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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.
411

Systematic Literature Review of the Adversarial Attacks on AI in Cyber-Physical Systems

Valeev, Nail January 2022 (has links)
Cyber-physical systems, built from the integration of cyber and physical components, are being used in multiple domains ranging from manufacturing and healthcare to traffic con- trol and safety. Ensuring the security of cyber-physical systems is crucial because they provide the foundation of the critical infrastructure, and security incidents can result in catastrophic failures. Recent publications report that machine learning models are vul- nerable to adversarial examples, crafted by adding small perturbations to input data. For the past decade, machine learning security has become a growing interest area, with a significant number of systematic reviews and surveys that have been published. Secu- rity of artificial intelligence in cyber-physical systems is more challenging in comparison to machine learning security, because adversaries have a wider possible attack surface, in both cyber and physical domains. However, comprehensive systematic literature re- views in this research field are not available. Therefore, this work presents a systematic literature review of the adversarial attacks on artificial intelligence in cyber-physical sys- tems, examining 45 scientific papers, selected from 134 publications found in the Scopus database. It provides the classification of attack algorithms and defense methods, the sur- vey of evaluation metrics, an overview of the state of the art in methodologies and tools, and, as the main contribution, identifies open problems and research gaps and highlights future research challenges in this area of interest.
412

A Proposal and Implementation of a Novel Architecture Model for Future IoT Applications : With focus on fog computing

Andersson, Viktor January 2022 (has links)
The number of IoT devices and their respective data is increasing for each day impacting the traditional architecture model of solely using the cloud for processing and storage in a negative way. This model may therefore need a supporting model to alleviate the different challenges for future IoT applications. Several researchers have described and presented algorithms and models with focus on distributed architecture models. The main issues with these however is that they fall short when it comes to the implementation and distribution of tasks. The former issue is that they are not implemented on actual hardware but simulated in a constrained environment. The latter issue is that they are not considering sharing a single task but to distribute a whole task. The objective of this thesis is therefore to present the different challenges regarding the traditional architecture model, investigate the research gap for the IoT and the different computing paradigms. Together with this implementing and evaluating a future architecture model capable of collaboration for the completion of a generated task on multiple off-the-shelf hardware. This model is evaluated based on task completion time, data size, and scalability. The results show that the different testbeds are capable communicating and splitting a single task to be completed on multiple devices. They further show that the testbeds containing multiple devices are performing better regarding completion time and do not suffer from noticeable scalability issues. Lastly, they show that the completion time drops remarkably for tasks that are split and distributed.
413

The adoption of Industry 4.0- technologies in manufacturing : a multiple case study

