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  • 1.
    Al-Dulaimy, Auday
    et al.
    Dalarna University, School of Information and Engineering, Informatics. Mälardalen University.
    Ashjaei, M.
    Behnam, M.
    Nolte, T.
    Papadopoulos, A. V.
    Fault Tolerance in Cloud Manufacturing: An Overview2023In: Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST, Springer Science and Business Media Deutschland GmbH , 2023, p. 89-101Conference paper (Refereed)
    Abstract [en]

    Utilizing edge and cloud computing to empower the profitability of manufacturing is drastically increasing in modern industries. As a result of that, several challenges have raised over the years that essentially require urgent attention. Among these, coping with different faults in edge and cloud computing and recovering from permanent and temporary faults became prominent issues to be solved. In this paper, we focus on the challenges of applying fault tolerance techniques on edge and cloud computing in the context of manufacturing and we investigate the current state of the proposed approaches by categorizing them into several groups. Moreover, we identify critical gaps in the research domain as open research directions. © 2023, ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.

  • 2.
    Andersson, Jens
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Berg, Marcus
    Dalarna University, School of Information and Engineering, Information Systems.
    Klassificering av refuger baserat på spatiala vektorpolygoner i vägnät: En fallstudie om utmaningar och lösningar till att klassificera företeelser till det norska vägnätet2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Geographical information systems are becoming increasingly important in today´s society where spatial data can be stored, collected, analysed, and visualized. By compiling spatial data reality can be abstracted. Detailed information on road networks and objects (traffic islands, noise barriers, signs, etcetera) for analysis leads to more efficient operation and maintenance work. Which in turn provides increased accessibility for road users. The technology company Triona has a map application where algorithmic connection of traffic islands (Norway-dataset) to the Norwegian road network has been challenging. A traffic island is an elevation in the street that delimits lanes and is reminiscent of a sidewalk in appearance. This case study addressed a sub-problem where classification of traffic islands could facilitate the connection and prerequisites for analysis. The aim was to present methods that could classify the traffic islands with supervised machine learning. With the algorithms K-nearest neighbors (KNN) and Decision tree, the possibility of automatically classifying the traffic islands was studied. A traffic island consisted of a vector polygon which is a list storing its corners (latitude and longitude). The Norway-dataset was not previously labelled into its eleven types. A data collection of 2157 refuges with seven types from Portland, USA was therefore applied instead. The traffic islands were transformed with Elliptical Fourier Descriptors which extracted an approximation of its contours to train the machine learning models on. Conclusions could be drawn by analysing the contours and observing performance. Performance was evaluated based on accuracy with precision and recall on the Port-land-dataset. Accuracy is the proportion of correct classifications. KNN achieved 64% and Decision Tree 69% accuracy. As both datasets contained real traffic islands in road networks, an assumption could be made that the accuracy would not be much higher if applied on the Norway-dataset. The result was not considered sufficient for a recommendation.

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  • 3.
    Andersson, Mattias
    et al.
    Dalarna University, School of Information and Engineering, Informatics.
    Marshall Olsson, Tom
    Dalarna University, School of Information and Engineering, Informatics.
    ChatGPT as a Supporting Tool for System Developers: Understanding User Adoption2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: AI, specifically conversational AI like OpenAI's ChatGPT, is rapidly expanding in personal and professional settings, offering cost-cutting and modernization opportunities for businesses. This technology, capable of simulating human-like conversations, holds promise across various industries, potentially enhancing productivity through human-AI collaboration. The main research problem is to identify factors influencing system developers' adoption of ChatGPT, considering its design and implementation to mitigate potential negative impacts. Aim: This study aims to investigate the factors that influence user adoption of ChatGPT as a tool to support system developers. Additionally, it aims to identify how ChatGPT can aid system developers in their daily work, and challenges associated with incorporating ChatGPT in this context. Method: Using a case study approach with qualitative and quantitative data collection methods, the study employs positivist and interpretivist philosophical paradigms. Results: Results showed that the perceived ability of ChatGPT to enhance efficiency and generate accurate responses significantly impacts adoption intentions. When examining aspects related to timesaving, productivity enhancement, and user-friendliness, no statistically significant results were found. Among developers, ChatGPT is considered valuable for simplifying tasks and assisting junior developers. There are concerns regarding its capability to handle complex tasks and potential security issues. Suggestions for improvement include better integration with integrated development environments (IDEs) and enhanced accuracy. Conclusions: The findings highlight perceived accuracy and efficiency as driving factors for user adoption regarding ChatGPT. ChatGPT can support tasks like debugging, code generation, code refactoring, code optimization, and technical documentation. However, there may be some potential limitations when dealing with overly complex code. Barriers to adoption include concerns about integrity and security, lack of awareness, and functional limitations. Implications: The insights gained can indirectly benefit companies, including our business partner CGI, by guiding decision-making processes related to the effective adoption and utilization of ChatGPT.

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  • 4.
    Barraza, Diego
    Dalarna University, School of Information and Engineering, Information Systems.
    Behov av systemintegration i energibranschen: En fallstudie om hur ett behov uppstår.2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The case study has examined how a need arises to integrate information systems with each other, what it means for companies that do not choose to integrate information systems and what advantages and disadvantages there are with system integration. The case company which in this study is called “Energiföretaget AB” and has several areas of responsibility that are considered to be socially important services for the infrastructure. The company provides locals with energy, drinking water, waste management and heat. Based on the business' seven different areas of responsibility, the case company is forced to use several information systems that provide the business system with all the necessary data for the staff to be able to create and connect with customers. The data collection was carried out via semi-structured interviews and three different people were interviewed from the case company. The selection of respondents is based on various criteria that were considered necessary for the study. The analysis has been able to reflect the study's theories that present four different types of information systems that companies can use and seven different motives for system integrations. The result of the study is that the need for system integration can consist of the outside world's demands on the business, where political decisions also affect whether the information systems must be changed and integrated with other information systems. The case company's latest expansion of area of responsibility also affects information systems in the business to be able to meet the work processes' needs. This means that changes are taking place and existing information systems must be integrated. It answers the first research question in this study. The second research question, which is what it means for companies that do not choose to integrate information systems, has not been answered due to the insufficient data collected and cannot be generalized. The third research question, which are the advantages and disadvantages of system integrations, has been answered and summarized in a table. Based on the analysis, the respondents' answers have been summarized in the table and report several points in both advantages and disadvantages. A recurring point that the respondents mentioned was that manual work disappears and minimizes errors in the information systems.

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  • 5.
    Bruckner, Fanny
    et al.
    Dalarna University, School of Information and Engineering, Informatics.
    Njie, Isac
    Dalarna University, School of Information and Engineering, Informatics.
    Handling Third-Party Component Licenses:A Case Study in a Swedish Company: How well do existing license management tools detect potentially unsafe third-party component licenses?2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Modern software development relies heavily on third-party components, which are pre-built software modules developed by other organisations and can be either open-source or commercial. These components serve as building blocks for developers to create complex applications more efficiently. What many do not know or realise is that all these third-party components come with licenses that might restrict the software, and it can become a challenge for companies that develop software to manage all the licenses that come with the used third-party components.This thesis investigates three third-party component license management tools: OWASP Dependency-Check, Snyk, and Debricked. The research question was:“How well can the three chosen third-party component license management tools, OWASP Dependency-Check, Snyk and Debricked detect potentially unsafe licenses within software projects?” To answer this question, controlled experiments were conducted to compare the functionality of these tools in two different projects: one advanced project, and one simple project. A comprehensive literature review was conducted to identify the lack of previous research, this provided a theoretical background for the study. The results of the controlled experiments proved that the three chosen tools can help developers in different ways as they satisfy different needs. For users looking to manage their dependencies, OWASP Dependency-Checkis a preferable option. Debricked has demonstrated its ability to detect potentially unsafe licenses in software projects and offers identification of license families. This feature can be valuable to developers as it simplifies the comprehension of the project’s licenses. Snyk, on the other hand, provided warnings about risks associated with licenses. While Debricked out-performed Snyk in license detection, Snyk still proved to be useful in identifying potentially unsafe licenses in software projects, specifically in this case. The findings of this thesis can benefit software developers, project managers, and organisations that rely on third-party components for their software development. The results of this study may be used to guide the selection and use of third-party components and the appropriate license management tools. Overall, this thesis adds to the body of knowledge on managing third-party component licenses and offers practical insights for methods of software development practices.

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  • 6. Chen, Jifu
    et al.
    Mao, Chengying
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics. School of Software and IoT Engineering, Jiangxi University of Finance and Economics, China.
    QoS prediction for web services in cloud environments based on swarm intelligence search2023In: Knowledge-Based Systems, ISSN 0950-7051, E-ISSN 1872-7409, Vol. 259, article id 110081Article in journal (Refereed)
  • 7.
    Garcia Ambrosiani, Carlos
    Dalarna University, School of Information and Engineering, Information Systems.
    En jämförande studie av traineeprogram inom IT-sektorn2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Companies in the IT and Tech sector operates in a market where a high demand for personnel with relevant education and skills exist. The great demand will continue to increase in upcoming years, which leads to high competition when it comes to attracting people to the company. In this survey, four companies were interviewed with the aim to answer the following research questions: 1. What is the purpose of running a trainee programme, and what values does a trainee programme generate? 2. What are the difficulties in running a trainee programme? To answer the research questions, a qualitative approach has been chosen where the data collection has taken place through semi-structured interviews. The survey shows that an investment in a trainee programme contributes to the supply of skills, at the same time as it positively affects the culture within an organization. A challenge that several companies experience is how to get trainees to stay at the company for a long time. In addition to this, the challenges are of a varying nature, much depending on the variation of length of the trainee programmes.

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  • 8.
    Ghaderi, Simko
    Dalarna University, School of Information and Engineering, Informatics.
    En utvärdering av kvalitetssystemet Medrave som används av hälso- och sjukvården i Region Dalarna2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    How do we become better at saving lives? How do we improve the quality of the encounters with our patients? Quality systems in the healthcare are functioned and designed to answer the above-mentioned questions. They include tools that allow the user to perform analysis on patients’ data to improve the quality of care. One does this, by looking for patterns in the data that results in negative outcomes. In the year of 2019, Region Dalarna implemented a quality system named Medrave M4. Since then, an evaluation on the use of this quality system within this region has yet not been done. As a way of getting new perspectives on the benefits and cons of quality systems in the healthcare, this thesis chose to evaluate the use of Medrave M4in Region Dalarna. The purpose was to find out what the strengths, weaknesses, opportunities, and threats were with the system. And to determine if the quality of care has improved since Region Dalarna implemented the system. The study's questions have been answered by reviewing previous research, analysing collected data, interviewing relevant people, and observing the Medrave quality system. These parameters have been compared and have been analysed to answer the questions in depth. By analysing the collected data from these sources, the results are that the benefits of utilizing quality systems in the healthcare are diverse and many. The primary care of Region Dalarna managed the vaccinations of Covid–19 much better because of the quality system. It allowed them to easily identify patients in most need of the vaccinations. The quality system has also allowed comparison of results with other organisations. It also supports research and made it possible to reduce unnecessary prescription of medicine to the patients. The disadvantages of using the system are that there is a risk of patient data being leaked. The study also showed that the quality system did not interact optimally with other systems, which can make the work for the staff more difficult. It has also been seen that there is a lack of knowledge within the staff regarding the benefits of the quality system, this in turn can lead to the business unnecessarily abolishing the system.

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  • 9.
    Hellström, Robin
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Jakobsson, Adrian
    Dalarna University, School of Information and Engineering, Information Systems.
    Thiman, David
    Dalarna University, School of Information and Engineering, Information Systems.
    A Comparative Analysis of Three Types of Facial Recognition Models in OpenCV: Utilising normalised and non-normalised training data2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Today, many offices are implementing smart solutions, including cloud services and the Internet of Things. One piece of technology many have found interesting is the use of facial recognition. Deciding which approach to choose to tackle this is unclear. Aim: The aim is to find what implementation and what configuration of that implementation yields the highest accuracy and speed. Method: Two sets of training data were generated. The first set were images of the subjects taken in a non-normalised manner and the second set were images taken in a normalised manner. After training the models, we had the subjects walk past the camera one by one and compared the number of true positive predictions compared to the total amount of frames the subject appeared in, as well as compared the delay between the frames. Results: On non-normalised training data, both Eigenface and Fisherface saw a drop in accuracy when the number of training images increased, LBPH instead saw an increase in accuracy with the same training. No humanly perceptible difference in delay was seen in any model. On normalised data, Eigenface again saw a drop in accuracy, but was now instead joined by LBPH. Fisherface initially performed well in one trained image, performed worse in two training images, and then reached its highest performance on five training images. Conclusions: When implementing face recognition in a limited environment, using models based on LBPH is preferable and will yield the highest prediction accuracy. Implications: The presented research is to be seen as a roadmap or subject to research further on when companies seek to implement face recognition.

  • 10.
    Hopkins, Viktor
    Dalarna University, School of Information and Engineering, Informatics.
    Comparison and evaluation of time series forecasting models and their application in beauty retailing2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The beauty industry has shown steady growth within the last decade and as more retailers move their product selections online, a lot of sales data can be generated. To improve sales and to meet the ever-increasing competition in the beauty retail sector, time series forecasting has potential in providing knowledge and guidelines in decision making to improve business performance. Time series forecasting, or extrapolation of time series data, is the process of fitting a model on historic data and using it to predict future values. The purpose of this thesis is to compare and evaluate multiple established time series forecasting models to find the most accurate model. The models that were selected as candidates for times series forecasting were chosen based on a literature review of scientific articles. Based on the literature review, SARIMA, Prophet, and LSTM were chosen as forecasting models. Following a research strategy of experiments, the chosen models were implemented at a specific representative company of beauty retailers in the Nordic countries, Lyko. The results showed that there was no model that performed the best in every case. It is possible to forecast the sales of beauty products at least somewhat confidently with the given models. By using forecasting models and accounting for the forecasting error, beauty companies can have a solid basis for business decisions and gain a competitive edge in the beauty market. The main takeaway from this thesis is that there is no one-fits-all model. Instead, if possible, all models should be tested on the data to see which model performs the best. The information of this thesis is useful for the decision maker of a beauty retailer when it comes to applications of forecasting algorithms. A model could be chosen based on the specific demands of the business based on accuracy, runtime, or complexity.

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  • 11.
    Kabel, Tommy
    Dalarna University, School of Information and Engineering, Information Systems.
    Informationsdesign och dess principer: Kartläggning och undersökning av information kring progression och förkunskaper i enlighet med informationsdesign och dess principer.2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When communicating information then it is important to communicate clarity in the message. In order not to confuse the information for the recipient. Information design has several principles to avoid this problem. If an information designer uses the principles correctly, the information designer can communicate clarity in his message. The progression of an education can be an important part o fachieving one's degree goals as a student and therefore it is important if the information about the progression is clear. This study will present principles in information design, principles that help functional, aesthetic,and cognitive properties in information design. The mapping in this study will take the help of the functional principles as they show how to promote a good information design in terms of structure, clarity, simplicity, unity, and emphasis. Gestalt laws and gestalt psychology will also be included because both information design and gestalt psychology deal with the human ability to perceive information, design, and objects in the human environment. The method for the study is to perform a qualitative content analysis of colleges and universities and the programs in accordance with the functional principles of information design. The results show that most of the schools follow the functional principles of information design and there are also cases of additions to the information in the form of figures / basics from the figures. Even though most schools use the functional principles of information design, it was perceived as a challenge to find sources that address the importance of progression in education.

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  • 12.
    Lagin, Madelen
    et al.
    Dalarna University, School of Culture and Society, Business Administration and Management.
    Håkansson, Johan
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Nordström, Carin
    Dalarna University, School of Information and Engineering, Entrepreneurship and Innovation.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Öberg, Christina
    CTF, Service Research Center, Karlstad University; Ratio Institute, Stockholm.
    Last-mile logistics of perishable products: a review of effectiveness and efficiency measures used in empirical research2022In: International Journal of Retail & Distribution Management, ISSN 0959-0552, E-ISSN 1758-6690, Vol. 50, no 13, p. 116-139Article in journal (Refereed)
    Abstract [en]

    Purpose

    Current online business development redistributes last-mile logistics (LML) from consumer to retailer and producer. This paper identifies how empirical LML research has used and defined logistic performance measures for key grocery industry actors. Using a multi-actor perspective on logistic performance, the authors discuss coordination issues important for optimising LML at system level.

    Design/methodology/approach

    A semi-systematic literature review of 85 publications was conducted to analyse performance measurements used for effectiveness and efficiency, and for which actors.

    Findings

    Few empirical LML studies exist examining coordination between key actors or on system level. Most studies focus on logistic performance measurements for retailers and/or consumers, not producers. Key goals and resource utilisations lack research, including all key actors and system-level coordination.

    Research limitations/implications

    Current LML performance research implies a risk for sub-optimisation. Through expanding on efficiency and effectiveness interplay at system level and introducing new research perspectives, the review highlights the need to revaluate single-actor, single-measurement studies.

    Practical implications

    No established scientific guidelines exist for solving LML optimisation in the grocery industry. For managers, it is important to thoroughly consider efficiency and effectiveness in LML execution, coordination and collaboration among key actors, avoiding sub-optimisations for business and sustainability.

    Originality/value

    The study contributes to current knowledge by reviewing empirical research on LML performance in the grocery sector, showing how previous research disregards the importance of multiple actors and coordination of actors, efficiency and effectiveness.

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  • 13.
    Liljegräs, Pontus
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Johansson, Amanda
    Dalarna University, School of Information and Engineering, Information Systems.
    Carlerud Holvall, Sanna
    Dalarna University, School of Information and Engineering, Information Systems.
    Pandemins påverkan på IT-konsulter: En studie om IT-konsulters upplevelse kring distansarbete2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: In 2019, the world was hit by a pandemic named Covid-19. This has led to millions of employees in the EU and around the world being allowed to work from home. Two companies that switched to remote work are Sogeti and CGI. These companies are consulting companies in IT, engineering, and business. Aim: The purpose of this study is to explore how consultants at the companies Sogeti and CGI experience the changed working conditions that have arisen in connection with Covid-19 and to compare the consultants' experiences with previous research. Implementation & strategy: The strategy for this study is to conduct an interview study. The study will be conducted using a qualitative method. The qualitative method includes interviews with selected respondents. Results: The interview results show that 13 out of 16 respondents experienced a smooth transition to remote work and all 16 respondents experience that the remote work has worked well. All respondents experience increased or equivalent individual productivity during teleworking. The results show that 13 of the 16 respondents had a good physical work environment at home, the respondents who lacked certain equipment in the home during the transition to remote work received adequate help from employers or customers to supplement what was missing. Conclusions: The conclusion as to why the consultants' productivity may have increased when they worked remotely is that they have been able to work in an environment with fewer distractions and thus found it easier to stay focused for longer periods. The experience regarding remote work has varied depending on the position of the consultant in the company. The conclusions that can be drawn from the study are that both the managerial role and the project manager role require more physical interaction.

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  • 14.
    Lillieström, Hugo
    Dalarna University, School of Information and Engineering, Informatics.
    Konsumenters preferenser till enkla kontra komplexa logotyper2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Logo changes have become increasingly common, and the logos themselves are becoming simpler. How do consumers perceive this transformation? Aim: The purpose of this study is to examine how the complexity and recognizability of logos can influence consumer preferences. Method: The collection of data was conducted using a web survey distributed via Facebook, resulting in a response rate of 134 participants. The survey employed a choice experiment, where respondents were presented with two response options and asked to select their preferred alternative. In the second part, participants also indicated whether they recognized the logos or not. Results: The results were compiled into frequency tables and analyzed using logistic binomial regression analysis. However, no statistically significant results were obtained. Conclusions: The study does not provide statistical evidence regarding the extent to which the complexity of logos and consumers' recognition of a logo influence consumer preferences. However, in specific cases, there is evidence that individuals who recognizea logo prefer the complex (old) one, while individuals who do not recognize a logo prefer the simple (new) one.

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  • 15.
    Lindgren, Charlie
    et al.
    Dalarna University, School of Information and Engineering, Informatics.
    Li, Yujiao
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Rudholm, Niklas
    Institute of Retail Economics, Stockholm, Sweden.
    Why do firms compete on price comparison websites? The impact on productivity, profits, and wages2022In: International Review of Retail Distribution & Consumer Research, ISSN 0959-3969, E-ISSN 1466-4402, p. 1-13Article in journal (Refereed)
    Abstract [en]

    A substantial literature indicates that competition on price comparison websites is fierce, leading to lower prices for products sold. As such, we want to answer the key research question: Why do firms compete on price comparison websites? Based on theory, we suggest that participation in these marketplaces leads to increased productivity, i.e., output increases when holding constant the level of inputs used. This, in turn, leads to increased profits, motivating firms to enter price comparison websites despite fierce competition. To find out if theory holds, we empirically investigate how firm entry into a price comparison website affects firm productivity, profits, and wages. Empirically investigating the impact of PriceSpy market participation on productivity, profits, and wages is not easy since firms are free to select whether and when to enter or exit the PriceSpy marketplace, and we use a two-step procedure to address this problem. In the first step, we control for differences in observables between entering firms and potential control-group firms. Then, in a second step, we use a within-firm difference-in-difference estimator on the matched data to investigate how entry into the PriceSpy marketplace affects output while holding inputs constant. Our results indicate that for the full sample of firms, PriceSpy participation increases output by almost 12% when holding the level of inputs constant. Also, an investigation of who gains from the increased productivity shows that, for entering firms, operating profits increase by 9% and gross wages by 14% when studying the full sample of firms. That labor gains more from PriceSpy participation is even clearer when studying the impact on wholesale and retail firms separately. For those firms, wages increased by 16–17% after entry, while no statistically significant impact was found regarding operating profits.

  • 16.
    Lyttbacka Kling, Victor
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Lindström, Emma
    Dalarna University, School of Information and Engineering, Information Systems.
    1177 med digitala hjälpmedel för syn-nedsättningar: Hur väl förberedd är 1177 för användare med digitala hjälpmedel2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Public services such as 1177 have, via the Swedish law “Lagen om tillgänglighet till digital offentlig service”, a requirement to ensure accessibility of the service to everyone in Sweden. But how well does a service like 1177 work for a group with severe visual impairments and the need to use digital tools to be able to use 1177? This paper wants to examine it with these two questions: What point of views do they with visual impairments have of 1177? and How do their experiences compare to the requirements from the law Lagen om tillgänglighet till digital offentlig service? via a case study. Method: Data were collected via qualitative interviews and user tests. In the test, several scenarios were designed around the legal requirements and some of Jakob Nilsen’s 10 usability heuristics for the design of user interfaces. Data was also collected from the Swedish Ägency for Digital Ädministration, then in the form of complaints from users of 1177. Results: The result of the work is that 1177 is a well functioning service when it comes to normal use of the service. For example, see booked times or messages, but where the problems start is when the users start to look for or use a function they do not normally use. The problem when looking for a function can be that it is not obvious where it is and that there is no search function. But the most common problem is when signing in on a computer with mobile BankID, you must scan a QR code and that is very problematic when the user is visually impaired. Conclusions: 1177 is a good service in large but it has its problems. Some of the problems can be solved by a search function and others can be solved by letting the users decide what information to be shown.

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  • 17.
    Mehks, Alexander
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Lager, Tobias
    Dalarna University, School of Information and Engineering, Information Systems.
    Effective Internal Communication with Digital Channels: A case study in Sweden2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Much has happened in information technology in the last decade, and the amount of information someone can be exposed to is enormous. There are many digital information channels today used at different organizations. This research study has investigated which channel is used the most, and if there are any methods for handling the flow of information. With these tools and methods, together with a sufficient literature review a proposed model was developed to aid organizations with their information flow. Aim: To conduct research in the field of internal communication with focus on digital channels, to finally come up with what tools and methods can be used for improved internal communication, and to propose a model for this. Method: Three sources of data collections have been used. The first one is semi-structured interviews, where six volunteers have participated, the age ranging from 31-60. The targeted volunteers were the managers, and the employees of the organizations. The second is surveys where 14 volunteers contributed, where we used snowball sampling. The third is a document study that consists of research-generated literature review. Results/Conclusion: Our analysis concluded that the most useful tools for communicating with digital channel sare, namely, email, intranet and telephone. However, the usefulness of the tools decline rapidly when too much unnecessary information flows in the wrong channels. What this research study came up with regarding contribution was an easy to use four step model to be able to classify the information and use the correct channel for it. Working alongside this model, will help with minimizing information overload in the channels used for communication. It is also important from an organization perspective when onboarding employees to learn which channels are used for which kind of information.

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  • 18.
    Mehmeti, Donika
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Palmblad, Linus
    Dalarna University, School of Information and Engineering, Information Systems.
    Application Programming Interfaces: An exploration of their properties and what to consider during implementation2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this study, the focus is on facilitating the API discovery process for developers and organizations. According to research articles, APIs are discussed in this research as the fundamental areas that are considered significant when developers or organizations explore an API. The areas include usability, documentation, stability, collaborative communities, and the popularity of an API. We created a design and creation research process and listed key aspects of each mentioned area above in a final artifact, where the idea is to allow people to look at the artifact and use it in a possible API exploration. In conclusion, the artifact covers usability, documentation, stability, and collaborative communities. There are leading questions in the artifact to determine whether or not an API is suitable for a given purpose.

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  • 19.
    Paidi, Vijay
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Fleyeh, Hasan
    Dalarna University, School of Information and Engineering, Computer Engineering.
    Håkansson, Johan
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Tracking Vehicle Cruising in an Open Parking Lot Using Deep Learning and Kalman Filter2021In: Journal of Advanced Transportation, ISSN 0197-6729, E-ISSN 2042-3195, article id 1812647Article in journal (Refereed)
    Abstract [en]

    Due to the lack of wide availability of parking assisting applications, vehicles tend to cruise more than necessary to find an empty parking space. This problem is evident globally and the intensity of the problem varies based on the demand of parking spaces. It is a well-known hypothesis that the amount of cruising by a vehicle is dependent on the availability of parking spaces. However, the amount of cruising that takes place in search of parking spaces within a parking lot is not researched. This lack of research can be due to privacy and illumination concerns with suitable sensors like visual cameras. The use of thermal cameras offers an alternative to avoid privacy and illumination problems. Therefore, this paper aims to develop and demonstrate a methodology to detect and track the cruising patterns of multiple moving vehicles in an open parking lot. The vehicle is detected using Yolov3, modified Yolo, and custom Yolo deep learning architectures. The detected vehicles are tracked using Kalman filter and the trajectory of multiple vehicles is calculated on an image. The accuracy of modified Yolo achieved a positive detection rate of 91% while custom Yolo and Yolov3 achieved 83% and 75%, respectively. The performance of Kalman filter is dependent on the efficiency of the detector and the utilized Kalman filter facilitates maintaining data association during moving, stationary, and missed detection. Therefore, the use of deep learning algorithms and Kalman filter facilitates detecting and tracking multiple vehicles in an open parking lot.

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  • 20.
    Paidi, Vijay
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Håkansson, Johan
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Fleyeh, Hasan
    Dalarna University, School of Information and Engineering, Computer Engineering.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    CO2 Emissions Induced by Vehicles Cruising for Empty Parking Spaces in an Open Parking Lot2022In: Sustainability, E-ISSN 2071-1050, Vol. 14, no 7, article id 3742Article in journal (Refereed)
    Abstract [en]

    Parking lots are places of high air pollution as numerous vehicles cruise to find vacant parking places. Open parking lots receive high vehicle traffic, and when limited empty spaces are available it leads to problems, such as congestion, pollution, and driver frustration. Due to lack of return on investment, open parking lots are little studied, and there is a research gap in understanding the magnitude of CO2 emissions and cruising observed at open parking lots. Thus, this paper aims to estimate CO2 emissions and cruising distances observed at an open parking lot. A thermal camera was utilized to collect videos during peak and non-peak hours. The resulting videos were utilized to collect cruising trajectories of drivers searching for empty parking spaces. These trajectories were analyzed to identify optimal and non-optimal cruising, time to park, and walking distances of drivers. A new CO2 model was proposed to estimate emissions in smaller geographical regions, such as open parking lots. The majority of drivers tend to choose parking spaces near a shopping center, and they prefer to cruise non-optimal distances to find an empty parking space near the shopping center. The observed mean non-optimal cruising distance is 2.7 times higher than the mean optimal cruising distance. Excess CO2 emissions and non-optimal cruising were mainly observed during visitor peak hours when there were limited or no empty parking spaces. During visitor peak hours, several vehicles could not find an empty parking space in the region of interest, which also leads to excess cruising.

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  • 21.
    Peng, Xiangdong
    et al.
    School of Software and Internet of Things Engineering, Jiangxi University of Finance and Economics, Nanchang, China.
    Shu, Weiwei
    School of Software and Internet of Things Engineering, Jiangxi University of Finance and Economics, Nanchang, China.
    Pan, Congcheng
    School of Software and Internet of Things Engineering, Jiangxi University of Finance and Economics, Nanchang, China.
    Ke, Zejun
    School of Software and Internet of Things Engineering, Jiangxi University of Finance and Economics, Nanchang, China.
    Zhu, Huaqiang
    School of Software and Internet of Things Engineering, Jiangxi University of Finance and Economics, Nanchang, China.
    Zhou, Xiao
    School of Software and Internet of Things Engineering, Jiangxi University of Finance and Economics, Nanchang, China.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    DSCSSA: A Classification Framework for Spatiotemporal Features Extraction of Arrhythmia Based on the Seq2Seq Model With Attention Mechanism2022In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 71, article id 2515112Article in journal (Refereed)
    Abstract [en]

    In the field of arrhythmia classification, classification accuracy has always been a research hotspot. However, the noises of electrocardiogram (ECG) signals, the class imbalance of ECG data, and the complexity of spatiotemporal features of ECG data are all important factors affecting the accuracy of ECG arrhythmias classification. In this article, a novel DSCSSA ECG arrhythmias classification framework is proposed. First, discretewavelet transform (DWT) is used to denoise and reconstruct ECG signals to improve the feature extraction ability of ECG signals.Then, the synthetic minority oversampling technique (SMOTE) oversampling method is used to synthesize a new minority sample ECG signal to reduce the impact of ECG data imbalance on classification. Finally, a convolutional neural network (CNN) and sequence-to-sequence (Seq2Seq) classification model with attention mechanism based on bi directional long short-term memory(Bi-LSTM) as the codec is used for arrhythmias classification, and the model can give corresponding weight according to the importance of heartbeat features and can improve the ability toextract and filter the spatiotemporal features of heartbeats. In the classification of five heartbeat types, including normal beat (N), supraventricular ectopic beat (S), ventricular ectopic beat (V),fusion beat (F), and unknown beat (Q), the proposed method achieved the overall accuracy (OA) value and Macro-F1 score of 99.28% and 95.70%, respectively, in public the Massachusetts Institute of Technology - Boston’s Beth Israel Hospital (MIT-BIH)arrhythmia database. These methods are helpful to improve the effectiveness and clinical reference value of computer-aided ECG automatic classification diagnosis.

  • 22. Peng, Xiangdong
    et al.
    Xiong, Panxia
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    Zhou, Xiao
    Zhu, Huaqiang
    Zhang, Quan
    Lu, Yong
    Zheng, Tengfei
    ECG Signals Classification Method for Wireless Body Area Network Based on Quantized Residual Network2022In: Proceedings of ICBDT, 2022, p. 425-435Conference paper (Refereed)
  • 23.
    Pääkkönen, Joonas
    Dalarna University, School of Information and Engineering, Informatics.
    Predicting Cross-Country Skiing FIS Points with Taper Load Sequences and Neural Networks2022In: IX Mathsport International 2022 Proceedings, 2022, p. 75-83Conference paper (Refereed)
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  • 24.
    Reza, Amed
    et al.
    Dalarna University, School of Information and Engineering, Information Systems.
    Modin, Douglas
    Dalarna University, School of Information and Engineering, Information Systems.
    Fallstudie om strategier för riskminimering vid utrullning av ERP-system2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    ERP systems can be very complex to implement in organizations. This is a challenge that has existed for a long time, where ERP implementations fail to a large extent, partly due to a lack of strategies. Technology is evolving, and thus organizations must keep up with that development when it comes to systems. All organizations are different and therefore require different solutions. This can entail risks and problems during the process to achieve a successful result. This study examines which strategies are useful during the planning phase to minimize risks when rolling out a global ERP system. The purpose is to evaluate strategies and risks in the planning phase where there is a lack of previous research. It is not considered the most important part of system changes but is a very important factor for a successful result. The case study focuses on a global project where the preparation phase of an ERP rollout is in progress. The data collection consists of documents from the organization as well as interviews with four different key persons within the project. The conclusion of the thesis shows that it is crucial to define the strategy of structured processes for managing risks early in the project.

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  • 25.
    Saeed, Nausheen
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Alam, Moudud
    Dalarna University, School of Information and Engineering, Statistics.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    A multimodal deep learning approach for gravel road condition evaluation through image and audio integration2024In: Transportation Engineering, ISSN 2666-691X, Vol. 16, article id 100228Article in journal (Refereed)
    Abstract [en]

    This study investigates the combination of audio and image data to classify road conditions, particularly focusingon loose gravel scenarios. The dataset underwent binary categorisation, comprising audio segments capturinggravel sounds and corresponding images. Early feature fusion, utilising a pre-trained Very Deep ConvolutionalNetworks 19 (VGG19) and Principal component analysis (PCA), improved the accuracy of the Random Forestclassifier, surpassing other models in accuracy, precision, recall, and F1-score. Late fusion, involving decisionlevelprocessing with logical disjunction and conjunction gates (AND and OR) in combination with individualclassifiers for images and audio based on Densely Connected Convolutional Networks 121 (DenseNet121),demonstrated notable performance, especially with the OR gate, achieving 97 % accuracy. The late fusionmethod enhances adaptability by compensating for limitations in one modality with information from the other.Adapting maintenance based on identified road conditions minimises unnecessary environmental impact. Thismethod can help to identify loose gravel on gravel roads, substantially improving road safety and implementing aprecise maintenance strategy through a data-driven approach.

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  • 26.
    Saeed, Nausheen
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Alam, Moudud
    Dalarna University, School of Information and Engineering, Statistics.
    Gravel road classification based on loose gravel using transfer learning2022In: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Road maintenance agencies subjectively assess loose gravel as one of the parameters for determininggravel road conditions. This study aims to evaluate the performance of deep learning-based pretrainednetworks in rating gravel road images according to classical methods as done by humanexperts. The dataset consists of images of gravel roads extracted from self-recorded videos andimages extracted from Google Street View. The images were labelled manually, referring to thestandard images as ground truth defined by the Road Maintenance Agency in Sweden (Trafikverket).The dataset was then partitioned in a ratio of 60:40 for training and testing. Various pre-trainedmodels for computer vision tasks, namely Resnet18, Resnet50, Alexnet, DenseNet121, DenseNet201,and VGG-16, were used in the present study. The last few layers of these models were replaced toaccommodate new image categories for our application. All the models performed well, with anaccuracy of over 92%. The results reveal that the pre-trained VGG-16 with transfer learning exhibitedthe best performance in terms of accuracy and F1-score compared to other proposed models.

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  • 27.
    Saeed, Nausheen
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Alam, Moudud
    Dalarna University, School of Information and Engineering, Statistics.
    Dougherty, Mark
    School of Information Technology, Halmstad University.
    Jomaa, Diala
    Dalarna University, School of Teacher Education, Education.
    Rebreyend, Pascal
    Dalarna University, School of Information and Engineering, Computer Engineering.
    Classification of the Acoustics of Loose Gravel2021In: Sensors, E-ISSN 1424-8220, Vol. 21, no 14, article id 4944Article in journal (Refereed)
    Abstract [en]

    Road condition evaluation is a critical part of gravel road maintenance. One of the assessed parameters is the amount of loose gravel, as this determines the driving quality and safety. Loose gravel can cause tires to slip and the driver to lose control. An expert assesses the road conditions subjectively by looking at images and notes. This method is labor-intensive and subject to error in judgment; therefore, its reliability is questionable. Road management agencies look for automated and objective measurement systems. In this study, acoustic data on gravel hitting the bottom of a car was used. The connection between the acoustics and the condition of loose gravel on gravel roads was assessed. Traditional supervised learning algorithms and convolution neural network (CNN) were applied, and their performances are compared for the classification of loose gravel acoustics. The advantage of using a pre-trained CNN is that it selects relevant features for training. In addition, pre-trained networks offer the advantage of not requiring days of training or colossal training data. In supervised learning, the accuracy of the ensemble bagged tree algorithm for gravel and non-gravel sound classification was found to be 97.5%, whereas, in the case of deep learning, pre-trained network GoogLeNet accuracy was 97.91% for classifying spectrogram images of the gravel sounds.

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    Classification of the Acoustics of Loose Gravel
  • 28.
    Salin, Hannes
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis. Swedish Transport Administration, Borlänge, Sweden.
    Rybarczyk, Yves
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Han, Mengjie
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Nyberg, Roger G
    Dalarna University, School of Information and Engineering, Informatics.
    Quality Metrics for Software Development Management and Decision Making: An Analysis of Attitudes and Decisions2022In: Product-Focused Software Process Improvement. 23rd International Conference, PROFES 2022, Jyväskylä, Finland, November 21–23, 2022, Proceedings / [ed] Taibi, D., Kuhrmann, M., Mikkonen, T., Klünder, J., Abrahamsson, P., Springer, 2022, Vol. 13709, p. 525-530Conference paper (Refereed)
    Abstract [en]

    We combine current literature in software quality metrics with an attitude validation study with industry practitioners, to establish how quality metrics can be used for data-driven approaches. We also propose a simple metric nomenclature and map our findings into a decision making model for easy adoption and utilization of data-driven decision-making methods. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

  • 29.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    An Approximation Computation Approach to Big Data Analysis with a Case Analysis of PV System2023In: 8th International Conference on Cloud Computing and Big Data Analytics, ICCCBDA 2023, Institute of Electrical and Electronics Engineers Inc. , 2023, p. 44-52Conference paper (Refereed)
    Abstract [en]

    In the era of big data, it is indispensable to apply data science and technology for big data analysis to solve the big data problems. With the advancement of the big data technologies, we are also facing many problems when dealing with the big data and their studies. It is obvious that big data become "bigger"and "bigger", more complex than before, with a good number of attributes and features in various formats and styles. On the other hand, many data analysis techniques have been proposed for various application domain problems in different purposes. This worsens the situation of choosing an appropriate method for a right problem of right data. In this paper, the author intends to propose an approximation approach toward this problem, through discussing the ways of identification of patterns of the original data, be they of data features or analysis methods. The author attempts to apply the idea to a case of fault detection of a household photovoltaic system. © 2023 IEEE.

  • 30.
    Song, William Wei
    et al.
    Dalarna University, School of Information and Engineering, Informatics.
    Zhu, Yurong
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Wang, Xiaohuan
    Peng, Xiangdong
    An Investigation into Effective Data Analysis Methods for Sensor Datasets of a Sample Building2022In: Proceedings of ICBDT 2022, 2022, p. 125-130Conference paper (Refereed)
  • 31.
    Sundqvist, Nathalie
    et al.
    Dalarna University, School of Information and Engineering, Informatics.
    Gustafsson, Malin
    Dalarna University, School of Information and Engineering, Informatics.
    Utmaningar vid överlämning av anläggningsdata från projekt till förvaltning: En fallstudie på Trafikverket2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: According tö previous studies, finding effective ways to handle handovers is still important. There is extensive research on project methods, yet not as much attention has been directed to the actual handover process to internal recipients. The Swedish Transport Administration experiences shortcomings in the handover process after completed change projects. The study is carried out in collaboratiön with the Swedish Transport Administration. Aim: The purpose öf this study is to identify challenges experienced in the handover of facility data. The study also evaluates how the organisation´s handover process of facility data meets success factors for handover. Method: The study is a case study where the data collection was carried out through semi-structured interviews and a survey. Initially, a literature study was carried out to select a topic and a further literature study was carried out with the aim identifying success factors in handovers. The results were analyzed by performing a gap analysis. Results: The study results indicate that handovers involve several challenges, and the organization under investigation meets several of the success factors. Challenges identified in the case are: incomplete completion öf templates upon delivery, lack of decision log support systems during ongoing projects, delays due to non-compliance with regulations by the project, delays caused by changes in requirements after procurement, and a lack of standardization and automation in delivery. Success factors met by the organization in the case are: initially conducting stakeholder analysis, initially providing a delivery plan, detailed requirement specification, and early open dialogue between the project and operations. Conclusions: In summary, it can be established that the Swedish Transport Administratiön is aware öf several öf the success factors and that access to  tools via methods and frameworks is available. The desired results are still not achieved often enough to be considered successful handovers. The study's results för how an organization meets success factors are also applicable to other businesses that handle complex handovers of facility data.

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  • 32. Wang, Jing
    et al.
    Ji, Yanfeng
    Wei, Linfeng
    Chen, Hui
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    A dynamic firefly algorithm based on two-way guidance and dimensional mutation2022In: International Journal of Bio-Inspired Computation (IJBIC), ISSN 1758-0366, E-ISSN 1758-0374, Vol. 20, no 2, p. 126-126Article in journal (Refereed)
    Abstract [en]

    As a stochastic optimiser, the firefly algorithm (FA) has been successfully and widely used in the solutions to various optimisation problems. Recent related research shows that the standard FA does not sufficiently balance between exploration and exploitation. Especially in high-dimensional problems, it is easy for the standard FA to fall into the local optimum and lead to premature convergence. To overcome the problems as mentioned above, DMTgFA uses three strategies: dynamic step length setting strategy (DS), non-elite two-way guidance model (TG) and elites dimensional mutation strategy (DM). The dynamic step length setting strategy makes the algorithm convergence speed faster. The non-elite two-way guidance model and the elite dimensional mutation strategy cooperate to solve the balance problem between global search and local search. Experimental results show that DMTgFA has stronger optimisation ability and faster convergence speed than other state-of-the-art FA variants.

  • 33.
    Wang, Mengfei
    et al.
    Dalarna University, School of Information and Engineering, Informatics.
    Shu, Shiqi
    Dalarna University, School of Information and Engineering, Informatics.
    Research of appropriate luminance level of monitor screens in workplace2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    OBJECTIVE: The main goal of this study is to investigate the impact of natural light on the human eye's preference for screen brightness when viewing a computer screen. METHODS: Three experiments are conducted to measure the extent to which sunlight changes the background light in terms of solar radiation. The Pre-experiment takes pictures with a camera that simulates the human eye and a 27" monitor to simulate the background environment. Pre-experiment varied the brightness of the screen and post-screen of a solid color RGB image to obtain the intensity of light entering the human eye under various conditions. Control Experiment increased the luminance interval to 10 and reduced the brightness level to 5 levels from 60-100. We obtained 2000 data on the relationship between sunlight and solar radiation to predict the change in room light when curtains are drawn. Interview tested 16 adults working at Sogeti to obtain their preference for different colors in different background lighting conditions. RESULTS: Pre-experiment and Control Experiment showed that each color has a different effect on the intensity of light emitted by the screen brightness when the ambient light changes. Interview results showed that people have different preferences for brightness. Dark colors require higher screen light intensity when the solar radiation is 0:241, while bright colors require lower screen light intensity when the solar radiation is 430:751. CONCLUSIONS: The most important idea is to maintain a certain ratio of environmental brightness to screen brightness to avoid visual fatigue caused by the screen. This study provides theoretical assistance for electronic device manufacturers and provides reference opinions for adaptive adjustment of different colors and brightness displayed on screens.

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  • 34. Wang, Xiaohuan
    et al.
    Li, Hongping
    Zhu, Yurong
    Peng, Xiangdong
    Wan, Zhibin
    Xu, Huatai
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Information Systems.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Information Systems.
    Fei, Benhua
    Using Machine Learning Method to Discover Hygrothermal Transfer Patterns from the Outside of the Wall to Interior Bamboo and Wood Composite Sheathing2022In: Buildings, E-ISSN 2075-5309, Vol. 12, no 7, p. 898-898Article in journal (Refereed)
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  • 35. Wang, Z.
    et al.
    Qin, C.
    Wan, B.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics. School of Software and IoT Engineering, Jiangxi University of Finance & Economics, Nanchang, China.
    A comparative study of common nature‐inspired algorithms for continuous function optimization2021In: Entropy, E-ISSN 1099-4300, Vol. 23, no 7, article id 874Article in journal (Refereed)
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  • 36. Wang, Zhenwu
    et al.
    Qin, Chao
    Wan, Benting
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics. Jiangxi University of Finance & Economics, Nanchang, China.
    Yang, Guoqiang
    An Adaptive Fuzzy Chicken Swarm Optimization Algorithm2021In: Mathematical problems in engineering (Print), ISSN 1024-123X, E-ISSN 1563-5147, Vol. 2021, article id 8896794Article in journal (Refereed)
    Abstract [en]

    The chicken swarm optimization (CSO) algorithm is a new swarm intelligence optimization (SIO) algorithm and has been widely used in many engineering domains. However, there are two apparent problems with the CSO algorithm, i.e., slow convergence speed and difficult to achieve global optimal solutions. Aiming at attacking these two problems of CSO, in this paper, we propose an adaptive fuzzy chicken swarm optimization (FCSO) algorithm. The proposed FCSO uses the fuzzy system to adaptively adjust the number of chickens and random factors of the CSO algorithm and achieves an optimal balance of exploitation and exploration capabilities of the algorithm. We integrate the cosine function into the FCSO to compute the position update of roosters and improve the convergence speed. We compare the FCSO with eight commonly used, state-of-the-art SIO algorithms in terms of performance in both low- and high-dimensional spaces. We also verify the FCSO algorithm with the nonparametric statistical Friedman test. The results of the experiments on the 30 black-box optimization benchmarking (BBOB) functions demonstrate that our FCSO outperforms the other SIO algorithms in both convergence speed and optimization accuracy. In order to further test the applicability of the FCSO algorithm, we apply it to four typical engineering problems with constraints on the optimization processes. The results show that the FCSO achieves better optimization accuracy over the standard CSO algorithm.

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  • 37.
    Westergren, Jens
    et al.
    Dalarna University, School of Health and Welfare, Sport and Health Science. Dalarna University, School of Health and Welfare, Care Sciences.
    Sjöberg, Veronica
    Dalarna University, School of Health and Welfare, Care Sciences. Dalarna University, School of Health and Welfare, Medical Science.
    Vixner, Linda
    Dalarna University, School of Health and Welfare, Medical Science.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Moulaee Conradsson, David
    Monnier, Andreas
    Dalarna University, School of Health and Welfare, Medical Science. Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Huddinge.
    LoMartire, Riccardo
    Enthoven, Paul
    Äng, Björn
    Dalarna University, School of Health and Welfare, Medical Science. Karolinska Institutet; Center for Clinical Research Dalarna, Uppsala University, Region Dalarna, Falun; Regional Board Administration, Region Dalarna, Falun.
    Acute exercise as active inference in chronic musculoskeletal pain, effects on gait kinematics and muscular activity in patients and healthy participants: a study protocol for a randomised controlled laboratory trial2023In: BMJ Open, E-ISSN 2044-6055, Vol. 13, no 5, article id e069747Article in journal (Refereed)
    Abstract [en]

    Introduction

    Chronic musculoskeletal pain is a highly prevalent, complex and distressing condition that may negatively affect all domains of life. In view of an active inference framework, and resting on the concept of allostasis, human movement per se becomes a prerequisite for health and well-being while chronic pain becomes a sign of a system unable to attenuate an allostatic load. Previous studies on different subgroups of chronic pain conditions have demonstrated alterations in gait kinematics and muscle activity, indicating shared disturbances in the motor system from long-term allostatic load. We hypothesise that such alterations exist in heterogenous populations with chronic musculoskeletal pain, and that exposure to acute and controlled exercise may attenuate these alterations. Therefore, the main aim of this study is to investigate the acute effects of exercise on gait kinematics and activity of the back and neck muscles during diverse walking conditions in patients with chronic musculoskeletal pain compared with a reference sample consisting of healthy participants.

    Methods and analysis

    This two-sample two-armed parallel randomised controlled laboratory trial will include 40 participants with chronic musculoskeletal pain (>3 months) and 40 healthy participants. Participants will be randomly allocated to either 30 min of aerobic exercise or rest. Primary outcomes are gait kinematics (walking speed, step frequency, stride length, lumbar rotation, gait stability) and muscular activity (spatial and temporal) of the back and neck during diverse walking conditions. Secondary outcomes are variability of gait kinematics and muscle activity and subjective pain ratings assessed regularly during the trial.

    Ethics and dissemination

    The study has been approved by the Regional Ethics Review Board in Uppsala, Sweden (#2018/307). Findings will be disseminated via conference presentations, publications in peer-reviewed journals and engagement with patient support groups and clinicians.

    Trial registration number

    NCT03882333.

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    Acute exercise as active inference in chronic musculoskeletal pain, effects on gait kinematics and muscular activity in patients and healthy participants: a study protocol for a randomised controlled laboratory trial
  • 38. Xu, Y.
    et al.
    Wu, G.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    A Predictive Study of ARIMA Model Based on Multi-Bayesian Estimation Method Fused Data on Building Materials Environment2023In: ACM International Conference Proceeding Series, ACM Digital Library, 2023, p. 22-27Conference paper (Refereed)
    Abstract [en]

    Due to the uncertainty and inconsistency of measurement data from multiple sensors in the same space, a multi-sensor data fusion algorithm is used to fuse the measurement data of multiple nodes. We propose a multi-Bayesian estimation method for fusing multi-sensor data, and combine Bayesian estimation with ARIMA model to predict the ambient temperature of bamboo and wood building materials. It can utilize the redundancy of data to reduce this uncertainty and improve the reliability of subsequent predictions. © 2023 ACM.

  • 39. Yu, Z.
    et al.
    Yang, Z.
    Fiedler, Frank
    Dalarna University, School of Information and Engineering, Energy Technology.
    Rao, H.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    Power Generation Prediction of Residential Photovoltaic Equipment Based on Online Transfer Learning Model: A Case Study of a Residential Solar Power System2021In: ACM Int. Conf. Proc. Ser., Association for Computing Machinery , 2021, p. 58-65Conference paper (Refereed)
    Abstract [en]

    Power generation prediction of residential photovoltaic systems has always been a more and more crucial topic when such new types of energy have been widely applied in people's daily life. In this paper, the four seasons are identified more scientifically by studying the variation of solar altitude angles in a year, and hence the meteorological factors hidden in the data collected from a PV system are extracted by clustering and used in the model. Combined with the advantages of the online learning and transfer learning approach, the online transfer learning model is developed to predict power generation. Finally, our experimental results show that the proposed online transfer learning model outperforms the other learning methods. © 2021 ACM.

  • 40. Zhang, S.
    et al.
    Liu, H.
    Chen, C.
    Shi, Z.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    Activity-based routing algorithm in opportunistic mobile social networks2021In: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, Vol. 17, no 9Article in journal (Refereed)
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  • 41.
    Zhu, Yurong
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Rybarczyk, Yves
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Wang, X.
    A Review on Data-driven Methods for Studying Hygrothermal Transfer in Building Exterior Walls2023In: ICBDT '23: Proceedings of the 2023 6th International Conference on Big Data Technologies, ACM Press, 2023, p. 33-41Conference paper (Refereed)
    Abstract [en]

    This review aims to comprehensively assess and synthesize the existing literature on the use of data-driven methods for studying hygrothermal transfer in building exterior walls. The review is conducted by an exhaustive search strategy to identify relevant articles from Web of Science and Scopus databases. There are 20 eligible studies included in this review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. The most used data-driven methods are traditional neural networks, such as Multi-Layer Perceptrons and 2D Convolutional Neural Networks. Results suggested that neural network models hold potential for accurately predicting hygrothermal attributes of building exteriors. However, a conspicuous gap in the literature is the absence of studies drawing direct comparisons between data-driven methodologies and conventional simulation techniques. © 2023 ACM.

  • 42.
    Zhu, Yurong
    et al.
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Song, William Wei
    Dalarna University, School of Information and Engineering, Informatics. Jiangxi University of Finance and Economics, China.
    Wang, X.
    Rybarczyk, Yves
    Dalarna University, School of Information and Engineering, Microdata Analysis.
    Nyberg, Roger G.
    Dalarna University, School of Information and Engineering, Informatics.
    Fei, B.
    A Novel Approach to Discovering Hygrothermal Transfer Patterns in Wooden Building Exterior Walls2023In: Buildings, E-ISSN 2075-5309, Vol. 13, no 9, article id 2151Article in journal (Refereed)
    Abstract [en]

    To maintain the life of building materials, it is critical to understand the hygrothermal transfer mechanisms (HTM) between the walls and the layers inside the walls. Due to the extreme instability of weather data, the actual data models of the HTM—the data being collected for actual buildings using modern sensor technologies—would appear to be a great difference from any theoretical models, in particular, for wood building materials. In this paper, we aim to consider a variety of data analysis tools for hygrothermal transfer features. A novel approach for peak and valley detection is proposed based on the discrete differentiation of the original data. Not to be limited to the measure of peak and valley delays for HTM, we propose a cross-correlation analysis to obtain the general delay between two daily time series, which seems to be representative of the delay in the daily time series. Furthermore, the seasonal pattern of the hygrothermal transfer combined with the correlation analysis reveals a reasonable relationship between the delays and the indoor and outdoor climates. © 2023 by the authors.

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