miun.sePublikasjoner
Endre søk
Begrens søket
12 1 - 50 of 61
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Roller ski rolling resistance and its effects on elite athletes’ performance2008Inngår i: ENGINEERING OF SPORT 7, VOL 2, 2008, Vol. 11, nr 3, s. 393-400Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical fitness in a laboratory environment whilst performing classical and freestyle (skating) techniques on roller skis. For elite athletes the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance in order to allow the correct comparison between the results of different test occasions. In this study the roller skis’ rolling resistance has been measured using equipment on the ski-treadmill. The study investigates the influence of significant changes in rolling resistance on physiological variables. The results show that during submaximal exercise, heart rate, blood lactate, power and oxygen uptake are significantly changed by different rolling resistances, while there are no significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests show that time to exhaustion is significantly changed by different rolling resistances and this occurred without significant changes in maximal oxygen uptake and heart rate, and the influence on maximal power and ratings of perceived exertion were insignificant or small.

  • 2.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Roller ski rolling resistance and its effects on elite athletes’ performance2009Inngår i: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 11, nr 3, s. 143-157Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical fitness in a laboratory environment whilst performing classical and freestyle (skating) techniques on roller skis. For elite athletes, the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance in order to allow the correct comparison between the results of different test occasions. In this study, the roller skis’ rolling resistance was measured on the ski-treadmill’s surface using a roller ski rolling resistance measurement system specially produced for this purpose. The study investigated the influence of significant changes in rolling resistance on physiological variables. The results showed that during submaximal exercise, power, oxygen uptake, heart rate and blood lactate were significantly changed by different rolling resistances, while there were no significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed by different rolling resistances and this occurred without significant changes in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion were insignificant or small.

     

  • 3.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Rolling resistance for treadmill roller skiing2008Inngår i: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 11, nr 1, s. 23-29Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Modern treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical performance under laboratory conditions using classical and freestyle techniques on roller skis. The differences in performance between tests are quite small for elite athletes, and it is therefore of great importance to control the rolling resistance of the roller skis. Otherwise different physiological tests cannot be accurately compared.

    This study shows that during a warm-up period of  30 minutes the coefficient of rolling resistance (µR) decreases to about 60-65% and 70-75% of its initial value for freestyle and classical roller skis respectively.

    Simultaneous measurements of temperature and µR shows that stabilized rolling resistance corresponds to a certain running temperature for a given normal force on the roller ski.

    Tests were also performed on the influence on µR of normal force, velocity and inclination. Normal forces produced significant influence on µR , while different velocities and inclinations of the treadmill only resulted in small changes in µR.

  • 4.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Laaksonen, Marko
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Work economy of amateur and elite cross-country skiers during treadmill roller skiing2009Inngår i: 4th Asia Pacific Congress on Sports Technology, APCST2009, 2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This study focused on the work economy of cross-country skiers during treadmill roller skiing in the perspectives; skill, age and gender. The study was investigating the external power output from elevating the transported mass against gravity and overcoming the roller skis rolling resistance, and the internal power from measured oxygen uptake and energy consumption. The roller skis rolling resistance was measured with a fixture on the ski-treadmill and the results showed a significant correlation between normal force and rolling resistance. The results also showed that it was only the amateur skiers who significantly differed in work economy among the five studied groups.

  • 5.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Laaksonen, Marko S.
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för hälsovetenskap.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    The influence of grip on oxygen consumption and leg forces when using classical style roller skis2014Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 24, nr 2, s. 301-310Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of this study was to investigate the influence of classical style roller skis' grip (static friction coefficients, μ S) on cross-country skiers' oxygen consumption and leg forces during treadmill roller skiing, when using the diagonal stride and kick double poling techniques. The study used ratcheted wheel roller skis from the open market and a uniquely designed roller ski with an adjustable camber and grip function. The results showed significantly (P≤0.05) higher oxygen consumption (∼14%), heart rate (∼7%), and lower propulsive forces from the legs during submaximal exercise and a shorter time to exhaustion (∼30%) in incremental maximal tests when using roller skis with a μ S similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a similar, higher μ S. Thus, we concluded that oxygen consumption (skiing economy), propulsive leg forces, and performance time are highly changed for the worse when using roller skis with a lower μ S, such as for on-snow skiing with grip-waxed cross-country skis, in comparison to ratcheted wheel roller skis with several times higher μ S.

