An application of mu-synthesis for control of a small air vehicle and simulation results

This paper discusses a nonlinear robust control design procedure to micro air vehicle that combines the singular value (µ) and µ-synthesis technique, which overcomes structured uncertainty of the control plant and is valid over the entire flight envelope. The uncertainty model consists with multiplicative plug-in dynamics disturbances and parametric uncertainty. The uncertainty is conducted with the aircraft aerodynamics characteristics and parameters. These uncertainties are bounded in size based on wind tunnel experiments, flight test and analytical calculations. Furthermore, these investigations allow us to obtain the linearized model of the aircraft called here nominal model

External Support Structures in Fused Deposition Modeling 3D Printing

3D Printing, sometimes also referred to as Additive Manufacturing, is a technology that has garnered a lot of attention in the past several years. While the technology has attracted a significant community of hobbyists, the benefits of the technology have also been recognized in manufacturing. While there are many different types of 3D Printing techniques, the most common type is Fused Deposition Modeling (FDM), mainly due to its relatively low cost compared to other types. However, the technique also present a significant limitation: it tends to struggle with models that have overhanging parts. When a layer is extruded by an FDM printer, it will only stay in place if there is something for it to rest on from below. Overwise, it will fall onto the print bed due to gravity. In a lot of cases, the most feasible way to solve the problem of overhangs is through printing external support structures. The process of designing and adding support structures to 3D models can be very time consuming, so many developers have attempted to write programs that generate these structures automatically. The process of generating external support structures presents several challenges, attempting to create supports that are stable, but also use the least material and take the least time to print. The purpose of this paper is to present the challenges that come with designing these programs, and the methods used in the programs to overcome those challenges

The oxidation of ascorbic acid in the presence of copper

I.The oxidation of ascorbic acid.by molecular oxygen with copper as catalyst is inhibited by sodium chloride 2.This type of catalysis and also inhibition takes place also in absolute alcohol. 3. The inhibition by NaCl is parallel to Cuᶦᶦ-Cuᶦ transformation. 4.Copper catalyses the decomposition of hydrogen peroxide ,this reaction is not inhibited by NaCl. 5.NaCl shows an activating influence on the decomposition of hydrogen peroxide. 6.Copper catalyses the oxidation of methyl red and tyrosine by H₂O₂.NaCl activates this catalysis. 7.The decomposition of H₂O₂ in the presence of copper is inhibited by the presence of substrate suitable for oxidation by peroxidase mexhanmsm. 8.The oxidation of acsorbic acid by H₂O₂ is catalysed by copper, this reaction is inhibited by NaCl. 9.Tyrosine inhibits the oxidation of ascorbic acid b 02 and H202 with copper as catalyst.On the other hand the products of tyrosine oxidation oxidaize ascorbic acid. 10. In the presence of tyrosine the influence of NaCl on ascorbic acid oxidation is reversed - activation instead of inhibiting.. 11. The participation of quinones in acsorbic acid oxidation in inorganic systems has been examined. 12.In rotato the quinones formed during the oxidation of tyrosine are the chief agent resÿonsible for the oxidation of ascorbic acid. 13.The influence of ascorbic acid on the oxidation o tyrosine has been examined I4. Sodium chloride, probably indirectly, activates the type of ascorbic acid oxidation. 15. Ascorbic acid oxidase is not inhibited by NaCl. 16. Proteins inhibit the oxidation of ascorbic acid and diminish the inhibitory influence of NaCl on this process

Realization of coordination technology of hierarchical systems in design of active magnetic bearings system

A cybernetic technology of mechatronic design of active magnetic bearings systems (AMB) originated from theory of systems is suggested in the paper. Traditional models of artificial intelligence and mathematics do not allow describing mechatronic systems being designed on all its levels in one common formal basis. They do not describe the systems structure (the set of dynamic subsystems with their interactions), their control units, and do not treat them as dynamic objects operating in some environment. They do not describe the environment structure either. Therefore, the coordination technology of hierarchical systems has been chosen as a theoretical means for realization of design and control. The theoretical basis of the given coordination technology is briefly considered. An example of technology realization in conceptual and detailed design of AMB system is also presented

Vibrating a small plate vortex generator to improve control robustness of a micro aerial delta wing vehicle

In the work, vortex generators as a small vibrating plates adjusted to a delta wing surface are used for boundary layer control (BLC). The vortex generators applied to produce aircraft moments and aerodynamic forces are proposed and tested. The BLC for delta wing micro aircraft is calculated numerically by using fluid-structure interactions. The Navier-Stokes equations and Shear Stress Transport (SST) model were used for numerical calculations. The flexible oscillating small plates driven by controlled piezo stacks and their influence on the air flow in the delta boundary layer are investigated. The amplitude of the piezo stack vortex generator and frequency measurements are presented

Bibliotekarz systemowy – kto to w ogóle jest?