NILSEN, SAMUEL, NYBERG, ERIC January 2016 (has links)
Innovations such as combustion engines, electricity and assembly lines have all had a significant role in manufacturing, where the past three industrial revolutions have changed the way manufacturing is performed. The technical progress within the manufacturing industry continues at a high rate and today's progress can be seen as a part of the fourth industrial revolution. The progress can be exemplified by ”Industrie 4.0”; the German government's vision of future manufacturing. Previous studies have been conducted with the aim of investigating the benefits, progress and relevance of Industry 4.0-technologies. Little emphasis in these studies has been put on differences in implementation and relevance of Industry 4.0-technologies across and within industries. This thesis aims to investigate the adoption of Industry 4.0-technologies among and within selected industries and what types of patterns that exists among them. Using a qualitative multiple case study consisting of firms from Aerospace, Heavy equipment, Automation, Electronics and Motor Vehicle Industry, we gain insight into how leading firms are implementing the technologies. In order to identify the factors determining how Industry 4.0-technologies are implemented and what common themes can be found, we introduce the concept production logic, which is built upon the connection between competitive priorities; quality, flexibility, delivery time, cost efficiency and ergonomics. This thesis has two contributions. In our first contribution, we have categorized technologies within Industry 4.0 into two bundles; the Human-Machine-Interface (HMI) and the connectivity bundle. The HMI bundle includes devices for assisting operators in manufacturing activities, such as touchscreens, augmented reality and collaborative robots. The connectivity-bundle includes systems for connecting devices, collecting and analyzing data from the digitalized factory. The result of this master thesis indicates that depending on a firm’s or industry’s logic of production, the adoption of elements from the technology bundles differ. Firms where flexibility is dominant tend to implement elements from the HMI-bundle to a larger degree. In the other end, firms with few product variations where quality and efficiency dominates the production logic tends to implement elements from the connectivity bundle in order to tightly monitor and improve quality in their assembly. Regardless of production logic, firms are implementing elements from both bundles, but with different composition and applications. The second contribution is within the literature of technological transitions. In this contribution, we have studied the rise and development of the HMI-bundle in the light of Geels (2002) Multi-Level Perspective (MLP). It can be concluded that an increased pressure on the landscape-level in the form of changes in the consumer-market and the attitudes within the labor force has created a gradual spread of the HMI-bundle within industries. The bundles have also been studied through Rogers (1995) five attributes of innovation, where the lack of testability and observability prevents increased application of M2M-interfaces. Concerning Big Data and analytics, the high complexity prevents the technology from being further applied. As the HMI-bundle involves a number of technologies with large differences in properties, it is hard draw any conclusion using the attributes of innovation about what limits their application.
414

Integration of BIM and IoT to improve building performance for occupants’ perspecti

Thu Nguyen, Huong January 2016 (has links)
The purpose of this thesis is to describe and implement how a specific form of IoT, sensors, can be integrated with BIM in order to improve the building performance, when the perspective taken is the end-users. It seeks to explore different perceived values of BIM and sensor integration for the occupants who directly use the building facilities. The thesis also describes the concept, frameworks and cases of how BIM and sensors integration can be setup. These are used for an implementation at a case facility. Three main methods are used – literature review, comparative case study, and a smallscale implementation, containing a survey and sensor implementation based on the respondents’ satisfaction with the office air quality. A basic literature review is used to gather the fundamental concepts used within the relevant areas, and to review the empirical research connected to these. The conceptual part of the thesis review frameworks for BIM and sensor integration, and points toward a more user-centric framework that is later developed in relation to the thesis’ empirical results. The theoretical framework integrates Information Systems Theories with Knowledge Management for a framework of understanding how knowledge about new kinds of Information Systems in developing areas function. The empirical part of the thesis is structured into two main phases, one descriptive comparative case study, and the other an implementation based in the first phase results. The first phase is descriptive, where two cases of sensor and BIM implementation processes for FM are described. The main case of Tyréns company (Tyréns), and a reference case of Mästerhuset is used for understanding how different organizational structures may lead to different perceived values and processes of BIM and sensor integration for the end-users. The second phase is an implementation at the main case, Tyréns’ headquarter building. Here the end-user perspective is employed with a survey that is constructed in accordance with some of the fundamental concepts and research reviewed, in order to measure the perceived satisfaction with the air quality of the end-users working environment. The answers show concerns with air quality in the meeting rooms, and this is used as the basis for a small-scale implementation of sensors, where CO2 and temperature sensors are set up. The results show how different organizational-specific conditions generate different perceived values of BIM and sensor integration depending on ownership relation to the end-users. The case study also illustrate the different processes of BIM and sensor integration may be setup to supplement building performance. This points to a needed add-on into frameworks that conceptualizes BIM and sensor integration without the inclusion of the end-users’ perspective. Based on this an end-user conceptual framework of BIM and sensors is proposed with the supplementary part of a knowledge layer, named analytic layer and data source from occupants.
415