  • 6.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    A portable roller ski rolling resistance measurement system2013Inngår i: The Impact of Technology on Sport V: Procedia Engineering / [ed] Subic A, Fuss FK, Clifton P, Chan KM., Elsevier, 2013, s. 79-83Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Roller skis are used by cross-country skiers, biathletes and ski-orienteers for their snow-free training and in roller ski competitions. Additionally, much of the current sports research into the physiology and biomechanics of crosscountry skiing is conducted indoors on treadmills using roller skis. For elite athletes, the differences in performance are quite small, thus emphasising the importance of knowing the roller skis' rolling resistance coefficient, especially in connection to research and roller ski competitions. The purpose of this study was to develop a roller ski rolling resistance measurement system (P-RRMS) that is portable and therefore useful in different contexts and locations. The P-RRMS was designed as a small treadmill, equipped with roller ski stabilizing lateral supports and a screwed bar for applying different vertical loads on the roller ski. The design uses only one force sensor, with possible measurements of three directions of force and torque around three axes. The weight of the P-RRMS is 100 kg and it is equipped with wheels to facilitate transportation.

  • 7.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    An experimental study to compare the grip of classical style roller skis with on-snow skiing2013Inngår i: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 16, nr 2, s. 115-122Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cross-country skiers use roller skis for their snow-free training with the aim of imitating skiing on snow. Also, exercise laboratories evaluate the biomechanics and physiology of cross-country skiing using roller skis on a treadmill. The roller skis on the market that are constructed for use in the classical style are equipped with a front and a back wheel, one of which has a ratchet to enable it to grip the surface when diagonal striding and kick double poling (static friction). The aim of this study was to investigate static friction coefficients (μS) of ratcheted wheel roller skis, and compare the results to the μS reported from skiing on snow with grip-waxed cross-country skis. Also, a new type of roller ski with a camber and adjustable grip function was evaluated. The results showed that ratcheted wheel roller skis, on a treadmill rubber mat and on dry and wet asphalt surfaces, reached μS values that were five to eight times greater than the values reported from on-snow skiing with grip-waxed cross-country skis. For the roller skis with a camber and adjustable grip function, the μs could be varied from no grip at all up to the level of the tested ratcheted wheel roller skis.

  • 8.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Classical style constructed roller skis and grip functionality2011Inngår i: Procedia Engineering: The Impact of Technology on Sports IV / [ed] Subic A., Fuss F.K., Alam F., Clifton P., Elsevier, 2011, s. 4-9Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Roller skis are used by cross-country skiers for snow-free training, with the aim of imitating skiing on snow. The roller skis on the market that are constructed for use in the classical style are equipped with a front and a back wheel, one of which has a ratchet to enable it to grip the surface when diagonal striding and kick double poling.

    A new type of roller ski was constructed with a function which makes it necessary to use the same kick technique as that used on snow, i.e. the ski has a camber that must be pushed down to obtain grip. Its stiffness can be adjusted based on factors that influence grip, i.e. the skier’s bodyweight and technical skiing skills.

    Thus, our aim was to make comparative measurements as regards grip between ratcheted roller skis and the roller ski with a camber and compare with previous published results for grip waxed skis during cross-country skiing on snow.  The measurements were carried out using specially developed equipment, with a bottom plate and an overlying rubber mat of the same type as used on many treadmills and a function for applying different loads and generating traction on the back of the roller ski.

  • 9.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Rolling resistance for treadmill roller skiing: Presented at International Congress on Science and Nordic Skiing 2006, June 18-20, 2006, Vuokatti, Finland2006Konferansepaper (Annet vitenskapelig)
  • 10.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Laaksonen, Marko S.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Skiing economy and efficiency in recreational and elite cross-country skiers2013Inngår i: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 27, nr 5, s. 1239-1252Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of this study was to investigate and compare skiing economy and gross efficiency in cross-country skiers of different performance levels, ages and genders; male recreational skiers and elite senior and junior cross-country skiers of both genders. The skiers performed tests involving roller skiing on a treadmill using the gear 3 and diagonal stride techniques. The elite crosscountry skiers were found to have better skiing economy and higher gross efficiency (5-18%) compared with the recreational skiers (p < 0.05) and the senior elite had better economy and higher efficiency (4-5%) than their junior counterparts (p < 0.05), whereas no differences could be found between the genders. Also, large ranges in economy and gross efficiency were found in all groups. It was concluded that, in addition to v̇O2peak, skiing economy and gross efficiency have a great influence on the differences in performance times between recreational and junior and senior elite cross-country skiers, as well as between individual skiers within the different categories. Thus, we recommend crosscountry skiers at all performance levels to test not only v̇O2peak, but also skiing economy and efficiency.

