I dagsläget finns det fler anslutna enheter till internet, Internet of Things-enheter som det benämns, än vad det finns människor på jorden och produkter är lättillgängliga för den vanliga konsumenten. När fler enheter kopplas upp till internet är det också viktigt att hålla reda på dem. En nackdel med allt ökat antal uppkopplade enheter är en potentiellt ökad sårbarhet och det finns en högre risk för privatpersoner eller företag att bli hackade. Examensarbetet undersöker vilka säkerhetsrisker som finns med att skapa ett IoT-system och hur IoT kan kombineras med blockchainteknik ur ett säkerhetsperspektiv i olika branscher genom att titta på IoT-system inom små företag och för privatpersoner med begränsad IT-kompetens. En riskanalys görs för två användarfall, en floristverksamhet för bevarandet av bland annat känsliga växter och blommor respektive ett kommersiellt smart dörrlås som gör det möjligt för hushåll att kunna låsa samt låsa upp ett dörrlås digitalt med hjälp av mobiltelefoner. Därefter presenteras sårbarheter och tillgångar som behöver skyddas och relaterade arbeten undersöks för att se hur sårbarheter kan undvikas. Resultatet visar teknikernas relevans i nuläget, vilka IoT-modeller det finns och hur blockchain kan användas för att säkra IoT med exempelvis användningen av smarta kontrakt. Tre modeller identifieras där graden för inklusion av blockchain skiljer sig. IoT till IoT-modellen lagrar en del av datat i blockchain medan IoT interaktioner sker utan att använda blockchain. IoT till blockchain-modellen innebär att alla interaktioner sker via blockchain. Den tredje modellen är en hybrid vilket innebär att en del av interaktionen och datat placeras i blockchain och att det går att välja vilka interaktioner som ska ske via blockchain. Resultatet visar att blockchain kan användas för att bevara integritet och konfidentialitet mellan IoT enheter, mer specifikt kan det användas för autentisering och säker dataöverföring.

The electricity sector has a huge role in decarbonization of the energy system in order to meet climate targets and achieve net zero emission goals in different countries across the world. Present day electric power systems are increasingly dependent on less carbon intensive renewable energy sources for power generation. Rapid penetration of renewables leads to an increase in distributed generation and active consumer participation resulting in complex interactions within the power system. Therefore, traditional electric power grids are evolving to smart grids with the help of information and communication advancements. As a result, there is greater integration of Information Technology (IT) and Operational Technology (OT) actors, inclusion of clean energy sources, improved connectivity, sustainable supply and demand balance management of power etc. However, this sustainable transition gives rise to new attack points for malicious actors, who intend to disrupt the functioning of these smart grids. Therefore, this study aims to identify and analyse the most significant risks to smart grids in the next 10 years. The methodology for this research is two-fold: reviewing state-of-the-art research publications on smart grid security and conducting a semi-qualitative power grid security assessment through interviews with experts across countries. False Data Injection (FDI), Denial of Service (DoS) and supply chain attacks are some of the most important threats according to these methods. Finally, findings from the two research methods are compared to provide a comprehensive overview of the most significant risks to smart grids. / Elsektorn har en enorm roll att spela när det gäller att minska koldioxidutsläppen från energisystemet för att uppfylla klimatmålen och uppnå nettonollutsläpp i länder runt om i världen. Dagens elsystem är alltmer beroende av mindre koldioxidintensiva förnybara energikällor för elproduktion. Den snabba utbyggnaden av förnybara energikällor leder till en ökning av distribuerad produktion och aktivt konsumentdeltagande, vilket leder till komplexa interaktioner inom elsystemet. Traditionella elnät håller därför på att utvecklas till smarta nät med hjälp av informations- och kommunikationsframsteg. Som ett resultat av detta sker en större integration av aktörer inom informationsteknik (IT) och driftsteknik (OT), införande av förnyelsebara energikällor, förbättrad konnektivitet, hållbar hantering av balans mellan konsumtion och produktion av el. Denna hållbara övergång ger dock upphov till nya ingångar för illasinnade aktörer som vill störa de smarta nätmens funktion. Syftet med denna studie är därför att identifiera och analysera de viktigaste riskerna för smarta nät under de kommande tio åren. Metoden för denna forskning är tvåfaldig: genomgång av de senaste forskningspublikationerna om säkerhet i smarta nät och en semikvalitativ bedömning av säkerheten i smarta nät genom intervjuer med experter från olika länder. FDI (False Data Injection), DoS (Denial of Service) och attacker mot leveranskedjan är några av de största hoten enligt dessa metoder. Slutligen jämförs resultaten från de två forskningsmetoderna för att ge en heltäckande översikt över de viktigaste riskerna för smarta nät.

