7 research outputs found
User Choices for Efficient 3D Motion and Shape Extraction from Orthographic Projections
The problem of estimating three dimensional motion and structure of objects from monoc-ular image sequences has drawn particular attention since the past decade. The extraction of structure-from-motion emerges in research elds such us computer vision, video coding, biomedical engineering and human-computer interaction. Present work focuses on the algorithmic approach of structure-from-motion under orthography providing, at the same time, guidelines in matters of implementation. Relative principles, constraints and stability matters are discussed. Asymptotic behaviour and consistency of the proposed estimators is analyzed in [12]. The improvement of the algorithm's performance w.r.t. the proposed user-choices is illustrated by means of experimental results
A Multiresolution Approach for Main Mobile Object Localization
Main mobile object localization is a task that emerges in research fields such us video understanding, object-based coding and various related applications, such as contentbased retrieval, remote surveillance and object recognition. The present work revisits mobile object localization in the context of content-based retrieval schemes and the related MPEG-7 framework, for natural and synthetic, indoor and outdoor sequences, when either a static or a mobile camera is utilized. The proposed multiresolution approach greatly improves the trade-off between accuracy and timeperformance leading to satisfactory results with a considerably low amount of computations. Moreover, based on the point gatherings extracted in [14], the bounding polygon and the direction of movement are estimated for each mobile object; thus yielding an adequate representation in the MPEG-7 sense. Finally, the resulting polygons can be used as appropriate initial estimates for methods that extract object contours, e.g. curve propagation approaches, such as [8,10] which utilize the level-set method. Experimental results over a number of distinct natural sequences have been included to illustrate the performance of the proposed approach. 1
Emergency liver resection for combined biliary and vascular injury following laparoscopic cholecystectomy: Case report and review of the literature
A 75-year-old woman suffering from symptomatic cholelithiasis was
admitted to our hospital for elective laparoscopic cholecystectomy (LC).
Intraoperatively, because of severe inflammation and dense adhesions in
the region of the Calot triangle and bleeding arising from the porta
hepatis which obscured the operating field, the method was converted to
a conventional open approach. Copious hemostasis was achieved using
sutures, clips and diathermy, and no bile duct or vascular injuries were
recognized intraoperatively. Because of severe right upper quadrant
abdominal pain and significant deterioration of the liver function tests
(LFTs) on the first postoperative day, the patient underwent a Doppler
ultrasound scan which showed absence of blood flow at the level of porta
hepatis. Urgent relaparotomy revealed an ischemic liver on the right, a
transected common bile duct at the level of its confluence, a divided
and ligated right hepatic artery and thrombosed portal vein down to its
confluence. Thrombectomy and reconstruction of the portal vein were
performed to salvage the left hemiliver, and after restoration of blood
flow to the left hemiliver, a right hemihepatectomy and a Roux-en-Y
hepaticojejunostomy on the left were performed