  • 11.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Rännar, Lars-Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    The multi functional roller ski2012Konferansepaper (Fagfellevurdert)
  • 12.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Rännar, Lars-Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    The multifunctional roller ski2013Inngår i: Science and Nordic Skiing II / [ed] Hakkarainen A, Linnamo V, Lindinger S, University of Salzburg, University of Jyväskylä , 2013, s. 253-261Kapittel i bok, del av antologi (Fagfellevurdert)
  • 13.
    Ainegren, Mats
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kvalitets- och maskinteknik.
    Tuplin, Simon
    Loughborough University, Loughborough, UK.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kvalitets- och maskinteknik.
    Render, Peter
    Loughborough University, Loughborough, UK.
    Design and development of a climatic wind tunnel for physiological sports experimentation2019Inngår i: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, ISSN 1754-3371, Vol. 233, nr 1, s. 86-100Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this project was to develop a wind tunnel that enables the study of human performance during various types ofsports and physical activities by examining the influence of aerodynamic drag, precipitation, frictional forces and gravitationalforces on uphill and downhill travel on a moving substrate. An overall design for a wind tunnel and working section containinga large treadmill was drafted, followed by computational fluid dynamics simulations of flow conditions to assess thedesign’s feasibility and select from different geometries prior to its construction. The flow conditions in the completed windtunnel were validated using different flows, speeds and treadmill inclinations. Pilot experiments were carried out using across-country skier to investigate the effect of aerodynamic drag on oxygen uptake during double poling and the maximalachieved speed when rolling on a declined treadmill. The purpose was to validate the usefulness of the tunnel. The resultsshowed that flow conditions are acceptable for experiments even in worst-case scenarios with maximal inclined and declinedtreadmill. Results also showed that aerodynamic drag has a significant impact on the skier’s energy expenditure.

  • 14.
    Bäckström, Mikael
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Danvind, Jonas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Koptioug, Andrei
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Sundström, David
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    A New Wind Tunnel Facility Dedicated to Sports Technology Research and Development2016Inngår i: Procedia Engineering, Elsevier, 2016, Vol. 147, s. 62-67Konferansepaper (Fagfellevurdert)
    Abstract [en]

    It is desirable to test sportswear and sports equipment at exactly the same conditions experienced during use. Although outdoor tests are in many cases the most adequate, they are at the same time quite complex, demand special measurement technology and wearable equipment. Results of such tests are often hard to interpret due to large variations because of rapidly varying ambient conditions and individual specifics of human objects, among other factors, which are hard or impossible to control. One common alternative is provided through indoor tests made in a stable, controlled environment. Controlling such parameters as temperature, wind speed and direction, air humidity with indoor facilities intended to replicate ambient conditions, and designed to house large objects, is a complex undertaking. Furthermore, replicating seasonal conditions complicates matters even more. A significant amount of research and development related to the operation of sports and other related equipment at high speeds and windy conditions has been carried out in wind tunnels with different degrees of climatic realism. However, the majority of such facilities are designed and constructed for the automotive industry, the aerospace industry and for marine research. A new wind tunnel facility, opened in March 2015 at the Sports Tech Research Centre at Mid Sweden University, is currently among the very few facilities in the world designed under the direct control of sports technology specialists and dedicated primarily to research and development within sports, outdoor clothing and footwear as well as equipment development and testing. The main goal when constructing this dedicated facility has been to successfully replicate ambient conditions for training and equipment testing in environments with controlled wind speed, temperature (+4 to +35°C) and precipitation (from fine mist to heavy downfall). The wind tunnel facility houses the largest moving belt in Sweden (5 m long and 2.7 m wide) which can be adjusted for leveled, uphill and downhill motion. The moving belt is placed in a 10 m2 test section in which the wind speed can be adjusted to match belt speed or independently up to 55 km/h (without narrowing the test section). A fog and rain system, mounted in the test section, can generate rainy conditions varying from fine mist to heavy monsoon. It is also possible to open the facility in order to allow experiments to be performed in wide range of outdoor, ambient conditions. This paper presents the basic parameters of the new wind tunnel facility. As this facility is open for wider international cooperation, we also report the general directions of current research and the future work planned to be carried out at this facility.