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Electrification of the transport sector is an important step in reducing the global greenhouse gas (GHG) emissions. Compared to traditional internal combustion engine vehicles (ICEVs), electric vehicles (EVs) produce no tail-pipe emissions and could be coupled with responsible energy production from renewable energy sources to reduce coupled emissions of their operation. One particularly interesting segment of the transport sector is the light-duty trucks (LDTs) commonly utilized in last-mile distribution. These vehicles are responsible for the third largest GHG-emissions in the road transportation sector in Sweden and is not as detailly covered in existing research compared to heavy-duty and passenger vehicles. At the same time usage of these vehicles is increasing due to the rapid increase of e-commerce. The objective of this thesis therefore is to investigate the potential of electrification for LDTs in last-mile distribution, operating in Stockholm, Sweden. The study is conducted through a techno economical optimization along with a business model innovation coupled to the current last mile operation of three collaborating partner companies. In this way, real world cases are included in the study to reflect on the feasibility of electrification of these vehicles. Conclusions of the study shows that electrification of the LDTs in last-mile operation in Stockholm, Sweden is possible. However, it would require value-adding measures to gain economic profit when transitioning from ICEVs. In addition, there also exists practical challenges as there is a significant need for route charging for several vehicles in the analyzed company fleets. This implies that operational driving behavior is required to be reviewed to reduce the requirement of route charging. Additionally, there is a need for investigating how route charging could be supplied to the companies. / Elektrifiering av transportsektorn är ett viktigt steg för att minska de globala utsläppen av växthusgaser (GHG). Jämfört med traditionella fordon med förbränningsmotorer (ICEVs) ger elfordon (EVs) inga direkta avgasutsläpp och skulle kunna kopplas till ansvarsfull energiproduktion från förnybara energikällor för att minska de kopplade utsläppen från deras drift. Ett särskilt intressant segment av transportsektorn är de lätta lastbilarna (LDTs) som vanligtvis används i last-mile distribution. Dessa fordon är ansvariga för de tredje största utsläppen av växthusgaser inom vägtransportsektorn i Sverige och täcks inte lika ingående i befintlig forskning jämfört med tunga fordon och personbilar. Samtidigt ökar användningen av dessa fordon på grund av den snabba ökningen av e-handel. Syftet med denna avhandling är därför att undersöka potentialen för elektrifiering för LDTs i last-mile distribution, verksamma i Stockholm, Sverige. Studien genomförs genom en tekno-ekonomisk optimering tillsammans med en affärsmodellinnovation kopplad till den nuvarande verksamheten hos tre deltagande partnerföretag. På så sätt inkluderas verkliga fall i studien för att reflektera över genomförbarheten av elektrifiering av dessa fordon. Slutsatser av studien visar att elektrifiering av LDTs inom last-mile distribution i Stockholm, Sverige är möjlig. Det skulle dock kräva värdeskapande åtgärder för att få ekonomisk vinst vid övergången från ICEVs. Dessutom finns det praktiska utmaningar i och med ett stort behov av ruttladdning för flera fordon i de analyserade företagsflottan. Detta innebär att det operativa körbeteendet måste ses över för att minska kravet på ruttladdning. Dessutom finns ett behov av att undersöka hur ruttladdning på bästa sätt skulle kunna tillföras företagen.

