Improving the knee prosthesis kinematics with the use of the evolutionary algorithm

A térdprotéziseknek számos követelménynek meg kell felelniük, amelyek a szilárdsági, funkcionális, gyárthatósági, tartóssági és kompatibilitási szempontok. A gyártóknak ezeket a – sokszor egymásnak ellentmondó – feltételeket kell kielégíteni. A fejlesztés alapja a megfelelő geometria kiválasztása, amelyben az eredeti térdgeometriát nem lehet alapul venni, mert olyan bonyolultságú, annyi elemből álló és olyan anyagtulajdonságú protézis nem gyártható. Ezért a protézisek a valós térdnél egyszerűbbek, a mozgást két egymáson elmozduló elemmel biztosítják.1 A megfelelő geometria kiválasztása kulcsfontosságú, mert a tibia mozgását ezen két elem felületével kell biztosítani. A mozgást ismertnek feltételezzük (mérhető), és keressük az ezt létrehozó felületeket. Az ilyen jellegű problémák megoldására jól alkalmazható az evolúciós algoritmus valamelyik típusa. A munkánk során kidolgoztunk egy eljárást, amely genetikus algoritmus segítségével a térdprotézisek, mint egyedek „virtuális tenyésztését” teszi lehetővé. A tenyésztést bármelyik tulajdonság fejlesztésének céljából elvégezhetjük, jelen tanulmányban az említett mozgásfüggvény ismeretéből indulunk ki.  DOI: 10.17489/biohun/2017/1/07The knee prostheses have to meet lots of requirements, which are: strength, function, manufacturability, durability and compatibility. The manufacturers have to meet with these often contradictory conditions. The basis for the development of knee prosthesis is the choice of the appropriate geometry. The original human knee geometry cannot be taken as a base for the prosthesis development because a prosthesis with so complexity, so many components and materials cannot be manufactured. Therefore the prostheses are simpler than the real knee joint. They can realize the movement with two on each other movable components.1 The movement of the tibia must be ensured by the two prosthesis components therefore it is really important to choose the right geometry. We are hypothesizing the motion (measurable) and we are looking for the surfaces that create it. For those tasks to solve one of the evolutional algorithm types is a good choice. During our work we elaborated a process that allows the „virtual breeding” of knee prostheses as individuals with the use of genetically algorithm. The breeding can be carried out for the development for either of the properties. In this study we are starting from the knowledge of the so called motion function

Introduction to 3d printing: techniques, materials and agricultural applications

The Production of complex products is easily possible with the help of additive manufacturing. By using additive manufacturing products may be mass-produced. Compared to traditional subtractive manufacturing, Additive manufacturing is advantageous in short design cycles, suitable for manufacturing complex structures, and high material utilization. Polymers and composites are frequently used in AM technologies, which have evolved into a variety of industrial and emerging applications. Among the many materials currently used in 3D printing are ceramics, metals, polymers, and concrete. ABS and PLA thermoplastics are the most often used materials for agricultural 3D printing since they are easy to print and relatively cheap. This article provides an overview of 3D printing technologies, materials, and applications in agriculture

Hydrodynamic modelling and analysis of a new-developed mobile refrigerated container

In this paper the hydrodynamic air flow relations in two adjustable compartment units of the mobile refrigerated container were examined. Analytical solution of the hydrodynamic equations describing the cooling air flow motion is not possible. We applied two possible methods for the solution: (1) – small scale test, (2) – approximate solution of the ordinary differential equations with finite elements simulation. The objective of the performed tests is to define the cooling air flow kinematical conditions, such as air velocity distribution in empty and fully loaded state, testing the shape of the air inlet profile and furthermore to determine the necessity of auxiliary ventilators adaptation. According to the performed test results a proposal to the final development of the cooling and ventilation elements has been made

Adatok a Baláta-tó algaflórájához

Halász (1943) és Uherkovich (1978) 177 faj előfordulását közölte a Baláta-tóból. 1991-ben, valamint 1995-1996-ban végzett vizsgálataink során további 137 taxon került elő, melyek közül számos faj egyúttal Magyarország flórájára nézve is új. A flóra különösen gazdag Desmidiales és Synurophyceae fajokban. A talált fajok egy része kizárólag savas vizekben, lápokon fordul elő, mások kevésbé specializáltak, sőt néhány alkalikus, hipertróf vizekből is előkerül. Mindezek alapján a Baláta-tó átmeneti lápnak minősíthető. Vizsgálataink megerősítik Boros (1924) századeleji megállapítását, amely szerint a Baláta-tó és a Rétyi Nyír (Erdély, Kovászna megye) között igen nagy a florisztuikai hasonlóság

Analysis and Comparison of Rapid Methods for the Determination of Ochratoxin A Levels in Organs and Body Fluids Obtained from Exposed Mice

Mycotoxins are bioaccumulative contaminants impacting animals and humans. The simultaneous detection of frequent active exposures and accumulated mycotoxin level (s) in exposed organisms would be the most ideal to enable appropriate actions. However, few methods are available for the purpose, and there is a demand for dedicated, sensitive, reliable, and practical assays. To demonstrate the issue, mice were exposed to a relevant agent Ochratoxin A (OTA), and accumulated OTA was measured by fine-tuned commercial assays. Quantitative high-performance liquid chromatography with fluorescence detection, enzyme-linked immunosorbent assay, and flow cytometry assays have been developed/modified using reagents available as commercial products when appropriate. Assays were performed on excised samples, and results were compared. Accumulated OTA could be detected and quantified; positive correlations (between applied doses of exposure and accumulated OTA levels and the results from assays) were found. Dedicated assays could be developed, which provided comparable results. The presence and accumulation of OTA following even a short exposure could be quantitatively detected. The assays performed similarly, but HPLC had the greatest sensitivity. Blood contained higher levels of OTA than liver and kidney. We demonstrate that specific but flexible and practical assays should be used for specific/local purposes, to measure the exposure itself and accumulation in blood or organs