Un système temps réel critique nécessite une validation temporelle utilisant un test d'ordonnançabilité avant sa mise en œuvre. Cette thèse traite le problème d'ordonnancement des taches à offset (transactions) sur une architecture monoprocesseur, en priorités fixes et en priorités dynamiques. Les méthodes existantes pour un test exact ont une complexité exponentielle et seules existent des méthodes approchées, donc pessimistes, qui sont pseudo-polynomiales. En priorités fixes nous proposons des méthodes pseudo-polynomiales, basées sur l'analyse de temps de réponse qui sont moins pessimistes que les méthodes existantes. Nous présentons quelques propriétés (accumulativité monotonique, dominance de tâches) rendant exacte les méthodes d'analyse approchées pour certains cas de systèmes, et optimisant le temps de calcul. En priorités dynamiques, nous proposons un test d'ordonnançabilité exact avec une complexité pseudo-polynomiale. Ce test est basé sur l'analyse de la demande processeur. Les qualités des résultats de nos méthodes sont confirmées par des évaluations expérimentales.

Recent advances in pervasive computing and peer-to-peer computing have opened up vast opportunities for developing collaborative applications. To benefit from these emerging technologies, there is a need for investigating techniques and tools that will allow development and deployment of these applications on mobile and heterogeneous platforms. To meet these challenging tasks, we need to address the typical characteristics of mobile peer-to-peer systems such as frequent disconnections, frequent network partitions, and peer heterogeneity. This research focuses on developing the necessary models, techniques and algorithms that will enable us to build and deploy collaborative applications in the Internet enabled, mobile peer-to-peer environments. This dissertation proposes a multi-state transaction model and develops a quality aware transaction processing framework to incorporate quality of service with transaction processing. It proposes adaptive ACID properties and develops a quality specification language to associate a quality level with transactions. In addition, this research develops a probabilistic concurrency control mechanism and a group based transaction commit protocol for mobile peer-to-peer systems that greatly reduces blockings in transactions and improves the transaction commit ratio. To the best of our knowledge, this is the first attempt to systematically support disconnection-tolerant and partition-tolerant transaction processing. This dissertation also develops a scalable directory service called PeerDS to support the above framework. It addresses the scalability and dynamism of the directory service from two aspects: peer-to-peer and push-pull hybrid interfaces. It also addresses peer heterogeneity and develops a new technique for load balancing in the peer-to-peer system. This technique comprises an improved routing algorithm for virtualized P2P overlay networks and a generalized Top-K server selection algorithm for load balancing, which could be optimized based on multiple factors such as proximity and cost. The proposed push-pull hybrid interfaces greatly reduce the overhead of directory servers caused by frequent queries from directory clients. In order to further improve the scalability of the push interface, this dissertation also studies and evaluates different filter indexing schemes through which the interests of each update could be calculated very efficiently. This dissertation was developed in conjunction with the middleware called System on Mobile Devices (SyD).

本研究係探討關係人交易雙方是否委任相同會計師進行查核，對企業負債資金成本之效果。本文以企業利息費用除以平均帶息負債衡量企業之負債資金成本，企業之關係人交易部分則分成關係人銷貨交易、關係人進貨交易、關係人應收款、關係人應付款等四類型交易，來討論關係人交易與企業負債資金成本之關聯，接著將各類型關係人交易再細分成由相同會計師查核關係人交易雙方與由不同會計師查核關係人交易雙方兩類，以檢驗相同會計師查核對於企業負債資金成本之影響。 研究結果發現關係人交易與企業負債資金成本之關聯並無統計上之顯著性。然將關係人交易進一步拆分為是否由相同會計師查核關係人交易雙方後，關係人進貨交易與關係人銷貨交易等兩類型交易若由相同會計師查核交易雙方，其相較於不同會計師查核能夠有效減緩企業負債資金成本增加之情形。 / This study examines the effect of same auditor auditing both sides of related party transactions (RPTs) on cost of debt. In this study, cost of debt is measured using interest expenses divided by average interest bearing debt and we hand collect from annual reports the data of the four common types of RPTs: sales to related parties, purchases from related parties, accounts receivable from related parties and accounts payable to related parties. For the four types, we further split RPTs into RPTs whose involved sides are audited by the same auditor and RPTs whose involved sides are audited by different auditors. We do not find any evidence that RPTs are associated with cost of debt. However, we find that for sales to related parties and purchases from related parties, RPTs whose involved sides are audited by the same auditor are associated with cost of debt less strongly than RPTs whose involved sides are audited by different auditors. Our results suggest that same auditor auditing can mitigated the detrimental effect of RPTs on cost of debt.

