our everyday life increases constantly. They replace money, documents and allow easy and safe access to some services. In spite of its security the plastic card however is subjected to fraud. Plastic card fraud results in significant losses for the various industries. Since the first appearance of plastic cards methods of committing fraud have changed dramatically. Now there is a wide range of high technologies at the disposal of criminals as well as card manufacturers. Therefore we have put the great emphasize of this work on the analysis of the most common card technologies in the Plastic Card World, the magnetic stripe and the chip, existing crimes and main means of their committing. And we also have revealed the weak and strong sides of the prevention techniques, which are currently in use.
45

Postranní kanály u Smart Card / Smart Card side channels

Pospíšil, Karel January 2011 (has links)
The thesis is dealing with smart cards and describes the known types of side channel attacks. Smart card belongs into the group of the youngest and smartest cards. In the card body, made mostly from PVC, there is a chip inserted which contains a microprocessor.Side channel attacks are trying to use the leaking information from the physical implementation of the system while processing the cryptographic algorithm. The attacker is trying to use the leaking sensitive information because under certain circumstances it can be dependent on the input data. The theoretical part is devoted to description of smart cards, their types and their safety. It describes the classification of attacks on smart cards and includes the overview of selected cryptographic algorithms used in smart cards. It also describes selected physical and logical attacks and the most frequent side channel attacks. The thesis furthermore describes possibilities of measuring the voltage-current side channel. The practical part deals with used software and hardware. This section is devoted to the measurement of power specification of smart cards and to the analysis of processed information, using the oscilloscope and workstation with AD 622 card and Simulink development environment.
46

Systémy platebních karet / Payment card systems

Flégl, Jan January 2011 (has links)
The work is about payment card systems. We’d like to describe infrastructure of credit cards, ATMs, POS terminals , focusing on the EMV standard. In theoretical part we will be introduced with the history and development of credit cards, ATMs and POS terminals. Then we focus on a detailed description of payments terminals and possibilities of payment via the Internet. The most extensive theoretical part deals width EMV standard. In practical part we will make our own program, which authenticates the user based on his credit card and it will allow the user to login in the system. Source codes of this application can be found on enclosed CD.
47

Elektronický geocaching / Electronic geocaching

Průcha, Jan January 2013 (has links)
The master’s thesis is focusing on electronization of worldwide known game geocaching. It contains introduction to classic geocashing, analysis of current status and outline of possible solution. The design of electronization is based on smart card Gemalto. Very important part of the thesis is cryptographic security, therefore there is explanation of symetric and asymetric cryptography. The digital signature of transmitted message is realized by RSA algorithm, which is supported by the Gemalto smart card. Due to future expandability, it is appropriate to use general protocol. For this reason was chosen the ACP protocol which the supervisor of thesis adviced. In the following part, there is introduction to smart cards, their types and detailed description of Gemalto smart card. In the chapter 7 starts the solution of this issue and there are described the programmed apps.
48

Bezpečnost protokolů bezkontaktních čipových karet / Security of Contactless Smart Card Protocols

Henzl, Martin January 2016 (has links)
Tato práce analyzuje hrozby pro protokoly využívající bezkontaktní čipové karty a představuje metodu pro poloautomatické hledání zranitelností v takových protokolech pomocí model checkingu. Návrh a implementace bezpečných aplikací jsou obtížné úkoly, i když je použit bezpečný hardware. Specifikace na vysoké úrovni abstrakce může vést k různým implementacím. Je důležité používat čipovou kartu správně, nevhodná implementace protokolu může přinést zranitelnosti, i když je protokol sám o sobě bezpečný. Cílem této práce je poskytnout metodu, která může být využita vývojáři protokolů k vytvoření modelu libovolné čipové karty, se zaměřením na bezkontaktní čipové karty, k vytvoření modelu protokolu a k použití model checkingu pro nalezení útoků v tomto modelu. Útok může být následně proveden a pokud není úspěšný, model je upraven pro další běh model checkingu. Pro formální verifikaci byla použita platforma AVANTSSAR, modely jsou psány v jazyce ASLan++. Jsou poskytnuty příklady pro demonstraci použitelnosti navrhované metody. Tato metoda byla použita k nalezení slabiny bezkontaktní čipové karty Mifare DESFire. Tato práce se dále zabývá hrozbami, které není možné pokrýt navrhovanou metodou, jako jsou útoky relay.
49

A framework to implement delegation in offline PACS : A strategy to restrict user’s path

