177 research outputs found

    A comparison of semiglobal and local dense matching algorithms for surface reconstruction

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    Encouraged by the growing interest in automatic 3D image-based reconstruction, the development and improvement of robust stereo matching techniques is one of the most investigated research topic of the last years in photogrammetry and computer vision. The paper is focused on the comparison of some stereo matching algorithms (local and global) which are very popular both in photogrammetry and computer vision. In particular, the Semi-Global Matching (SGM), which realizes a pixel-wise matching and relies on the application of consistency constraints during the matching cost aggregation, will be discussed. The results of some tests performed on real and simulated stereo image datasets, evaluating in particular the accuracy of the obtained digital surface models, will be presented. Several algorithms and different implementation are considered in the comparison, using freeware software codes like MICMAC and OpenCV, commercial software (e.g. Agisoft PhotoScan) and proprietary codes implementing Least Square e Semi-Global Matching algorithms. The comparisons will also consider the completeness and the level of detail within fine structures, and the reliability and repeatability of the obtainable data

    The frequency of endometriosis in the general and selected populations: A systematic review

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    Background: In this article, we have reviewed available data on the frequency of endometriosis considering separately the incidence and the prevalence of the disease using data from papers published from 2000 to June 2019. Study design: Systematic review and meta-analysis. PubMed and EMBASE were searched for observational studies reporting data on the incidence or prevalence rates or ratios for the following pre-speci\ufb01ed populations: general population, infertile women, women reporting pelvic pain, women who underwent pelvic surgical procedures unrelated with endometriosis. Results: A total of 42 papers were included in this review. Considering the 11 studies that have analysed the prevalence of endometriosis in the general population, the reported prevalence ranged from 0.8% to 28.6% with an overall estimated of 4.4% (95% CI 3.6\u20135.2). When we considered separately the estimates reported in each study according to geographic area, the pooled estimate was lower in the European studies (1.4%), increased to 5.7% in the US studies and was 15.4% in the Asian ones. The pooled estimated prevalence of endometriosis was 33.5% (95% CI 24.3\u201342.8, Figure 2(c)) in women who underwent surgery for benign gynaecological conditions, 23.8% (95% CI 16.1\u201331.5, Figure 2(d)) in infertile women, and 49.7 % (95% CI 14.4\u201385.0) in women with chronic pelvic pain. Conclusion: This review offers an overview of the available data on the frequency of endometriosis in the general population and in selected population, in particular among infertile women and women with chronic pelvic pain

    Thermal, electric and durability characterization of supercaps for energy back-up of automotive ECU

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    A new generation of mechatronic devices, such as the E-latch for door closure, is introduced in the automotive field to replace mechanical systems with electro-actuated parts with embedded electronic control unit (ECU) connected to the main vehicle network. Due to severe automotive safety-critical requirements an energy back-up solution is proposed, based on supercaps and boost converter, to ensure E-latch operation even in case of main battery failure. An in-depth thermal, electrical and durability characterization of the supercaps proves the suitability of the energy back-up unit for automotive applications

    New experimental techniques for fracture testing of highly deformable materials

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    A new experimental method for measuring strain fields in highly deformable materials has been developed. This technique is based on an in-house developed Digital Image Correlation (DIC) system capable of accurately capturing localized or non-uniform strain distributions. Thanks to the implemented algorithm based on a Semi-Global Matching (SGM) approach, it is possible to constraint the regularity of the displacement field in order to significantly improve the reliability of the evaluated strains, especially in highly deformable materials. Being originally introduced for Digital Surface Modelling from stereo pairs, SGM is conceived for performing a one-dimensional search of displacements between images, but here a novel implementation for 2D displacement solution space is introduced. SGM approach is compared with the previously in-house developed implementation based on a local Least Squares Matching (LSM) approach. A comparison with the open source code Ncorr and with some FEM results is also presented. The investigation using the present DIC method focuses on 2D full-field strain maps of plain and notched specimens under tensile loading made of two different highly deformable materials: hot mix asphalt and thermoplastic composites for 3D-printing applications. In the latter specimens, an elliptical hole is introduced to assess the potentiality of the method in experimentally capturing high strain gradients in mixed-mode fracture situations

    25-Hydroxyvitamin D Serum Levels and Endometriosis : Results of a Case–Control Study

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    The immunomodulatory, anti-inflammatory, and antiproliferative properties of vitamin D have laid the basis for a possible function of this prohormone in the pathogenesis of endometriosis. The aim of this case\u2013control study was to investigate vitamin D status, by measuring 25-hydroxyvitamin D [25(OH)D] serum levels, in women with and without endometriosis. Only Italian women of Caucasian origin aged between 18 and 45 years were deemed eligible. Enrollment was limited to the period October to May. Cases and controls were matched for month of recruitment and secondarily for age and parity. Overall, 434 women were enrolled (endometriosis n = 217; controls n = 217). The group of cases included 127 women with ovarian endometrioma and 90 patients with deep endometriosis. Mean (standard deviation) levels of 25(OH)D in women with and without endometriosis were 17.9 (7.0) ng/mL and 18.4 (7.6) ng/mL, respectively (P =.46). Analyzing the two endometriosis subgroups separately, no statistically significant differences emerged (18.7 [7.4] ng/mL in deep endometriosis group vs 17.3 [6.6] ng/mL in women with ovarian endometrioma; P =.14). Comparing the subgroup of women with deep endometriosis with paired controls, no differences occurred (18.7 [7.4] ng/mL vs 18.5 [7.7] ng/mL, P =.80). Similar data emerged when performing the same analysis for ovarian endometriomas (17.4 [6.6] ng/mL vs 18.3 [7.6] ng/mL, P =.23). The results of the present case\u2013control study do not support an association between serum vitamin D levels and different phenotypes of endometriosis