Security in Internet of Things

Song, Yuanjun January 2013 (has links)
The Internet of Things (IoT) is emerging the Internet and other networks with wireless technologies to make physical objects interact online. The IoT has developed to become a promising technology and receives significant research attention in recent years because of the development of wireless communications and micro-electronics.  Like other immature technological inventions, although IoT will promise their users a better life in the near future, it is a security risk, especially today the privacy is increasingly concerned by people. The key technologies of IoT are not yet mature. Therefore the researches and applications of the IoT are in the early stage. In order to make the IoT pervade people’s everyday life, the security of the IoT must be strengthened. In this thesis, first, the IoT is compared with the Internet. Though the IoT is based on the Internet, due to the characteristics of the IoT, those mature end-to-end security protocols and protective measures in the Internet can not directly provide the end-to-end data security through the perceptual layer, the transport layer the and application layer. For the IoT security addressing issues (such as the Internet DNS attack), this thesis proposes the IoT addressing security model. The traditional access control and the identity authentication only works in the same layer. The IoT addressing security model designed in this thesis effectively solves the issues of vertically passing the authentication results in the addressing process without changing the protocols for two communication parties. Besides, this thesis provides the object access control and privacy protection from the object application layer addressing, DNS addressing and IP addressing phases. Finally, combining the IoT object addressing security model with practical application scenario, this thesis designs the IoT object security access model. In this model, the access requester can access objects in different domains through a single sign-on. This model provides the protection for the end-to-end communication between the access requester and object.
416

Implementing Erlang/OTP on Intel Galileo

Coada, Paul, Kaya, Erkut January 2015 (has links)
The Intel Galileo, inspired by the well-known Arduino board, is a development board with many possibilities because of its strength. The Galileo is has an Intel processor capable of running GNU/Linux and can be connected to the internet, which opens up the possibility to be controlled remotely. The programming language that comes with the Intel Galileo is the same as for the Arduino development boards, and is therefore very limited and does not utilize the Galileo’s entire strength. Our aim with this project is to integrate a more suitable programming language; a language that can make better use of the relatively powerful processor to control the components of the board. The programming language of choice is Erlang, and the reason is obvious. Erlang can be described as a process-oriented programming language based on the functional programming paradigm and its power in concurrency. The result of the project was the successful integration of a complete version of GNU/Linux on the board and the cross-compilation of Erlang/OTP onto the board. Having Erlang running on the system opens up many possibilities for future work, amongst all: creating Erlang programs for the Intel Galileo, integrating an effective API, and measuring the pros and cons of using Erlang on an Intel Galileo. / Intel Galileo är ett utvecklingskort som bygger på Arduinos succe. Den kommer med en kraftigare processor jämfort med Arduino Uno, och den har möjlighet att kunna köra GNU/Linux. Den har också en port för att kunna kopplas till internet och på så sätt kommunicera med andra enheter. Programmeringsspråket som rekommenderas för Intel Galileo är densamma som används för Arduinos utvecklingskort. Det finns däremot en möjlighet att kunna kombinera utvecklingskortet med ett programmeringsspråk som kan erbjuda mer funktionalitet och fortfarande vara enkelt. Vårt val hamnade på Erlang för den är ett funktionellt språk och har möjlighet att hantera olika processer. Tanken är att kunna behandla olika komponenter kopplade till utvecklingskortet som processer, som kan kommunicera med andra komponenter och med internet. Projektarbetet bestod av att undersöka ifall det är möjligt att kunna kombinera Erlang/OTP med Intel Galileon samt skriva en guide för hur implementeringen gick till. Att kombinera de två var lyckat och det öppnar upp möjligheter för fortsätta arbeten och försök.
417

Security and privacy concerns for IoT adoption in the home domain : A user perspective

