Towards Sensing Information Systems

Recent advances in the field of pervasive computing, including the approaches and technologies related to Wireless Sensor Networks (WSN), Internet of Things (IoT) and Cyber Physical Systems (CPS) are changing the way we perceive computing capability. Although the scientific communities have already started to discuss about the visionary concepts that will exploit these advances, such as Sensing and Liquid Enterprise, the truly smart and interoperable CPS networks are still confined to the ‘valley of death’ - between prototyping and mass-production. In this position paper, we propose the concept of Sensing Information System, a novel paradigm that will facilitate the transformation of CPS to Cyber Physical Ecosystems - borderless technical environments in which the devices will become capable to sense, perceive, decide and act, based on the external, common behavioural and context models. A case study is used to demonstrating the use of Sensing Information Systems for extended clinical workflows

FOREWORD

Foreword to the thematic issue entitled:BIOMEDICAL ENGINEERING - ONE OF THE GREATEST ENGINEERING CHALLENGE

Analysis of correlations of multiple-performance characteristics for optimization of CO2 laser nitrogen cutting of AISI 304 stainless steel

The identification of laser cutting conditions for satisfying different requirements such as improving cut quality characteristics and material removal rate is of great importance. In this paper, an attempt has been made to develop mathematical models in order to relate laser cutting parameters such as the laser power, cutting speed, assist gas pressure and focus position, and cut quality characteristics such as the surface roughness, kerf width and width of heat affected zone (HAZ). A laser cutting experiment was planned as per Taguchi’s L27 orthogonal array with three levels for each of laser cutting parameters considered. 3 mm thick AISI 304 stainless steel was used as workpiece material. Mathematical models were developed using a single hidden layer artificial neural network (ANN) trained with the Levenberg– Marquardt algorithm. On the basis of the developed ANN models the effects of the laser cutting parameters on the cut quality characteristics were presented. It was observed that laser cutting parameters variously affect cut quality characteristics. Also, for the range of operating conditions considered in the experiment, laser cut quality operating diagrams were shown. From these operating diagrams one can see the values of cut quality characteristics that can be achieved and subsequently select laser cutting parameter values. Furthermore, the analysis includes correlations between cut quality characteristics and material removal rate. To this aim, six trade-off operating diagrams for improving multiple responses at the same time were given

FOREWORD

Editoria

ONTOLOGICAL FRAMEWORK FOR KNOWLEDGE MANAGEMENT IN ORTHOPEDIC SURGERY

Efficiency and effectiveness of orthopedic surgery can be achieved by enabling proper decision-making in a shortest period of time, based on complete and updated information on the status, type of fracture and fixators used for a particular fracture. In this way, the risk of possible complications caused by a late intervention can be reduced. In such circumstances, there exist critical needs for an effective and efficient knowledge management approach where different domain models are combined and formally interrelated, so that the decisions are based on the consistent and complete information. In this paper, ontologies are used to propose a framework for implementing such an approach in the domain of orthopedic surgery. The framework combines formal models of the generic products and supply chains for their manufacturing and delivery, anatomical elements, e.g. bones, types of their fractures and fixators – the medical products which are used in the fracture treatments. Then the possible uses of this framework for the purpose of knowledge management in orthopedic surgery are discussed in the context of the assumptions of development of Next Generation Enterprise Information Systems

Tyre Design and Optimization by Dedicated CAD Tyre Model

Structural optimization by Finite Elements (FE) is proved very effective in tyre design. For that purpose, major tyre manufacturers use in-house applications. An alternative solution, involving dedicated CAD tyre model (DCTM), is here proposed. DCTM concept permits to easily change the FE tyre models, concerning shape and structure, by moving a part of pre-processing from FE analysis to CAD. No special skills regarding CAD or FEA are required. For every new tyre design, only a new DCTM and a corresponding FE model must be built. All subsequent model changes are automatically performed by mapping and translation routines. To test this concept, DTCM models of an existing tyre were created and used within a pilot design study

REVERSE ENGINEERING OF THE HUMAN FIBULA BY USING METHOD OF ANATOMICAL FEATURES

This paper describes reverse engineering (RE) of human fibula, on right male bone, using the method of anatomical features (MAF) with the aim to obtain 3D surface model. The first step in the process of reverse engineering was CT scanning and digitalization of data. CT data were obtained with Toshiba MSCT scanner Aquillion 64 and saved in DICOM format. This data were subjected to further processing and imported in Computer Aided Design (CAD) program as STL file. The process continues in CAD program with identification and determination of Referential Geometrical Entities (RGEs) which are crucial for RE process. These RGEs are the basis for definition of axis and planes of intersection. Intersecting polygonal model of fibula bone on upper and lower extremities and the body with these planes gives as result set of curves, which were used for points determination on them. Through these points splines were pulled, and with loft function surface models of extremities and the body of fibula bone is built. Joining and merging of these models leaded to 3D shape model of fibula bone. Accuracy of the model is confirmed by conducting distance and deviation analysis. Model is suitable for rapid prototyping, reconstruction missing parts of fibula bone, orthopedic training and simulation

