Miodrag Manić

The Parametric Model of the Human Mandible Coronoid Process Created by Method of Anatomical Features.

Geometrically accurate and anatomically correct 3D models of the human bones are of great importance for medical research and practice in orthopedics and surgery. These geometrical models can be created by the use of techniques which can be based on input geometrical data acquired from volumetric methods of scanning (e.g., Computed Tomography (CT)) or on the 2D images (e.g., X-ray). Geometrical models of human bones created in such way can be applied for education of medical practitioners, preoperative planning, etc. In cases when geometrical data about the human bone is incomplete (e.g., fractures), it may be necessary to create its complete geometrical model. The possible solution for this problem is the application of parametric models. The geometry of these models can be changed and adapted to the specific patient based on the values of parameters acquired from medical images (e.g., X-ray). In this paper, Method of Anatomical Features (MAF) which enables creation of geometrically precise and anatomically accurate geometrical models of the human bones is implemented for the creation of the parametric model of the Human Mandible Coronoid Process (HMCP). The obtained results about geometrical accuracy of the model are quite satisfactory, as it is stated by the medical practitioners and confirmed in the literature.

IMPLANT MATERIAL SELECTION USING EXPERT SYSTEM

Most certainly, in the field of medicine there is a great contribution of new techniques and technologies, which is reflected in an entire system of health care services. Customized implants are both fully geometrically and topologically adjusted so as to meet the needs of individual patients, thus making each implant unique. Their production requires joint efforts of a multidisciplinary team of different profile experts who combine their knowledge in the Implant knowledge model. Thus, we develop an expert system which should help or replace humans in the process of Implant material selection. This paper gives an overview of the expert system concept for the given problem. Its task is to carry out a selection of biomaterial (or class of material) for a customized implant. The model significantly improves the efficiency of preoperative planning in orthopaedics.

Analysis of semantic features in free-form objects reconstruction

Abstract One of the biggest challenges associated with design and digital reconstruction of free forms comes from uniqueness and unrepeatability of these shapes. During digital reconstruction of these forms, the designer has to choose the right set of geometric features and then compose them in a way that will enable the most accurate reconstruction of the geometry. While doing this, the designer primarily relies on personal experience gained through work with free-form objects of similar geometry. In our opinion, the analysis of free-form objects geometry should rely upon semantic interpretation of their geometric and other features, and the greatest challenge of automation of digital reconstruction and free-form object design in general is closely related to automation of semantic interpretation of geometric and other free-form object features. In this paper, a case of chest bone implant digital reconstruction is presented, where a new semantic model called the active semantic model was used for modeling the meaning of geometric elements, that is, the semantic features of a free-form object. The active semantic model and its analogy-based reasoning algorithms have shown themselves as applicable for the automation of semantic interpretation of the unique, unrepeatable, and unpredictable forms of chest bone. Moreover, this semantic model showed the potential to help automate selecting and composing of geometric features for efficient digital reconstruction of the geometry of free forms.

Recognizing Topological Analogy in Semantic Network

Recognizing topological analogy between the parts of semantic network seems to be very important step in the process of semantic categorization and interpretation of data that are embedded into the semantic network. Considering the semantic network as a set of graphs, recognition of topological analogy between the parts of semantic network can be treated as maximum common subgraph problem which falls in the group of exact graph matching problems. In this paper authors propose a new algorithm for maximum common subgraph detection aimed to a specific semantic network called Active Semantic Model (ASM). This semantic network can be represented as the set of labeled directed multigraphs with unique node labels. The structure of these graphs is specific because associations or edges are labeled with several attributes and some of them are related to nodes connected by edge. That kind of association-oriented structure enables associations or edges to play key role in the process of semantic categorization and interpretation of data. Furthermore, this kind of structure enables modeling semantic contexts in a form of semantically designated graphs (of associations). Proposed algorithm is capable of recognizing simultaneously maximum common subgraph of input graph and each of the graphs representing different contexts in ASM semantic network.

IT Support for University Spin-Off Companies

Using information technologies can contribute significantly to the successful start of a company and its later progress. However, successful implementation is connected to certain expenses, which smaller companies (such as university spin-off companies) usually cannot afford. The analysis of existing approaches to implementation of IT and information systems will be performed in this chapter, along with the study of applicability of their use in university spin-off companies. As a conclusion, we will propose the best way to choose and use IT systems.

Software Framework for the Creation and Application of Personalized Bone and Plate Implant Geometrical Models

Computer-Assisted Orthopaedic Surgery (CAOS) defines a set of techniques that use computers and other devices for planning, guiding, and performing surgical interventions. The important components of CAOS are accurate geometrical models of human bones and plate implants, which can be used in preoperational planning or for surgical guiding during an intervention. Software framework which is introduced in this study is based on the Model-View-Controller (MVC) architectural pattern, and it uses 3D models of bones and plate implants developed by the application of the Method of Anatomical Features (MAF). The presented framework may be used for preoperative planning processes and for the production of personalized plate implants. The main idea of the research was to develop a novel integrated software framework which will provide improved personalized healthcare to the patient, and at the same time, provide the surgeon with more control over the patients treatment and recovery.

Customized anatomically adjusted plate for fixation of mandible internal fractures

Mandible internal fractures are a common injury because of the mandibles lack of structural support. For the treatment of such injuries various fixation elements are used. In order to improve quality of the orthodontists interventions anatomically correct and geometrically accurate customized implants are necessary. In this paper an example of accurate geometrical model of the customized plate implant for the fixation of mandible fracture is presented. For the creation of such model new method has been developed. This method is based on reverse engineering techniques applied on the CT scan of the specific patient mandible. With the application of this method it is possible to create geometrical model of the customized plate implant which geometry and topology conforms to the shape of the mandible of the specific patient. The side of the implant, which is in contact with a periosteum outer layer of the mandible, is fully aligned with the shape of the mandible outer surface near the fracture. The obtained model(s) can be used for production of plate implants, and/or for simulation of orthodontist interventions.

The artificial neural network based system for validation of thermocouples used in biomedicine

Machining operations are widely used in the orthopedic surgery. The temperature which occurs in the cutting zone, during the machining of the bones, may have many negative consequences in the postoperative period. Therefore, the measuring and the modeling of this parameter is a very important task. In this paper, the thermocouples are presented as a potential tool for the temperature measuring. The paper also deals with the system for validation of the thermocouples. The artificial neural network is used for modeling of the relationship between the electromotive force (as the thermocouple output) and the corresponding temperature. It is shown that the results of the modeling are in good correlation with the measured data.

The Modelling Approach of Data and Knowledge Bases of Expert Capp Systems

The paper presents a modelling approach of data and knowledge bases of the CAPP systems based on expert system technology. The model uses a hybrid modelling approach with heuristic and deterministic type of knowledge represented in an integrated knowledge base. If more then one rule can be fired, then its selection will be based upon the Certenity Factors (CF) that specify the priority of rules. The model presented in the paper has some generic features and could be used in other engineering applications with a relatively small modification. The proposed model is implemented in the CAPROT system for process planning of rotational mechanical parts.