Guntram Berti

Dr. Guntram Berti Consulting Mathematical Methods · Freelancer

Although, many applications use unstructured meshes, there is no specialized mesh database which supports storing and querying mesh data. Existing mesh libraries do not support declarative querying and are expensive to maintain. A mesh database can benefit the domains in several ways such as: declarative query language, ease of maintenance, etc. In...

Computer simulation plays an increasingly important role in the area of medical physics. The coupled simulation of blood flow, species transport and biological processes in patient specific vessel geometries is a rapidly growing field with the ambitious goal to help clinicians with risk prediction and treatment planning, for example in the case of...

The understanding of biological processes, e.g. related to cardio-vascular disease and treatment, can significantly be improved by numerical simulation. In this paper, we present an approach for a multiscale simulation environment, applied for the prediction of in-stent re-stenos is. Our focus is on the coupling of distributed, heterogeneous hardwa...

Cerebral aneurysms are a multi-factorial disease with severe consequences. A core part of the European project @neurIST was the physical characterization of aneurysms to find candidate risk factors associated with aneurysm rupture. The project investigated measures based on morphological, haemodynamic and aneurysm wall structure analyses for more t...

The increasing volume of data describing human disease processes and the growing complexity of understanding, managing, and sharing such data presents a huge challenge for clinicians and medical researchers. This paper presents the @neurIST system, which provides an infrastructure for biomedical research while aiding clinical care, by bringing toge...

Supplementary material contains questionnaire with the complete list of questions.

The importance of hemodynamics in the etiopathogenesis of intracranial aneurysms (IAs) is widely accepted. Computational fluid dynamics (CFD) is being used increasingly for hemodynamic predictions. However, alogn with the continuing development and validation of these tools, it is imperative to collect the opinion of the clinicians. A workshop on C...

The first part of this paper presents a selection of medical simulation applications, including image reconstruction, near real-time registration for neuro-surgery, enhanced dose distribution calculation for radio-therapy, inhaled drug delivery prediction, plastic surgery planning and cardio-vascular system simulation. The latter two topics are dis...

Mesh generation in finite-element- (FE) method-based electroencephalography (EEG) source analysis generally influences greatly the accuracy of the results. It is thus important to determine a meshing strategy well adopted to achieve both acceptable accuracy for potential distributions and reasonable computation times and memory usage. In this paper...

Alloplastic CAM-CAM manufactured implants are regularly used to cover bony defects of the skull in craniomaxillofacial surgery. Regarding unilateral “simple” deficiencies, mirroring procedures can be successfully employed for construction. In cases of complex and bilateral defects resp. syndromic malformations, planning can only be performed accord...

We discuss the mesh-partitioning load-balancing problem for non-homogeneous communication systems, and investigate whether the MPI process topology functionality can aid in solving the problem. An example kernel shows that specic communication patterns can benet substantially from a non-trivial MPI topology implementation, achieving improvements be...

In the reconstruction of complex craniofacial malfor-mations CAD-CAM procedures could help generating alloplastic implants to achieve almost optimal esthetic results. Complementary to the existing CAD-CAM techniques in the cranial vault region or modeling procedures in unilateral defects, these techniques are introduced to bilaterally affected skul...

Dedicated library support for mesh-level geometry components, central to numerical PDE solution, is scarce. We claim that the situation is due to the inadequacy of traditional design techniques for complex and variable data representations typical for meshes. As a solution, we introduce an approach based on generic programming, implemented in the C...

The European GEMSS Project is concerned with the creation of medical Grid service prototypes and their evaluation in a secure service-oriented infrastructure for distributed on demand/supercomputing. Key aspects of the GEMSS Grid middleware include negotiable QoS support for time-critical service provision, flexible support for business models, and...

Objectives: The European GEMSS Project is concerned with the creation of medical Grid service prototypes and their evaluation in a secure service-oriented infrastructure for distributed on demand/supercomputing. Key aspects of the GEMSS Grid middleware include negotiable QoS support for time-critical service provision, flexible support for business...

The European GEMSS Project is concerned with the creation of medical Grid service prototypes and their evaluation in a secure serviceoriented infrastructure for distributed ondemand supercomputing the GEMSS testbed. The medical prototype applications include maxillofacial surgery simulation, neurosurgery support, radiosurgery planning, inhaled drug...

We present a dimension-independent algorithm for non-uniform meshing of voxel geometries, e.g. stemming from segmented medical images. The basic algorithms uses spacetrees (generalized octrees for arbitrary dimension) to build a hierarchical representation of the image information. The resolution of the spacetree can depend on several parameters, s...