  • 15.
    Bäckström, Mikael
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Koptyug, Andrey
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Rännar, Lars-Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Danvind, Jonas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Wiklund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Sports Technology Education at Mid Sweden University2013Inngår i: 6TH ASIA-PACIFIC CONGRESS ON SPORTS TECHNOLOGY (APCST), Elsevier, 2013, Vol. 60, s. 214-219Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In present paper we would like to share some experiences of building new education in Sports Technology at MidSweden University and the results of 10 years of successfully running it in Östersund. The Sports Technologyeducation at Mid Sweden University started at Campus Östersund in 2003 as a part of the curriculum of theEngineering Department. This specialization was initially at the three-year Bachelor level, and later it was extendedto an additional two-year Master level. Aiming at the quality of Sports Technology education, three keystones areunderlying its process, representing the solid knowledge base, capacity to be flexible in problem solving and the usean innovative approaches. The Department unites researches with a background in both natural sciences andengineering disciplines, having a wide experience of working with and within the industry, equally active in researchand teaching. The unique constellation of the profiles forming the Department include not only the SportsTech®group, being “the backbone”, but also the Ecology and Eco-technology, and Quality Technology groups bringing theexcellence and extra competence needed to assure the quality of the Sports Technology education. We were the firsthigher education institution in Sweden to give this kind of education program and now some other SwedishUniversities have followed us. Our success can be measured by a number of graduates taking good jobs in theindustry. We also enjoy a steady flow of new students coming from all parts of Sweden, and Sports Technologyeducation stays among the most desirable ones in the country.

  • 16.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Distributed optimization with a two-dimensional drying model of a board, built up by sapwood and heartwood2001Inngår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 55, nr 4, s. 426-432Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Optimization with distributed computing is performed on a two-dimensional orthotropic drying model which allows boards with arbitrary outtake of the log and sapwood/heartwood distribution in the cross section. Drying schedules with an optimized variation of temperature and humidity which yields minimized drying time are created at the same time as moisture, stress and deformation levels are considered. A numerical example with distributed computing of a board with a mixture of sapwood and heartwood is presented. Drying starts from the fibre saturation point.

  • 17.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Irreversibel termodynamik i trätorkningssammanhang1994Rapport (Annet vitenskapelig)
  • 18.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimization of the Wood Drying Process1997Licentiatavhandling, med artikler (Annet vitenskapelig)
  • 19.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimized Wood Manufactoring with Main Focus on Wood Drying2000Doktoravhandling, med artikler (Annet vitenskapelig)
  • 20.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Promote IT 2005: Proceedings of the fifth Conference for the Promotion of Research in IT at New Universities and University Colleges in Sweden - Borlänge, Sweden 11-13 May, 2005 / editied by Janis Bubenko jr2005Inngår i: Promote IT 2005: Proceedings of the fifth Conference for the Promotion of Research in IT at New Universities and University Colleges in Sweden - Borlänge, Sweden 11-13 May, 2005 / editied by Janis Bubenko jr, Lund: Studentlitteratur , 2005, , s. 460Konferansepaper (Fagfellevurdert)
  • 21.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Sundström, David
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Esping, Björn
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Koptioug, Andrey
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Bäckström, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Cross-Country Ski2015Inngår i: The Engineering Approach to Winter Sports / [ed] Braghin F., Cheli F., Maldifassi S., Melzi S. and Sabbioni E., Springer, 2015, s. 107-152Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    Cross-country skiing, biathlon and ski orienteering are competitive sports with practitioners who are mostly from countries in the northern hemisphere. The competition season is during the time when the ground is covered with snow, which roughly extends from mid-November to late March. During the rest time of the year, which is a long preparatory period of training for the skiers before the competition season, the skiers use roller skis for dryland training with the aim of imitating skiing on snow. Furthermore, over the last few decades, fairly specific indoor testing methods for cross-country skiers have become possible due to the development of treadmills that allow roller skiing using classical and freestyle techniques.

  • 22.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Arfvidsson, J
    Optimized wood drying1999Inngår i: Wood Drying research and technology for sustainable forestry beyond 2000 : , 1999, Stellenbosch, South Africa.: 6th International IUFRO Conference on Wood Drying, 25-28 January, 1999, Matieland, South Africa: Dept. of Wood Science, Faculty of Forestry , 1999, s. 310-Konferansepaper (Fagfellevurdert)
  • 23.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Arfvidsson, J
    Optimized wood drying2000Inngår i: Drying Technology, ISSN 0737-3937, Vol. 18, nr 8, s. 1779-1796Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nonlinear programming methods are used to create effective drying schedules for boards. A two-dimensional. orthotropic drying model is connected to an optimization routine that solves convex sub-problems. The iterative optimi7ation program calculates the drying schedule. i.e. the variation of temperature and humidity with time, that gives the shortest drying time for a board with prescribed upper and lower level of the moisture content. To demonstrate the capability of the technique. numerical results are presented.