Različiti pristupi za kreiranje geometrijskih modela anatomske osi femura i tijela femura

In today\u27s medicine, especially in the field of orthopedic surgery, it is very important to use geometrically accurate and anatomically correct geometrical models of human bones for the pre-operative planning and implants creation. In order to create such models, two new methods for geometrical modeling were developed and presented in this paper. These methods enable creation of femur anatomical axis and femur shaft geometrical models, and they are: GCM (Gravity Center Method), and CPM (Curve Projection Method). Both methods enable creation of geometrical models which are based on data acquired from the medical imaging devices (CT, MRI, X-Ray). The basic difference between these two methods and all the others is in the manner of generating the points through which anatomical axis model (3D curve) passes or goes near. The applied methods are developed considering the natural shape and anatomical landmarks of the femur bone, as well as standard CAD techniques for geometrical modeling which are common in engineering.U današnjoj medicini, osobito u području ortopedske kirurgije vrlo je važno koristiti geometrijski točne i anatomski ispravne geometrijske modele ljudskih kostiju za pred-operativno planiranje i kreiranje implantata. Radi kreiranja takvih modela dvije nove metode geometrijskog modeliranja su razvijene i prezentirane u ovom radu. Ove metode omogućuju kreiranje geometrijskih modela anatomske osi femura i tijela femura i one su: GCM (eng. Gravity Center Method), i CPM (eng. Curve Projection Method). Obje metode omogućavaju kreiranje geometrijskih modela koji se temelje na podacima dobivenih od medicinskih uređaja (CT, MRI, X-Ray). Osnovna razlika između ove dvije metode u odnosu na sve ostale je u načinu generiranja točaka kroz koje anatomska os modela (3D krivulja) prolazi ili je u blizini. Primijenjene su tehnike koje su razvijene uzimajući u obzir prirodni oblik i anatomske značajke femura. kao i standardne CAD tehnike za geometrijsko modeliranje koje su uobičajene u inženjerstvu

Usporedba odziva modela pneumatika s detaljnim gaznim slojem i pojednostavljenog modela za analizu kotrljanja pneumatika u stacionarnom stanju

This paper deals with the level of detail that is necessary for representation of tread pattern in finite element tire models. Different methods for creation of tire tread mesh are systematized by two different criteria: the most common approaches and the finite element analysis type. Some of the representative approaches found in literature are given in more detail and their advantages and disadvantages discussed. An example from author’s experience, which describes the creation of finite element tire model with detailed tread for steady-state rolling analysis, is presented. The paper also brings a head-to-head comparison of the response of simplified and detailed tread tire models, subjected to a range of finite element analyses, from footprint analysis at static loading conditions to steady-state rolling cornering analysis.Ovaj rad se bavi razinom detalja koja je potrebna za prikaz šare gaznoga sloja u modela pneumatika namjenjenih analizi primjenom metode konačnih elemenata. Različite metode za izradu mreže konačnih elemenata su sistematizirane po dva različita kriterija: najčešćih pristupa i tipa analize primjenom metode konačnih elemenata. Neki od tipičnih pristupa koji se mogu naći u literaturi opisani su u više detalja i navedene su njihove prednosti i nedostaci. U članku je dat primjer iz iskustva autora, koji opisuje stvaranje modela pneumatika s detaljnim gaznim slojem za analizu kotrljanja u stacionarnom stanju. U radu je također prikazana izravna usporedba odziva pojednostavljenog modela pneumatika i modela s detaljnim gaznim slojem, podvrgnutih nizu analiza, od analize kontakta između tla i pneumatika pod statičkim uvjetima opterećenja do skretanja pri kotrljanju u stacionarnom stanju

Distal tibial pilon fractures (AO/OTA type B, and C) treated with the external skeletal and minimal internal fixation method

Background/Aim. Distal tibial pilon fractures include extra-articular fractures of the tibial metaphysis and the more severe intra-articular tibial pilon fractures. There is no universal method for treating distal tibial pilon fractures. These fractures are treated by means of open reduction, internal fixation (ORIF) and external skeletal fixation. The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to the use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management. The aim of this study was to estimate efficacy of distal tibial pilon fratures treatment using the external skeletal and minimal internal fixation method. Methods. We presented a series of 31 operated patients with tibial pilon fractures. The patients were operated on using the method of external skeletal fixation with a minimal internal fixation. According to the AO/OTA classification, 17 patients had type B fracture and 14 patients type C fractures. The rigid external skeletal fixation was transformed into a dynamic external skeletal fixation 6 weeks post-surgery. Results. This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60) years. The average follow-up was 21.86 (from 12 to 48) months. The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%. The mean to fracture union was 14 (range 12-20) weeks. There were 4 (12.19%) infections around the pins of the external skeletal fixator and one (3.22%) deep infections. The ankle joint arthrosis as a late complication appeared in 4 (12.90%) patients. All arthroses appeared in patients who had type C fractures. The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients. Conclusion. External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for treating all types of inta-articular pilon fractures. In fractures types B and C dynamic external skeletal fixation allows early mobility in the ankle joint. [Projekat Ministarstva nauke Republike Srbije, br. III41017