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For long, face recognition has been a 2D discipline. However, 2D face recognition has shown to be extremely difficult to be robust against a.o. lighting conditions and pose variations (Phillips et al., 2003). At the same time, technological improvements are making 3D surface capturing devices affordable for security purposes. As a result of these recent developments face recognition shifts from 2D to 3D. This means that in the current state-of-the-art face recognition systems the problem is no longer the comparison of 2D color photos, but the comparison of (textured) 3D surface shapes. With the advent of the third dimension in face recognition, we think it is necessary to investigate the known surface representations from this point of view. Throughout recent decades, a lot of research focused on finding an appropriate digital representation for three dimensional real-world objects, mostly for use in computer graphics (Hubeli & Gross, 2000; Sigg, 2006). However, the needs for a surface representation in computer graphics, where the primary concerns are visualization and the ability to process it on dedicated computer graphics hardware (GPUs), are quite different from the needs of a surface representation for face recognition. Another motivation for this work is the non-existence of an overview of 3D surface representations, altough the problem of object representation is studied since the birth of computer vision (Marr, 1982). With this in mind, we will, in this chapter, try to give an overview of surface representations for use in biometric face recognition. Also surface representations that are not yet reported in current face recognition literature, but we consider to be promising for future research – based on publications in related fields such as 3D object retrieval, computer vision, computer graphics and 3D medical imaging – will be discussed. What are the desiderata for a surface representation in 3D face recognition? It is certainly useful for a surface representation in biometric applications, to be accurate, usable for all sorts of 3D surfaces in face recognition (open, closed. . . ), concise (efficient in memory usage), easy to acquire/construct, intuitive to work with, have a good formulation, be suitable for computations, convertible in other surface representations, ready to be efficiently displayed and useful for statistical modelling. It is nevertheless also certainly necessary to look further than a list of desiderata. Herefore, our approach will be the following: we make a taxonomy of all surface representations within the scope of 3D face recognition. For each of the of the representations in this taxonomy, we will shortly describe the mathematical theory behind it. Advantages and disadvantages of the surface representation will be stated. Related research using these representations will be discussed and directions for future research will be indicated.

OBJECTIVES We evaluated the outcome of patients in cardiogenic shock receiving a paracorporeal pulsatile biventricular assist device as a bridge to transplantation. METHODS We performed a retrospective single-centre analysis of all patients who received a Berlin Heart Excor® at our institution between 2004 and 2019. RESULTS A total of 97 patients (90 adults, 7 paediatric) were analysed. Eighty-four patients were in Interagency Registry for Mechanically Assisted Circulatory Support level 1 (80 adults, 4 paediatric). Diagnoses were dilated cardiomyopathy (n = 41), ischaemic cardiomyopathy (n = 17) or myocardial infarction (n = 4), myocarditis (n = 15), restrictive cardiomyopathy (n = 2), graft failure after heart transplant (n = 7), postcardiotomy heart failure (n = 5), postpartum cardiomyopathy (n = 3), congenital heart disease (n = 1), valvular cardiomyopathy (n = 1) and toxic cardiomyopathy (n = 1). All patients were in biventricular heart failure and had secondary organ dysfunction. The mean duration of support was 63 days (0–487 days). There was a significant decrease in creatinine values after assist device implantation (from 1.83 ± 0.79 to 1.12 ± 0.67 mg/dl, P = 0.001) as well as a decrease in bilirubin values (from 3.94 ± 4.58 to 2.65 ± 3.61 mg/dl, P = 0.084). Cerebral stroke occurred in 16 patients, bleeding in 15 and infection in 13 patients. Forty-eight patients died on support, while 49 patients could be successfully bridged to transplantation. Thirty-day survival and 1-year survival were 70.1% and 41.2%, respectively. CONCLUSIONS A pulsatile biventricular assist device is a reasonable therapeutic option in cardiogenic shock, when immediate high cardiac output is necessary to rescue the already impaired kidney and liver function of the patient.