  • 24.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Esping, Björn
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimization of the wood drying process1997Inngår i: Structural Optimization, ISSN 0934-4373, Vol. 14, nr 4, s. 232-241Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Modern optimization methods offer tools to create new, and to modify existing wood drying schedules. The total drying time can be minimized, at the sazne time as both the moisture content and the deformation after completed drying are within acceptable limits. The stress levels during drying are also considered.

  • 25.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Esping, Björn
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Dahlblom, O
    Ormarsson, S
    Söderström, O
    Optimization, a tool with which to create an effective drying schedule1998Inngår i: Holzforschung, ISSN 0018-3830, Vol. 52, nr 5, s. 530-540Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A method for defining effective schedules for kiln drying of wood is presented. The method is designed in such a way that it proposes an optimized variation of temperature and humidity which yields the minimum total drying time, with the condition that the moisture content and the deformation not exceed specified limits after the drying and that the stress not exceeds a specified level at any time during the drying process in order to avoid crack development. To demonstrate the capability of the optimization method numerical results are presented. It should be noted that ill this first approach, drying starts from moisture content corresponding to the fibre-saturation point, i.e. approximate to 30%).

  • 26.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Esping, Björn
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Dahlblom, Ola
    Optimization of the wood-drying process.1996Inngår i: Quality Wood Drying Through Process Modelling and Novel Technologies, Quebec Canada, Aug. 13-17, 1996: 5th International IUFRO Conference on Wood Drying, 25-28 January, 1999, Sainte-Foy, Québec: Forintek Canada Corp , 1996, s. 559-Konferansepaper (Fagfellevurdert)
  • 27.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    A combined laminate and honeycomb wood model for softwood used for numerical optimization of a violin top2002Inngår i: Forum Acusticum Sevilla 2002 : 3rd European congress on accoustics, XXXIII Spanish congress on accoustics, TECNIACUSTICA 2002, European and Japanese congress on acoustics, 3rd Iberian congress on acoustics. Sevilla, Spain 16-20 September 2002, Madrid Madrid: Soc. Espanola de Acústica , 2002Konferansepaper (Fagfellevurdert)
  • 28.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    A distributed computing system used for concurrent optimization methods on a violin top2003Inngår i: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 25, nr 5/6, s. 453-458Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Concurrent optimization is performed with two optimization methods on a violin top. The optimization methods used are SA (Simulated Annealing) and MMA (Method of Moving Asymptotes). All calculations in this study are made in a distributed environment for arbitrary processing. The distributed environment is constructed using extended File Servers running on remote computers and clients on a local computer, which can transfer, start, terminate, and finally remove arbitrary Java RMI Servers from the remote computers. The required processing is performed with the RMI Servers.

  • 29.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Determination of important wood properties for blanks for violin tops by the use of numerical optimization.2003Inngår i: Proceedings of the Stockholm Music Acoustics Conference, August 6-9, 2003 (SMAC 03), Stockholm, Sweden Edited by Roberto Bresin, Sth: KTH , 2003, s. 428-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In the strive of understanding how different parameters affects the vibration properties and the characteristics of the sound emanating from a violin, i.e. what makes a good violin good, numerical methods as FEM (finite element method) and BEM (boundary element method) are used. Numerical models of whole violins and/or part of it is created and studied. Crucial for the results from these studies is the correctness of the input data for the numerical analysis. One important group of input data is the wooden material parameters for the part of the violin subjected to analysis. In this study a new method for determining these important material parameters for blanks for violin tops is proposed. In the proposed method a FEM-code is linked together with a stochastic optimization algorithm in order to, in an automatic fashion, determine the material parameters. The method requires the geometrical dimensions, the density, and measured normal modes for the blank and it consider the fact that the Young’s modulus in the axial direction varies with respect to the radial direction.