Schuster, Frederik January 2022 (has links)
Internet of Things (IoT) is an emerging technological revolution, a new paradigm, with the ability to improve our lives in many areas. Smart homes, smart buildings, smart cities, smart energy management, industrial processing, healthcare, logistics, transport, agriculture & farming, are a some of the areas where IoT is expected to make a big difference. The IoT growth has been almost exponential and is expected to reach between 20 and 43 billion smart devices by 2025., However, for the technology to be widely accepted and adopted, it needs to provide the users with benefits that upweights the cost and risks. but for the technology to be widely accepted and adopted by the users, it needs to provide the users with benefits that upweights the cost and risks. While new functionality is continuously added and the cost decreases with larger volumes and technological advances, the risk is also growing the more the technology is involved in our lives. An increasing number of serious incidents where threat sources gain unauthorized access, or personal data being disclosed or misused, have a negative impact on user adoption. However, producers and service providers prioritize putting their products on the market as fast as possible, and don’t seem to be aware that users find security and privacy as important as functionality. Therefore, it is of great importance that threat sources won’t be able to gain unauthorized access and that users’ personal data aren’t disclosed. However, producers and service providers prioritize putting their products on the market as fast as possible, and don’t seem to be aware that users are willing to pay as much for security and privacy as for new functionality.  It is however not enough to solve the worst issues. Most users are not experts and can’t assess the resilience of a system. Government, producers and service providers must therefore apply a user perspective, understanding and recognizing users concerns, and work actively towards gaining the trust of the users. While the research in security technology is in rapid progress, there is still fundamental research gaps in the perception of IoT security and privacy, the creation of trust, and the barriers for IoT adoption. This paper takes on a holistic approach to examine how producers and service providers can gain user trust and facilitate home IoT adoption
418

Deploying and Analyzing Air Quality Sensors in Mongolian Gers

Alcantara, Lehi Sttenio 05 April 2021 (has links)
The purpose of this research is to develop best practices for deploying air quality sensors in a remote location such as Mongolia. I discussed the architecture and design constraints when collecting remote air quality sensors data, the challenges that emerge while implementing a sensor-based network in a remote location such as Mongolia. The tradeoffs of using different architectures are described. I observed the usage of electrical heaters in modified gers in remote locations and conclude how effective they are in reducing PM2.5 levels by analyzing air quality data and go through the process of cleaning up the data and removing humidity from low-cost sensors used to deploy in a remote location such as Mongolia so that the PM2.5 reading is more accurate. In order to help many humanitarian efforts dealing with better air quality in developing countries, an air quality sensor was designed to keep low cost as much as possible. The cost is about $200 to build, which is cheaper than other low-cost sensors, yet provides more functionality (e.g., CO2 sensing) and used cellular connectivity to upload data in real-time. This sensor has implications beyond Mongolia. The sensor can be used anywhere WiFi connectivity is not available, such as parks, bus stops, and along roadways, breaking the constraints that other low-cost sensors have. Removing the need for WiFi is a necessary step in allowing ubiquitous air quality sensing. The contributions in this thesis are: First, I presented the challenges one should consider while deploying air quality sensors in developing countries. Second, since Mongolia offers a unique environment and constraints, I shared experiences in deploying sensors in a remote location like Mongolia. This experience goes beyond air quality sensors and can inform anyone who is deploying sensors in remote areas. Third the analysis of the PM2.5 on the gers gives us better insights as to whether modifying gers with insulation and using electrical heaters as opposed to burning coal to heat up the gers makes a difference in regard to better air quality in the gers.
419