A core issue during the planning of a maintenance intervention in a facility with ionizing radiation is the minimization of the integrated equivalent dose contracted by the maintenance workers during the intervention. In this work, we explore the use of a technical-scientific software program facilitating the intervention planning in irradiated environments using sound mathematical concepts. We show how the software can be used in planning future operations using a case studies: the decommissioning of a beam dump for a linear 160 MeV H − accelerator. Interactive visualization of the facilities and radiation levels, as well as tools for interactive trajectory planning are explored, as well as automatic calculation of the expected integrated individual dose contracted during an intervention.

Novel Augmented Reality techniques have the potential to have a large positive impact on the way remote maintenance operations are carried out in hazardous areas, e.g. areas where radiation doses that imply careful planning and optimization of maintenance operations are present. This paper describes an Augmented Reality strategy, system and implementation for aiding the remote collimator exchange in the LHC, currently the world׳s largest and highest-energy particle accelerator. The proposed system relies on marker detection and multi-modal augmentation in real-time. A database system has been used to ensure flexibility. The system has been tested in a mock-up facility, showing real time performance and great potential for future use in the LHC. The technical-scientific difficulties identified during the development of the system and the proposed solutions described in this paper may help the development of future Augmented Reality systems for remote handling in scientific facilities.

International audience; A core issue during the planning of a maintenance intervention in a facility with ionizing radiation is the minimization of the integrated equivalent dose contracted by the maintenance workers during the intervention. In this work, we lay down the concepts for intervention planning in an irradiated environment and present a new software program for intervention planning, which provides interactive visualization of facilities and radiation levels, as well as tools for interactive trajectory planning. The software includes automatic calculation of the expected integrated equivalent radiation dose contracted during an intervention.

International audience; Intervention planning is crucial for maintenance operations in particle accelerator environments with ionizing radiation, during which the radiation dose contracted by maintenance workers should be reduced to a minimum. In this context, we discuss the visualization aspects of a new software tool, which integrates interactive exploration of a scene depicting an accelerator facility augmented with residual radiation level simulations, with the visualization of intervention data such as the followed trajectory and maintenance tasks. The visualization of each of these aspects has its effect on the final predicted contracted radiation dose. In this context, we explore the possible benefits of a user study, with the goal of enhancing the visual conditions in which the intervention planner using the software tool is minimizing the radiation dose.

Having reliable wireless communication in a network of mobile robots is an ongoing challenge, especially when the mobile robots are given tasks in hostile or harmful environments such as radiation environments in scientific facilities, tunnels with large metallic components and complicated geometries as found at CERN. In this paper, we propose a decentralised method for improving the wireless network throughput by optimizing the wireless relay robot position to receive the best wireless signal strength using implicit spatial diversity concepts and gradient-search algorithms. We experimentally demonstrate the effectiveness of the proposed solutions with a KUKA Youbot omni-directional mobile robot. The performance of the algorithms is compared under various scenarios in an underground scientific facility at CERN.

Currently, the recognition of faces under varying expressions is one of the main challenges in the face recognition community. In this paper a method is presented dealing with those expression variations by using an isometric deformation model. The method is built upon the geodesic distance matrix as a representation of the 3D face. We will show that the set of largest singular values is an excellent expression-invariant shape descriptor. Face comparison is performed by comparison of their shape descriptors using the mean normalized Manhattan distance as dissimilarity measure. The presented method is validated on a subset of 900 faces of the BU-3DFE face database resulting in an equal error rate of 13.37% for the verification scenario. This result is comparable with the equal error rates of other 3D expression-invariant face recognition methods using an isometric deformation model on the same database.

3D face recognition is a widely researched problem for wich many methods have been proposed. Unfortunately, most of these methods need vast prior knowledge in the form of large 3D face training sets. Also, many methods need point correspondences, which are hard to obtain. In this paper, we present a general 3D face recognition method based on point cloud kernel correlation and kernel density estimation for registration, which doesn't make use of a training set of faces or point correspondences and can handle noisy, unpreprocessed face scans. Initial experiments on the publicly available SHREC 2008 3D face database show good face recognition accuracy and robust behavior across face expressions.