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  • 351.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Rahman, Hamidur
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Begum, Shahina
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Quality Index Analysis on Camera-based R-peak Identification Considering Movements and Light Illumination2018In: 15th International Conference on Wearable, Micro & Nano technologies for Personalized Health pHealth2018, 2018Conference paper (Refereed)
    Abstract [en]

    This paper presents a quality index (QI) analysis on R-peak extracted by a camera system considering movements and light illumination. Here, the proposed camera system is compared with a reference system named Shimmer PPG sensor. The study considers five test subjects with a 15 minutes measurement protocol, where the protocol consists of several conditions. The conditions are: normal sittings, head movements i.e., up/down/left/right/forward/backword, with light on/off and with moving flash on/off. A percentage of corrected R-peaks are calculated based on time difference in milliseconds (MS) between the R-peaks extracted both from camera-based and sensor-based systems. A comparison results between normal, movements, and lighting condition is presented as individual and group wise. Furthermore, the comparison is extended considering gender and origin of the subjects. According to the results, more than 90% R-peaks are correctly identified by the camera system with ?200 MS time differences, however, it decreases with while there is no light than when it is on. At the same time, the camera system shows more 95% accuracy for European than Asian men.

  • 352.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Westin, Jerker
    Nyholm, Dag
    Dougherty, Mark
    Groth, Torgny
    A fuzzy rule-based decision support system for Duodopa treatment in Parkinson2006Conference paper (Refereed)
    Abstract [en]

    A decision support system (DSS) was implemented based on a fuzzy logic inference system (FIS) to provide assistance in dose alteration of Duodopa infusion in patients with advanced Parkinson's disease, using data from motor state assessments and dosage. Three-tier architecture with an object oriented approach was used. The DSS has a web enabled graphical user interface that presents alerts indicating non optimal dosage and states, new recommendations, namely typical advice with typical dose and statistical measurements. One data set was used for design and tuning of the FIS and another data set was used for evaluating performance compared with actual given dose. Overall goodness-of-fit for the new patients (design data) was 0.65 and for the ongoing patients (evaluation data) 0.98. User evaluation is now ongoing. The system could work as an assistant to clinical staff for Duodopa treatment in advanced Parkinson's disease.

  • 353.
    Ahmed, Ruqiyo
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Axente, Benedetta
    Mälardalen University, School of Business, Society and Engineering.
    Fathulla, Lana
    Mälardalen University, School of Business, Society and Engineering.
    The Relationship Between Business and Society: A study of corporate philanthropy within organizations2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Date: [2018-06-01]

    Level: Bachelor thesis in Business Administration, 15 cr

    Institution: School of Business, Society and Engineering, Mälardalen University

    Authors: Ruqiyo Ahmed, Benedetta Axente, Lana Fathulla

    Title: The Relationship Between Business And Society

    Supervisor: Konstantin Lampou

    Co-assessor: Pär Blomkvist

    Keywords: CSR, Corporate Philanthropy, Core Competencies, Strategic Philanthropy

    Research Question:  How is corporate philanthropy implemented in an organization?

    Purpose: The purpose of this study is to get a deeper understanding of how organizations implement philanthropy in their business. This study further aims to answer the research question by explaining the essence of strategic philanthropy, how organizations can benefit from it and some misconceptions against philanthropy.

    Method:  This study is done through a qualitative research method. Primary data was collected by semi-structured interviews with three companies. Secondary sources was collected to complement the data collection.

    Conclusion: The findings of this paper suggests that with a strategic philanthropic approach an organization can benefit with an enhanced image and increased customer loyalty. Furthermore, it is proposed that engaging in philanthropic activities an organization will be able to attract and retain their employees. By implementing a strategic philanthropy, an organization can better choose which philanthropic issues to tackle.

  • 354.
    Ahmed, Sayidali
    Mälardalen University, School of Business, Society and Engineering.
    Kompetensutveckling i projektledning: En kompetensutvecklingshandbok för projektingenjörer2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis presents a study of competence and knowledge needs of project engineers to be able to manage projects successfully. The aim of the thesis is to identify how to feedback competences and experiences into the project management process. The guidebook provides guidance to what a project engineer needs to focus on to become more skilled and to become a more effective project manager.

    A literature study was performed to get a better understanding of the project manager's role. A detailed study was performed on the duties of project engineers and project managers. The literature study was based on books and reports as well as an information research by the Internet. An interview with five project managers and five project engineers was conducted to compare theory with practice. Based on the respondents' answers and the results from the literature study a handbook outlining what the project engineer can do to improve their project management skills.

    The thesis concludes that competence development depends on individual motivation. Every individual have their own goals and they are stimulated by different motivational factors. Some aims high to become CEO for a company, while other are satisfied with their positions and it doesn’t mean that all project engineer / project manager strives for continuous development.

    The main question of the thesis was: "What skills are needed for project engineers to develop their skills in project management?”. The results of the thesis show that without learning from their mistakes and problems that were made in previous project and by making their own mistakes the project engineer will not develop or become a more efficient project manager. By learning from experiences from previous projects the project engineer can save significant time when facing similar problems in new projects. Recording and using this knowledge may contribute to more effective solutions and thus reducing time lost unnecessarily.

  • 355.
    Ahmed, Shakeel
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Imtiaz, Muhammad
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Assessing the environmental uncontrollable elements of Swedish market that can influence and haveimpact on the presence of Lithuanian breakfast cereal producer (Palaseja) in Sweden.: A study of Swedish breakfast cereal market2009Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Problem:

    Palaseja is considering Sweden as a prospect market to enter and operate so, a study of Swedish

    business environment and its uncontrollable elements is required for Palaseja to serve this purpose

    effectively.

    Method:

    Thesis has followed a combination of exploratory & descriptive research and a qualitative approach

    has been applied. Both primary and secondary data have been gathered, primary data was gathered

    through interviews from retail stores' officials and Palaseja's sales manager.

    Conclusion:

    In this study, different environmental uncontrollable elements of Swedish market have been explored

    to find out how they can influence a new entrant Palaseja in Sweden. There are a few legal

    requirements for Palaseja to enter in food market of Sweden. Economic forces are facing a little slow

    down effect due to recent global economic slump but are quite encouraging for any new company

    entering Sweden in the long run. Breakfast cereal products that Palaseja produces have found to be a

    common part of cultural breakfast habits and huge consumption of breakfast cereal per capita also

    seems to be encouraging for new comers in this industry. Competitive forces have been found to be

    extremely challenging and quite discouraging in some way. The country of origin effect seems to be

    not so strong in Sweden although brand recognition of Palaseja is likely to cause some trouble to

    Palaseja's success.

  • 356.
    Ahmed, Shehzad
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Moosavi, Zahra
    Mälardalen University, School of Business, Society and Engineering.
    Factors Influencing the Cell Phone Brand Loyalty of Swedish Generation Y.2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 357.
    Ahmed, Zeinab
    Mälardalen University, School of Innovation, Design and Engineering.
    Material och Lagerstyrningssystem2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Previously, Husmuttern had difficulty controlling inventory levels and purchase orders. This had a negative impact on production. The company had no effective system to plan and control inventory levels; material and inventory management was performed by an external supplier. The transport of raw materials was planned every other day and failed to take into account the vehicle’s load capacity, it has affected transport costs and the environment.

    The purpose of the thesis work is to identify problems and provide recommendations, supported by theories of how an efficient material planning system can be implemented, to increase profitability, reduce transport costs, environmental impacts, as well as achieve balance between material flow and demand.