  • 30.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Geometrical compensation for varying material properties in bows by the use of numerical optimization2007Inngår i: Acta Acoustica united with Acustica, ISSN 1610-1928, E-ISSN 1861-9959, Vol. 93, nr 1, s. 145-151Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wood for violin bows from the pernambuco tree shows large variations in density. For high quality bows, the higher densities are preferred. Since pernambuco is rare and expensive, it is of interest to investigate if it is possible to compensate for variations in density between blanks for bows; particularly in such a way that important qualities of high quality bows are maintained in bows made of wood with a lower density. In this study, numerical optimization is used to replicate some of the static and dynamic properties of a reference bow, using wood with 10% lower density. The structural calculations of the bow are made with a finite element program (ANSYS), which is coupled to an external optimization routine. The automatic optimization process is performed using the Method of Moving Asymptotes. Included are also some remarks on how homogenous scaling of the cross section of a bow of constant length affects some of the static and dynamic properties when used as compensation for density variations.

  • 31.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Numerical optimization of geometrical dimensions and determination of material parameters for violin tops2002Inngår i: Forum Acusticum Sevilla 2002 : 3rd European congress on accoustics, XXXIII Spanish congress on accoustics, TECNIACUSTICA 2002, European and Japanese congress on acoustics, 3rd Iberian congress on acoustics. Sevilla, Spain 16-20 September 2002, Madrid: Soc.Espanola de Acústica , 2002Konferansepaper (Fagfellevurdert)
  • 32.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Numerical optimization of violin bows with varying densities of the wood material2003Inngår i: Proceedings of the Stockholm Music Acoustics Conference, August 6-9, 2003 (SMAC 03), Stockholm, Sweden, Stockholm: KTH , 2003, s. 423-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The wood material for violin bows from the pernambuco tree (Caesalpina echinata) has large individual variations in the density. For high quality bows, the higher densities are preferred, but since pernambuco is rather rare and expensive, it is of interest to investigate if it is possible to compensate for density variations in the wood material, at the same time as important qualities of the bow are unchanged. In this study, numerical optimization is used to recover the static and dynamic properties of a reference bow, on a bow with 10% lower density. The structural calculations of the bows are made with a umerical model in the finite element program ANSYS, which in its is coupled to an external, gradient based optimiztion routine. The automatic optimization process is performed with a routine called the Method of Moving Asymptotes (MMA).

  • 33.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimization of a violin top with a combined laminate and honeycomb model of the wood material2003Inngår i: Holzforschung, ISSN 0018-3830, Vol. 57, nr 1, s. 101-105Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stochastic optimization with the simulated annealing method (SA) is performed on a violin top made of Norway spruce (Picea Abies). A numerical example is presented which shows that it is possible, through changes in thickness variables, to compensate for changes in vibration properties caused by a variation in the material parameters in the top. A material model is also presented for the blank which considers the influence of density variations in the annual rings, the cellular structure of wood and reinforcement from the wood rays.

  • 34.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimization of acoustic response with numerical and experimental comparison2001Inngår i: Proceedings of the Eighth International Congress on Sound and Vibration 2001 : 2-6 July 2001, the Hong Kong Polytechnic University, Hong Kong, China: ICSV8, Hong Kong 2001, Hong Kong: Hong Kong Polytechnic University , 2001, s. 2121-2128Konferansepaper (Fagfellevurdert)
  • 35.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimization of Drying Schedules Adapted for a Mixture of Bords with Distribution of Sapwood and Heartwood2002Inngår i: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 20, nr 2, s. 403-418Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A distributed optimization model for wood drying with several different boards simultaneously is presented. Optimization is performed with a gradient-based program. During optimization, convex subproblems are created and transformed to the dual problem and solved. Arbitrary outtakes and board dimensions are possible, as well as different material data and distribution of sapwood and heartwood. It is also possible to optimize drying schedules where drying of boards with variations in environmental conditions is simulated. A two-dimensional orthotropic drying model is used in the moisture transport and structural analysis, where the variation in radial and tangential directions are considered. The influence of temperature and moisture content on material data and mechanical properties is also taken into account. The drying schedules achieved are optimized to minimize drying time for a representative mixture of boards. A numerical example is presented where the drying schedule is optimized for two boards with different outtakes and distributions of sapwood and heartwood. Optimization is performed with two computers in a network. Drying starts from the fibre saturation point in these simulations.