Dans le domaine des transactions et du paiement électronique avec une carte à puce, le standard de communication en champ proche « Near Field Communication » (NFC) s’est imposé comme la technologie des transactions sans contact mobiles sécurisées pour le paiement, le contrôle d’accès, ou l’authentification. Les services sans contact mobiles sécurisés sont basés sur le mode émulation de carte du standard NFC qui implique une composante matérielle à accès restreint de type carte à puce appelée « Secure Element » (SE) dans laquelle sont stockées les données confidentielles et les fonctions sensibles. Malgré les efforts de standardisation de l'écosystème, les modèles proposés pour la mise en œuvre du SE sont complexes et souffrent du manque de généricité, à la fois pour offrir des mécanismes d’abstraction, pour le développement d’applications de haut niveau, et pour la mise en œuvre et la vérification des contraintes de sécurité des applications.L’objectif de la thèse est de concevoir et réaliser un environnement logiciel basé sur un modèle générique compatible avec les standards établis et peu sensible aux évolutions technologiques. Cet environnement devrait permettre à des non-experts de développer des applications multiplateformes, multimodes, multi-facteurs de forme, qui s’interfacent avec le SE dans un smartphone NFC. / In the field of electronic transactions and payment with a smart card, the Near Field Communication (NFC) standard has stood out against other candidate technologies for secure mobile contactless transactions for payment, access control, or authentication. Secure mobile contactless services are based on the card emulation mode of the NFC standard which involves a smart card type component with restricted access called "Secure Element" (SE) in which sensitive data and sensitive functions are securely stored and run. Despite considerable standardization efforts around the SE ecosystem, the proposed models for the implementation of SE are complex and suffer from the lack of genericity, both to offer abstraction mechanisms, for the development of high-level applications, and for the implementation and verification of applications security constraints.The objective of the thesis is to design and realize a software environment based on a generic model that complies with established standards and which is not very sensitive to technological evolutions. This environment should enable non-experts to develop multi-platform, multi-mode, multi-factor SE-based applications running into the NFC smartphone.

Topic: Legal Regulation of Payment Transactions Author: Bc. Pavel Martiník Supervisor: JUDr. Petr Kotáb, Ph.D. Regulation of payment services plays a key role in this era driven by escalating digitalization. The aim of this Thesis is to depict current challenges that this area of financial law faces and to propose a basis for regulation that can be implemented in the Czech Republic. The main topic of this Thesis is virtual currencies, more specifically Bitcoins and their status within the system of payment services regulations. After a short introduction, the first chapter of this Thesis describes theoretical background of payment services regulation, especially general and specific aims of legislation in this area of financial law, by addressing it in full context of private and public law. Besides that, it also briefly illustrates the history of payment services and money. The next chapter deals with current regulation that has been adopted in the Czech Republic. Besides virtual currencies, electronic money is discussed in full detail due to its similar features with virtual currencies. Furthermore, foreign regulation of payment systems is briefly described in order to provide a comparison with the Czech Republic. Therefore, both Czech and foreign regulations dealing with virtual currencies that...

Hybrid Wireless Networks (HWNs) are composite networks comprises of different technologies, possibly with overlapping coverage. Users with multimode terminals in HWNs are able to initiate connectivity that best suits their attributes and the requirements of their applications. There are many complexities in hybrid wireless networks due to changing data rates, frequency of operation, resource availability, QoS and also, complexities in terms of mobility management across different technologies. A superstore is a very large retail store that serves as a one-stop shopping destination by offering a wide variety of goods that range from groceries to appliances. It provide all types services such as banking, photo center, catering, etc. The good examples of superstores are: Tesco (hypermarkets, United Kingdom), Carrefour(hypermarkets, France), etc. Generally, the mobile customer communicates with superstore server using a transaction. A transaction corresponds to a finite number of interactive processes between the customer and superstore server. A few superstore transactions, examples are, product browsing, Technical details inquiry, Financial transactions, billing, etc. This thesis aims to design and develop the following schemes to solve some of the above indicated problems of a hybrid wireless superstore network: 1 Transaction based bandwidth management. 2 Transaction-based resource management. 3 Transaction-based Quality of Service management. 4. Transactions-based topology management. We, herewith, present these developed schemes, the simulation carried out and results obtained, in brief. Transaction-based bandwidth management The designed Transaction-Based Bandwidth Management Scheme (TB-BMS) operates at application-level and intelligently allocates the bandwidth by monitoring the profit oriented sensitivity variations in the transactions, which are linked with various profit profiles created over type, time, and history of transactions. The scheme mainly consists of transaction classifier, bandwidth determination and transactions scheduling modules. We have deployed these scheme over a downlink of HWNs, since the uplink caries simple quires from customers to superstore server. The scheme uses transaction scheduling algorithm, which decides how to schedule an outgoing transaction based on its priority with efficient use of available BW. As we observe, not all superstore transactions can have the same profit sensitive information, data size and operation type. Therefore, we classify the superstore transactions into four levels based on profit, data size, operation type and the degree of severity of information that they are handling. The aim of transaction classification module is to find the transaction sensitivity level(TSL) for a given transaction. The bandwidth determination module estimates bandwidth requirement for each of the transactions. The transactions scheduling module schedules the transactions based on availability of bandwidth as per the TSL of the transaction. The scheme schedules the highest priority transactions first, keeping the lowest priority transaction pending. If all the highest priority transactions are over, then it continues with next priority level transactions, and so on, in every slot. We have simulated the hybrid wireless superstore network environment with WiFi and GSM technologies. We simulated four TSL levels with different bandwidth. The simulation under consideration uses different transactions with different bandwidth requirements. The performance results describe that the proposed scheme considerably improves the bandwidth utilization by reducing transaction blocking and accommodating more essential transactions at the peak time of the business. Transaction-based resource management In the next work, we have proposed the transaction-based resource management scheme (TB-RMS) to allocate the required resources among the various customer services based on priority of transactions. The scheme mainly consists of transaction classifier, resource estimation and transactions scheduling modules. This scheme also uses a downlink transaction scheduling algorithm, which decides how to schedule an outgoing transaction based on its priority with efficient use of available resources. The transaction-based resource management is similar to that of TB-BMS scheme, except that the scheme estimates the resources like buffer, bandwidth, processing time for each of transaction rather than bandwidth. The performance results indicate that the proposed TB-RMS scheme considerably improves the resource utilization by reducing transaction blocking and accommodating more essential transactions at the peak time. Transaction-based Quality of Service management In the third segment, we have proposed a police-based transaction-aware QoS management architecture for the downlink QoS management. We derive a policy for the estimation of QoS parameters, like, delay, jitter, bandwidth, transaction loss for every transaction before scheduling on the downlink. We use Policy-based Transaction QoS Management(PTQM) to achieve the transaction based QoS management. Policies are rules that govern a transaction behavior, usually implemented in the form of if(condition) then(action) policies. The QoS management scheme is fully centralized, and is based on the ideas of client-server interaction. Each mobile terminal is connected to a server via WiFi or GSM. The master policy controller (MPDF) connects to the policy controller of the WiFi network (WPDF)and the GSM policy controller(PDF). We have considered the simulation environment similar to earlier schemes. The results shows that the policy-based transaction QoS management is improves performance and utilizes network resources efficiently at the peak time of the superstore business. Transactions-Aware Topology Management(TATM) Finally, we have proposed a topology management scheme to the superstore hybrid wireless networks. A wireless topology management that manages the activities and features of a wireless network connection. It may control the process of selecting an available access points, authentication and associating to it and setting up other parameters of the wireless connection. The proposed topology management scheme consists of the transaction classifier, resource estimation module, network availability and status module and transaction-aware topology management module. The TATM scheme is to select the best network among available networks to provide transaction response(or execution). We have simulated hybrid wireless superstore network with five WiFi and two GSM technologies. The performance results indicate that the transaction-based topology management scheme utilizes the available resources efficiently and distributed transaction loads evenly in both WiFi and GSM networks based on the capacity.

Thesis (MAcc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The use of derivative instruments, including single-stock futures, experienced unprecedented growth over the last twenty years. South Africa, like the rest of the world, is still experiencing extraordinary growth in the trading of these instruments. The taxation of these transactions, therefore, are of increasing practical importance. Despite this unprecedented growth, the South African tax policy makers have neglected the tax treatment of these instruments to a large extent. Due to the lack of specific legislative provisions regulating the tax aspects of these instruments, the general principles of the South African income tax law have to be applied. This gives rise to conflicting opinions regarding the tax treatment of these instruments, primarily as a result of the fact that these principles were developed long before the widespread use of derivative instruments. The lack of relevant case law in this regard is also problematic. This results in great uncertainty surrounding the tax treatment of profits from single stock futures. This research paper applies the general principles of the South African income tax law in order to determine when these profits accrue to the taxpayer and to determine the nature thereof. The introduction of capital gains tax has added yet a further dimension to the taxation of these instruments and is also considered. This research paper also considers the income tax treatment of similar instruments in Australia in order to identify useful principles that may be applied within a South African context. In light of the increasing volume and value of derivative transactions, it is imperative that clarity regarding the taxation of these transactions be obtained as soon as possible. Any reform and revised tax rules need to provide certainty to the taxpayer while remaining flexible enough to ensure that future changes in the ever-changing financial instruments environment are accommodated. / AFRIKAANSE OPSOMMING: Die gebruik van afgeleide instrumente, waaronder enkel-aandeeltermynkontrakte, het die afgelope twintig jaar ongekende groei beleef. Suid-Afrika, net soos die res van die wêreld, beleef steeds buitengewone groei in die verhandeling van hierdie instrumente. Die belasbaarheid van hierdie transaksies is gevolglik van toenemende praktiese belang. Ten spyte van hierdie ongekende groei, het die belastingbeleidmakers in Suid-Afrika tot ’n groot mate die belastinghantering van hierdie instrumente verwaarloos. Vanweë die gebrek aan spesifieke wetlike bepalings wat die belastingaspekte van laasgenoemde reguleer, moet die algemene beginsels van die Suid-Afrikaanse inkomstebelastingreg op hierdie instrumente toegepas word. Dié beginsels is egter reeds lank voor die wydverspreide gebruik van afgeleide instrumente ontwikkel en lei tot teenstrydige menings rondom die belastinghantering van hierdie instrumente. Die gebrek aan toepaslike regspraak in hierdie verband is ook problematies. Daar heers gevolglik groot onsekerheid oor die inkomstebelastinghantering van winste verdien uit enkel-aandeeltermynkontrakte. Hierdie navorsingswerkstuk pas die algemene beginsels van die Suid-Afrikaanse inkomstebelastingreg toe ten einde die tydstip waarop dié winste aan die belastingpligtige toeval en die aard daarvan te bepaal. Die inwerkingtreding van kapitaalwinsbelasting het nog 'n verdere aspek aan die belasbaarheid van hierdie instrumente toegevoeg en word ook oorweeg. Die navorsingswerkstuk oorweeg ook die inkomstebelastinghantering van soortgelyke instrumente in Australië ten einde nuttige beginsels te identifiseer wat binne Suid-Afrikaanse konteks toegepas kan word. Indien ag geslaan word op die toename in die aantal en waarde van transaksies in afgeleide instrumente, is dit noodsaaklik dat duidelikheid rakende die belasbaarheid daarvan so spoedig doenlik verkry word. Enige hervorming en hersiende belastingreëls moet sekerheid aan die belastingpligtige verskaf, maar moet terselfdetyd buigsaam genoeg wees om ruimte te skep vir toekomstige veranderinge binne die snelgroeiende finansiële instrumente-omgewing.

Thesis (LLM)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Inaedificatio entails that movables that have been permanently attached to land through building cease to exist as independent things and become part of the land. Courts have adopted different approaches over time to investigate whether or not inaedificatio had occurred. It is sometimes said that courts have moved away from the so-called traditional approach, which focused on the objective factors, to the so-called new approach, which places more emphasis on the subjective intention of the owner of the movables. This thesis analyses the applicable case law and concludes that there is inadequate proof of such a shift since both older cases associated with the traditional approach and later cases associated with the new approach emphasise the intention of the owner of the movables to establish whether accession had taken place. However, the case law does allow for a cautious different conclusion, namely that a certain line of both older and new cases emphasise the owner of the movable’s intention for commercial policy reasons, specifically to protect ownership of the movables in cases where ownership had been reserved in a credit sale contract. Constitutional analysis of these conclusions in view of the FNB methodology indicates that the courts’ decision to hold that accession had in fact occurred in cases that do involve permanent attachment of movables to land will generally establish deprivation of property for purposes of section 25(1) of the Constitution, but such deprivation would generally not be arbitrary since there would be sufficient reason for it. However, in cases where the courts decide that there was no accession because ownership of the movables had been reserved subject to a credit sale agreement, there is no deprivation of property because the landowner, who is the only one who might complain about the decision, could not prove a property interest for purposes of section 25(1). Moreover, the courts’ decision that accession had either occurred or not does not amount to expropriation under section 25(2) of the Constitution because there is no common law authority for expropriation. Therefore, the principal conclusion of the thesis is that the courts’ decision that accession had either occurred or not would generally be in line with the property clause of the Constitution. / AFRIKAANSE OPSOMMING: Inaedificatio behels dat roerende sake wat permanent deur bebouing aan grond vasgeheg is ophou bestaan as selfstandige sake en deel word van die grond. Die howe het in die verlede verskillende benaderings gevolg in hulle pogings om vas te stel of inaedificatio plaasgevind het. Daar word soms beweer dat die howe wegbeweeg het van die sogenaamde tradisionele benadering, wat op die objektiewe faktore gefokus het, na die sogenaamde nuwe benadering waarin die klem op die eienaar van die roerende goed se bedoeling val. Hierdie verhandeling analiseer die toepaslike regspraak en kom tot die gevolgtrekking dat daar onvoldoende bewys van so ‘n verskuiwing bestaan, aangesien sowel ouer sake wat met die tradisionele benadering geassosieer word en later regspraak wat die nuwe benadering sou volg klem op die eienaar van die roerende sake se bedoeling plaas. Die regspraak bied wel bewyse vir ‘n versigtige gevolgtrekking op ‘n ander punt, naamlik dat bepaalde ouer en later sake die eienaar van die roerende goed se bedoeling vir kommersiële beleidsredes beklemtoon, spesifiek in gevalle waar eiendomsreg in ‘n kredietkoop voorbehou is. Grondwetlike analise van hierdie gevolgtrekkings in die lig van die FNB-metodologie suggereer dat die howe se beslissing dat aanhegting wel plaasgevind het in gevalle waar permanente aanhegting van roerende goed aan grond ter sprake was oor die algemeen ‘n ontneming van eiendom vir doeleindes van artikel 25(1) van die Grondwet sal daarstel, maar aangesien daar oor die algemeen voldoende rede vir die ontneming is sal dit nie arbitrêr wees nie. Aan die ander kant, waar die howe beslis dat daar geen aanhegting was nie omdat eiendomsreg van die roerende goed vir sekerheid onderhewig aan ‘n kredietkoop voorbehou is, is daar geen ontneming van eiendom nie omdat die grondeienaar, die enigste party wat beswaar teen die beslissing mag maak, nie ‘n eiendomsbelang vir doeleindes van artikel 25(1) kan bewys nie. Verder stel die howe se beslissing dat aanhegting óf plaasgevind het al dan nie in elk geval geen onteiening daar nie aangesien daar geen magtiging vir onteiening in die gemenereg bestaan nie. Die gevolgtrekking van die verhandeling is dat die howe se beslissing dat aanhegting óf plaasgevind het al dan nie oor die algemeen nie in stryd met die eiendomsbepaling in die Grondwet sal wees nie.