Multiline anchors are a novel way to reduce the cost of arrays of floating offshore wind turbines (FOWTs), but their behavior is not yet fully understood. Through metocean characterization and dynamic simulations, this thesis investigates the effects of wind-wave misalignment on multiline anchor systems. Four coastal U.S. sites are characterized in order to develop IEC design load cases (DLCs) and analyze real-world misaligned conditions. Stonewall Bank, Oregon showed the highest 500-year extreme wave height, at 16.6 m, while Virginia Beach, Virginia showed the highest 500-year wind speed, at 56.8 m/s. Misalignment probability distributions, at all sites, are found to converge towards zero (aligned conditions) and become less variable as wind speed increases. This indicates that high misalignment angles are unlikely at high wind speeds. A simulation parameter study, spanning a range of wave directions, misalignment angles, and DLCs, is run in OpenFAST to explore how misalignment affects multiline anchor loading. The simulated anchor is connected to three IEA 15 MW FOWT models via a taut mooring system. The force on the multiline anchor is calculated by summing the three tension vectors from the mooring lines. The mean direction of this force is found to align closely with the wind; each mean is within 5.5° of the wind direction. Higher misalignment angles cause increases to the amount of directional variation about this mean. The magnitude of the multiline force is also examined. Mean force level is found to be nearly unaffected by misalignment. However, maximum force decreases significantly as misalignment angle increases, dropping as much as 23.3% in extreme conditions. This confirms current anchor design practice, which treats aligned metocean conditions as the peak load an anchor experiences. Standard deviation of multiline force also decreases with misalignment. The operational load case, DLC 1.6, shows a slight trend towards this, but the extreme case, SLC, shows a more pronounced drop of 32.4%. This suggests that anchor cyclic loading analyses could benefit from considering misalignment. Doing so could lead to lower estimates of the cyclic loading amplitudes that anchor designs must withstand, thus leading to smaller, cheaper anchors.

In traditional investment decision making, one tool commonly used is the mean variance model, also known as an expected-value variance (EV) model, which evaluates the anticipated payout of different assets with respect to uncertainty where portfolios with higher risk demand higher expected returns from an individual. This thesis adapts this framework to a cost setting where decision makers are evaluating alternative physical assets that carry lifetime cost uncertainty for maintenance. Specifically, this paper examines homeowner choices for their home plumbing systems in the event of a pinhole leak, a tiny pin-sized hole that forms in copper, drinking-water pipes. These leaks can cause substantial damage and cost homeowners thousands of dollars in repairs. Since pinhole leaks are not related to the age of pipe material, a homeowner is subject to the risk of additional costs if a pinhole leak occurs again despite their repair efforts. The EV cost model in this paper defines two discrete choices for the homeowner in the event of a leak; to apply a simple repair at lower cost and higher future cost uncertainty, or to replace their plumbing with new pipe material, usually made of plastic, at a higher upfront cost but lower likelihood of future expenses. The risk preference of homeowners are demonstrated by their repair strategy selection, as well as the level of cost they incur to reduce uncertainty. Risk neutral individuals will select the repair strategy with the lowest lifetime expected cost and high variance, while risk averse homeowners will prefer to replace their plumbing with higher cost but lower variance. Risk averse individuals are also exposed to indirect costs, which is an additional unobserved cost in the form of a risk premium the homeowner is willing to pay to remove all uncertainty of future pinhole leak expense. Expected costs and variances are also higher for regions in the U.S. that experience elevated leak incident rates, known as hotspots. Using this mean variance cost framework, indirect cost can be quantified for homeowners in hotspot regions and compared to the rest of the U.S. to evaluate the magnitude of pinhole leak risk. The EV cost model estimates risk premiums on pinhole leaks to be $442 for homeowners in hotspots and $305 for those in the rest of the U.S. Finally, this paper examines the impact of pinhole leak cost uncertainty on the U.S. economy. Of an estimated $692 million in annual pinhole leak costs to homeowners, this study estimates a lower bound cost of $54 million per year (7.8% of estimated national annual cost) in risk premium that homeowners would be willing to pay to avoid pinhole leak cost uncertainty. Information in this study on the role of risk in home plumbing decisions and indirect costs would be helpful to policymakers and water utility managers as they deal with infrastructure management decisions. Furthermore, the EV cost methodology established in this paper demonstrates an effective use of mean variance modeling under cost uncertainty. / Master of Science