    USE OF UAS IN A HIGH MOUNTAIN LANDSCAPE: THE CASE OF GRAN SOMMETTA ROCK GLACIER (AO)

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    Photogrammetry has been used since long time to periodically control the evolution of landslides, either from aerial images as well as from ground. Landslides control and monitoring systems face a large variety of cases and situations: in hardly accessible environments, like glacial areas and high mountain locations, it is not simple finding a survey method and a measurement control system, which are capable to reliably assess, with low costs, the expected displacement and its accuracy. For this reason, the behaviour of these events presents the geologists and the surveyor each time with different challenges. The use of UAS (Unmanned Aerial System) represents, in this context, a recent and valid option to perform the data acquisition both in safety and quickly, avoiding hazards and risks for the operators while at the same time containing the costs. The paper presents an innovative monitoring system based on UAS-photogrammetry, GNSS survey and DSM change detection techniques to evaluate the Gran Sommetta rock glacier surface movements over the period 2012-2014. Since 2012, the surface movements of the glacier are monitored by ARPAVdA (a regional environmental protection agency) as a case study for the impact of climate change on high-mountain infrastructures. In such scenarios, in fact, a low-cost monitoring activity can provide important data to improve our knowledge about glacier dynamics connected to climate changes and to prevent risks in anthropic Alps areas. To evaluate the displacements of the rock glacier different techniques were proposed: the most reliable uses the orthophoto of the area and rely on a manual identification of corresponding features performed by a trained operator. To further limit the costs and improve the density of displacement information two automatic procedures were developed as well

    Segmental Liver Transplantation From Living Donors Report of the Technique and Preliminary Results in Dogs

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    A technique of orthotopic liver transplantation using a segmental graft from living donors was developed in the dog. Male mongrel dogs weighing 25–30 kg were used as donors and 10–15 kg as recipients. The donor operation consists of harvesting the left lobe of the liver (left medial and left lateral segments) with the left branches of the portal vein, hepatic artery and bile duct, and the left hepatic vein. The grafts are perfused in situ through the left portal branch to prevent warm ischemia. The recipient operation consists of two phases: 1total hepatectomy with preservation of the inferior vena cava using total vascular exclusion of the liver and veno-venous bypass, 2implantation of the graft in the orthotopic position with anastomosis of the left hepatic vein to the inferior vena cava and portal, arterial and biliary reconstruction. Preliminary experiments consisted of four autologous left lobe transplants and nine non survival allogenic left lobe transplants. Ten survival experiments were conducted. There were no intraoperative deaths in the donors and none required transfusions. One donor died of sepsis, but all the other donor dogs survived without complication. Among the 10 grafts harvested, one was not used because of insufficient bile duct and artery. Two recipients died intraoperatively of air embolus and cardiac arrest at the time of reperfusion. Three dogs survived, two for 24 hours and one for 48 hours. They were awake and alert a few hours after surgery, but eventually died of pulmonary edema in 2 cases and of an unknown reason in the other. Four dogs died 2–12 hours postoperatively as a result of hemorrhage for the graft's transected surface. An outflow block after reperfusion was deemed to be the cause of hemorrhage in these cases. On histologic examination of the grafts, there were no signs of ischemic necrosis or preservation damage

    Advances in Li-Ion battery management for electric vehicles

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    This paper aims at presenting new solutions for advanced Li-Ion battery management to meet the performance, cost and safety requirements of automotive applications. Emphasis is given to monitoring and controlling the battery temperature, a parameter which dramatically affects the performance, lifetime, and safety of Li-Ion batteries. In addition to this, an innovative battery management architecture is introduced to facilitate the development and integration of advanced battery control algorithms. It exploits the concept of smart cells combined with an FPGA-based centralized unit. The effectiveness of the proposed solutions is shown through hardware-in-the-loop simulations and experimental results

    Quality of life and satisfaction of patients after oncoplastic or traditional breast-conserving surgery using the BREAST-Q (BCT module): a prospective study

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    Introduction: The oncoplastic conservative surgery was developed as a natural evolution of traditional surgery, attempting to improve the therapeutic and aesthetic outcomes where tumor resection could be followed by not-adequate results. Our primary aim is to evaluate how patient satisfaction and quality-of-life after conservative oncoplastic surgery, using BREAST-Q (BCT Module), change pre- and post-operatively. The secondary aim is to compare patient-reported outcome after oncoplastic or traditional conservative surgery. Patients and methods: We enrolled 647 patients who underwent traditional conservative surgery or oncoplastic surgery from January 2020 to December 2022. Only 232 women (35.9%) completed the BREAST-Q questionnaire on a web-based platform, at the preoperative phase and 3 months after treatment. Results: The average score of "Psychosocial well-being" and "Satisfaction with Breasts" 3 months after surgery showed a statistically significant improvement, while the average score for "Physical well-being: Chest" at 3 months showed a worsening compared to the baseline. "Sexual well-being" did not show statistically significant change. A significant difference between the post-operative outcome of oncoplastic surgery and traditional surgery was observed only for Physical well-being (better for traditional surgery). Conclusions: The study showed significant improvement in patient-reported outcomes 3 months after the surgery, except for physical discomfort that increases especially after oncoplastic surgery. Furthermore, our data, as well as many others, point to the appropriateness of using OCS where there is an effective indication, while the perspective of patients cannot find significant superiority over TCS in any of the areas analyzed
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