Dienst van SURF
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In this paper, we address the problem of people detection and tracking in crowded scenes using range cameras. We propose a new method for people detection and localisation based on the combination of background modelling and template matching. The method uses an adaptive background model in the range domain to characterise the scene without people. Then a 3D template is placed in possible people locations by projecting it in the background to reconstruct a range image that is most similar to the observed range image. We tested the method on a challenging outdoor dataset and compared it to two methods that each shares one characteristic with the proposed method: a similar template-based method that works in 2D and a well-known baseline method that works in the range domain. Our method performs significantly better, does not deteriorate in crowded environments and runs in real time.
Introduction: The purpose of this review is to gather and analyse current research publications to evaluate Sinogram-Affirmed Iterative Reconstruction (SAFIRE). The aim of this review is to investigate whether this algorithm is capable of reducing the dose delivered during CT imaging while maintainingimage quality. Recent research shows that children have a greater risk per unit dose due to increased radiosensitivity and longer life expectancies, which means it is particularly important to reduce the radiation dose received by children.Discussion: Recent publications suggest that SAFIRE is capable of reducing image noise in CT images, thereby enabling the potential to reduce dose. Some publications suggest a decrease in dose, by up to 64% compared to filtered back projection, can be accomplished without a change in image quality.However, literature suggests that using a higher SAFIRE strength may alter the image texture, creating an overly ‘smoothed’ image that lacks contrast. Some literature reports SAFIRE gives decreased low contrast detectability as well as spatial resolution. Publications tend to agree that SAFIRE strength threeis optimal for an acceptable level of visual image quality, but more research is required. The importance of creating a balance between dose reduction and image quality is stressed. In this literature review most of the publications were completed using adults or phantoms, and a distinct lack of literature forpaediatric patients is noted.Conclusion: It is necessary to find an optimal way to balance dose reduction and image quality. More research relating to SAFIRE and paediatric patients is required to fully investigate dose reduction potential in this population, for a range of different SAFIRE strengths.
Background: Deep inferior epigastric perforator (DIEP) flap breast reconstruction leads to large scars in the breast and abdominal region. Common symptoms related to abdominal scarring include changes in color, stiffness, thickness, and irregularity of the skin. The aim of this study was to examine whether microneedling improves the abdominal scar quality after DIEP-flap breast reconstruction. Methods: A prospective randomized controlled within subject comparison design (N = 30) was used to study the effect of microneedling treatments on the abdominal scar, versus no treatment. Three electrically powered microneedling sessions were performed every 4 weeks on one side of the abdominal scar. Abdominal scar assessment was performed at baseline and 3-, 6-, and 9-month follow-up using the Patient and Observer Scar Assessment Scale (POSAS). Treated and untreated sides were compared using a t test or Wilcoxon signed-rank test in case the data were not normally distributed. Results: Twenty-seven women completed the study. Microneedling treatment led to lower POSAS scores compared with the untreated scar side after the 3- and 9-month follow-up. At the 9-month follow-up, the POSAS total score (Mdn = 17, interquartile range = 18.3 versus Mdn = 21.4, interquartile range = 17.5) was statistically lower for the treated side compared with the untreated side, implying a better-appraised scar quality. The observer POSAS total score was statistically lower for the treated side compared with the untreated side. Conclusions: Based on patient and observer ratings, overall abdominal scars after DIEP-flap surgery improve significantly after microneedling treatment. Scar symptoms reduce faster under the influence of microneedling treatment compared with no treatment.
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