  • 36.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimized wood drying of a mixture of representative boards2001Inngår i: Moisture control in environment-friendly housing and wood drying technology in new century : July 9-13, 2001 Tsukuba, Japan: 7th International IUFRO Wood Drying Conference proceedings, Ibaraki, Japan: Forestry and Forest Products Research Institute , 2001, s. 461-Konferansepaper (Fagfellevurdert)
  • 37.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Stochastic optimization of violin tops2001Inngår i: International symposium on musical acoustics 2001. - Perugia, Italia, 10-14 September 2001: ISMA 2001 ; (Perugia) : 2001, Venezia: Fondazione Giorgio Cini , 2001, s. 640-Konferansepaper (Fagfellevurdert)
  • 38.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Numeric Simulation of Cross Country Skiing2009Konferansepaper (Fagfellevurdert)
  • 39.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Ainegren, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Numerical Simulation of Cross Country Skiing2011Inngår i: Computer Methods in Biomechanics and Biomedical Engineering, ISSN 1025-5842, E-ISSN 1476-8259, ISSN 1025-5842, Vol. 14, nr 8, s. 741-746Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A program for numerical simulation of a whole ski race, from start to finish, is developed in MATLAB. The track ismodelled by a set of cubical splines in two dimensions and can be used to simulate a track in a closed loop or with the startand finish at different locations. The forces considered in the simulations are gravitational force, normal force between snowand skis, drag force from the wind, frictional force between snow and ski and driving force from the skier. The differentialequations of motion are solved from start to finish with the Runge–Kutta method. Different wind situations during the racecan be modelled, as well as different glide conditions on different parts of the track. It is also possible to vary the availablepower during the race. The simulation program’s output is the total time of the race, together with the forces and speedduring different parts of the race and intermediate times at selected points. Some preliminary simulations are also presented.

  • 40.
    Carlsson, Peter
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Esping, Björn
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Optimization of a racing ski: Brief notes1995Inngår i: Structural Optimization, ISSN 0934-4373, Vol. 10, nr 1, s. 61-63Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper shows how very tradition-bound construction can be improved through the use of modern technology. In this case, a cross-country ski, the construction can be traced back to a ski found in a swamp in Vasterbotten in northern Sweden, a ski approximately 5000 years old. (4 refs.)

  • 41.
    Dahlen, Leon
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Numerical optimization of a distributor valve2005Inngår i: WIT Transaction on the Built Environment, 2005, Vol. 80, s. 333-343Konferansepaper (Fagfellevurdert)
  • 42.
    Dahlen, Leon
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Kuzmin, Leonid
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Olsson, Nils
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Adventure technology and sport science - A research project at Mid Sweden University: 5th international engineering of sport. 13-16 september, UC Davis, USA.2004Konferansepaper (Annet vitenskapelig)
  • 43.
    Dahlén, Leon
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Numerical optimization of a distributor valve2003Inngår i: International Journal of Fluid Power, ISSN 1439-9776, Vol. 4, nr 3, s. 17-25Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper a non-linear optimization method is used to improve the design of a distributor valve. The distributor valve is an important component in a radial piston hydraulic motor, and optimization of the design to minimize power losses is an interesting way to increase efficiency. The main function of a distributor valve is to supply the pistons with a pressurized flow and to return oil during rotation. At the same time the distributor valve acts as an externally pressurized lubricated thrust bearing, in order to separate the rotating parts from the motor case. The bearing acts as a hydrostatic annular multi-recess plane thrust bearing, with different recess pressures. The separating force of the bearing is balanced hydrostatically by the pressure that is applied and springs. Losses will occur in the contact between the parts in the distributor valve, due to friction and leakage. This paper shows that modern optimization methods can be used as an effective tool to create new designs and to modify the existing design of the bearing surface geometry of the distributor. A finite element method has been used to simulate the contact, and the program is linked to an optimization routine to perform the optimization. The results of the optimized design show a significant decrease in power loss, compared to the existing design in the operating range. (23 refs.)

  • 44.
    Ek, Rebecca
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Rännar, Lars-Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Bäckström, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    The Effect of EBM Process Parameters upon Surface Roughness2016Inngår i: Rapid prototyping journal, ISSN 1355-2546, E-ISSN 1758-7670, Vol. 22, nr 3, s. 495-503Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose-The surface roughness of products manufactured using the additive manufacturing (AM) technology of electron beam melting (EBM) has a special characteristic. Different product applications can demand rougher or finer surface structure, so the purpose of this study is to investigate the process parameters of EBM to find out how they affect surface roughness. Design/methodology/approach-EBM uses metal powder to manufacture metal parts. A design of experiment plan was used to describe the effects of the process parameters on the average surface roughness of vertical surfaces. Findings-The most important electron beam setting for surface roughness, accorDing to this study, is a combination of speed and current in the contours. The second most important parameter is contour offset. The interaction between the number of contours and contour offset also appears to be important, as it shows a much higher probability of being active than any other interaction. The results show that the line offset is not important when using contours. Research limitations/implications-This study examined contour offset, number of contours, speed in combination with current and line offset, which are process parameters controlling the electron beam. Practical implications-The surface properties could have an impact on the product's performance. A reduction in surface processing will not only save time and money but also reduce the environmental impact. Originality/value-Surface properties are important for many products. New themes containing process parameters have to be developed when introducing new materials to EBM manufacturing. During this process, it is very important to understand how the electron beam affects the melt pool.

