Warranty Prediction Using Weibull Simulation

The main objective of this master’s thesis is to examine if Weibull analysis is suitable method for warranty forecasting in the Case Company. The Case Company has used Reliasoft’s Weibull++ software, which is basing on the Weibull method, but the Company has noticed that the analysis has not given right results. This study was conducted making Weibull simulations in different profit centers of the Case Company and then comparing actual cost and forecasted cost. Simula-tions were made using different time frames and two methods for determining future deliveries. The first sub objective is to examine, which parameters of simulations will give the best result to each profit center. The second sub objective of this study is to create a simple control model for following forecasted costs and actual realized costs. The third sub objective is to document all Qlikview-parameters of profit centers. This study is a constructive research, and solutions for company’s problems are figured out in this master’s thesis. In the theory parts were introduced quality issues, for example; what is quality, quality costing and cost of poor quality. Quality is one of the major aspects in the Case Company, so understand-ing the link between quality and warranty forecasting is important. Warranty management was also introduced and other different tools for warranty forecasting. The Weibull method and its mathematical properties and reliability engineering were introduced. The main results of this master’s thesis are that the Weibull analysis forecasted too high costs, when calculating provision. Although, some forecasted values of profit centers were lower than actual values, the method works better for planning purposes. One of the reasons is that quality improving or alternatively quality decreasing is not showing in the results of the analysis in the short run. The other reason for too high values is that the products of the Case Company are com-plex and analyses were made in the profit center-level. The Weibull method was developed for standard products, but products of the Case Company consists of many complex components. According to the theory, this method was developed for homogeneous-data. So the most im-portant notification is that the analysis should be made in the product level, not the profit center level, when the data is more homogeneous.

Prediction of neurodevelopment and neuromotor trajectories in very preterm born children up to 11 years of age: PIPARI Study

Very preterm birth is a risk for brain injury and abnormal neurodevelopment. While the incidence of cerebral palsy has decreased due to advances in perinatal and neonatal care, the rate of less severe neuromotor problems continues to be high in very prematurely born children. Neonatal brain imaging can aid in identifying children for closer follow-up and in providing parents information on developmental risks. This thesis aimed to study the predictive value of structural brain magnetic resonance imaging (MRI) at term age, serial neonatal cranial ultrasound (cUS), and structured neurological examinations during the longitudinal follow-up for the neurodevelopment of very preterm born children up to 11 years of age as a part of the PIPARI Study (The Development and Functioning of Very Low Birth Weight Infants from Infancy to School Age). A further aim was to describe the associations between regional brain volumes and long-term neuromotor profile. The prospective follow-up comprised of the assessment of neurosensory development at 2 years of corrected age, cognitive development at 5 years of chronological age, and neuromotor development at 11 years of age. Neonatal brain imaging and structured neurological examinations predicted neurodevelopment at all age-points. The combination of neurological examination and brain MRI or cUS improved the predictive value of neonatal brain imaging alone. Decreased brain volumes associated with neuromotor performance. At the age of 11 years, the majority of the very preterm born children had age-appropriate neuromotor development and after-school sporting activities. Long-term clinical follow-up is recommended at least for all very preterm infants with major brain pathologies.