This study was concerned with establishing the extent to which various components of the environment were exposed to the three toxic minerals, arsenic, mercury and lead. The concentration of these three elements were determined in groundwater and surface water, soil, plants, animals such as goats, and humans in potentially contaminated areas in the Limpopo Province of South Africa. The focus of the study was to assess the possible exposure to infants through ingestion to arsenic, mercury and lead. Comparison of the mineral content of water at the study sites with international and national drinking water standards, indicated water from Rooiberg, Leeupoort and Gravelotte are not fit for human consumption due to high arsenic and lead concentrations. Water at Gravelotte also has unacceptably high levels of mercury. The soil, plants, goat’s milk and mother’s milk at Rooiberg have higher levels of arsenic and lead than have been recorded for many other countries. Mother’s milk and goat’s milk are the main sources of arsenic, lead and mercury contamination at Rooiberg. It is therefore newborns and toddlers who are most at risk from exposure to arsenic and lead. This is a cause for environmental and health concerns, but as this research is only a base-line study, it is imperative that more comprehensive surveys of potentially toxic mineral contamination be conducted in the province. / Environmental Sciences / (M.Sc. (Environmental Science))

Thesis (MA (Political Science))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Nigeria’s ability to play a regional stabilizing role in the Gulf of Guinea is severely thwarted due to unresolved conflict in the Niger Delta. Stemming from agitation by local communities, it evolved from peaceful rallies into an armed insurgency with the youth as the vanguard, and the conflict has subsequently spread into neighbouring countries like Cameroon, Equatorial Guinea, and Benin. The aim of this study was to analyse the conflict in the Niger Delta, southern Nigeria in order to assess its impact on the political risk of the Gulf of Guinea. Taking the form of a political risk analysis, a means of forecasting potential pitfalls for an investing client to mitigate or manage risk, the study postulated that a country specific risk analysis would not be sufficient to analyse an integrated system like the Gulf of Guinea. Many scholars have suggested that regional analysis has become more important than national. In the context of Africa contagion effects, the spill over, positive as well as negative from one country to another, casts doubt on the value of assessing only a country specific risk analysis. Taking this phenomenon into account, a regional risk index was created in order to assess the regional implications of the conflict in the Niger Delta. The index consists of six variables chosen from four political risk frameworks, namely the Economist Intelligence Unit, the Business Environment Risk Intelligence, The Brink Model, and finally the International Country Risk Guide. The variables were chosen on their utility for regional political risk analysis and their status as major risk variables, universal risk variables employed by various risk frameworks. In the subsequent political risk analysis, the first four variables were rated as having a high risk while the latter two garnered a medium risk rating. As such the overall rating for the political risk of the Gulf of Guinea was found to be high. This study finds that conventional country specific risk models are still very much the preferred means of analysing risk, but that regional risk analysis would have to take a larger role in political risk analysis in the future. / AFRIKAANSE OPSOMMING: Nigerië se vermoë om ‘n streeks-stabiliserende rol in die Golf van Guinea te speel, word ernstig gedwarsboom deur die onopgeloste konflik in die Niger Delta. Die oorsprong van die konflik in vreedsame gemeenskaplike protestaksie vir meer regverdige verdeling van olie inkomste het uitgekring na gewapende konflik, beide in die Delta self en in buurlande Kameroen, Ekwatoriale Guinee en Benin. Hierdie studie het gepoog om die konflik in die Nigeriese Delta te bestudeer om die impak van politieke risiko op die Golf van Guinea te assesseer. Die studie het die vorm van ‘n politieke risiko analise aangeneem, ‘n middel van vooruitskatting om potensiële valstrikke aan ‘n kliënt wat wil belê uit te wys om sodoende konflik te verlig of te beheer. Die studie veronderstel dat ‘n landspesifieke konflik analise onvoldoende is om ‘n geïntegreerde sisteem soos die Golf van Guinea te analiseer. Met menige akademici wat voorstel dat streeksanalise belangriker geword het as die nasionale, word daar in die konteks van die gevolge van Afrika-besmetting, die oorloop daarvan van een land na ‘n ander, positief sowel as negatief, ‘n skaduwee gegooi op die waarde van die assessering van slegs ‘n landspesifieke konflik analise. Met hierdie fenomeen in gedagte, is ‘n streek risiko inhoud geskep om die implikasies vir die konflik in die Niger Deltastreek, te assesseer. Die inhoud is saamgestel uit ‘n verskeidenheid van ses variante gekies uit vier politieke risiko raamwerke, nl die ‘Ekonomist Intelligence Unit’, die ‘Business Environment Risk Intelligence’, die ‘Brink Model’ en ook die ‘International Country Risk Guide’. Die variante is gebruik vir hulle waarde vir streekspolitieke risiko analise, asook die belangrikheid van hulle hoof risiko veranderlikheid, ‘n universele Hoof risiko variant wat gebruik word in verskillende risiko raamwerke. In die gevolglike politieke risiko-analise, is die vier variante beskou as ‘n baie hoë risiko, terwyl die laaste twee as medium risiko beskou word. Dus is die algemene taksering vir die politiese risiko in die Golf van Guinea baie hoog. Die studie vind uiteindelik dat lande se spesifieke risiko modelle steeds die verkose manier is om risiko’s te analiseer, alhoewel politieke risiko analise ‘n groter rol sal speel in toekomstige streek risiko analise.