Thesis (MBA (Business Management))--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Prior to 30 June 1999 companies in South Africa were not allowed to buy back their own shares. Amendments to the Companies Act, the Companies Amendment Act (Act 37 of 1999) radically changed the philosophy around capital maintenance. The result of this amendment is that a company is allowed to buy back its own shares and finance the backbuying of its shares under certain circumstances. A sample of 140 companies listed on the Johannesburg Securities Exchange for the period 2000 to 2005 was selected. The backbuying of shares by the relevant company, subsidiary and trust was analysed for the period 2000 to 2005. For the purposes of this empirical study, the financial sector, as well as the alternative exchange, that is focussed on good quality small and medium-sized high growth companies, were excluded during sample selection. The outcome of this exploratory study is the identification of the fact that a share buyback took place or not in Tables 4.1 and 4.2; a summary of the number of shares bought back in Table 4.3; and, in Table 4.4, a summary of the number of shares bought back, expressed as a percentage of the weighted average number of shares in issue. / AFRIKAANSE OPSOMMING: Maatskappye in Suid-Afrika was voor 30 Junie 1999 deur die Maatskappywet verbied om hul eie aandele terug te koop. Wysigings aan die Maatskappywet, naamlik die Wysigingswet op Maatskappye (wet 37 van 1999) het ’n radikale verandering bewerkstellig in die filosofie rakende kapitaalinstandhouding. Die gevolg van dié wysigingswetgewing is dat maatskappye sedert 30 Junie 1999 hul eie aandele kan terugkoop en in sekere omstandighede die aankoop van hul eie aandele finansier. ’n Steekproef van 140 genoteerde maatskappye op die Johannesburgse Aandelebeurs is geselekteer vir die tydperk 2000 tot 2005. Die terugkooptransaksies van aandele deur die betrokke maatskappy, filiaal en trust is opgesom vir die tydperk 2000 tot 2005. Hierdie empiriese ondersoek het die finansiële sektor, asook die alternatiewe beurs van die Johannesburgse Aandelebeurs, wat fokus op goeie kwaliteit klein en mediumgrootte maatskappye met groot groeipotensiaal, tydens die steekproefseleksie uitgesluit. Die resultate van hierdie empiriese ondersoek is die identifisering en opsomming van die terugkooptransaksies van aandele vir die steekproef in Tabelle 4.1 en 4.2; ’n opsomming in Tabel 4.3 van die getal aandele teruggekoop; en ’n opsomming in Tabel 4.4 van die getal aandele teruggekoop, uitgedruk as ’n persentasie van die gemiddelde getal uitgereikte aandele.

Security is becoming an increasingly important issue for business, and with it comes the need for appropriate authentication; consequently, it is becoming gradually more important to develop secure e-commerce systems. Fraud via the web, identity theft, and phishing are raising concerns for users and financial organisations. In addition, current authentication methods, like passwords, have many problems (e.g. some users write them down, they forget them, or they make them easy to hack). We can overcome these drawbacks by using biometric authentication systems. Biometric systems are being used for personal authentication in response to the rising issue of authentication and security. Biometrics provide much promise, in terms of preserving our identities without the inconvenience of carrying ID cards and/or remembering passwords. This research is important because the securing of e-commerce transactions is becoming increasingly important. Identity theft, hacking and viruses are growing threats to Internet users. As more people use the Internet, more identity theft cases are being reported. This could harm not only the users, but also the reputation of the organisations whose names are used in these illegal acts. For example, in the UK, online banking fraud doubled in 2008 compared to 2007. More users took to e-shopping and online banking, but failed to take necessary protection. For non-western cultures, the figures for web security, in 2008, illustrated that Saudi Arabia was ranked ninth worldwide for users who had been attacked over the web. The above statistics reflect the significance of information security with e-commerce systems. As with any new technology, user acceptance of the new technology is often hard to measure. In this thesis, a study of user acceptance of biometric authentication systems in e-transactions, such as online banking, within Saudi society was conducted. It examined whether Saudis are practically willing to accept this technology. This thesis focuses upon Saudi Arabia, which has developing economy. It has achieved a rapid rate of growth, and therefore makes an interesting and unique case study. From an economist's point of view, Saudi Arabia is the powerhouse of the Middle East. It has the leading regional economy, and, even though it is still relatively young. It has a young and rapid growing population; therefore, this makes Saudi Arabia an attractive potential market for all kinds of e-commerce applications. Having said that, with more than half of population under the age of 30 are more to be expected to take the risk of accepting new technology. For this work, 306 Saudi participants were involved in the experiments. A laboratory experiment was created that actively tested a biometric authentication system in combination with a survey. The Technology Acceptance Model (TAM) was adopted in the first experimental phase as the theoretical basis on which to develop the iv research framework, the model has proven its efficiency as a good predictor for the biometric authentication system. Furthermore, in a second experimental phase, the Unified Theory of Acceptance and Use of Technology (UTAUT) with moderating variables such as age, gender and education level was examined as a proposed conceptual framework to overcome the limitations of TAM. The aim of the study was to explore factors affecting users' acceptance of biometric authentication systems. The findings from Structural Equation Modelling (SEM) analysis indicate that education level is a significant moderating factor, while gender and age do not record as significant. This thesis added new knowledge to this field and highlighted the importance of the perceptions of users regarding biometric security technologies. It helps determine the factors affecting the acceptance of biometric technology. To our knowledge, this is the first systematic study of this issue carried out by academic and non-biased researchers in Saudi Arabia. Furthermore, the thesis presents security technology companies and developers of information security products with information to help in the determination of what is significant to their user base when taking into account the introduction of new secure systems and products.