RF Wireless Power Transfer for IoT Applications

Tavana, Morteza January 2022 (has links)
With the emergence of the Internet of things (IoT) networks, the replacement of batteries for IoT devices became challenging. In particular, the battery replacement is more expensive and cumbersome for scenarios where there are many IoT devices; or where the IoT devices are in unreachable locations; or when they have to be replaced often. Some IoT devices might be lost or forgotten, and there is a risk of hazardous chemicals leakage and e-waste in large scale in nature. Radio frequency (RF) wireless power transfer (WPT) is an alternative technology for powering those devices. It has been shown that only less than one millionth of the transmitted energy is absorbed by the receivers, the rest is absorbed by the objects in the environment. We can utilize the existing infrastructure for wireless communications such as base stations (BS) to charge IoT devices. The present work is devoted to analyze the feasibility and limitations of the battery-less operation of IoT devices with RF WPT technology and energy harvesting from existing infrastructure for wireless communications. We study the indoor and outdoor scenarios for powering of IoT devices. In the first scenario, we consider an outdoor environment where an IoT device periodically harvests energy from an existing BS and transmits a data packet related to the sensor measurement under shadow fading channel conditions. We analyze the limits (e.g., coverage range) of energy harvesting from a BS for powering IoT devices. We characterize the "epsilon-coverage range, where" is the probability of the coverage. Our analysis shows a tradeoff between the coverage range and the rate of sensor measurements, where the maximal "epsilon-coverage range is achieved as the sensor measurement rate approaches zero. We demonstrate that the summation of the sleep power consumption and the harvesting sensitivity power of an IoT device limits the maximal "epsilon-coverage range. Beyond that range, the IoT device cannot harvest enough energy to operate. The desired rate of the sensor measurements also significantly impacts the "epsilon-coverage range. We also compare the operational domain in terms of the range and measurement rate for the WPT and battery-powered technologies. In the second scenario, we consider the remote powering of IoT devices inside an aircraft. Sensors currently deployed on board have wired connectivity, which increases weight and maintenance costs for aircraft. Removing cables for wireless communications of sensors on board alleviates the cost, however, the powering of sensors becomes a challenge inside aircraft. We assume that the IoT devices have fixed and known locations inside an aircraft. The design problem is to minimize the number of WPT transmitters given constraints based on the cabin geometry and duty cycle of the IoT devices. We formulate a robust optimization problem to address the WPT system design under channel uncertainties. We also derive an equivalent integer linear programming and solve that for an optimal deployment to satisfy the duty cycle requirements of the cabin sensors. / <p>QC 20220223</p><p></p>
420

Digital lagring och användning av privat information i smarta hem : En studie med användarperspektiv / Digital storage and use of private information in smart homes

Lundgren, Fredrik, Hamberg, André January 2020 (has links)
Drömmen om ett smart hem som är helt automatiserat är snart inte en dröm längre. Uppkopplade enheter kan anpassa sig efter sin omgivning och efter givna situationer, vilket exempelvis gör det möjligt för kökslamporna att tändas när garageporten öppnas. Vidare har smarta hem möjligheten att öka livskvaliteten för användare genom att anpassa sig efter deras vanor och beteenden. Om enheterna ska kunna anpassa sig efter användarna och sin omgivning krävs det oerhört mycket information, som i fel händer skulle kunna få förödande konsekvenser för användaren. Dock finns det brister i säkerheten bland enheter och vissa produceras utan säkerhet i åtanke. Det finns flertalet säkerhetsrisker med smarta hem och studien har fokuserat på säkerhetsrisker med fokus på autentisering och beteendeanpassning, med ett användarperspektiv, då det är något som saknas i befintlig litteratur. Frågeställningen som behandlas i studien är: ”Hur ser användare av uppkopplade-enheter i smarta hem på säkerhet utifrån autentisering och beteendeanpassning?”. För att kunna besvara denna frågeställning har en kvantitativ metod tillämpats. En webbenkät utformades och testades i en pre-pilot studie och sedan i en pilotstudie innan den publicerades. Frågorna i enkäten har utvecklats från den teori som presenteras i det teoretiska ramverket. Resultatet visar på att användarna har en hög tilltro till säkerheten hos sina enheter och att en majoritet inte är oroliga över säkerhetsrisker kopplat till autentisering. Respondenterna är mer oroliga över säkerhetsrisker associerade med beteendeanpassning än med autentisering. De respondenterna med hög tillit tenderar att vara villiga att ge ut mer privat information än de med låg tillit. En majoritet är också positivt inställda till att lämna ut mer information för ökad bekvämlighet samt att enheterna använder lagrad information för ökad bekvämlighet.

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