在網路環境日益成熟的今日，網路交易的安全性已被列為首要的課題，而「公開金鑰基礎建設(public key infrastructure, PKI)」被公認是在資訊安全應用領域中，少數能同時滿足「保護資料安全」、「身分驗證」、「訊息完整性」以及「交易不可否認性」的加密應用技術。 電子商務被運用於各行各業，其中旅遊產業是全球最大與成長最快的產業之ㄧ。許多網路旅行社已經在企業內部建置了企業資源規劃(enterprise resource planning, ERP)系統，使得幾乎全部的交易與旅遊的安排都可以在線上完成。為了確保資料交換的安全性，便可以使用PKI技術，使企業的ERP 成為受完整加密保護的服務網路。 網路旅遊業者是以網站營運的方式來進行與消費者的互動，除了基本的防護措施，如：防火牆、入侵偵測、弱點掃瞄等網路安全外，企業的資安政策的制定與執行都可減少企業所面臨的風險。 近年來資料外洩事件頻傳，客戶資料及公司智慧財產外洩可能導致罰鍰、訴訟、公司品牌形象的毀損等。政府積極推動個人資料保護法，為了提高約束力，立法、司法與行政部門決定聯手祭出「天文數字的重罰」加以遏止；加上惡意使用者偽卡盜刷、冒名使用，使得電子商務業者不得不審慎地去評估如何加強資訊安全，以維繫企業本身的利益及提高企業的競爭力。 PKI的技術是目前公認最可靠、最可被信任的方式，但建置的複雜性及高成本，使得PKI的推廣層面不夠普及；如何讓PKI由「技術」移轉成為成功的「應用」，故筆者在本論文中建議一個運作模式，讓網路旅行社可以在透過網際網路行銷擴大業務之餘，也能因應時勢所趨，提供給其客戶一個安全的網路交易環境。 / The safety of Internet transaction has been referred to as the most important task in this fully-developed world of Internet. And public key infrastructure, which can provide confidentiality, authentication, integrity and non-repudiation, is one of the most effective ways of encryption in the application of information security. The travel agency has been one of the largest industries in e-commerce. There are many enterprise resource planning systems built in online travel agencies, so that almost every transaction and tours can be arranged through the Internet. To provide a well-protected environment, enterprises can use PKI technology to ensure the safety of online data exchanging. Online travel agencies interact with consumers through the web-site. Not only the basic protection like firewall, intrusion detection, and vulnerability scanning but also the development and the executive of security policies can reduce the risk that enterprises may encounter. Fines, litigations and the company's brand image damages may come after data leakages such as information of clients or intellectual property of companies. Government has actively promoted personal data protection law and huge amount of fines to improve the bindings. Coupled with many fraud credit cards used by the malicious users, companies have to assess how to reinforce information security to maintain its profit and upgrade its competitiveness. PKI technology is recognized as the most reliable and trusted solution, but the complexities and high cost of implementation made it difficult to apply. So, the author here tries to provide a mode of operation for online travel agencies to not only extend its services by the Internet but also provide a safe Internet transaction environment for its clients.

The thesis evaluates several hundred one-day-ahead VaR forecasting models in the time period between the years 2004 and 2009 on data from six world stock indices - DJI, GSPC, IXIC, FTSE, GDAXI and N225. The models model mean using the AR and MA processes with up to two lags and variance with one of GARCH, EGARCH or TARCH processes with up to two lags. The models are estimated on the data from the in-sample period and their forecasting ac- curacy is evaluated on the out-of-sample data, which are more volatile. The main aim of the thesis is to test whether a model estimated on data with lower volatility can be used in periods with higher volatility. The evaluation is based on the conditional coverage test and is performed on each stock index sepa- rately. Unlike other works in this eld of study, the thesis does not assume the log-returns to be normally distributed and does not explicitly select a partic- ular conditional volatility process. Moreover, the thesis takes advantage of a less known conditional coverage framework for the measurement of forecasting accuracy.