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  • 151.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Data-driven rule mining and representation of temporal patterns in physiological sensor data2015In: IEEE journal of biomedical and health informatics, ISSN 2168-2194, E-ISSN 2168-2208, Vol. 19, no 5, 1557-1566 p.Article in journal (Refereed)
    Abstract [en]

    Mining and representation of qualitative patterns is a growing field in sensor data analytics. This paper leverages from rule mining techniques to extract and represent temporal relation of prototypical patterns in clinical data streams. The approach is fully data-driven, where the temporal rules are mined from physiological time series such as heart rate, respiration rate, and blood pressure. To validate the rules, a novel similarity method is introduced, that compares the similarity between rule sets. An additional aspect of the proposed approach has been to utilize natural language generation techniques to represent the temporal relations between patterns. In this study, the sensor data in the MIMIC online database was used for evaluation, in which the mined temporal rules as they relate to various clinical conditions (respiratory failure, angina, sepsis, ...) were made explicit as a textual representation. Furthermore, it was shown that the extracted rule set for any particular clinical condition was distinct from other clinical conditions.

  • 152.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Using Conceptual Spaces to Model Domain Knowledge in Data-to-Text Systems2014In: Proceedings of the 8th International Natural Language Generation Conference, Association for Computational Linguistics, 2014, 11-15 p.Conference paper (Refereed)
    Abstract [en]

    This position paper introduces the utilityof the conceptual spaces theory to conceptualisethe acquired knowledge in data-totextsystems. A use case of the proposedmethod is presented for text generationsystems dealing with sensor data. Modellinginformation in a conceptual spaceexploits a spatial representation of domainknowledge in order to perceive unexpectedobservations. This ongoing work aimsto apply conceptual spaces in NLG forgrounding numeric information into thesymbolic representation and confrontingthe important step of acquiring adequateknowledge in data-to-text systems.

  • 153.
    Bandaru, Vamsi Krishna
    et al.
    Örebro University, School of Science and Technology.
    Balasubramanian, Rajasekaran
    Örebro University, School of Science and Technology.
    OBJECT RECOGNITION USINGDIALOGUES AND SEMANTICANCHORING2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report explains in detail the implemented system containing a robot and a sensor

    network that is deployed in a test apartment in an elderly residence area. The report

    focuses on the creation and maintenance (anchoring) of the connection between the

    semantic information present in the dialog with perceived actual physical objects in the

    home. Semantic knowledge about concepts and their correlations are retrieved from online

    resources and ontologies, e.g. Word-Net and sensors information are provided by

    cameras distributed in the apartment.

  • 154.
    Banjop Kharlyngdoh, Joubert
    Örebro University, School of Science and Technology.
    Modulation of androgen receptor function by brominated flame retardants2015Doctoral thesis, comprehensive summary (Other academic)
    List of papers
    1. Identification of a group of brominated flame retardants as novel androgen receptor antagonists and potential neuronal and endocrine disrupters
    Open this publication in new window or tab >>Identification of a group of brominated flame retardants as novel androgen receptor antagonists and potential neuronal and endocrine disrupters
    Show others...
    2015 (English)In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 74, 60-70 p.Article in journal (Refereed) Published
    Abstract [en]

    Brominated flame-retardants (BFRs) are used in industrial products to reduce the risk of fire. However, their continuous release into the environment is a concern as they are often persistent, bioaccumulating and toxic. Information on the impact these compounds have on human health and wildlife is limited and only a few of them have been identified to disrupt hormone receptor functions. In the present study we used in silico modeling to determine the interactions of selected BFRs with the human androgen receptor (AR). Three compounds were found to dock into the ligand-binding domain of the human AR and these were further tested using in vitro analysis. Allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) were observed to act as AR antagonists. These BFRs have recently been detected in the environment, in house dust and in aquatic animals. The compounds have been detected at high concentrations in both blubber and brain of seals and we therefore also assessed their impact on the expression of L-type amino acid transporter system (LAT) genes, that are needed for amino acid uptake across the blood-brain barrier, as disruption of LAT gene function has been implicated in several brain disorders. The three BFRs down-regulated the expression of AR target genes that encode for prostate specific antigen (PSA), 5. α-reductases and β-microseminoprotein. The potency of PSA inhibition was of the same magnitude as the common prostate cancer drugs, demonstrating that these compounds are strong AR antagonists. Western blot analysis of AR protein showed that ATE, BATE and DPTE decreased the 5. α-dihydrotestosterone-induced AR protein levels, further confirming that these BFRs act as AR antagonists. The transcription of the LAT genes was altered by the three BFRs, indicating an effect on amino-acid uptake across cellular membranes and blood-brain barrier. This study demonstrated that ATE, BATE and DPTE are potent AR antagonists and the alterations in LAT gene transcription suggest that these compounds can affect neuronal functions and should be considered as potential neurotoxic and endocrine disrupting compounds.

    Keyword
    Gene regulation; Human; PSA; LAT
    National Category
    Environmental Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-41508 (URN)10.1016/j.envint.2014.09.002 (DOI)000346681700008 ()25454221 (PubMedID)2-s2.0-84908626070 (Scopus ID)
    Funder
    Knowledge Foundation, 20110183
    Note

    Funding Agency:

    Örebro University J61900

    Available from: 2015-01-14 Created: 2015-01-14 Last updated: 2017-12-05Bibliographically approved
    2. The brominated flame retardant TBECH activates the zebrafish (Danio rerio) androgen receptor, alters gene transcription and causes developmental disturbances
    Open this publication in new window or tab >>The brominated flame retardant TBECH activates the zebrafish (Danio rerio) androgen receptor, alters gene transcription and causes developmental disturbances
    2013 (English)In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 142, 63-72 p.Article in journal (Refereed) Published
    Abstract [en]

    Tetrabromoethylcyclohexane (TBECH) is a brominated flame retardant that has been shown to be a potent agonist to the human androgen receptor (AR). However, while it is present in the environment, it is not known if it interacts with AR from aquatic species. The present study was therefore aimed at improving our understanding of how TBECH affects aquatic animals using zebrafish as a model organism. In silica modeling demonstrated that TBECH diastereomers bind to the zebrafish androgen receptor (zAR) and in vitro and in vivo data showed that TBECH has androgenic properties. Deleterious effects of TBECH were studied on embryonic and juvenile zebrafish and qRT-PCR analysis in vitro and in vivo was performed to determine TBECH effects on gene regulation. TBECH was found to delay hatching at 1 mu M and 10 mu M doses while morphological abnormalities and juvenile mortality was observed at 10 mu M. The qRT-PCR analysis showed alterations of multiple genes involved in chondrogenesis (cartilage development), metabolism and stress response. Thus, TBECH induces androgenic activity and has negative effects on zebrafish physiology and therefore its impact on the environment should be carefully monitored. (C) 2013 Elsevier B.V. All rights reserved.

    Keyword
    Androgens, Endocrine, Endocrine disruptor, Gene regulation
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:oru:diva-32902 (URN)10.1016/j.aquatox.2013.07.018 (DOI)000328093900007 ()23958786 (PubMedID)
    Funder
    Knowledge Foundation
    Available from: 2014-01-02 Created: 2014-01-02 Last updated: 2017-12-06Bibliographically approved
    3. Androgen receptor mutations associated with prostate cancer lead to differential activation by DBE-DBCH diastereomers
    Open this publication in new window or tab >>Androgen receptor mutations associated with prostate cancer lead to differential activation by DBE-DBCH diastereomers
    (English)Manuscript (preprint) (Other academic)
    Keyword
    steroid hormone receptor, endocrine disruptor, human carcinoma, androgen agonists
    National Category
    Biological Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-44665 (URN)
    Available from: 2015-05-20 Created: 2015-05-20 Last updated: 2017-10-17Bibliographically approved
    4. Combination effects on human cell lines following exposure to brominated flame-retardants that interact with the androgen receptor
    Open this publication in new window or tab >>Combination effects on human cell lines following exposure to brominated flame-retardants that interact with the androgen receptor
    (English)Manuscript (preprint) (Other academic)
    Keyword
    DBE-DBCH/TBECH, TBP-AE/ATE, TBP-BAE/BATE, TBP-DBPE/DPTE, endocrine disruptors, PSA, steroidogenesis
    National Category
    Biological Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-44666 (URN)
    Available from: 2015-05-20 Created: 2015-05-20 Last updated: 2017-10-17Bibliographically approved
  • 155.
    Banjop Kharlyngdoh, Joubert
    et al.
    Örebro University, School of Science and Technology.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Combination effects on human cell lines following exposure to brominated flame-retardants that interact with the androgen receptorManuscript (preprint) (Other academic)
  • 156.
    Banjop Kharlyngdoh, Joubert
    et al.
    Örebro University, School of Science and Technology.
    Pradhan, Ajay
    Örebro University, School of Science and Technology.
    Asnake, Solomon
    Örebro University, School of Science and Technology.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Androgen receptor mutations associated with prostate cancer lead to differential activation by DBE-DBCH diastereomersManuscript (preprint) (Other academic)
  • 157.
    Banjop-Kharlygdoh, Joubert
    et al.
    Örebro University, School of Science and Technology.
    Pradhan, Ajay
    Örebro University, School of Science and Technology.
    Asnake, Solomon
    Örebro University, School of Science and Technology.
    Walstad, Anders
    Örebro University, School of Science and Technology.
    Ivarsson, Per
    ALS Laboratory Group, Analytical Chemistry & Testing Services, Stockholm, Sweden.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Identification of a group of brominated flame retardants as novel androgen receptor antagonists and potential neuronal and endocrine disrupters2015In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 74, 60-70 p.Article in journal (Refereed)
    Abstract [en]

    Brominated flame-retardants (BFRs) are used in industrial products to reduce the risk of fire. However, their continuous release into the environment is a concern as they are often persistent, bioaccumulating and toxic. Information on the impact these compounds have on human health and wildlife is limited and only a few of them have been identified to disrupt hormone receptor functions. In the present study we used in silico modeling to determine the interactions of selected BFRs with the human androgen receptor (AR). Three compounds were found to dock into the ligand-binding domain of the human AR and these were further tested using in vitro analysis. Allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) were observed to act as AR antagonists. These BFRs have recently been detected in the environment, in house dust and in aquatic animals. The compounds have been detected at high concentrations in both blubber and brain of seals and we therefore also assessed their impact on the expression of L-type amino acid transporter system (LAT) genes, that are needed for amino acid uptake across the blood-brain barrier, as disruption of LAT gene function has been implicated in several brain disorders. The three BFRs down-regulated the expression of AR target genes that encode for prostate specific antigen (PSA), 5. α-reductases and β-microseminoprotein. The potency of PSA inhibition was of the same magnitude as the common prostate cancer drugs, demonstrating that these compounds are strong AR antagonists. Western blot analysis of AR protein showed that ATE, BATE and DPTE decreased the 5. α-dihydrotestosterone-induced AR protein levels, further confirming that these BFRs act as AR antagonists. The transcription of the LAT genes was altered by the three BFRs, indicating an effect on amino-acid uptake across cellular membranes and blood-brain barrier. This study demonstrated that ATE, BATE and DPTE are potent AR antagonists and the alterations in LAT gene transcription suggest that these compounds can affect neuronal functions and should be considered as potential neurotoxic and endocrine disrupting compounds.

  • 158.
    Bao, Jia
    et al.
    Shenyang Univ Technol, Sch Sci, Shenyang 110870, Peoples R China ; Univ Örebro, Man Technol Environm MTM Res Ctr, Örebro, Sweden.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Jin, Yihe
    Dalian Univ Technol, Sch Environm Sci & Technol, Key Lab Ind Ecol & Environm Engn MOE, Dalian 116024, Peoples R China.
    Perfluoroalkyl substances in the blood samples from a male population of Sweden2014In: Chinese Science Bulletin, ISSN 1001-6538, E-ISSN 1861-9541, Vol. 59, no 4, 388-395 p.Article in journal (Refereed)
    Abstract [en]

    Temporal trends of perfluoroalkyl substances (PFASs) have been determined in the blood samples from several countries globally including a female population in Sweden recently, yet little is known about the time trends in the blood levels of these compounds in Swedish male populations over recent years. In this study, the fourteen target PFASs consisted of four perfluorosulfonates (PFSAs) and ten perfluorocarboxylates (PFCAs) in the whole blood samples, collected from 153 Swedish elderly men during the period between 2008 and 2010, were analyzed via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). As the dominant PFASs contaminants in the blood samples, perfluorooctane sulfonate (PFOS) showed the highest geometric mean (GM) at 8.5 ng/mL, ranging from 1.7 to 29 ng/mL, while blood perfluorooctanoic acid (PFOA) contained the GM of 1.8 ng/mL, ranging from 0.35 to 6.4 ng/mL. Both the levels of these two compounds were lower than those determined in the blood samples of Swedish elderly populations derived from the late 1990s. According to the temporal trend analysis, over the three years, the blood levels of PFOS in Swedish male populations declined 16 % per annum, while those of perfluoroundecanoic acid (PFUnDA) increased 6.1 % per annum, which were consistent with those reported previously for the populations from other countries.

  • 159.
    Barbaranelli, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Bengtsson, Pär
    Örebro University, School of Science and Technology.
    KOLFIBERFÖRSTÄRKNING – En jämförelse mellan kolfiberförstärkning och traditionella förstärkningsmetoder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A building part could need a reinforcement. It could be a system of joists that are soon going to be loaded with heavier loads when business is changing from residence to an office. The alternate solution to reinforce that kind of construction would be with steel beams and columns or increase the height of the floor with more concrete. What few constructors and contractors know are the solution with carbon fiber reinforcement could be a better alternative.

    The purpose of the thesis is to study if carbon fiber reinforcement could compete with traditional reinforcement methods. From a calculating and a work-related perspective the project will underline the pro and cons with all of the reinforcement methods. To demonstrate how carbon fiber increase the bending moment capacity have lab and calculation of a real bridge project been executed. In both cases have a carbon fiber solution been compared with traditional reinforcement methods.

    The result of the thesis shows that carbon fiber reinforcement could replace traditional methods in many cases. The pros with the carbon fiber reinforcement is the light weight and high tensile strength that makes it possible, on an efficient way, increase the bending moment capacity in a building part. The thesis lab result shows that a carbon fiber reinforcement does have the same percentage increase in strength as a flat steel reinforcement.

  • 160.
    Bark, Alexander
    et al.
    Örebro University, School of Science and Technology.
    Hygerth, Fredrik
    Örebro University, School of Science and Technology.
    Söka en signifikant skillnad huruvida skadeutvecklingen skiljer mellan punktlast och utbredd last inom pappersteknik2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thesis work performed on behalf of BillerudKorsnäs AB, the project is part of a larger research project which the company works with. BillerudKorsnäs would like to provide the optimum material for the cartonboard that the customer seeks. This report deals with the problem of whether the fracture development differs between the point load and distributed load in paper technology. To limit the scope of the project, five spherical loads were chosen to attack a total of four selected panels. The four panels are specifically selected and divided into two geometrically distinct cartonboards but with the same quality. The project investigated parameters structural stiffness and structural strength from the unloaded condition to initial damage development in cartonboards. The results from the tests will be presented inaquantitative analysis of compiled charts, force-/extension charts and qualitative analysis of fracture development. The purpose of the project, the significant difference, was found in the result when the structural stiffness increased nonlinearly when tested with certain loads. The project presents a conclusion that the load 1-3 is point load and load 5 is distributed load on all panels. The project presents a basis for further development towards the final goal that BillerudKorsnäs is working toward.

  • 161.
    Bark, Daniel
    Örebro University, School of Science and Technology.
    FRAMTAGNING AV GITARRFÖRSTÄRKARBYGGSATS2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Nobody sells guitar amplifier assembly kits in Sweden. This report will take you all the way from a request, to a complete prototype of a guitar amplifier. A guitar amplifier that will be sold as an assembly kit.

    A company in the south of Sweden that sells guitar effect assembly kits requested a bachelors dissertation where a student would design a guitar amp. The amp should be as simple as possible, but be able to deliver 5 Watts. This was a very tempting offer for me, a student at the sound engineering program, who loves everything related to guitars.

    In the report we will talk about the fundamental parts in a guitar amp. Keep in mind that this is a technical report. The report will not contain long subjective statements about what sound good or bad in my ears. I will begin with putting together a technical specification while considering the needs of the requesting company. Thereafter I will reason my way to a simple circuit containing 3 stages of amplification, based on vacuum tubes. I will design a chassis that will allow me to successfully build a functioning prototype that will meet the specifications I got from the company.

  • 162.
    Barsom, Daniella
    et al.
    Örebro University, School of Science and Technology.
    Osama, Rand
    Örebro University, School of Science and Technology.
    EFFEKTIVISERING AV DELMOMENT I PROCESSKARTLÄGGNING2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis involves a process mapping to the rebuilding of the gymnasium of Vivallaskolan that burned down at the end of October 2010. Analyses and observations in the activity flow are based on the process mapping. There it shows what subsection that has gone well and less well. Suggested solutions have been made to the problems that gone less well. These solutions show clearly how they can be improved and are based on the following methods: the PDCA-cycle (page 21), BIM (page 21) and Ishikawa diagrams (page 21).

    This process mapping and suggested solutions are based on observations at the construction site together with reading literature and electronic sources. During visits and conversations with the construction manager and carpenters it have been recognized that Lean, which is a method for efficiency of different activity flows, are already partially used in the production of this construction project. These suggested solutions have been made to improve and develop the production phase qualitatively.

    During the survey and analysis of the process mapping, those who are involved in this construction project can clearly see and follow these suggested solutions. These are made to avoid upcoming problems which have been described in this thesis. These solutions can be used to upcoming construction projects already at the designing and calculation phase.

  • 163.
    Barton, Jakob
    et al.
    Örebro University, School of Science and Technology.
    Rödjemyr, Gustav
    Örebro University, School of Science and Technology.
    En undersökning av prefabricerade och platsbyggda utfackningsväggar2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    NCC – Nordic Construction Company – in Örebro has recently decided to use prefabricated

    infill-walls as a method of choice. This report aims to explore, compile and compare the

    method of prefabricating infill-walls with the method of building infill-walls on site. The

    comparison has been made through considering aspects such as work environment, time

    consummation, manufacturing and production costs.

    The report has been conducted upon request from NCC in order to provide an indication of

    which method of production that present the best alternative for future projects. Interviews

    and information from relevant and ongoing projects in the Örebro area constitutes the basis of

    this report. All references to costs and time are based upon actual time schemes and invoices

    collected from said projects. The work environment has been compared to the risk analysis

    made by responsible staff members on site, all in accordance with the Swedish Work

    Environment Authority’s (Arbetsmiljöverket) directives. According to this report the

    difference in financial terms between site build and infill-walls is not that big. By using

    prefabricated infill-walls the report shows that you can save a lot of time. The report has been

  • 164.
    Basic, Mehmed
    Örebro University, School of Science and Technology.
    Specifikation av OP-tid (Operation Time)2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this technical thesis is to investigate different methods and tools to measure the OP time (operating time). Ericsson is headquartered in Stockholm,and is divided into different departments, these department’s together has approximately 10 000 employees who is specializedin their areas. The focus of this technical report has been to investigate the questions like, what is OP time, is there a way to measure the OP time.The Department that is the focus of this project produces filters for radio base stations. This should be viewed both from a financial and engineering perspective. This examine will give an explanation on what the OP time is in a test lab environment and to give suggestions on how to measure the OP time. Time is money which means that a separation between OP time and other time will lower the unnecessary costs. By establishing "clean" OP time apart from other time, obtains the actual cost of the product. In theory section Lean production and JIT (just in time) and its grounds will be described. The idea is to compare a volume business with a prototype business, and thereafter focus on the prototype business, specifically on its problem areas and solutions.

  • 165.
    Basic, Vladimir T.
    et al.
    Department of Clinical Medicine, Örebro University, Örebro, Sweden.
    Jacobsen, Annette
    Department of Clinical Medicine, Örebro University, Örebro, Sweden; School of Biomedical Sciences, Charles Sturt University, WaggaWagga, Australia.
    Tadele, Elsa
    Department of Clinical Medicine, Örebro University, Örebro, Sweden; Medical University of Giessen, Molecular Biology and Medicine of the Lung program, Giessen, Germany.
    Banjop- Kharlyngdoh, Joubert
    Örebro University, School of Science and Technology.
    Sirsjö, Allan
    Department of Clinical Medicine, Örebro University, Örebro, Sweden.
    Abdel-Halim, Samy M.
    Division of Respiratory Medicine and Allergology, Department of Clinical Sciences, Danderyd Hospital, Stockholm, Sweden.
    Cigarette smoke exposure up-regulates Ubiquitin specific protease 19 in murine skeletal muscles as an adaptive response to prolonged ER stressManuscript (preprint) (Other academic)
    Abstract [en]

    Enhanced protein degradation via ubiquitin proteolytic system (UPS) was demonstrated to play an important role in the pathogenesis of cachexia syndrome and muscle wasting in patients with COPD and animal models of the disease. The role of cigarette smoke (CS) exposure in eliciting these abnormalities remains largely unknown. Usp19 is a member of UPS suggested to be involved in progressive muscle wasting in different catabolic conditions. However, factors regulating Usp19 expression, activity and correlation/s with CS-induced muscle atrophy remainunclear.

    Methods: To address these questions, 129 SvJ mice were exposed to cigarette smoke for 6 months and the gastrocnemius muscles were collected. Expression levels of Usp19 as well as pivotal mediators of ER stress response have been studied using PCR, qPCR, western blot and immunofluorescence. Factors regulating muscle Usp19 expression were studied using in-silico analysis of Usp19 promoter as well as by stimulating C2C12 myocytes with different inducers of ER stress including hypoxia, TNF and tunicamycin. Finally, Usp19 expression was depleted in C2C12 myocytes using specific Usp19 siRNA quadriplex and the expression of pivotal myogenic regulators were analyzed.

    Results: Usp19 mRNA expression was enhanced in skeletal muscles of CS-exposed mice. Concurrently, ER stress-associated Caspase 12 and Caspase 3 were activated in the CS-exposed group. Analysis of Usp19 promoter sequence revealed binding sites for ER stress response transcription factors such as HSF, STRE1 and AML1-α. Exposure of C2C12 myocytes to tunicamycin but not hypoxia elevated expression levels of Usp19. TNFstimulation elevated Usp19 protein expression but inhibited its RNA transcription in a dose- and time-dependent manner. Finally, Usp19 overexpression in tunicamycin-treated myocytes was accompanied by reduced expression of myosin heavy chain and tropomyosin and their levels were increased after knocking down Usp19 in C2C12 myocytes.

    Conclusions: In summary, our data demonstrated elevated expression of Usp19 in skeletal muscles of CS-exposed 129 SvJ mice. Moreover, Usp19 overexpression was associated with muscle adaptations to ER stress and suppression of myogenesis. Taken together; our results might provide further insight into molecular mechanisms underlying development and progression of skeletal muscle abnormalities in response to chronic cigarette smoke exposure.

  • 166.
    Bayayibign, Biruhalem Assefa
    Örebro University, School of Science and Technology.
    Effect of oxidative stress on tryptophan and tyrosine uptake in cultured human fibroblasts: the  role of α tocotreinol: Oxidative stress and amino acid uptake2012Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Aberrant transport of tryptophan and tyrosine is implicated in abnormal dopaminergic and serotoninergic transmissions in psychiatric disorders. Disturbed transport of tyrosine is a repeated finding in cultured fibroblasts from psychiatric patients. The causes for the aberrant transport are not clearly defined yet, but a general membrane dysfunction and altered amino acid transport in psychiatric patients are suggested as major factors. Cellular macromolecules (for example, membrane proteins and lipids) damage associated with oxidative stress are common phenomena in psychiatric patients and antioxidants are proven to be effective in the management of certain psychiatric disorders as therapeutic adjutants. Moreover, oxidative stress has been reported to inhibit the uptake of amino acids in vitro that can be reversed by the application of antioxidants. The aims of the present study were to assess the effect of hydrogen peroxide (H2O2) on tryptophan and tyrosine uptake, and to further investigate the role of α-tocotrienol in counteracting the effect of H2O2 on tryptophan and tyrosine uptake in cultured fibroblasts. Fibroblasts from a healthy control were treated with H2O2, α-tocotrienol and H2O2 and α-tocotrienol together, and the uptake of L-[14C] tyrosine and L-[3H] tryptophan was determined by using the cluster tray technique. Treatment of fibroblasts with H2O2 significantly (P<0.05) inhibited tyrosine uptake (15.4% inhibition), and the inhibition was prevented by the application of α-tocotrienol. The same treatment conditions did not affect the uptake of tryptophan at the specific tryptophan concentration used for the uptake assay in this study. The results of this study suggest that oxidative stress could be a cause for the aberrant tyrosine transport in fibroblasts from different psychiatric patients and provide a potential mechanism of action for antioxidants used in the treatment of psychiatric disorders; further studies are required to understand the role of oxidative stress on amino acid transporters.

  • 167.
    Bazzan, Ana L. C.
    et al.
    Instituto de Informática/PPGC, UFRGS, Porto Alegre, RS, Brazil.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    A review on agent-based technology for traffic and transportation2014In: Knowledge engineering review (Print), ISSN 0269-8889, E-ISSN 1469-8005, Vol. 29, no 3, 375-403 p.Article, review/survey (Refereed)
    Abstract [en]

    In the last few years, the number of papers devoted to applications of agent-based technologies to traffic and transportation engineering has grown enormously. Thus, it seems to be the appropriate time to shed light over the achievements of the last decade, on the questions that have been successfully addressed, as well as on remaining challenging issues. In the present paper, we review the literature related to the areas of agent-based traffic modelling and simulation, and agent-based traffic control and management. Later we discuss and summarize the main achievements and the challenges.

  • 168.
    Beeson, Patrick
    et al.
    TRACLabs Inc., USA.
    Kortenkamp, David
    TRACLabs Inc., USA.
    Bonasso, R. Peter
    TRACLabs Inc., USA.
    Persson, Andreas
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Bona, Jonathan P
    State University of New York, Buffalo, USA.
    An Ontology-Based Symbol Grounding System for Human-Robot Interaction2014In: Artificial Intelligence for Human-Robot Interaction: 2014 AAAI Fall Symposium, AAAI Press, 2014Conference paper (Refereed)
    Abstract [en]

    This paper presents an ongoing collaboration to develop a perceptual anchoring framework which creates and maintains the symbol-percept links concerning household objects. The paper presents an approach to non-trivialize the symbol system using ontologies and allow for HRI via enabling queries about objects properties, their affordances, and their perceptual characteristics as viewed from the robot (e.g. last seen). This position paper describes in brief the objective of creating a long term perceptual anchoring framework for HRI and outlines the preliminary work done this far.

  • 169. Beetz, Michael
    et al.
    Chatila, Raja
    Hertzberg, Joachim
    Pecora, Federico
    Örebro University, School of Science and Technology.
    AI Reasoning Methods for Robotics2016In: Springer Handbook of Robotics / [ed] Bruno Siciliano, Oussama Khatib, Springer, 2016, 2, 329-356 p.Chapter in book (Other academic)
    Abstract [en]

    Artificial intelligence (AI) reasoning technology involving, e.g., inference, planning, and learning, has a track record with a healthy number of successful applications. So can it be used as a toolbox of methods for autonomous mobile robots? Not necessarily, as reasoning on a mobile robot about its dynamic, partially known environment may differ substantially from that in knowledge-based pure software systems, where most of the named successes have been registered. Moreover, recent knowledge about the robot’s environment cannot be given a priori, but needs to be updated from sensor data, involving challenging problems of symbol grounding and knowledge base change. This chapter sketches the main robotics relevant topics of symbol-based AI reasoning. Basic methods of knowledge representation and inference are described in general, covering both logic and probability-based approaches. The chapter first gives a motivation by example, to what extent symbolic reasoning has the potential of helping robots perform in the first place. Then (Sect. 14.2), we sketch the landscape of representation languages available for the endeavor. After that (Sect. 14.3), we present approaches and results for several types of practical, robotics-related reasoning tasks, with an emphasis on temporal and spatial reasoning. Plan-based robot control is described in some more detail in Sect. 14.4. Section 14.5 concludes.

  • 170.
    Beiruti, Michel
    Örebro University, School of Science and Technology.
    OPTIMERING VID VAL AV BJÄLKLAGSTYP2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 171.
    Belew, Yeshiwas Ayalneh
    Örebro University, School of Science and Technology.
    Consequence of Sun Exposure on the Level of Urinary Thymine Dimer and the Modulating Effect of Sunscreen2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Solar ultraviolet radiation (UVR) absorbed by the human skin cells can cause DNA lesions and formation of those is linked to development of skin cancer. Cylobutane thymine dimer (T=T) is one of the predominant lesions which is excreted in the urine after repair in skin cells. Urinary T=T can be used as a biomarker of exposure to UVR. The aim of this study was to determine the impact of UVR on urinary T=T levels in individuals before and after one week at the island Tenerife and to compare the protective effect of sunscreen in two groups, i.e. group (A) of 12 persons who had to use sunscreen as instructed and group (B) of 11 persons who were not instructed to use sunscreen. Furthermore, the association between T=T levels and other parameters such as standard erythemal dose, pigment protection factor, time spent outdoors and serum vitamin D level was investigated. Urinary T=T was analysed with the 32P-postlabelling assay. T=T could not be detected in samples collected before going to Tenerife, but after returning from the island the levels were increased in a rage of 27 to 804 fmol/μmol creatinine (mean 140 and 180 fmol/μmol creatinine for group A and B, respectively). There was no significant difference in T=T levels between the two study groups (p = 0.82). The hypothesis was that T=T levels for group B would be higher than for group A and the reason for not finding that is unknown but could simply be due to the low number of participants. No significant correlations were observed between T=T level and other  parameters, except for T=T with time spent outdoors, with a negative correlation which can not be explained. In conclusion, UVR exposure induces DNA damage in exposed humans that is measurable as increased T=T levels in urine.

  • 172.
    Belfrage, Kristina
    et al.
    Department of Urban and Rural Development, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Björklund, Johanna
    Örebro University, School of Science and Technology.
    Salomonsson, Lennart
    Department of Urban and Rural Development, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Effects of farm size and on-farm landscape heterogeneity on biodiversity-case study of twelve farms in a swedish landscape2015In: Agroecology and Sustainable Food Systems, ISSN 2168-3565, E-ISSN 2168-3573, Vol. 39, no 2, 170-188 p.Article in journal (Refereed)
    Abstract [en]

    In this study in Sweden, six small (<50 ha) and six large farms (>135 ha) participated. The aims of the study were to a) measure differences between small and large farms regarding on-farm landscape heterogeneity, and b) evaluate relations between on-farm landscape heterogeneity and biodiversity, measured as numbers of breeding bird species, bird territories, butterflies, bumblebees, and herbaceous plant species. Sample area of the same size, placed on each farm, was used for the biodiversity assessments and on-farm landscape heterogeneity studies. On-farm landscape heterogeneity was classified with the Shannon-Wiener diversity index. Linear regression was applied to analyze relationships between on-farm landscape heterogeneity and biodiversity indicators. Multivariate regression was used to analyze relations between single bird species and specific on-farm habitats. Small farms had significantly higher on-farm landscape heterogeneity than large farms. Strong positive relations between on-farm landscape heterogeneity and number of breeding birds, butterflies, and herbaceous plant species were found. Total on-farm landscape heterogeneity seems to be more important for bird diversity than do specific landscape elements. The study indicates that, to increase biodiversity, farm size should be taken into consideration.

  • 173.
    Bengtsson, Per
    et al.
    Örebro University, School of Science and Technology.
    Fransson, Martin
    Örebro University, School of Science and Technology.
    Ställtidsreducering vid orderbyte: En fallstudie på Millcon AB2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Millcon AB is a company that performs a service which is roll converting of paper. The company has recently noticed that their production waste a lot of time between orders due to mandatory setup activities, when a change of order in their rolling machines needs to be done. This leads to reduced production, which consequently contributes to reduced profitability for the company. This thesis will generate comprehensive data consisting of suggestions for improvement for the company to reduce setup time at one of their machines, but the suggestions for improvement can be used on all the machines that the company possess if certain modifications are made. The SMED method has been the main basis of the literature study which have been required to accomplish this thesis. The thesis began with a survey of how the conversion work is carried out at the present time, the survey was done with the help of video filming and interviews. Then several improvements which consisted of various opportunities to improve efficiency of the conversion process was made. The thesis concludes with a discussion of whether the streamlining suggestions that emerged are credible to generate a more time efficient approach for the company’s setup activities. The discussion then results in a number of finding conclusions, the conclusions are expected to provide Millcon a basis for their further improvement of their setup activities between orders.

  • 174.
    Bennetts, Victor Hernandez
    et al.
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Robot Assisted Gas Tomography - Localizing Methane Leaks in Outdoor Environments2014In: 2014 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), IEEE conference proceedings, 2014, 6362-6367 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we present an inspection robot to produce gas distribution maps and localize gas sources in large outdoor environments. The robot is equipped with a 3D laser range finder and a remote gas sensor that returns integral concentration measurements. We apply principles of tomography to create a spatial gas distribution model from integral gas concentration measurements. The gas distribution algorithm is framed as a convex optimization problem and it models the mean distribution and the fluctuations of gases. This is important since gas dispersion is not an static phenomenon and furthermore, areas of high fluctuation can be correlated with the location of an emitting source. We use a compact surface representation created from the measurements of the 3D laser range finder with a state of the art mapping algorithm to get a very accurate localization and estimation of the path of the laser beams. In addition, a conic model for the beam of the remote gas sensor is introduced. We observe a substantial improvement in the gas source localization capabilities over previous state-of-the-art in our evaluation carried out in an open field environment.

  • 175.
    Beno, Tomas
    et al.
    Högskolan Väst.
    Repo, Jari
    Högskolan Väst.
    Pejryd, Lars
    Örebro University, School of Science and Technology.
    The use of machine tool internal encoders as sensors in a process monitoring system2013In: International Journal of Automation Technology, ISSN 1881-7629, E-ISSN 1883-8022, Vol. 7, no 4, 410-417 p.Article in journal (Refereed)
    Abstract [en]

    Tool wear in machining changes the geometry of the cutting edges, which affects the direction and amplitudes of the cutting force components and the dynamics in the machining process. These changes in the forces and dynamics are picked up by the internal encoders and thus can be used for monitoring of changes in process conditions. This paper presents an approach for the monitoring of amulti-toothmilling process. The method is based on the direct measurement of the output from the position encoders available in the machine tool and the application of advanced signal analysis methods. The paper investigates repeatability of the developed method and discusses how to implement this in a process monitoring and control system. The results of this work show that various signal features which are correlated with tool wear can be extracted from the first few oscillating components, representing the low-frequency components, of the machine axes velocity signatures. The responses from the position encoders exhibit good repeatability, especially short term repeatability while the long-term repeatability is more unreliable.

  • 176.
    Berg, Håkan
    et al.
    Örebro University, School of Science and Technology. Marine Science Institute, University of Texas at Austin, United States .
    Rice, Charles
    Department of Biology, Clemson University, United States .
    Rahman, Saydur
    Marine Science Institute, University of Texas at Austin, United States .
    Dong, Jing
    Marine Science Institute, University of Texas at Austin, United States .
    Thomas, Peter
    Marine Science Institute, University of Texas at Austin, United States .
    Identification and characterization of membrane androgen receptors in the ZIP9 zinc transporter subfamily: I. Discovery in female Atlantic croaker and evidence ZIP9 mediates testosterone-induced apoptosis of ovarian follicle cells2014In: Endocrinology, ISSN 0013-7227, E-ISSN 1945-7170, Vol. 155, no 11, 4237-4249 p.Article in journal (Refereed)
    Abstract [en]

    Rapid, cell surface-initiated, pregenomic androgen actions have been described in various vertebrate cells, but the receptors mediating these actions remain unidentified.We report here cloning and expression of a cDNA from Atlantic croaker (Micropogonias undulatus) ovaries encoding a 33kDa, 7-transmembrane protein with binding and signaling characteristics of a membrane androgen receptor (mAR) that is unrelated to any previously described steroid receptor. Instead croaker mAR has 81–93 % amino acid sequence identity with zinc transporter ZIP9 (SLC39A9) subfamily members, indicating it is a ZIP9 protein. Croaker ZIP9 is expressed in gonadal tissues and in brain, and is upregulated in the ovary by reproductive hormones. ZIP9 protein is localized to plasma membranes of croaker granulosa cells and human breast cancer (SKBR-3) cells stably transfected with ZIP9. Recombinant croaker ZIP9 has a high affinity (Kd 12.7 nM), limited capacity (Bmax 2.8nM/mgprotein), displaceable, single binding site specific for androgens, characteristic of steroid receptors. Testosterone activates a stimulatory G protein coupled to ZIP9, resulting in increased cAMP production. Testosterone promotes serum starvation-induced cell death and apoptosis in transfected cells and in croaker ovarian follicle cells that is associated with rapid increases in intracellular free zinc concentrations, suggesting an involvement of zinc in this nonclassical androgen action to promote apoptosis. These responses to testosterone are abrogated by treatment with ZIP9 siRNA. The results provide the first evidence that zinc transporter proteins can function as specific steroid membrane receptors and indicate a previously unrecognized signaling pathway mediated by steroid receptors involving alterations in intracellular zinc.

  • 177.
    Berg, Isabelle
    Örebro University, School of Science and Technology.
    Validation of MP-AES at the Quantification of Trace Metals in Heavy Matrices with Comparison of Performance to ICP-MS2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The MP-AES 4200 using microwave plasma and an atomic emission spectroscopy detector provide a new and improved instrument to the analytical field. In this project will the performance of the equipment be evaluated in controlled NaCl-heavy matrices for selected metals (Cu, Zn, Li) and the result from this will be used to optimize a method for specific samples. These samples consist of combustion ashes from the incineration of hazardous waste and are provided by the company SAKAB AB. The sample preparation consisted of several cycles of L/S 10 followed by microwave assisted dissolution with concentrated HNO3, aqua regia or 18.2 MΩ. An extended amount of metals were quantified for these samples (Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Li, Mn, Na, Ni, Pb, V, Zn) and most (not Ca, Li, K or Na) were compared with an ICP-MS instrument equipped with a collision cell used for the elements As, Fe and V. A final experiment was made on an L/S 10 of the samples to attempt to separate the metals from the salt with ion exchange, something that would make it possible to recycle this otherwise unused waste.

    The detection limits were all in the low μg L-1 except for Cd, Mn and Zn, which were between 2-4 μg L-1. The MP-AES was found to be able to handle matrices up to 5 g L-1 NaCl without a significant loss of response and provided near identical results to the ICP-MS for the elements that could be compared, this did not included the elements not quantified with the ICP-MS or V which was the only element under the limit of detection for the MP-AES. The experiment where an attempt was made to separate the metals from the salt was proven successful after treatment of bark compost and another type of waste ash as cation exchangers.

  • 178.
    Berg, Niklas
    et al.
    Örebro University, School of Science and Technology.
    Persson, Isac
    Örebro University, School of Science and Technology.
    Jämförelse mellan två metoder för mätning av kartongförpackningars greppstyvhet2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This Bachelor’s thesis is a collaborated work done between the paper manufacturer BillerudKorsnäs and Örebro University, within the research project "A New Model for Deformation of Carton Board Packages by Manual Handling". The aim of this work is to test and evaluate two methods regarding their ability to determine grip stiffness of cartonboard packages. This was achieved by analyzing how well each method was able to distinguish between various cartonboard qualities.

    The two methods that were compared were: box compression tests performed by a Lloyd Instrument LR5K tensile testing unit, and BioTac which is a finger-like tactile sensory device made by Syntouch LLC.

    About 120 box compression tests, with varying sphere sizes, were performed on cartonboard packages supplied by BillerudKorsnäs. Statistical methods were then applied to the data from these tests in order to see whether this method was able to distinguish between the different cartonboard materials.

    A member of the research project had previously performed experiments using the BioTac on the same types of packages. Data from those experiments underwent the same statistical tests. The results from the two methods could thus be compared.

    Albeit being able to distinguish maximum stiffnesses between the cartonboard materials for arbitrary forces, the box compression method failed at this endeavor for fixed low forces. The BioTac, however, showed better results in that regard.

  • 179.
    Bergendahl, Fredrik
    Örebro University, School of Science and Technology.
    RENODLA FLÖDET FÖR POWERTRONIC TRANSMISSIONENS ARTIKLAR2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Powertronic department at Volvo Powertrain, Köping manufactures and assembles automatic transmission called Powertronic and is primarily used in construction equipment. The manufacturing of parts for the gearbox has been the same in terms of layout and article flow point since the start of the department. The demand on the gearbox becomes more and more important due to price and quality, this results in the desire to be able to control and manage the time of how long the details are in manufacturing before assembly. It is difficult to achieve this because spare parts and prototypes are produced in the same machines and the workflow contains sections that are slow and difficult to assume the amount of time.

     

    The idea behind this study is to verify which of all the details that belong to the Powertronic gearbox and make a new flow of articles. The goal is to make it easier to manage and control the manufacturing time of articles and get exact value of this, resulting in reduced inventory and more profit. To achieve the desired results, analysis of flow and calculations of the differences between for and after a new flow and layout was implemented.

     

    The results show that improvements can be done for instance the production time of an article can be reduced by days. To get a new flow of articles requires some initial investments, most can be done with existing equipment.

     

    The recommendation is to place the new multi-tasking machine by following the proposal in this study and secondly to obtain a balancing equipment. 

  • 180.
    Berggården, Lizette
    Örebro University, School of Science and Technology.
    Flexibilitet i bostäder2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The development of Swedish society today is happening fast. With this comes that the surrounding enviroment of residental area is facing constant changes. The recidences change with the same speed as the social development. As a result floorplans of recidences have to be easy to change. To achieve easy transformable floorplans planners should pay attention to the possibility of transforming during the design stage.

    In this work flexible floorplans of residences have been studied. Flexible floorplans mean that changes can be made easily to the floorplan and at a low cost. The focus of this work have been to look at residential floorplans from two different periods. The first period is the time of the "million programme" (residential building programme during year 1965-1975 in Sweden) and the second period is the present time (year 2005-2015). The work describes why flexible floorplans are needed, which opportunities the flexibility gives, if flexibility is time-related or unchanged over time and if an open floorplan or closed floorplan affects the flexibility.

    Legislation regarding residential design has been studied to understand which rules have controlled the floorplannings during the different times. One essential difference between legislation and rules from the time periods is that in the first period, the law set the standard requirements and nowadays it sets functional requirements. The human way of life in the housing has been studied from the 1960´s until today to understand the requirements of housing development.

    The work is based on a qualitative method where facts mainly have been collected from published books that have been read critically. An analysis of floorplans from the "millione programme" and the present has been performed. The method has been successful due to having clear criteria set before the analysis to indicate if the floorplan had good flexibility or not.

    The analysis of the floorplans was made for each time period to examine if flexibility is time-related or unchanged over time. In the analysis open and closed floorplans were compared to see if the type of plan affects the flexibility. Closed floorplans represent the "million programme" period and open floorplans represent the present.

  • 181.
    Berglund, Erik
    et al.
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Charusta, Krzysztof
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Mapping between different kinematic structures without absolute positioning during operation2012In: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 48, no 18, 1110-1112 p.Article in journal (Refereed)
    Abstract [en]

    When creating datasets for modelling of human skills based on training examples from human motion, one can encounter the problem that the kinematics of the robot does not match the human kinematics. Presented is a simple method of bypassing the explicit modelling of the human kinematics based on a variant of the self-organising map (SOM) algorithm. While the literature contains instances of SOM-type algorithms used for dimension reduction, this reported work deals with the inverse problem: dimension increase, as we are going from 4 to 5 degrees of freedom.

  • 182. Berglund, S. Linnea
    et al.
    Agren, Goran I.
    Ekblad, Alf
    Örebro University, School of Science and Technology.
    Carbon and nitrogen transfer in leaf litter mixtures2013In: Soil Biology and Biochemistry, ISSN 0038-0717, E-ISSN 1879-3428, Vol. 57, 341-348 p.Article in journal (Refereed)
    Abstract [en]

    The decomposition rate of litter mixtures can differ from that expected on the basis of the decomposition rate of the individual components. This difference may be linked to nitrogen (N) transfer from high-N to low-N components. Transfer of N is probably also associated with transfer of C, but the extent and direction of this C transfer are unknown. This study examined transfer and loss in laboratory microcosms of C and N from two mixed litter species (Scots pine, Pinus sylvestris L and maize, Zea mays L), which have natural isotopic differences in C-13. Half the material was N-15-labelled and the plants were fertilised or unfertilised. Substantial bidirectional transfer of C and N occurred between the litters, with net transfer of C from pine to maize litter and net transfer of N from high-N to low-N litter. Mixtures of fertilised and unfertilised plant litter showed higher than expected C losses and net transfer of N. Mixtures with litters from the same fertilisation treatment had small or insignificant net transfer of N and their C losses did not differ from values estimated using the decomposition rates of the pure litters.

  • 183.
    Bergman, Malin
    Örebro University, School of Science and Technology.
    Determination of Polyoxymethylene (POM): Water Partition Coefficients for Alkylated Polycyclic Aromatic Hydrocarbons by Use of GC/MS2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Methods to measure the concentration of freely dissolved PAHs in pore water have been developed and are based on the usage of passive samplers, in this case polyoxymethylene (POM). Spiked samples (containing PAHs with 4-5 rings, methylated PAHs with 2-5 rings and dibenzothiophenes in three different concentrations) were placed on an end-over-end shaker for 28 days, to obtain equilibrium between the amount of PAHs accumulated on the POM strips and the amount of PAHs freely dissolved in the water. Four samples (medium concentration) were removed from the shaker after 7 and 14 days, respectively, and after 28 days were 12 samples (low, medium and high concentrations) removed. The variance of the average log(KPOM) values obtained from medium concentration were statistically tested, and showed that the coefficients for all compounds did not differ significantly over time. The coefficient difference between the three concentrations for the methylated PAHs were greater amongst the more hydrophobic compounds; 7,12-Dimethylbenz(a)anthracene had log(KPOM) of 5.64, 2.77 and 3.71 (low, medium, high). The hydrophilic compounds had coefficients that were more similar in the three concentrations; 1,6-Dimethylnaphthalene had log(KPOM) of 3.80, 2.62, and 3.39 (low, medium, high). Previous studies have determined log(KPOM) for several PAHs, and merged log(KPOM) for alkylated isomeric PAHs. The coefficients from the lowest concentration of serval methylated PAHs and Benzo(e)pyrene were similar to log(KPOM) values obtained for those compounds in an earlier study. The accuracy of risk assessments of PAH contaminated areas will increase when analysing individual methylated PAHs and using individual KPOM values for methylated PAHs, as in this study, instead of merged coefficients.

  • 184.
    Bergman-Ärlebäck, Jonas
    et al.
    Linköping University, Linköping, Sweden.
    Blomberg, Per
    Linnaeus University, Växjö, Sweden.
    Nilsson, Per
    Örebro University, School of Science and Technology. Linnaeus University, Växjö, Sweden.
    An instructional design perspective on data-modelling for learning statistics and modelling2015In: Development of mathematics teaching: Design, Scale, Effects: Proceedings of MADIF 9, The Ninth mathematics Education Research Seminar, 2015, 37-46 p.Conference paper (Refereed)
    Abstract [en]

    This theoretical and methodological paper discusses the emerging theoretical framing and methodological considerations in our efforts to develop a theoretical approach supporting instructional design for teaching and learning statistics and mathematical modelling. From an instructional design point of view aligned with the goals in governing curricula documents and real classroom constraints, we argue for the integration of the models and modelling perspective on teaching and learning mathematics with a data-modelling approach to facilitate students’ learning statistics and mathematical modelling. An application of the framework is given and future research discussed.

  • 185.
    Bergstedt, Martin
    et al.
    Örebro University, School of Science and Technology.
    Gillström, Tobias
    Örebro University, School of Science and Technology.
    Observator för frontlinjen på surfplatta2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been carried out at Saab Dynamics. The project's purpose was to develop an application, TBFO, for reporting information containing how the missile GLSDB would strike a target. TBFO is intended to be used in the proximity of the target and information is sent to the planning system GLSDB MPS.

    The application was built around the 3D engine from Vricon and is developed to fit for use of touch devices. The main part of the work concerns the development of user interface for touch input and the system’s application protocol.

    This report describes the processes of developing the system, including what tools and methods that have been used during development. The report also provides an in-depth look at processes used when developing applications for touch devices.

    The conclusion from the results of this project is that the idea of the described system is useful for the process of planning an assault with GLSDB MPS.

  • 186.
    Bergsten, Pontus
    et al.
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Siemens AG Corporate Technology, Otto-Hahn-Ring, Munich, German.
    Driankov, Dimiter
    Örebro University, School of Science and Technology.
    Observers for Takagi-Sugeno fuzzy systems2002In: IEEE transactions on systems, man and cybernetics. Part B. Cybernetics, ISSN 1083-4419, E-ISSN 1941-0492, ISSN 1083-4419/02, Vol. 32, no 1, 114-121 p.Article in journal (Refereed)
    Abstract [en]

    We focus on the analysis and design of two different sliding mode observers for dynamic Takagi-Sugeno (TS) fuzzy systems. A nonlinear system of this class is composed of multiple affine local linear models that are smoothly interpolated by weighting functions resulting from a fuzzy partitioning of the state space of a given nonlinear system subject to observation. The Takagi-Sugeno fuzzy system is then an accurate approximation of the original nonlinear system. Our approach to the analysis and design of observers for Takagi-Sugeno fuzzy systems is based on extending sliding mode observer schemes to the case of interpolated multiple local affine linear models. Thus, our main contribution is nonlinear observer analysis and design methods that can effectively deal with model/plant mismatches. Furthermore, we consider the difficult case when the weighting functions in the Takagi-Sugeno fuzzy system depend on the estimated state

  • 187.
    Bergstrand, Simon
    Örebro University, School of Science and Technology.
    Programmering av styrutrustning för vridbord vid radarmätplats2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When calibrating a radars antenna the radar is placed on a turntable that points it to a measuring point on a tower. The main task for the thesis was to write a program in National Instruments programming environment LabVIEW that can turn the turntable with an accuracy of 0.1 milliradians. The program shall be able to be used as a DLL (Dynamic-link library) in LabWindows/CVI where a number of different functions shall be able to control the turntable. Because all of the hardware is from National Instruments the software development became easy. The challenge was instead to measure the lengths and angles of the turntable and at testing be so precise that is necessary. All requirements were met but the lack of accuracy when testing makes the results a bit uncertain.Another part of the thesis was to write documents that specify requirements, interfaces and also describes how the software will be designed, tested and calibrated. For these documents the MIL-STD-498 was used that used to be an American military standard.

  • 188.
    Bergström, Emma
    et al.
    Örebro University, School of Science and Technology.
    Hansson, Sara
    INVERKAN VID VAL AV DRAGSKIVETYP & DRAGSKIVEVINKEL PÅ YT- OCH MATERIALEGENSKAPER AV ETT USKILJNINGSHÄRDBART ROSTFRITT STÅL2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been designed to get a better understanding of the material and its properties in wire drawing. There have been six different experiments which were conducted with two different drawing angles of three different kinds of drawing dies; regular drawing die, smaller nib and bigger nib. The experiments have been through the beginning of the production where samples have been taken out and then be analyzed in the lab. Results from tensile tests, hardness profile, martensite- and lubrication quantity measurements has been studied and led to the conclusions.

    The conclusion shows that the surface of the wire drawn with the drawing angle 12° had fewer defects than the wire drawn with 18°. Defects that were found on the wire drawn with the bigger nib 18° consisted largely of transverse cracks. Generally the results were similar in all tests for both 12° and 18°, however, the results was diverge on several tests for the smaller

    nib 12° after the drawing die.

  • 189.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    A geometric evolution problem2002In: Quarterly of Applied Mathematics, ISSN 0033-569X, E-ISSN 1552-4485, Vol. 60, no 1, 37-73 p.Article in journal (Refereed)
    Abstract [en]

    A traditional approach to compression moulding of polymers involves the study of a generalized Hele-Shaw flow of a power-law fluid, and leads to the p-Poisson equation for the instantaneous pressure in the fluid. By studying the convex dual of an equivalent extremal problem, one may let the power-law index of the fluid tend to zero. The solution of the resulting extremal problem, referred to as the asymptotically dual problem, is known to have the property that the flow is always directed towards the closest point on the boundary. In this paper we use this property to introduce the concept of boundary velocity in the case of piecewise C2 domains with only convex corners, and we also give an explicit solution to the asymptotically dual problem in this case. This involves the study of certain topological properties of the ridge of planar domains.With use of the boundary velocity, we define a geometric evolution problem and the concept of classical solutions of it. We prove a uniqueness theorem and use a comparison principle to study the persistence of corners. We actually estimate "waiting times" for corners, in terms of geometric quantities of the initial domain.

  • 190.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    A geometric evolution problem arising in an asymptotic approach to compression moulding1998Licentiate thesis, monograph (Other academic)
  • 191.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    On a generality framework for proving tasks2015In: Proceedings of the Ninth Congress of the European Society for Research in Mathematics Education / [ed] Konrad Krainer; Nada Vondrova, 2015, 86-92 p.Conference paper (Refereed)
    Abstract [en]

    In this paper I present an analytic framework for generality in textbook proving tasks that involve functions. The framework is discussed in relation to results obtained when analysing tasks in integral calculus. The results show that the frameworks’ categories are easily distinguishable if the functions are explicitly described. The results are also promising regarding the possibility to clarify differences between textbooks. The analysed sections exemplify that there is not necessarily a correlation between the number of general proving tasks and the opportunities for students to engage in reasoning about arbitrary functions. Limitations and possible refinements of the framework are also discussed.

  • 192.
    Bergwall, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Hemmi, Kirsti
    Åbo Akademi University, Åbo, Finland; Uppsala University, Uppsala, Sweden.
    The State of Proof in Finnish and Swedish Mathematics Textbooks: Capturing Differences in Approaches to Upper-Secondary Integral Calculus2017In: Mathematical Thinking and Learning, ISSN 1098-6065, E-ISSN 1532-7833, Vol. 19, no 1, 1-18 p.Article in journal (Refereed)
    Abstract [en]

    Students’ difficulties with proof, scholars’ calls for proof to be a consistent part of K-12 mathematics, and the extensive use of textbooks in mathematics classrooms motivate investigations on how proof-related items are addressed in mathematics textbooks. We contribute to textbook research by focusing on opportunities to learn proof-related reasoning in integral calculus, a key subject in transitioning from secondary to tertiary education. We analyze expository sections and nearly 2000 students’ exercises in the four most frequently used Finnish and Swedish textbook series. Results indicate that Finnish textbooks offer more opportunities for learning proof than do Swedish textbooks. Proofs are also more visible in Finnish text-books than in Swedish materials, but the tasks in the latter reflect a higher variation in nature of proof-related reasoning. Our results are compared with methodologically similar U.S. studies. Consequences for learning and transition to university mathematics, as well as directions for future research, are discussed.

  • 193.
    Bergwall, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Knutsson, Malin
    Örebro University, School of Science and Technology.
    Students’ views on mathematical challenges in working as a teacher2014Conference paper (Refereed)
    Abstract [en]

    Many frameworks for teacher knowledge describe the work of a mathematics teacher as highly complex and therefore requires specialized competences (e.g. Rowland & Ruthven, 2011). At the same time, countries around the world have difficulties in recruiting highly qualified students to teacher education. Furthermore, teacher educators often express that prospective teachers question the amount and level of mathematics that they have to learn. Research on views about teaching often focuses on teachers’ views (Philipp, 2007). Less is known about students’ views about working as a teacher and how those might influence their choice of a profession. The focus of this study is on the views that students have on mathematical challenges associated with the work of a mathematics teacher, when compared to other occupations.

  • 194.
    Berna, Amalia
    et al.
    CSIRO Ecosystem Sciences and CSIRO Food Futures Flagship, ACT, Australia.
    Vergara, Alexander
    University of California San Diego, USA.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Huerta, Ramon
    University of California San Diego, USA.
    Afonja, Ayo
    Department of Chemistry, University College London, London, UK.
    Parkin, Ivan
    Binions, Russell
    Trowell, Stephen
    Evaluating zeolite-modified sensors: towards a faster set of chemical sensors2011In: Olfaction and electronic nose: proceedings of the 14th International Symposium on Olfaction and Electronic Nose (ISOEN 2011), May 2-5, 2011, New York City, USA, 2011, 50-52 p.Conference paper (Refereed)
    Abstract [en]

    The response of zeolite-modified sensors, prepared by screen printing layers of chromium titanium oxide (CTO), were compared to unmodified tin oxide sensors using amplitude and transient responses. For transient responses we used a family of features, derived from the exponential moving average (EMA), to characterize chemo-resistive responses. All sensors were tested simultaneously against 20 individual volatile compounds from four chemical groups. The responses of the two types of sensors showed some independence. The zeolite modified CTO sensors discriminated compounds better using either amplitude response or EMA features and CTO-modified sensors also responded three times faster.

  • 195.
    Bernau, Maja
    et al.
    Örebro University, School of Science and Technology.
    Olsson, Tobias
    Örebro University, School of Science and Technology.
    Kundtjänster för mobilapplikationer: Utveckling av rapportgenerator, symbolgenerator,RevitArchitecture–add-in och metadatahantering2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this project was to streamline and automate a business system. This was achieved through the implementation of four subtasks. This report describes what parts of the system that needed to be updated and why. It also describes how the development was carried out and what results the project ultimately led to.

     

    The project's tasks were to: Create a report generator designed to generate Excel documents.

    Develop a symbol generator where a user, through a web-based interface, could generate

    symbols. The symbols could then be used in the company's mobile application. Create an

    interface for a web service, and to develop an add-in for the modeling software Revit

    Architecture 2014.

  • 196.
    Bertilsson, Anders
    Örebro University, School of Science and Technology.
    Alternative welding methods for nitrogen alloyed steel2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project explores the feasibility of the solid-state welding method direct-drive friction welding to be used as a joining method for the nitrogen alloyed steel Uddeholm Vanax SuperClean, produced via processes based on powder metallurgy. Vanax SuperClean cannot be welded using fusion welding methods where the base material melts, due to nitrogen escaping the material, resulting in inferior quality welds. The cost of the material motivates the use of Vanax SuperClean for critical parts in applications, combined with a less costly material for the remaining parts, causing alternative joining methods to be examined.

    Vanax SuperClean is friction welded to itself and to Uddeholm steel types Stavax ESR and UHB 11. Samples are prepared for a number of examinations. Microstructures of the samples are examined using microscopy, microhardness testing is carried out per the Vickers principle, retained austenite is measured using X-ray diffraction and tensile testing of the welded samples is performed. Defect-free welds are produced in all examined samples, showing that the method is suitable for Vanax SuperClean and that no preheating or slow cooling of workpieces are necessary.

    The possibility of using friction stir welding as a joining method for Vanax SuperClean is discussed.

  • 197.
    Bertilsson, Jimmy
    et al.
    Örebro University, School of Science and Technology.
    Andersson, Joakim
    Örebro University, School of Science and Technology.
    Ställtidsoptimering2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Emhart Glass Ltd is a world leader in glass bottle manufacturing. They designautomated machines that shape glass bottles. In Sweden there are two factories,one in Örebro and one in Sundsvall. In Örebro they manufacture primarily spareparts and new parts for the machines while they in Sundsvall assemble themachines. There are a total of 15 factories and offices around the world with theheadquarter located in Swiss Cham.Since Emhart Glass Örebro has long setup times on some of their machines. Thisis why we want to identify the current setup process and how the setup processdiffers between operators. We will also look at whether there are anyopportunities for improvement to be made and if they have a standardized way towork. A document that describes how to setup work should be done will also bedeveloped.An excellent tool to shorten the setup time in a production is the SMED method.The philosophy behind SMED is that you should analyze and separate the innerand outer activities. Inner and outer activities mean those activities which canonly be performed when the machine is turned off, respectively those activitiesthat can be performed when the machine is in operation.In order to standardize the adjustment process so that all operators are working ina similar way it's required that you make a documentation about how the workshould be done. Therefore, checklists been developed to the operator. "Checklista- Omställning.xls" is a checklist with the purpose to be able to check which partsof the preparations they have made before the next setup work. It has beendesigned to be easy to keep track of what parts you have done if you had to workwith the machine between the trial or if you quit your shift and leaving parts of thework to the next operator.If all of these improvements are implemented, we expect a set-up time reductionof 20.5% which corresponds to about 35min per set-up. By ignoring the runningtime and only check on the setup times, one can see an improvement of 36.4%.

  • 198.
    Besold, Tarek R.
    et al.
    Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
    Kuehnberger, Kai-Uwe
    Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
    Garcez, Artur d'Avila
    City University London, London, UK.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Fischer, Martin H.
    University of Potsdam, Potsdam, Germany.
    Bundy, Alan
    University of Edinburgh, Edinburgh, Scotland.
    Anchoring Knowledge in Interaction: Towards a Harmonic Subsymbolic/Symbolic Framework and Architecture of Computational Cognition2015In: Artificial General Intelligence (AGI 2015), Springer, 2015, 35-45 p.Conference paper (Refereed)
    Abstract [en]

    We outline a proposal for a research program leading to a new paradigm, architectural framework, and prototypical implementation, for the cognitively inspired anchoring of an agent's learning, knowledge formation, and higher reasoning abilities in real-world interactions: Learning through interaction in real-time in a real environment triggers the incremental accumulation and repair of knowledge that leads to the formation of theories at a higher level of abstraction. The transformations at this higher level filter down and inform the learning process as part of a permanent cycle of learning through experience, higher-order deliberation, theory formation and revision.

    The envisioned framework will provide a precise computational theory, algorithmic descriptions, and an implementation in cyber-physical systems, addressing the lifting of action patterns from the subsymbolic to the symbolic knowledge level, effective methods for theory formation, adaptation, and evolution, the anchoring of knowledge-level objects, realworld interactions and manipulations, and the realization and evaluation of such a system in different scenarios. The expected results can provide new foundations for future agent architectures, multi-agent systems, robotics, and cognitive systems, and can facilitate a deeper understanding of the development and interaction in human-technological settings.

  • 199. Bidot, Julien
    et al.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lagriffoul, Fabien
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Geometric backtracking for combined task and motion planning in robotic systems2017In: Artificial Intelligence, ISSN 0004-3702, E-ISSN 1872-7921, Vol. 247, 229-265 p.Article in journal (Refereed)
    Abstract [en]

    Planners for real robotic systems should not only reason about abstract actions, but also about aspects related to physical execution such as kinematics and geometry. We present an approach to hybrid task and motion planning, in which state-based forward-chaining task planning is tightly coupled with motion planning and other forms of geometric reasoning. Our approach is centered around the problem of geometric backtracking that arises in hybrid task and motion planning: in order to satisfy the geometric preconditions of the current action, a planner may need to reconsider geometric choices, such as grasps and poses, that were made for previous actions. Geometric backtracking is a necessary condition for completeness, but it may lead to a dramatic computational explosion due to the large size of the space of geometric states. We explore two avenues to deal with this issue: the use of heuristics based on different geometric conditions to guide the search, and the use of geometric constraints to prune the search space. We empirically evaluate these different approaches, and demonstrate that they improve the performance of hybrid task and motion planning. We demonstrate our hybrid planning approach in two domains: a real, humanoid robotic platform, the DLR Justin robot, performing object manipulation tasks; and a simulated autonomous forklift operating in a warehouse.

  • 200.
    Bidot, Julien
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lagriffoul, Fabien
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Geometric backtracking for combined task and path planning in robotic systemsManuscript (preprint) (Other academic)
    Abstract [en]

    Planners for real, possibly complex, robotic systems should not only reason about abstract actions, but also about aspects related to physical execution such as kinematics and geometry. We present an approach in which state-based forward-chaining task planning is tightly coupled with sampling-based motion planning and other forms of geometric reasoning. We focus on the problem of geometric backtracking which arises when a planner needs to reconsider geometric choices, like grasps and poses, that were made for previous actions, in order to satisfy geometric preconditions of the current action. Geometric backtracking is a necessary condition for completeness, but it may lead to a dramatic computational explosion due to the systematic exploration of the space of geometric states. In order to deal with that, we introduce heuristics based on the collisions between the robot and movable objects detected during geometric backtracking and on kinematic relations between actions. We also present a complementary approach based on propagating explicit constraints which are automatically generated from the symbolic actions to be evaluated and from the kinematic model of the robot. We empirically evaluate these dierent approaches. We demonstrate our planner on a real advanced robot, the DLR Justin robot, and on a simulated autonomous forklift. 

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