Bharath, Tati January 2013 (has links)
Physical access control systems (PACS) deal with the security of the availability of resources. They work as an alternative to traditional manual security access control. Access control has two variants, the logical which deals with computer environments and the physical which deals with the physical entry into a property or warehouses. However, offline physical access control systems cannot enforce the user’s path making it unsuitable for use in classified areas, such as places where the public is restricted. Therefore, offline PACS need a framework that can delegate the authority to enforce the user’s path. This is satisfactorily met in the presented research with a new design of offline PACS that has the capability to implement delegation. This framework allows the locks to dynamically write and read access policies onto and from a smart card. It works by means of a construct called “Path Array” and communication among different entities occurs via a chain of trust formed with the use of pre-shared keys.
50

Mobility Knowledge Graph and its Application in Public Transport

Zhang, Qi January 2023 (has links)
Efficient public transport planning, operations, and control rely on a deep understanding of human mobility in urban areas. The availability of extensive and diverse mobility data sources, such as smart card data and GPS data, provides opportunities to quantitatively study individual behavior and collective mobility patterns. However, analyzing and organizing these vast amounts of data is a challenging task. The Knowledge Graph (KG) is a graph-based method for knowledge representation and organization that has been successfully applied in various applications, yet the applications of KG in urban mobility are still limited. To further utilize the mobility data and explore human mobility patterns, the included papers constructed the Mobility Knowledge Graph (MKG), a general learning framework, and demonstrated its potential applications in public transport. Paper I introduces the concept of MKG and proposes a learning framework to construct MKG from smart card data in public transport networks. The framework captures the spatiotemporal travel pattern correlations between stations using both rule-based linear decomposition and neural network-based nonlinear decomposition methods. The paper validates the MKG construction framework and explores the value of MKG in predicting individual trip destinations using only tap-in records. Paper II proposes an application of user-station attention estimation to understand human mobility in urban areas, which facilitates downstream applications such as individual mobility prediction and location recommendation. To estimate the 'real' user-station attention from station visit counts data, the paper proposes a matrix decomposition method that captures both user similarity and station-station relations using the mobility knowledge graph (MKG). A neural network-based nonlinear decomposition approach was used to extract  MKG relations capturing the latent spatiotemporal travel dependencies. The proposed framework is validated using synthetic and real-world data, demonstrating its significant value in contributing to user-station attention inference. / Effektiv planering, drift och kontroll av kollektivtrafik är beroende av end jup förståelse för mänsklig rörlighet i stadsområden. Tillgången till omfattande och varierande källor av rörlighetsdata, såsom data från smarta kort och GPS-data, ger möjligheter att kvantitativt studera individuellt beteende och kollektiva rörlighetsmönster. Att analysera och organisera dessa stora mängder data är dock en utmanande uppgift. Kunskapsgrafen (KG) är en grafba serad metod för kunskapsrepresentation och organisering som har tillämpats framgångsrikt inom olika områden, men användningen av KG inom urbana rörlighetsområden är fortfarande begränsad. För att ytterligare utnyttja rörlighetsdata och utforska mänskliga rörlighetsmönster har de inkluderade artiklarna konstruerat Mobility Knowledge Graph (MKG), en allmän inlärningsram, och visat dess potentiella tillämpningar inom kollektivtrafiken. Artikel I introducerar begreppet MKG och föreslår en inlärningsram för att konstruera MKG från data från smarta kort i kollektivtrafiknätverk. Ramverket fångar de rumsligt-temporala resmönstersambanden mellan stationer genom att använda både regelbaserade linjära dekomponeringsmetoder och neurala nätverksbaserade icke-linjära dekomponeringsmetoder. Artikeln validerar MKG-konstruktionsramverket och utforskar värdet av MKG för att förutsäga enskilda resmål med endast tap-in-register. Artikel II föreslår en tillämpning av uppskattning av användar-stations uppmärksamhet för att förstå mänsklig rörlighet i stadsområden, vilket underlättar efterföljande tillämpningar såsom individuell rörlighetsförutsägelse och platsrekommendationer. För att uppskatta den ’verkliga’ användar-stations uppmärksamheten från data om besöksantal på stationer föreslår artikeln en matrisdekomponeringsmetod som fångar både användarlikhet och station-stationsrelationer med hjälp av Mobility Knowledge Graph (MKG). En neural nätverksbaserad icke-linjär dekomponeringsmetod användes för att extrahera MKG-relationer som fångar de latenta rumsligt-temporala resberoendena. Det föreslagna ramverket valideras med hjälp av syntetiska och verkliga data och visar på dess betydande värde för att bidra till inferens av användar-stationsuppmärksamhet. / <p>QC231116</p>

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