Malformations of the midface can be treated by distraction osteogenesis, i.e. cutting bones and pulling them into the right position. We present a computational toolchain helping to predict the eects of the surgery on the soft tissue displacement. An initial raw CT image is segmented and transformed into a geometric head model, which is used for vi...

Objectives: Grid Enabled Medical Simulation Services (GEMSS) aims to provide a health-computing Grid platform suited to the provision of accessible compute-intensive health applications. The viability and performance of the Grid resource is to be tested using a series of six applications, intended to highlight strengths and weaknesses of the Grid i...

Objectives: The European GEMSS Project is concerned with the creation of medical Grid service prototypes and their evaluation in a secure service-oriented infrastructure for distributed on demand/supercomputing. Key aspects of the GEMSS Grid middleware include negotiable QoS support for time-critical service provision, flexible support for business...

GEMSS is a European project that aims at providing high performance medical simulation services in a distributed and grid computing environment. The GEMSS grid middleware is designed using web services technologies and standards and provides support for authorization, workflow, security, Quality of Service aspects. In this work, one of the GEMSS ap...

As the Internet revolutionised access to information, the Grid will revolutionise access to computer applications and software systems. In general, this includes the highly important aspect of access to information resources such as Grid database systems (datadriven Grid applications), but we concentrate here on computational services providing num...

The European GEMSS Project is concerned with the creation of medical Grid service prototypes and their evaluation in a secure serviceoriented infrastructure for distributed ondemand supercomputing the GEMSS testbed. The medical prototype applications include maxillofacial surgery simulation, neurosurgery support, radiosurgery planning, inhaled drug...

As the Internet revolutionised access to information, the Grid will revolutionise access to computer applications and software systems. In general, this includes the highly important aspect of access to information resources such as Grid database systems (datadriven Grid applications), but we concentrate here on computational services providing num...

The central objective of the SimBio§ project is the improvement of clinical and medical practices by the use of large-scale numerical simulation for bio-medical problems. SimBio provides a generic simulation environment running on parallel and distributed computing systems, An innovative key feature is the input of patient specific data to the mode...

The SimBio† project provides a generic simulation environment for advanced clinical practice and health care. A key feature is the input of individual patient data to the modeling and simulation process. The project evaluation & validation will demonstrate improvements in non-invasive diagnosis, pre-operative planning and design of prostheses. The...

Dedicated library support for mesh-level geometry compo- nents, central to numerical PDE solution, is scarce. We claim that the situation is due to the inadequacy of traditional design techniques for complex and variable data representations typical for meshes. As a so- lution, we introduce an approach based on generic programming, imple- mented in...

Geometric functionality is crucial for a variety of application domains, including computational mechanics. Typically, geometric tasks are embedded into a larger problem frame. Due to the diversity of tasks, geometric tools must often be combined to achieve the desired solution. As implementing geometric algorithms is difficult and time-consuming,...

Universally reusable tools for grid management tasks are scarce. We identify coupling of algorithms to data structures as main obstacle for reuse, and show how to overcome the difficulties by using generic programming. After introducing an abstract kernel of grid functionality, we present some universal generic grid tools based on that kernel which...

The local data dependency pattern or stencil of a numerical algorithm is a structural property which is important for parallel computations. We present an algebraic notation for stencils on unstructured grids, derive some basic properties of stencils, and introduce two algorithms for constructing grid overlaps based on stencils. Finally, we show ho...

Grids are fundamental data structures for representing geometric structures or their subdivisions. We propose a strategy for decoupling algorithms working on grids from the details of grid representations, using a generic programming approach in C++. Functionality of grid data structures is captured by a small set of primitives, divided into combin...

In my dissertation, I tackled two problems: First, how can algorithms operating on grids (or meshes) be implemented in a way that is independent of the concrete representation of a grid, and at the same time, sufficiently efficient? Second, how can the paradigm of geometric partitioning (domain decomposition) which is used for distributed execution...

The parallelization of numerical codes on unstructured grids still is a demanding programming task, which is often performed in an application-specific manner. However, many of the algorithms used in this field exhibit strong structural similarities. A concept exploiting the latter is developed in this paper. Furthermore, it will be shown how the a...

Controlling parameters is a necessity in every non-trivial application. We present a pattern that aids in decoupling external control mechanics from the internal component structure, while supporting the automatic mirroring of internal structure into external representation. Furthermore, we show how to use this pattern in the implementation of a C+...

We consider a generalized system of Euler equations that describes the inviscid ow of a mixture of diierent gases. Systems of conservation laws of this type occur typically in the context of the numerical simulation of reacting gas ows. Results concerning the mathematical properties of the above model are presented. It turns out that a simple prope...

this paper. A more detailed elaboration of these topics will be given in [4]