Diffusion tensor imaging is associated with motor outcomes of very preterm born children at 11 years of age

Aim Very preterm children born Methods A cohort of 37 very preterm infants (mean gestational age 29 4/7, SD 2 0/7) born in 2004-2006 in Turku University Hospital underwent diffusion tensor imaging at term. A region of interest analysis of fractional anisotropy and mean diffusivity was performed. Motor outcomes at 11 years of age were measured with the Movement Assessment Battery for Children - Second Edition. Results The diffusion metrics of the corpus callosum (genu P = .005, splenium P = .049), the left corona radiata (P = .035) and the right optic radiation (P = .017) were related to later motor performance. Mean diffusivity decreased and fractional anisotropy increased in proportion to the improving performance. Conclusion The diffusion metrics of the genu and splenium of the corpus callosum, the left corona radiata and the right optic radiation at term were associated with motor skills at 11 years of age. Diffusion tensor imaging should be further studied as a potential tool in recognising children at risk for motor impairment.</div

Condition monitoring of railway vehicles : a study on wheel condition for heavy haul rolling stock

A railway is an energy efficient mode of transport as it uses the low resistance contact between wheel and rail. This contact is not frictionless and causes wear on both surfaces. The wheel-rail guidance is made possible by the shapes of wheel and rail profiles. To increase revenue for train operators and decrease cost for railway infrastructure owners, there is a need to monitor the conditions of the assets. A major cost-driver for operators is the production loss due to wheels, especially from maintenance costs when changing and re-profiling wheels.The research in this study has been performed on the Iron Ore Line (malmbanan) in northern Sweden and Norway. Large parts of this railway line are situated north of the Arctic Circle with temperature variations from -40◦C to +25◦C and a yearly average around freezing. Running trains in this environment strains all components. The purpose of this research is to evaluate how condition-based maintenance should be implemented for railway wagons. Research methods include a literature review, interviews, and data collection and analysis. Manual wheel profile measurements have been combined with maintenance data, weather data and wheel-rail force measurements to make comparisons between seasons and wagons.The analysis shows that there are different lateral force signatures at the wheel-rail interface dependent on the wheel’s position within the bogie. It also shows the need to change both wheel sets of the bogie simultaneously. Finally, it proves there is greater wheel wear at low temperatures.Godkänd; 2012; 20120215 (mikpal); LICENTIATSEMINARIUM Ämnesområde: Drift och underhållsteknik/Operation and Maintenance Examinator: Professor Uday Kumar, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Diskutant: CI Teknisk chef Thomas Robertsson, Euromaint Rail AB, Solna Tid: Fredag den 30 mars 2012 kl 10.15 Plats: F1031, Luleå tekniska universite

Driftsäker kapacitet med effektivt tillståndsbaserat underhåll för järnvägsfordon

All businesses need equipment to deliver services or manufacture goods. Over time, this equipment will degrade, but with proper maintenance, the degradation can be controlled, and failed equipment can be restored to operational status. Run-to-failure maintenance is performed when equipment or systems break down. In preventive maintenance, equipment is maintained as a precautionary measure to prevent failure. Finally, condition-based maintenance recommends maintenance actions based on the condition of the asset.The railway is a superior mode of transport if capacity, speed and environment are the main criteria; it also plays a crucial role in heavily crowded regions. The condition of the wheels and the rails affects rail- way safety, and infrastructure regulators and managers are always trying to reduce potential risk areas. The wheel-rail interface triggers most of the cost for maintenance.The railway wagons in this research use a time-based maintenance strategy, a strategy which does not fully consider the actual health of the asset. However, by using condition data from observations, along with diagnostics and prognostics, an effective condition-based maintenance strategy can be planned effectively way and executed efficiently.The results of this research suggest the efficacy of using automatic condition monitoring systems to increase the amount of available data for analysis and maintenance support planning, rather than depending on a system where operators or maintenance personnel do the measurements. The results also indicate that continuous monitoring of lateral forces will decrease the risk of derailment.Condition monitoring data can support maintenance preparation, assessment, and improvements and help to form a continuous improvement loop. This, plus a condition-based maintenance strategy, will lead to capacity assurance.Godkänd; 2014; 20131125 (mikpal); Tillkännagivande disputation 2014-01-07 Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Mikael Palo Ämne: Drift och underhållsteknik/Operation and Maintenance Avhandling: Condition-Based Maintenance for Effective and Efficient Rolling Stock Capacity Assurance A Study on Heavy Haul Transport in Sweden Opponent: Professor Doug Hargreaves, Science and Engineering Faculty, Queensland University of Technology, Australia Ordförande: Professor Uday Kumar, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Måndag den 3 februari 2014, kl 10.00 Plats: C305, Luleå tekniska universite

Hur ett företag inom upplevelseindustrin stärker sitt varumärke : en fallstudie av Brändö Konferens & Fritidsby

Validerat; 20101217 (root

Hur ett industriföretag ökar kundvärdet genom tilläggstjänster

Validerat; 20101217 (root

Condition monitoring of rolling stock using wheel/rail forces

Railway vehicles are efficient because of the low resistance in the contact zonebetween wheel and rail. In order to remain efficient both train operators and infrastructureowners need to keep rails, wheels and vehicles in acceptable condition. Wheelwear affects the dynamic characteristics of vehicles and the dynamic force impact onthe rail.The shape of the wheel profile affects the performance of railway vehicles in differentways. Wheel condition has historically been managed by identifying and removingwheels from service when they exceed an impact threshold. Condition monitoring ofrailway vehicles is mainly performed using wheel impact load detectors and truck performancedetectors. These systems use either forces or stress on the rail to interpretthe condition.This paper will show measurements taken at the research station outside Luleå innorthern Sweden. The station measures the wheel/rail forces, both lateral and vertical,at the point of contact in a curve with 484 m radius at speeds up to 100 km/h. Dataare analyzed to show differences for various wheel positions and to determine therobustness of the system.Godkänd; 2012; Bibliografisk uppgift: CD-ROM; 20120823 (mikpal

Från mätdata till underhållsbeslut : hjulslitage och spårkrafter

Denna rapport beskriver resultaten från projektet ”Från mätdata till underhållsbeslut” där avdelningen för drift och underhållsteknik/JVTC vid Luleå tekniska universitet på uppdrag av MTAB följt hjulslitaget på två malmvagnar under ett års tid. Under perioden har vagnarnas rälkrafter registrerats vid JVTC:s forskningsstation i Sävast.Godkänd; 2011; 20131121 (mikpal)</p

Potential reliability improvements for SSAB railway transport

Godkänd; 2012; 20121015 (mikpal)</p

Holistic maintenance information with multi-layers of contractors

Godkänd; 2012; 20121214 (andbra)</p