    The results showed that using an effective material planning system, both stock levels and purchase orders are controlled. The student tested using the order point method to control stock levels and purchase orders.

  • 358.
    Ahrlow, Catarina
    et al.
    Mälardalen University, School of Health, Care and Social Welfare, Health and Welfare.
    Leijthoff, Sofia
    Mälardalen University, School of Health, Care and Social Welfare, Health and Welfare.
    "JAG VILLE KUNNA SÄTTA ETT EX FRAMFÖR PROSTITUERAD": Sex kvinnors livsberättelser om sina prostitutionserfarenheter.2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med studien var att beskriva och analysera kvinnors självupplevda erfarenheter av prostitution. Studien önskade besvara frågeställningen: vilka förväntningar, händelser, upplevelser och känslor som format dessa kvinnors resa i steget in, genom och ur prostitution? Studien som var av en kvalitativ ansats har baserats på sex ostrukturerade livsberättelser av kvinnor med erfarenhet av prostitution. Fokus vid intervjuerna har varit kvinnornas egna beskrivningar, upplevelser och känslor av resan in, under och ur prostitution. Studien har haft ett socialpsykologiskt perspektiv som utgångspunkt och dess teoretiska ramverk har bestått av Scheffs begrepp om skam, Goffmans teori om stigma samt Fuchs Ebaugh’s teori “the process of role exit”. Studiens resultat visade på att flera samverkande händelser och upplevelser i kvinnornas liv påverkade deras känslor och förväntningar på sig själva, vilket var framträdande inslag i kvinnornas livsberättelser om deras process, in- genom och ut ur prostitution. Kvinnornas upplevelser och känslor kring prostitutionen framkom vara komplexa. För att kunna bemöta och stödja kvinnor med prostitutionserfarenhet krävs av socialarbetare en förmåga att lyssna utan att döma och kunskap om prostitutionsprocessen. Detta för att inte ytterligare skambelägga och stigmatisera kvinnor med prostitutionserfarenhet.

  • 359.
    Ahrén, Christina
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Nyblad, Ida
    Mälardalen University, School of Innovation, Design and Engineering.
    Investigating DRAM bank partitioning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We have investigated the page coloring technique bank partitioning and if it can be applied on commercial hardware platforms to reduce execution time jitter for specific tasks. We have also investigated how to alter execution times using bank partitioning. Unpredictable latency created by execution time jitter is a problem in real-time computing on commercial hardware platforms. We have run experiments that try to prove that the bank partitioning method we use alters the execution time and that thrashing occurs in the main memory if we run multiple instances of a workload. We receive significant changes in execution times when using bank partitioning and we can determine that thrashing occurs. However, due to the lack of the ability to measure the hardware performance counter for row buffer misses, we cannot determine if thrashing occurs in the main memory level. Since we cannot determine when, or if thrashing occurs in the main memory we find that we cannot reduce execution time jitter on the two systems that we have tested using bank partitioning on. We also find that execution times of specific tasks can be altered by reducing the number of bank bins associated with the specific task. The execution time of the task is increased if we reduce the number of bins associated with it.

  • 360.
    Ahvenlampi Svensson, Amanda
    Mälardalen University, School of Innovation, Design and Engineering, Innovation and Product Realisation.
    Exploring challenges in a verification process - when adapting production processes to new environmental requirements2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The requirements on the products and production processes within the manufacturing industry are continuously increasing according to environmental standards. The new requirements are coming from a growing awareness of what our planet can provide for example by the global challenge of climate change. The industry needs to reduce energy consumption and waste to meet the upcoming requirements.

    One of the processes with high environmental impact in a discrete manufacturing industry is the paint shop. Surface treatment is also of great importance to maintain a high quality product. In scientific literature, technological risk is one of the barriers in implementing environmental conscious manufacturing. Therefore the area of sustainable operations management needs building bridges with other functions and disciplines such as economics, strategies and behavioral sciences in order to manage the transitions. The supply of competence around paint shops today is usually provided by suppliers and other sources within the industry and to make the collaboration to work is essential. In this process of collaboration with external sources, substantial measurements are required to maintain the desirable quality. In order to ensure the competence of testing the quality eventuate when switching technology at a pre-treatment line, this report sets out to explore what the challenges to be taken into consideration are when to assure the product- and- process quality. To respond to this question, a multiple case study is conducted during spring 2016 where the phenomenon to study is the change process and the unit of analysis is the challenges that can be faced during the verification process. The case studied is automotive companies located in Sweden which are producing components for heavy duty vehicles. Data collection is performed by studying documents, participatory observations and semi-structured interviews. The results will give insights to academia on what challenges that are occurring during the verification process of implementing new and cleaner technologies. The conclusions are drawn upon the literature and the empirical results. The managerial implications are to increase the awareness of any potential barriers in the verification process in order to be prepared for managing the technological change process.

  • 361.
    Ahy, Nathaniel
    et al.
    Mälardalen University, School of Education, Culture and Communication.
    Sierra, Mikael
    Mälardalen University, School of Education, Culture and Communication.
    Implied Volatility Surface Approximation under a Two-Factor Stochastic Volatility Model2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Due to recent research disproving old claims in financial mathematics such as constant volatility in option prices, new approaches have been incurred to analyze the implied volatility, namely stochastic volatility models. The use of stochastic volatility in option pricing is a relatively new and unexplored field of research with a lot of unknowns, where new answers are of great interest to anyone practicing valuation of derivative instruments such as options. With both single and two-factor stochastic volatility models containing various correlation structures with respect to the asset price and differing mean-reversions of variance the question arises as to how these values change their more observable counterpart: the implied volatility. Using the semi-analytical formula derived by Chiarella and Ziveyi, we compute European call option prices. Then, through the Black–Scholes formula, we solve for the implied volatility by applying the bisection method. The implied volatilities obtained are then approximated using various models of regression where the models’ coefficients are determined through the Moore–Penrose pseudo-inverse to produce implied volatility surfaces for each selected pair of correlations and mean-reversion rates. Through these methods we discover that for different mean-reversions and correlations the overall implied volatility varies significantly and the relationship between the strike price, time to maturity, implied volatility are transformed.

  • 362.
    Aisa, J.
    et al.
    Universidad de Zaragoza, Zaragoza, Spain .
    Fotouhi, Hossein
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Villarroel, J. L.
    Universidad de Zaragoza, Zaragoza, Spain .
    Almeida, L.
    University of Porto, Porto, Portugal.
    Soft real-time traffic communication in loaded Wireless Mesh Networks2016In: IEEE International Workshop on Factory Communication Systems - Proceedings, WFCS, 2016, article id Article number 7496503Conference paper (Refereed)
    Abstract [en]

    Industrial applications have been shifting towards wireless multi-hop networks in recent years due to their lower cost of deployment and reconfiguration compared with their wired counterparts. These wireless networks usually must support real-time communication to meet the application requirements. For this reason, Wireless Mesh Networks (WMNs) are potential candidates for industrial applications as they support a fixed infrastructure of static nodes for relaying packets. To meet the application demands, we modify the wireless chain network protocol (WICKPro) to support soft real-time traffic in WMNs with chain topologies over IEEE 802.11. We employ tele-operation of mobile robots as our case study, and perform extensive simulation and laboratory experiments. We show that the data delivery ratio is increased up to 42% in a scenario with 7 nodes, when the maximum end-to-end delay tolerated by the application is doubled. This is particularly suited to soft real-time applications that can trade longer delays by higher reliability. Moreover, when compared with a distributed priority-based token-passing protocol (RT-WMP), the lower overhead of WICKPro allows, in an error-free scenario, obtaining a throughput improvement of 33.42% on average.