  • 45.
    Esping, Björn
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Johnsson, M
    Optimization of violin tops with focus on determining correct material properties2005Inngår i: World Congress on Structural and Multidisciplinary Optimization, 6th. Proceedings (CD-ROM): WCSMO6, May 30 - June 3, Rio de Janeiro, Brazil., 2005Konferansepaper (Fagfellevurdert)
  • 46.
    Koptyug, Andrey
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Bäckström, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Cross-country ski vibrations and possible mechanisms of their influence on the free gliding2012Inngår i: Procedia Engineering, ISSN 1877-7058, E-ISSN 1877-7058, Vol. 34, s. 473-478Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Present paper describes the results of experimental studies on the self-induced and forced vibrations of loaded cross country skis and presents the discussion on the possible mechanisms causing such vibrations and the ways they can influence the friction between the ski running surface and the snow. Studied vibrations of gliding skis are most probably caused by the frictional effects. Mechanisms involved are similar to the ones causing the brake disc squeal or the violin string excitation by the bow. Major factors responsible for the development of these vibrations such as micro roughness of the surfaces, nonlinearities in the material properties, thermo-elastic instabilities and instabilities due to decreasing friction with increasing sliding velocity are also common for the case of gliding skis. The results of this study indicate that the ski vibration pattern both in amplitude and in frequency could influence the ski gliding properties. Though it seems quite feasible that the control of the cross country ski vibrations can improve the gliding performance, further systematic studies are needed to confirm it and to formulate the consecutive strategies of cross country ski design improvement.

  • 47.
    Kuzmin, Leonid
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    The relationship between the type of machining of the ski running surface and its wettability and capillary drag2010Inngår i: Sports Technology, ISSN 1934-6182, E-ISSN 1934-6190, Vol. 3, nr 2, s. 121-130Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper considers the mechanically treated dry ski running surface. The difference in the shear wettability of ski running surfaces treated using different types of machining was studied by measuring the advanced and receding contact angles on two different ski base materials. The hypothesis regarding relationship between the shear wettability and the capillary drag of ski running surface have been presented. The study found, that ski running surfaces with a lower roughness (e.g. flattened by a steel drum or sliced) have a lower wettability factor and seem to be more effective in reducing capillary drag under homogenous wetting conditions.

  • 48.
    Kuzmin, Leonid
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Danvind, Jonas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling.
    Estimating surface hydrophobicity by introducing a wettability factor based on contact anglesManuskript (preprint) (Annet vitenskapelig)
  • 49.
    Sundström, David
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Bäckström, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    A four compartment model on human exercise bioenergetics2015Inngår i: Procedia Engineering / [ed] A. Subic, F.K. Fuss, F. Alam, T.Y. Pang and M. Takla, Elsevier, 2015, Vol. 112, s. 4-9Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Performance in endurance sports depends on the athlete's ability to generate power output through muscle contraction. The energy requirements of muscles are satisfied by the alactic and lactic bioenergetic pathways, working anaerobically, and the aerobic oxidative phosphorylation of fats and carbohydrates. The aim of this study was to apply further extensions to hydraulic bioenergetic modelling to better describe the regulation of oxidative fuel selection. For this reason, a four compartment bioenergetic model was introduced and regulation of fat and carbohydrate oxidation was implemented. Further regulation was applied to both oxidative fuel selection and anaerobic glycolysis to depend on the current carbohydrate store. The model was formulated mathematically as differential equations, which were solved numerically to perform simulations of human bioenergetics in exercise. Simulation results showed good consistency with experimental findings.

  • 50.
    Sundström, David
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Bäckström, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Carlsson, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Tinnsten, Mats
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Optimal distribution of power output and braking for corners in road cycling2015Konferansepaper (Fagfellevurdert)
12 1 - 50 of 61
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf