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  • Presentation: 2019-09-13 10:15 K3, Kåkenhus, Norrköping
    Liu, Yu
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik, elektroteknik och matematik. Linköpings universitet, Tekniska fakulteten.
    A Data-centric Internet of Things Framework Based on Public Cloud2019Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The pervasive application of Internet of Things (IoT) has been seen in many aspects in human daily life and industrial production. The concept of IoT originates from traditional machine-to-machine (M2M) communications which aimed at solving domain-specific and applicationspecific problems. Today, the rapid progress of communication technologies, the maturation of Internet infrastructures, the continuously reduced cost of sensors, and emergence of more open standards, have witnessed the approaching of the expected IoT era, which envisions full connectivity between the physical world and the digital world via the Internet protocol. The popularity of cloud computing technology has enhanced this IoT transform, benefiting from the superior computing capability and flexible data storage, let alone the security, reliability and scalability advantages.

    However, there are still a series of obstacles confronted by the industry in deployment of IoT services. First, due to the heterogeneity of hardware devices and application scenarios, the interoperability and compatibility between link-layer protocols, sub-systems and back-end services are significantly challenging. Second, the device management requires a uniform scheme to implement the commissioning, communication, authorization and identity management to guarantee security. Last, the heterogeneity of data format, speed and storage mechanism for different services pose a challenge to further data mining.

    This thesis aims to solve these aforementioned challenges by proposing a data-centric IoT framework based on public cloud platforms. It targets at providing a universal architecture to facilitate the deployment of IoT services in massive IoT and broadband IoT categories. The framework involves three representative communication protocols, namely WiFi, Thread and Lo-RaWAN, to enable support for local, personal, and wide area networks. A security assessment taxonomy for wireless communications in building automation networks is proposed as a tool to evaluate the security performance of adopted protocols, so as to mitigate potential network flaws and guarantee the security. Azure cloud platform is adopted in the framework to provide device management, data processing and storage, visualization, and intelligent services, thanks to the mature cloud infrastructure and the uniform device model and data model. We also exhibit the value of the study by applying the framework into the digitalization procedure of the green plant wall industry. Based on the framework, a remote monitoring and management system for green plant wall is developed as a showcase to validate the feasibility. Furthermore, three specialized visualization methods are proposed and a neuron network-based anomaly detection method is deployed in the project, showing the potential of the framework in terms of data analytics and intelligence.

    1. A Data-Centric Internet of Things Framework Based on Azure Cloud
    Öppna denna publikation i ny flik eller fönster >>A Data-Centric Internet of Things Framework Based on Azure Cloud
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    2019 (Engelska)Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 7, s. 53839-53858Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Internet of Things (IoT) has been found pervasive use cases and become a driving force to constitute a digital society. The ultimate goal of IoT is data and the intelligence generated from data. With the progress in public cloud computing technologies, more and more data can be stored, processed and analyzed in cloud to release the power of IoT. However, due to the heterogeneity of hardware and communication protocols in the IoT world, the interoperability and compatibility among different link layer protocols, sub-systems, and back-end services have become a significant challenge to IoT practices. This challenge cannot be addressed by public cloud suppliers since their efforts are mainly put into software and platform services but can hardly be extended to end devices. In this paper, we propose a data-centric IoT framework that incorporates three promising protocols with fundamental security schemes, i.e., WiFi, Thread, and LoRaWAN, to cater to massive IoT and broadband IoT use cases in local, personal, and wide area networks. By taking advantages of the Azure cloud infrastructure, the framework features a unified device management model and data model to conquer the interoperability challenge. We also provide implementation and a case study to validate the framework for practical applications.

    Ort, förlag, år, upplaga, sidor
    IEEE, 2019
    Internet of Things, Cloud computing, Protocols, Wireless fidelity, Broadband communication, Monitoring, Interoperability, framework, cloud, azure, IoT hub, thread, WiFi, lorawan
    Nationell ämneskategori
    Data- och informationsvetenskap
    urn:nbn:se:liu:diva-156704 (URN)10.1109/ACCESS.2019.2913224 (DOI)000467047300001 ()

    Funding agencies:  Swedish Environmental Protection Agency; Norrkoping Fund for Research and Development, Sweden

    Tillgänglig från: 2019-05-10 Skapad: 2019-05-10 Senast uppdaterad: 2019-08-21
    2. A Taxonomy for the Security Assessment of IP-based Building Automation Systems: The Case of Thread
    Öppna denna publikation i ny flik eller fönster >>A Taxonomy for the Security Assessment of IP-based Building Automation Systems: The Case of Thread
    2018 (Engelska)Ingår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 14, nr 9, s. 4113-4123Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Motivated by the proliferation of wireless building automation systems (BAS) and increasing security-awareness among BAS operators, in this paper we propose a taxonomy for the security assessment of BASs. We apply the proposed taxonomy to Thread, an emerging native IP-based protocol for BAS. Our analysis reveals a number of potential weaknesses in the design of Thread. We propose potential solutions for mitigating several identified weaknesses and discuss their efficacy. We also provide suggestions for improvements in future versions of the standard. Overall, our analysis shows that Thread has a well-designed security control for the targeted use case, making it a promising candidate for communication in next generation BASs.

    Nationell ämneskategori
    Elektroteknik och elektronik
    urn:nbn:se:liu:diva-148570 (URN)10.1109/TII.2018.2844955 (DOI)000443994500032 ()

    Funding agencies: Vinnova (Swedish Innovation Agency); Norrkoping Fund for Research and Development in Sweden; Swedish Civil Contingencies Agency (MSB) through the Cerces project

    Tillgänglig från: 2018-06-13 Skapad: 2018-06-13 Senast uppdaterad: 2019-08-21
    3. Active Plant Wall for Green Indoor Climate Based on Cloud and Internet of Things
    Öppna denna publikation i ny flik eller fönster >>Active Plant Wall for Green Indoor Climate Based on Cloud and Internet of Things
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    2018 (Engelska)Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 6, s. 33631-33644Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    An indoor climate is closely related to human health, well-being and comfort. Thus, indoor climate monitoring and management are prevalent in many places, from public offices to residential houses. Our previous research has shown that an active plant wall system can effectively reduce the concentrations of particulate matter and volatile organic compounds and stabilize the carbon dioxide concentration in an indoor environment. However, regular plant care is restricted by geography and can be costly in terms of time and money, which poses a significant challenge to the widespread deployment of plant walls. In this article, we propose a remote monitoring and control system that is specific to the plant walls. The system utilizes the Internet of Things technology and the Azure public cloud platform to automate the management procedure, improve the scalability, enhance user experiences of plant walls, and contribute to a green indoor climate.

    Ort, förlag, år, upplaga, sidor
    IEEE, 2018
    Nationell ämneskategori
    Data- och informationsvetenskap
    urn:nbn:se:liu:diva-148850 (URN)10.1109/ACCESS.2018.2847440 (DOI)
    Tillgänglig från: 2018-06-20 Skapad: 2018-06-20 Senast uppdaterad: 2019-08-21
    4. A Study on Visual Representations for Active Plant Wall Data Analysis
    Öppna denna publikation i ny flik eller fönster >>A Study on Visual Representations for Active Plant Wall Data Analysis
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    2019 (Engelska)Ingår i: DATA, E-ISSN 2306-5729, Vol. 4, nr 2, artikel-id 74Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The indoor climate is closely related to human health, well-being, and comfort. Thus, an understanding of the indoor climate is vital. One way to improve the indoor climates is to place an aesthetically pleasing active plant wall in the environment. By collecting data using sensors placed in and around the plant wall both the indoor climate and the status of the plant wall can be monitored and analyzed. This manuscript presents a user study with domain experts in this field with a focus on the representation of such data. The experts explored this data with a Line graph, a Horizon graph, and a Stacked area graph to better understand the status of the active plant wall and the indoor climate. Qualitative measures were collected with Think-aloud protocol and semi-structured interviews. The study resulted in four categories of analysis tasks: Overview, Detail, Perception, and Complexity. The Line graph was found to be preferred for use in providing an overview, and the Horizon graph for detailed analysis, revealing patterns and showing discernible trends, while the Stacked area graph was generally not preferred. Based on these findings, directions for future research are discussed and formulated. The results and future directions of this research can facilitate the analysis of multivariate temporal data, both for domain users and visualization researchers.

    Ort, förlag, år, upplaga, sidor
    MDPI, 2019
    visualization; qualitative evaluation; temporal multivariate data; active plant walls, Visualisering; kvalitativ utvärdering; tidsvarierande multivariate data; active plant walls
    Nationell ämneskategori
    Data- och informationsvetenskap
    urn:nbn:se:liu:diva-157027 (URN)10.3390/data4020074 (DOI)000475303500028 ()
    Tillgänglig från: 2019-05-23 Skapad: 2019-05-23 Senast uppdaterad: 2019-08-21Bibliografiskt granskad
  • Presentation: 2019-09-27 10:15 Alan Turing, Linköping
    Mengist, Alachew
    Linköpings universitet, Institutionen för datavetenskap, Programvara och system.
    Methods and Tools for Efficient Model-Based Development of Cyber-Physical Systems with Emphasis on Model and Tool Integration2019Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Model-based tools and methods are playing important roles in the design and analysis of cyber-physical systems before building and testing physical prototypes. The development of increasingly complex CPSs requires the use of multiple tools for different phases of the development lifecycle, which in turn depends on the ability of the supporting tools to interoperate. However, currently no vendor provides comprehensive end-to-end systems engineering tool support across the entire product lifecycle, and no mature solution currently exists for integrating different system modeling and simulation languages, tools and algorithms in the CPSs design process. Thus, modeling and simulation tools are still used separately in industry.

    The unique challenges in integration of CPSs are a result of the increasing heterogeneity of components and their interactions, increasing size of systems, and essential design requirements from various stakeholders. The corresponding system development involves several specialists in different domains, often using different modeling languages and tools. In order to address the challenges of CPSs and facilitate design of system architecture and design integration of different models, significant progress needs to be made towards model-based integration of multiple design tools, languages, and algorithms into a single integrated modeling and simulation environment.

    In this thesis we present the need for methods and tools with the aim of developing techniques for numerically stable co-simulation, advanced simulation model analysis, simulation-based optimization, and traceability capability, and making them more accessible to the model-based cyber physical product development process, leading to more efficient simulation. In particular, the contributions of this thesis are as follows: 1) development of a model-based dynamic optimization approach by integrating optimization into the model development process; 2) development of a graphical co-modeling editor and co-simulation framework for modeling, connecting, and unified system simulation of several different modeling tools using the TLM technique; 3) development of a tool-supported method for multidisciplinary collaborative modeling and traceability support throughout the development process for CPSs; 4) development of an advanced simulation modeling analysis tool for more efficient simulation.