  • 363.
    Aisa, Jesus
    et al.
    Universidad de Zaragoza, Zaragoza, Spain.
    Fotouhi, Hossein
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Almeida, Luis
    University of Porto, Portugal.
    Villarroel, José Luis
    Universidad de Zaragoza, Zaragoza, Spain.
    DoTHa - A Double-threshold Hand-off Algorithm for Managing Mobility in Wireless Mesh Networks2016In: 21st IEEE Conference on Emerging Technologies and Factory Automation ETFA'16, 2016, article id 7733511Conference paper (Refereed)
    Abstract [en]

    Wireless communication will play an increasingly important role in future factory automation and process control, where the presence of mobile autonomous devices is expected to grow. However, wireless links are prone to errors due to shadowing and multi-path fading, which is even more severe in dynamic environments. These problems can be attenuated by using a mesh backbone to which mobile node connect to, using a hand-off algorithm. This solution is particularly important under real-time requirements typically found in factory automation. In this paper, we devise the Double-Threshold Hand-off (DoTHa) algorithm, a novel hand-off mechanism that triggers a hand-off in various environmental conditions. As a case study, we carry out the tele-operation of a mobile robot through a wireless mesh network in an indoor setting, using a wireless chain network protocol (WICKPro-SRT) that supports soft real-time traffic. We empirically compared DoTHa with two existing hand-off algorithms based on single and double hysteresis margin. The results revealed that DoTHa achieves Data Delivery Ratio (DDR) close to 100% whereas the single hysteresis-based hand-off suffers from frequent disconnections, dropping DDR to 88%. The double hysteresis-based hand-off shows higher ping-pong effect than DoTHa, doubling the number of hand-offs in some scenarios.

  • 364.
    Ajamlou, Anita
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Ekberg, Andreas
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Gülünay, Michel
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Revisionspliktens avskaffande: Påverkan på revisionsbyråer och deras marknadsföring2011Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna uppsats är att ta reda på hur vissa svenska revisionsbyråer påverkats av avskaffandet av revisionsplikten. Studien medför även hur svenska revisionsbyråer ska agera för att behålla sina nuvarande kunder.

  • 365.
    Ajmaya, Davi
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Eklund, Dennis
    Mälardalen University, School of Innovation, Design and Engineering.
    Machine learning based pedestrian event monitoring using IMU and GPS2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Understanding the behavior of pedestrians in road transportation is critical to maintain a safe en- vironment. Accidents on road transportation are one of the most common causes of death today. As autonomous vehicles start to become a standard in our society, safety on road transportation becomes increasingly important. Road transportation is a complex system with a lot of dierent factors. Identifying risky behaviors and preventing accidents from occurring requires better under- standing of the behaviors of the dierent persons involved. In this thesis the activities and behavior of a pedestrian is analyzed. Using sensor data from phones, eight dierent events of a pedestrian are classied using machine learning algorithms. Features extracted from phone sensors that can be used to model dierent pedestrian activities are identied. Current state of the art literature is researched to nd relevant machine learning algorithms for a classication model. Two models are implemented using two dierent machine learning algorithms: Articial Neural Network and Hid- den Markov Model. Two dierent experiments are conducted where phone sensor data is collected and classied using the models, achieving a classication accuracy of up to 93%.

  • 366.
    Ajmaya, Vana
    et al.
    Mälardalen University, School of Education, Culture and Communication. Kvinna.
    Shabo, Marjana
    Mälardalen University, School of Education, Culture and Communication.
    Elever med matematikängslan: En kvalitativ studie om matematiklärares syn på matematikängslan samt hur de arbetar för att förebygga detta hos elever2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna studie undersöktes det hur matematiklärare i mellanstadiet uppfattar fenomenet matematikängslan samt vilka faktorer de anser påverkar elevers inställning kring matematik. Vidare syftade studien till att inhämta kunskaper om hur dessa lärare arbetar för att förebygga att matematikängslan uppstår bland elever. Precis som när elever kan känna sig ängsliga över andra saker, upplever elever med matematikängslan att de är spända och att de inte är kapabla till att genomföra olika matematiska moment (Dowker, 2016). Studien är baserad på den socialkognitiva teorin som är grundad av Albert Bandura (2012). Han menar att elevernas affektiva upplevelser och lärande uppstår när människor observerar och imiterar andra, samtidigt som de är uppmärksamma, använder sitt minne och har motivation (Bandura, 2012). För att svara på våra forskningsfrågor har vi haft semistrukturerade intervjuer med möjlighet för följdfrågor. Informanterna beskrev begreppet matematikängslan som en känsla där eleverna känner sig oroliga och frånvarande från lektionerna. Resultatet visar att de faktorer som påverkar elevers matematikängslan är individanpassning, inställning, erfarenhet, kön och ålder. Vidare beskrev informanterna att matematikängslan kan förebyggas genom att läraren bland annat skapar ett tryggt och lärorikt lärandeklimat samt har en positiv inställning till matematikämnet.

  • 367.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security2017In: Social Robotics: 9th International Conference, ICSR 2017, Tsukuba, Japan, November 22-24, 2017, Proceedings / [ed] Kheddar, A.; Yoshida, E.; Ge, S.S.; Suzuki, K.; Cabibihan, J-J:, Eyssel, F:, He, H., Springer International Publishing , 2017, p. 628-637Conference paper (Refereed)
    Abstract [en]

    The aim of the study presented in this paper is to develop a quantitative evaluation tool of the sense of safety and security for robots in eldercare. By investigating the literature on measurement of safety and security in human-robot interaction, we propose new evaluation tools. These tools are semantic differential scale questionnaires. In experimental validation, we used the Pepper robot, programmed in the way to exhibit social behaviors, and constructed four experimental conditions varying the degree of the robot’s non-verbal behaviors from no gestures at all to full head and hand movements. The experimental results suggest that both questionnaires (for the sense of safety and the sense of security) have good internal consistency.

  • 368.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Enhancing Social Human-Robot Interaction with Deep Reinforcement Learning.2018In: Proc. FAIM/ISCA Workshop on Artificial Intelligence for Multimodal Human Robot Interaction, 2018, MHRI , 2018, p. 48-50Conference paper (Refereed)
    Abstract [en]

    This research aims to develop an autonomous social robot for elderly individuals. The robot will learn from the interaction and change its behaviors in order to enhance the interaction and improve the user experience. For this purpose, we aim to use Deep Reinforcement Learning. The robot will observe the user’s verbal and nonverbal social cues by using its camera and microphone, the reward will be positive valence and engagement of the user.

  • 369.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Relevance of Social Cues in Assistive Training with a Social Robot2018In: 10th International Conference on Social Robotics, ICSR 2018, Proceedings / [ed] Ge, S.S., Cabibihan, J.-J., Salichs, M.A., Broadbent, E., He, H., Wagner, A., Castro-González, Á., Springer , 2018, p. 462-471Conference paper (Refereed)
    Abstract [en]

    This paper examines whether social cues, such as facial expressions, can be used to adapt and tailor a robot-assisted training in order to maximize performance and comfort. Specifically, this paper serves as a basis in determining whether key facial signals, including emotions and facial actions, are common among participants during a physical and cognitive training scenario. In the experiment, participants performed basic arm exercises with a social robot as a guide. We extracted facial features from video recordings of participants and applied a recursive feature elimination algorithm to select a subset of discriminating facial features. These features are correlated with the performance of the user and the level of difficulty of the exercises. The long-term aim of this work, building upon the work presented here, is to develop an algorithm that can eventually be used in robot-assisted training to allow a robot to tailor a training program based on the physical capabilities as well as the social cues of the users.

  • 370.
    Akalin, Neziha
    et al.
    Örebro University, Sweden.
    Kristoffersson, Annica
    Mälardalen University, School of Innovation, Design and Engineering.
    Loutfi, Amy
    Örebro University, Sweden.
    Evaluating the Sense of Safety and Security in Human–Robot Interaction with Older People2019In: Social Robots: Technological, Societal and Ethical Aspects of Human-Robot Interaction / [ed] Oliver Korn, Springer, Cham , 2019, p. 237-264Chapter in book (Refereed)
    Abstract [en]

    For many applications where interaction between robots and older people takes place, safety and security are key dimensions to consider. ‘Safety’ refers to a perceived threat of physical harm, whereas ‘security’ is a broad term which refers to many aspects related to health, well-being, and aging. This chapter presents a quantitative evaluation tool of the sense of safety and security for robots in elder care. By investigating the literature on measurement of safety and security in human–robot interaction, we propose new evaluation tools specially tailored to assess interaction between robots and older people.

  • 371.
    Akan, Batu
    Mälardalen University, School of Innovation, Design and Engineering.
    Human Robot Interaction Solutions for Intuitive Industrial Robot Programming2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past few decades the use of industrial robots has increased the efficiency as well as competitiveness of many companies. Despite this fact, in many cases, robot automation investments are considered to be technically challenging. In addition, for most small and medium sized enterprises (SME) this process is associated with high costs. Due to their continuously changing product lines, reprogramming costs are likely to exceed installation costs by a large margin. Furthermore, traditional programming methods for industrial robots are too complex for an inexperienced robot programmer, thus assistance from a robot programming expert is often needed.  We hypothesize that in order to make industrial robots more common within the SME sector, the robots should be reprogrammable by technicians or manufacturing engineers rather than robot programming experts. In this thesis we propose a high-level natural language framework for interacting with industrial robots through an instructional programming environment for the user.  The ultimate goal of this thesis is to bring robot programming to a stage where it is as easy as working together with a colleague.In this thesis we mainly address two issues. The first issue is to make interaction with a robot easier and more natural through a multimodal framework. The proposed language architecture makes it possible to manipulate, pick or place objects in a scene through high level commands. Interaction with simple voice commands and gestures enables the manufacturing engineer to focus on the task itself, rather than programming issues of the robot. This approach shifts the focus of industrial robot programming from the coordinate based programming paradigm, which currently dominates the field, to an object based programming scheme.The second issue addressed is a general framework for implementing multimodal interfaces. There have been numerous efforts to implement multimodal interfaces for computers and robots, but there is no general standard framework for developing them. The general framework proposed in this thesis is designed to perform natural language understanding, multimodal integration and semantic analysis with an incremental pipeline and includes a novel multimodal grammar language, which is used for multimodal presentation and semantic meaning generation.

  • 372.
    Akan, Batu
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Planning and Sequencing Through Multimodal Interaction for Robot Programming2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past few decades the use of industrial robots has increased the efficiency as well as the competitiveness of several sectors. Despite this fact, in many cases robot automation investments are considered to be technically challenging. In addition, for most small and medium-sized enterprises (SMEs) this process is associated with high costs. Due to their continuously changing product lines, reprogramming costs are likely to exceed installation costs by a large margin. Furthermore, traditional programming methods of industrial robots are too complex for most technicians or manufacturing engineers, and thus assistance from a robot programming expert is often needed. The hypothesis is that in order to make the use of industrial robots more common within the SME sector, the robots should be reprogrammable by technicians or manufacturing engineers rather than robot programming experts. In this thesis, a novel system for task-level programming is proposed. The user interacts with an industrial robot by giving instructions in a structured natural language and by selecting objects through an augmented reality interface. The proposed system consists of two parts: (i) a multimodal framework that provides a natural language interface for the user to interact in which the framework performs modality fusion and semantic analysis, (ii) a symbolic planner, POPStar, to create a time-efficient plan based on the user's instructions. The ultimate goal of this work in this thesis is to bring robot programming to a stage where it is as easy as working together with a colleague.This thesis mainly addresses two issues. The first issue is a general framework for designing and developing multimodal interfaces. The general framework proposed in this thesis is designed to perform natural language understanding, multimodal integration and semantic analysis with an incremental pipeline. The framework also includes a novel multimodal grammar language, which is used for multimodal presentation and semantic meaning generation. Such a framework helps us to make interaction with a robot easier and more natural. The proposed language architecture makes it possible to manipulate, pick or place objects in a scene through high-level commands. Interaction with simple voice commands and gestures enables the manufacturing engineer to focus on the task itself, rather than the programming issues of the robot. The second issue addressed is due to inherent characteristics of communication with the use of natural language; instructions given by a user are often vague and may require other actions to be taken before the conditions for applying the user's instructions are met. In order to solve this problem a symbolic planner, POPStar, based on a partial order planner (POP) is proposed. The system takes landmarks extracted from user instructions as input, and creates a sequence of actions to operate the robotic cell with minimal makespan. The proposed planner takes advantage of the partial order capabilities of POP to execute actions in parallel and employs a best-first search algorithm to seek the series of actions that lead to a minimal makespan. The proposed planner can also handle robots with multiple grippers, parallel machines as well as scheduling for multiple product types.

  • 373.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ameri E., Afsh
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Towards Creation of Robot Programs Through User InteractionManuscript (preprint) (Other academic)
    Abstract [en]

    This paper proposes a novel system for task-level programming of industrial robots. The user interacts with an industrial robot by giving instructions in a structured natural language and by selecting objects through an augmented reality interface. The proposed system consists of two parts. First, a multimodal framework that provides a natural language interface to the user. This framework performs modality fusion, semantic analysis and helps the user to interact with the system easier and more naturally. The proposed language architecture makes it possible to manipulate, pick or place objects in a scene through high-level commands. The second component is the POPStar planner, which is based on partial order planner (POP), that takes landmarks extracted from user instructions as input, and creates a sequence of actions to operate the robotic cell with minimal makespan. The proposed planner takes advantage of partial order capabilities of POP to plan execution of actions in parallel and employs a best-first search algorithm to seek a series of actions that lead to a minimal makespan. The proposed planner can as well handle robots with multiple grippers, and  parallel machines. Using different topologies for the landmark graphs, we show that it is possible to create schedules for changing object types, which are processed in different stages in the robot cell. Results show that the proposed system can create and adapt schedules for robot cells with changing product types in low volume production based on the user's instructions.

  • 374.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ameri E., Afshin
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Curuklu, Baran
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Scheduling for Multiple Type Objects Using POPStar Planner2014In: Proceedings of the 19th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA'14), Barcelona, Spain, September, 2014, 2014, p. Article number 7005148-Conference paper (Refereed)
    Abstract [en]

    In this paper, scheduling of robot cells that produce multiple object types in low volumes are considered. The challenge is to maximize the number of objects produced in a given time window as well as to adopt the  schedule for changing object types. Proposed algorithm, POPStar, is based on a partial order planner which is guided by best-first search algorithm and landmarks. The best-first search, uses heuristics to help the planner to create complete plans while minimizing the makespan. The algorithm takes landmarks, which are extracted from user's instructions given in structured English as input. Using different topologies for the landmark graphs, we show that it is possible to create schedules for changing object types, which will be processed in different stages in the robot cell. Results show that the POPStar algorithm can create and adapt schedules for robot cells with changing product types in low volume production.

  • 375.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Ameri E., Afshin
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering.
    Augmented Reality-based Industrial Robot Control2011In: Proceedings of SIGRAD 2011 / [ed] Larsson, Thomas ; Kjelldahl, Lars ; Jää-Aro, Kai-Mikael, Linköping University Electronic Press, 2011, p. 113-114Conference paper (Refereed)
    Abstract [en]

    Most of the interfaces which are designed to control or program industrial robots are complex and require special training for the user. This complexity alongside the changing environment of small medium enterprises (SMEs) has lead to absence of robots from SMEs. The costs of (re)programming the robots and (re)training the robot users exceed initial costs of installation. In order to solve this shortcoming, we propose a new interface which uses augmented reality (AR) and multimodal human-robot interaction. We show that such an approach allows easier manipulation of robots at industrial environments.

  • 376.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ameri E., Afshin
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Asplund, Lars
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Intuitive Industrial Robot Programming Through Incremental Multimodal Language and Augmented Reality2011In: 2011 IEEE International Conferance on Robotics and Automation (ICRA 2011), IEEE , 2011, p. 3934-3939Conference paper (Refereed)
    Abstract [en]

    Developing easy to use, intuitive interfaces is crucial to introduce robotic automation to many small medium sized enterprises (SMEs). Due to their continuously changing product lines, reprogramming costs exceed installation costs by a large margin. In addition, traditional programming methods for industrial robots is too complex for an inexperienced robot programmer, thus external assistance is often needed. In this paper a new incremental multimodal language, which uses augmented reality (AR) environment, is presented. The proposed language architecture makes it possible to manipulate, pick or place the objects in the scene. This approach shifts the focus of industrial robot programming from coordinate based programming paradigm, to object based programming scheme. This makes it possible for non-experts to program the robot in an intuitive way, without going through rigorous training in robot programming.

  • 377.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering.
    Asplund, Lars
    Mälardalen University, School of Innovation, Design and Engineering.
    Interacting with industrial robots through a multi-modal language and sensory systems2008In: 39th International Sysmposium on Robotics, Seoul, Korea, 2008, p. 66-69Conference paper (Refereed)
    Abstract [en]

    Over the past few decades the use of industrial robots has increased a company's efficiency as well as strengthening their competitiveness in the market.

    Despite this fact, in many cases, robot automation investments are considered to be technically challenging as well as costly by small and medium sized enterprises (SME). We hypothesize that in order to make industrial robots more common within the SME sector, the robots should be reprogrammable by task experts rather than robot programming experts. Within this project we propose to develop a high level language for intelligent human robot interaction that relies on multi-sensor inputs providing an abstract instructional programming environment for the user. Eventually to bring robot programming to stage where it is as easy as working together with a colleague

  • 378.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Asplund, Lars
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Scheduling POP-Star for Automatic Creation of Robot Cell Programs2013Conference paper (Refereed)
    Abstract [en]

    Typical pick and place, and machine tending applications often require an industrial robot to be embedded in a cell and to communicate with other devices in the cell. Programming the program logic is a tedious job, requiring expert programming knowledge, and it can take more time than programming the specific robot movements itself. We propose a new system, which takes in the description of the whole manufacturing process in natural language as input, fills in the implicit actions, and plans the sequence of actions to accomplish the task described in minimal makespan using a modified partial planning algorithm. Finally we demonstrate that the proposed system can come up with a sensible plan for the given instructions.

  • 379.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering.
    Spampinato, Giacomo
    Mälardalen University, School of Innovation, Design and Engineering.
    Asplund, Lars
    Mälardalen University, School of Innovation, Design and Engineering.
    Object selection using a spatial language for flexible assembly2009Conference paper (Refereed)
  • 380.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering.
    Spampinato, Giacomo
    Mälardalen University, School of Innovation, Design and Engineering.
    Asplund, Lars
    Mälardalen University, School of Innovation, Design and Engineering.
    Object Selection using a Spatial Language for Flexible Assembly2009In: 14th IEEE International Conference on Emerging Technologies and Factory Automation, 2009. (ETFA 2009), Mallorca, Spain, 2009Conference paper (Refereed)
    Abstract [en]

    In this paper we present a new simplified natural language that makes use of spatial relations between the objects in scene to navigate an industrial robot for simple pick and place applications. Developing easy to use, intuitive interfaces is crucial to introduce robotic automation to many small medium sized enterprises (SMEs). Due to their continuously changing product lines, reprogramming costs are far higher than installation costs. In order to hide the complexities of robot programming we propose a natural language where the use can control and jog the robot based on reference objects in the scene. We used Gaussian kernels to represent spatial regions, such as left or above. Finally we present some dialogues between the user and robot to demonstrate the usefulness of the proposed system.

  • 381.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering.
    Spampinato, Giacomo
    Mälardalen University, School of Innovation, Design and Engineering.
    Asplund, Lars
    Mälardalen University, School of Innovation, Design and Engineering.
    Towards Robust Human Robot Collaboration in Industrial Environments2010In: 5th ACM/IEEE International Conference on Human-Robot Interaction, HRI 2010, 2010, p. 71-72Conference paper (Refereed)
    Abstract [en]

    In this paper a system, which is driven through natural language, that allows operators to select and manipulate objects in the environment using an industrial robot is proposed. In order to hide the complexities of robot programming we propose a natural language where the user can control and jog the robot based on reference objects in the scene. We used semantic networks to relate different types of objects in the scene

  • 382.
    Akbari, Keramatollah
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Impact of Radon Ventilation on Indoor Air Quality and Building Energy saving2009Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Industrial living is caused much people do live and work in closed and confined places; offices and residential buildings. This is why in this new world more fresh air which is generally provided by forced ventilation plays a vital role in living of human being. Furthermore because of many different indoor pollutants, like radon and artificial pollutants, the amount of fresh air and in turn the energy consumption has increased. This energy consumption related to ventilation has reached up to about 30 percent of energy used of building section. So making interaction between indoor air quality (IAQ) and optimization of energy saving is a necessary work.  Radon as a natural pollutant is occurred in environment and in many countries threatens people health whereas is called the second causes of cancer. For reducing radon concentration in residential building at the acceptable level forced ventilation is used usually. Ventilation can improve IAQ but in the other side would increase the energy consumption in building sector and just now the contribution of ventilation exceeds up 50 percent of building sector's share. The aim of this thesis is to study the impact of ventilation on indoor radon by using Computational Fluid Dynamics (CFD) to achieve indoor air quality and energy efficiency. Application of CFD as a new technology, because of its cost and time savings, and on the other side, of its flexibility and precision is  increasingly grown and can be used as a very important and valuable tool for the prediction and measurement of radon distribution in a ventilated building . Currently, measurement techniques and proposed standards and regulations of indoor pollutants and ventilation, particularly related to indoor radon cannot be able to provide a secure, safe and energy efficient indoor climate. This is why the indoor airflow distribution is very complex and with changing building geometry and operation condition, the treatment of air flow pattern, substantially would be changed, whereas the rules are usually independent of the buildings features. Furthermore, the indoor standards and regulations are based on average amount of pollutants in a room, whereas the pollutant distributions aren't identical and are varied throughout the room. Then the current techniques aren't so exactly valuable and acceptable.

    From different methods which is privilege to control pollutants, ventilation method is applicable in existing buildings. Designing effective ventilation can reduce radon concentration to very level low with regarding energy conservation remarks.

     

    This thesis presents results from simulation studies on ventilation and radon mitigation in residential buildings, in view points of indoor air quality and energy savings. The CFD technique is applied to predict, visualize and calculate of mixture radon-air flow. The distribution of indoor radon concentration, air velocity and room temperature also have considered together for achieving indoor air quality and energy saving. The results are also compared with the experimental data and related previous works.

     

    It was found that with increasing ventilation rate, the radon concentration is decreased, but the location of ventilation system is also important. From the simulation results, it is observed that within the ventilated room, there are some zones, which are good for living and somewhere is more polluted. The traditional radon detectors basically show the average value of radon content in 1m­3 of air. That is why detector measuring is not exact and safe.

     

    Simulation results proved that floor heat can be supported ventilation effect and speed up the mixture movement. Floor heating reinforces the buoyancy effect, which is useful to reduce radon content in the floor (seating area) and then lower ventilation rate can be applied.

  • 383.
    Akbari, Keramatollah
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Influence of residential ventilation on Radon mitigation with energy saving emphasis2009In:  PROCEEDINGS FROM SCIENTIFIC CONFERENCE ON GREEN ENERGY AND IT, 2009Conference paper (Refereed)
    Abstract [en]

    There are many indoor pollutants in the residential buildings. High insulation and tightness in buildings in order to increase energy efficiency and to lower energy costs is led to the indoor air quality problems. To provide sufficient fresh air and to promote indoor air quality at acceptable level, it is needed to increase ventilation rate to overcome such pollutants.  

    The aim of this paper is to study about energy efficient mechanical ventilation to overcome poor indoor air quality and energy consumption associated with radon ventilation.

     

    Ventilation is a good method to dilute radon contaminant and maintain indoor air quality, but in the other hand ventilation is account for about 50 percent of energy use in residential buildings. Designing the required rate and location of ventilation systems and also choosing the best type of ventilation strategies can be provided both indoor air quality (IAQ) and building energy savings (BES).

     Computational fluid dynamics technique as a useful tool can be used to simulate and visualize radon treatment and mechanical ventilation rates for optimizing energy consumption and achieving to indoor air quality.

    Results show that the exhaust fan installed in the middle another one in the left side have different impacts on distribution of radon contents in the room. Also when the rate of ventilation is changed from 7.5 l/s to 35 l/s the radon concentration will be decreased. By choosing the optimum features of ventilation system, energy saving can be obtained.

  • 384.
    Akbari, Keramatollah
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Simulation of Indoor Radon and Energy Recovery Ventilation Systems in Residential Buildings2015Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This study aims to investigate the effects of ventilation rate, indoor air temperature, humidity and using a heat recovery ventilation system on indoor radon concentration and distribution.

    Methods employed include energy dynamic and computational fluid dynamics simulation, experimental measurement and analytical investigations. Experimental investigations primarily utilize a continuous radon meter and a detached house equipped with a recovery heat exchanger unit.

    The results of the dynamic simulation show that the heat recovery unit is cost-effective for the cold Swedish climate and an energy saving of about 30 kWh per  floor area per year is possible, while it can be also used to lower radon level.

    The numerical results showed that ventilation rate and ventilation location have significant impacts on both radon content and distribution, whereas indoor air temperature only has a small effect on radon level and distribution and humidity has no impact on radon level but has a small impact on its distribution.

  • 385.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Mahmoudi, Jafar
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Effects of Heat Recovery Ventilation Systems on Indoor Radon2012In: PROCEEDINGS OF ECOS 2012 - THE 25TH INTERNATIONAL CONFERENCE ON EFFICIENCY, COST, OPTIMIZATION, SIMULATION AND ENVIRONMENTAL IMPACT OF ENERGY SYSTEMS / [ed] ECOS, 2012, , p. 10p. 1-10Conference paper (Refereed)
    Abstract [en]

    A heat recovery ventilation system enables us to control indoor conditions such as ventilation rate,

    temperature, relative humidity and pressure difference. These environmental conditions affect indoor radon

    levels.

    Computational fluid dynamics (CFD) is a powerful tool for predicting and visualizing radon content and indoor

    air quality and is cost effective in comparison with other methods such as full scale laboratory and gas trace

    techniques.

    In this study a mechanically balanced ventilation system and a continuous radon monitor (CRM) were used

    to measure the indoor ventilation rate and radon levels. In a numerical approach the FLUENT CFD package

    was used to simulate radon entry into the building and effects on indoor air conditions.

    The effects of different ventilation rates, indoor temperature and relative humidity on indoor radon

    concentrations were investigated in a one family detached house in Stockholm. Results of numerical studies

    indicated that changes of ventilation rate, indoor temperature and moisture by means of ventilation systems

    have significant effects on indoor radon content. Ventilation rate was inversely proportional to indoor radon

    concentration. Minimum radon levels were estimated in the range of thermal comfort, i.e. at 21 and

    relative humidity between 50-70%.

    The analytical solution was used to validate numeric results at 3 distinct air change rates. Comparisons

    between numerical and analytical results showed good agreement but there was poor agreement between

    simulations and measurement results due to the short measuring period.

  • 386.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Mahmoudi, Jafar
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Numerical Simulation of Radon Transport and Indoor Air Conditions Effects2012In: International journal of scientific and Engineering Research, ISSN 2229-5518, Vol. 3, no 6, p. 1-10Article in journal (Refereed)
    Abstract [en]

    Computational fluid dynamics (CFD) is a powerful tool for predicting and visualizing radon content and indoor air quality and is cost effective in comparison with other methods such as full scale laboratory and gas trace techniques. The intention of this article is to use CFD to simulate indoor radon distribution and ventilation effects. In this study a mechanically balanced ventilation system and a continuous radon monitor (CRM) were used to measure the indoor ventilation rate and radon levels. In a numerical approach the FLUENT CFD package was used to simulate radon entry into the building and effects on indoor air conditions. The effects of different ventilation rates, indoor temperature and relative humidity on indoor radon concentrations were investigated in a one family de-tached house in Stockholm. Results of numerical studies indicated that changes of ventilation rate, indoor temperature and moisture by means of ventila-tion systems have significant effects on indoor radon content. Ventilation rate was inversely proportional to indoor radon concentration. Minimum radon levels were estimated in the range of thermal comfort, i.e. at 21 and relative humidity between 50-70%. The analytical solution was used to validate numeric results at 3 distinct air change rates. Comparisons between numerical and analytical results showed good agreement but there was poor agreement between simulations and measurement results due to the short measuring period.

  • 387.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Mahmoudi, Jafar
    Simulation of Radon Mitigation in Residential Building2008Conference paper (Refereed)
  • 388.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Mahmoudi, Jafar
    Mälardalen University, School of Business, Society and Engineering.
    Ghanbari, M.
    Sharif University of Technology, Tehran, Iran .
    Simulation of ventilation effects on indoor radon2013In: Management of environmental quality, ISSN 1477-7835, E-ISSN 1758-6119, Vol. 24, no 3, p. 394-407Article in journal (Refereed)
    Abstract [en]

    Purpose: The purpose of this paper is to describe the use of computational fluid dynamics (CFD) to simulate indoor radon distribution and ventilation effects. This technique was used to predict and visualize radon content and indoor air quality in a one-family detached house in Stockholm. The effects of intake fans, exhaust fans and doors on radon concentration were investigated. Design/methodology/approach: In this study a mechanically balanced ventilation system and a continuous radon monitor (CRM) were used to measure the indoor ventilation rate and radon levels. In a numerical approach, the FLUENT CFD package was used to simulate radon entry into the building and ventilation effects. Findings: Results of the numerical study indicated that indoor pressure created by ventilation systems and infiltration through doors or windows have significant effects on indoor radon content. The location of vents was found to affect the indoor radon level and distribution. Research limitations/implications: It may be possible to improve any discrepancies found in this article by using a more refined representation of grids and certain boundary conditions, such as pressure and temperature differences between inside and outside and by considering some real situations in residential buildings and external situations. Originality/value: From the viewpoints of indoor air quality (IAQ) and energy savings, ventilation has two opposing functions; on the positive side it enhances IAQ and the establishment of thermal comfort, and on the negative side it increases energy consumption. This paper describes the search for a solution to cope with this contradiction.

  • 389.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Mahmoudi, Jafar
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Ghanbari, Mahdi
    Sharif University of Technology, Tehran, Iran.
    Influence of indoor air conditions on radon concentration in a detached house2013In: Journal of Environmental Radioactivity, ISSN 0265-931X, E-ISSN 1879-1700, ISSN ISSN 0265-931X, EISSN 1879-1700, Vol. 116, p. 166-173Article in journal (Refereed)
    Abstract [en]

    Radon is released from soil and building materials and can accumulate in residential buildings. Breathing radon and radon progeny for extended periods hazardous to health and can lead to lung cancer. Indoor air conditions and ventilation systems strongly influence indoor radon concentrations. This paper focuses on effects of air change rate, indoor temperature and relative humidity on indoor radon concentrations in a one family detached house in Stockholm, Sweden.In this study a heat recovery ventilation system unit was used to control the ventilation rate and a continuous radon monitor (CRM) was used to measure radon levels. FLUENT, a computational fluid dynamics (CFD) software package was used to simulate radon entry into the building and air change rate, indoor temperature and relative humidity effects using a numerical approach.The results from analytical solution, measurements and numerical simulations showed that air change rate, indoor temperature and moisture had significant effects on indoor radon concentration. Increasing air change rate reduces radon level and for a specific air change rate (in this work Ach = 0.5) there was a range of temperature and relative humidity that minimized radon levels. In this case study minimum radon levels were obtained at temperatures between 20 and 22 °C and a relative humidity of 50-60%

  • 390.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Mahmoudi, Jafar
    Mälardalen University, School of Business, Society and Engineering.
    Öman, Robert
    Mälardalen University, School of Business, Society and Engineering.
    Simulation of ventilation effects on indoor radon in a detached house2012In: WSEAS Transactions on Fluid Mechanics, ISSN 1790-5087, Vol. 7, no 4, p. 146-155Article in journal (Refereed)
    Abstract [en]

    CFD is widely used in indoor air quality, air flow pattern, indoor pollutant distribution and thermal comfort as a cost effective and powerful tool and it can be used to predict, estimate and visualize the indoor radon level. The intention of this article is to use computational fluid dynamics (CFD), as a standalone tool to simulate indoor radon distribution and ventilation effects. This technique can be used to predict and visualize radon content and indoor air quality throughout a one family detached house in Stockholm. In this study a mechanical balanced ventilation system and a continuous radon monitor (CRM) were also used to measure the indoor ventilation rate and radon levels. In numerical approach the FLUENT, CFD package was used to simulate radon entry into the building and ventilation effects. Results of numerical study indicated that indoor pressure made by means of ventilation systems and infiltration through door or window has significant effects on indoor radon content. It is observed that the location of vents can affect the indoor radon level, particularly in breathing (seating) zone. The analytic solution is used to validate numeric results at 3 distinct air change rates. The comparison amongst analytical, numerical and measurement results shows close agreement.

  • 391.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Oman, Robert
    Mälardalen University, School of Business, Society and Engineering.
    Impacts of heat recovery ventilators on energy savings and indoor radon level2013In: Management of environmental quality, ISSN 1477-7835, E-ISSN 1758-6119, Vol. 24, no 5, p. 682-694Article in journal (Refereed)
    Abstract [en]

    Purpose: This paper aims to investigate the impact of heat recovery ventilators (HRVs) on the energy use and indoor radon in a one family detached house. Heat recovery ventilation systems, because of reducing ventilation loss through recovered exhaust air, can play a good role in the effectiveness of ventilation to reduce energy use. In addition HRVs can maintain pressure balance and outdoor ventilation rate at a required level to mitigate indoor radon level. Design/methodology/approach: In this study, a multizone model of a detached house is developed in IDA Indoor Climate and Energy (IDA ICE 4.0). The model is validated using measurements regarding use of energy for heating, ventilation and whole energy use. The performance of the heat recovery ventilation system is examined with respect to radon mitigation and energy saving by measuring the radon concentration and analyzing the life cycle cost of a heat exchanger unit. Findings: The results of the measurements and dynamic simulation showed that the heat recovery ventilation system could lead to 74 per cent energy savings of the ventilation loss, amounting to about 30 kWh m-2 per year. Life cycle cost analysis used for assessing total costs and the result showed that using this system is quite cost-effective and investment would payback during 12 years. Research limitations/implications: Limitations of this study generally refer to radon measurement and simulation because of radon complex behavior and its high fluctuations even during short periods of time. Practical implications: Heat recovery ventilation systems with reducing radon concentration improve indoor air quality and decrease environmental problems with energy savings. Social implications: Using balanced heat recovery ventilation can have benefits from the viewpoint of environmental impacts and household economy. Originality/value: Employment of a heat recovery unit to control indoor radon level is a new usage of this technology which along with energy savings can improve sustainable development.

  • 392.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Öman, Robert
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Impacts of heat recovery ventilators on energy savings and indoor radon in a Swedish detached house2013In: WSEAS Transactions on Environment and Development, ISSN 1790-5079, Vol. 9, no 1, p. 24-34Article in journal (Refereed)
    Abstract [en]

    Heat recovery ventilation systems, because of reducing ventilation loss through recovered exhaust air, can play a good role in the effectiveness of ventilation to reduce energy use. In this paper, the impact of a heat recovery ventilator (HRV) on the energy use and indoor radon in residential buildings is investigated. This paper describes the effects of a heat recovery ventilation system on energy consumption in a detached house in Stockholm, Sweden. The performance of the heat recovery ventilation system is examined with respect to radon mitigation and energy saving by measuring the radon concentration and analyzing the life cycle cost of a heat exchanger unit. In this study, a multizone model of a detached house is developed in IDA Indoor Climate and Energy (IDA ICE 4.0). The model is validated using measurements regarding use of energy for heating, ventilation and whole energy use. The results of the measurements and dynamic simulation showed that heat recovery ventilation system 74% energy savings of the ventilation loss, amounted about 30 kWh.m-2 per year. Life cycle cost analysis used for assessing total costs and the result showed that using this system is quite cost-effective and investment would payback during 12 years.

  • 393.
    Akbari, Keramatollah
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Öman, Robert
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Radon Mitigation using Heat Recovery Ventilation system in a Swedish Detached House2013In: WSEAS Transactions on Environment and Development, ISSN 1790-5079, Vol. 8, no 3, p. 73-82Article in journal (Refereed)
    Abstract [en]

    Balanced ventilation with heat recovery has strong effects on radon mitigation and energy saving in residential buildings. This new technology enables improvement of both indoor air quality and energy efficiency without sacrificing either. Reducing radon by means of forced ventilation requires an increase in outdoor supplied air (i.e. ventilation rate), which in turn can increase energy use. Energy losses in ventilation systems are inevitable, but new technologies such as heat recovery systems make it possible to recover most of this ventilation heat loss. Heat recovery ventilation systems, which recover energy from exhaust air, can significantly reduce ventilation losses, and balancing the indoor air pressure plays a positive role in the effectiveness of ventilation to reduce and mitigate radon levels and control indoor air quality. This paper describes a case study which considers the effects of a heat recovery ventilation system on the radon concentration and energy consumption in a detached house in Stockholm, Sweden. The performance of the heat recovery ventilation system is examined with respect to radon mitigation and energy saving by measuring the radon concentration and analyzing the life cycle cost in winter. The results of the measurements and dynamic simulation showed that a heat recovery ventilation system was able to reduce the radon level from around 600 Bq.m-3 to below 100 Bq.m-3 and reduce energy loss from ventilation by 80%, equivalent to around 3500 kWh per year. The results of life cycle cost analysis used to assess total costs showed that this system is cost-effective and investment would pay for itself in 12 years. It should be noted that this saving is a representative sample, and that actual savings would be influenced by a large number of factors. IDA 4.0 Indoor Climate and Energy software was used to perform the dynamic simulations.

  • 394.
    Akbari, N.
    et al.
    University of Tehran, Tehran, Iran.
    Modarressi, M.
    University of Tehran, Tehran, Iran.
    Daneshtalab, Masoud
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Royal Institute of Technology (KTH), Sweden.
    Loni, Mohammad
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Royal Institute of Technology (KTH), Sweden.
    A Customized Processing-in-Memory Architecture for Biological Sequence Alignment2018In: Proceedings of the International Conference on Application-Specific Systems, Architectures and Processors, Institute of Electrical and Electronics Engineers Inc. , 2018, article id 8445124Conference paper (Refereed)
    Abstract [en]

    Sequence alignment is the most widely used operation in bioinformatics. With the exponential growth of the biological sequence databases, searching a database to find the optimal alignment for a query sequence (that can be at the order of hundreds of millions of characters long) would require excessive processing power and memory bandwidth. Sequence alignment algorithms can potentially benefit from the processing power of massive parallel processors due their simple arithmetic operations, coupled with the inherent fine-grained and coarse-grained parallelism that they exhibit. However, the limited memory bandwidth in conventional computing systems prevents exploiting the maximum achievable speedup. In this paper, we propose a processing-in-memory architecture as a viable solution for the excessive memory bandwidth demand of bioinformatics applications. The design is composed of a set of simple and lightweight processing elements, customized to the sequence alignment algorithm, integrated at the logic layer of an emerging 3D DRAM architecture. Experimental results show that the proposed architecture results in up to 2.4x speedup and 41% reduction in power consumption, compared to a processor-side parallel implementation. 

  • 395.
    Akeza, Audrey
    et al.
    Mälardalen University, School of Health, Care and Social Welfare.
    Mossberg, Natalja
    Mälardalen University, School of Health, Care and Social Welfare.
    Att förebygga hypotermi hos vuxna patienter: En allmän litteraturöversikt2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 396.
    Akgüre, Elanur
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Dabiri, Shiva
    Mälardalen University, School of Innovation, Design and Engineering.
    Miljövänligare inflygningar2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

     Detta examensarbete handlar om miljövänligare inflygningar. Gröna- och kurvade inflygningar gör flyget mer miljövänligt. Det är ett effektivt sätt att minska flygets miljöpåverkan. Varje grön- och kurvad inflygning innebär minskad bränsleförbrukning, utsläpp samt betydligt lägre buller vid landning.

     Vid en grön inflygning, sjunker flygplanet kontinuerligt från sin marschhöjd till landningsbanan med motorerna på tomgång. En kurvad inflygning är en kombination av grön inflygning och kurvad inflygning. Med en kurvad inflygning kan man välja en väg där man inte flyger över bostadsområde. På så sätt blir det inga köbildningar i luften innan landningen. Vid kurvade inflygningar blir miljövinster större än med vanliga gröna inflygningar.

    För att ett flygplan skall kunna genomföra en grön inflygning krävs att det är utrustad med FMS (Flight Management System). Det är utrustning för navigering som bestämmer flygplants position genom att integrera navigationsuppgifter från en eller flera positionsgivare med information från flygplants fartmätar- och höjdmätarsystem.

    Flygvägar som SID och STAR skapar flygsäkerhet och ordning i luftrummet. SID är flygvägar för angående trafik och STAR är flygvägar för ankommande trafik. Syftet med P-RNAV STAR är att ett flygplan med navigeringsutrustning ska kunna programmera in färdvägen i sin FMS och på så sätt genomförs en optimal inflygning med låga koldioxidutsläpp.

    Gröna inflygningar har visat kunnat spara 100-150 kilo bränsle och 314-474 kilo koldioxidutsläpp vid varje miljövänlig inflygning beroende på flygplansmodell.

  • 397.
    Akhavan, Sharareh
    Mälardalen University.
    Arbetshälsa ur perspektiven klass, genus och etnicitet.2006In: I: Kors och tvärs: Intersektionalitet och makt i storstadens arbetsliv / [ed] Gunnarsson E., Neergard A., Nilsson A., Stockholm: Normal Förlag , 2006, p. 300-315Chapter in book (Other academic)
  • 398.
    Akhavan, Sharareh
    Mälardalen University, School of Health, Care and Social Welfare.
    Class, gender and ethnicity in relation to health care – A study on social disparities in the Swedish health care.2011In: Reconsidering social identification: race, gender, class and caste. / [ed] Janmohamed A. (Ed.), Routledge, 2011Chapter in book (Other academic)
  • 399.
    Akhavan, Sharareh
    Karolinska Institutet, Stockholm.
    Female Immigrants’ Health and Working Conditions in Sweden2007In: The international journal of diversity in organisations, communities and nations, ISSN 1447-9583, Vol. 7, no 2, p. 275-286Article in journal (Refereed)
    Abstract [en]

    Sweden is one of the European countries that has successively changed from a mainly ethnically homogeneous society into a multi-ethnic society. In 2001, almost 20 per cent of the Swedish population was classified as immigrants, i.e., they were either born abroad and naturalized, of foreign nationality or born in Sweden with at least one parent who had been born abroad. Reports, statistics and research have shown that the health of female immigrants is worse than that of the total population and that the incidence of long-term sickness absence and early retirement is higher in this group. The overall aim of this article is to describe, understand and analyze factors that contribute to poor health among female immigrants in Sweden from the perspective of class, gender and ethnicity. Being unemployed, on sick leave or working in occupation with low income and low status are examples that are related to class position, gender and ethnicity. The main three aspects based on class are wage, professional status and female immigrants position in the hierarchical work organisation. Other factors are discrimination due to ethnicity and gender, unfavourable physical and psychosocial work environment and absence of opportunities for skills upgrade training. Experiences of rape, domestic violence, unanswered emotional and sexual needs and patriarchal culture are examples that are related to gender. And experiencing traumatic events (in pre-migration periods such as experiences of war, prison, etc. and in post-migration periods such as experiences of discrimination and racism) are examples that are related to ethnicity.

  • 400.
    Akhavan, Sharareh
    Mälardalen University, School of Health, Care and Social Welfare.
    Invandrade kvinnors hälsa och arbetsvillkor i Sverige2011In: Perspektiv på kvinnors hälsa i arbetslivet / [ed] Sandmark H., Lund: Studentlitteratur, 2011, p. 135-142Chapter in book (Other academic)
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