The author of the article presents his nine-year experience in implementing library systems. Today, a generation of library computerization pioneers in Poland is passing away. Their activity enabled relatively cost-effective set-up of a computerized workplace. However, due to the limited resources, some of the installations implemented were fairly unusual, and their simple replacement by integrated library systems is difficult or causes resistance. The role of the systems librarian is to understand and convince others that the library has to change its work organization in order to successfully use the currently produced systems. The systems librarian should also participate in the data transfer process as well as remove inconsistencies and increase standardization. The role of the systems librarian requires full-time employment in the library.Autor artykułu przedstawia swoje dziewięcioletnie doświadczenia przy wdrażaniu systemów bibliotecznych. Dziś odchodzi już pokolenie pionierów komputeryzacji bibliotek w Polsce. Ich działalność pozwoliła relatywnie niewysokim kosztem zbudować skomputeryzowane środowisko pracy. Jednak ograniczone środki spowodowały, że wdrożone instalacje są niejednokrotnie bardzo specyficzne i ich próba zastąpienia przez systemy zintegrowane natrafia na szereg trudności lub wręcz na opór. Rolą bibliotekarza systemowego jest zrozumienie, że biblioteka musi zmienić swoją organizację pracy, by wykorzystać obecnie produkowane systemy optymalnie, i przekonanie o tym innych. Powinien też uczestniczyć w procesie transferu danych, a przede wszystkim zadbać o usuwanie niespójności i standaryzację. Rola bibliotekarza systemowego wymaga pełnego etatu w bibliotece

Body fat MRS

The increasing levels of obesity, and its associated comorbidities, have prompted a reassessment of the techniques used for assessing body fat, including content, distribution, and composition. Magnetic resonance spectroscopy (MRS) is one among the many invaluable in vivo tools available today to evaluate the role of body fat in health and disease. However, although MRS has become a powerful technique for assessing ectopic fat in vivo, it has had limited use in other areas of research associated with body fat. MRS has found some success as a fast method to determine whole body adiposity in rodent models of disease, as well as a noninvasive method of obtaining an index of the overall composition of body fat in human subjects. Its more significant use has been in the understanding of bone marrow fat content, where important advances have been made, especially in longitudinal studies. In conclusion, in the area of body fat, MRS continues to be an adjunct technique to more precise and versatile MRI methods

LMS PATRON dla wymagających i odpowiedzialnych

The article presents the PATRON library management system intended for demanding libraries, a system for the 21st century. The system developers indicate some significant software features including on the one hand responsibility, flexibility, independence and on the other hand support as well as continuous development and 25 years long expertise.Artykuł przedstawia system biblioteczny PATRON dedykowany bibliotekom wymagającym, system na miarę XXI w. Twórcy systemu podkreślają istotne cechy oprogramowania, do których należą m.in. odpowiedzialność, elastyczność, samodzielność z jednej strony i wsparcie z drugiej strony, ciągły rozwój i 25-letnie doświadczenie

PLC-BASED DISCRETE FRACTIONAL-ORDER CONTROL DESIGN FOR AN INDUSTRIAL-ORIENTED WATER TANK VOLUME SYSTEM WITH INPUT DELAY

We present PLC-based fractional-order controller design for an industrial -oriented water tank volume control application. The system comprises input delay which is a typified characteristic in such industrial process control applications. The particular contribution of this work is on discrete fractional-order PID implementation via PLC and its application to the aforementioned realistic water tank test bed. Stability and robustness properties of fractional-order discrete PID feedback-loops for different approximation methods and orders are also shown. Fractional-order controllers are obtained for a variety of stability margin choices, and benefits of the non-integer-order controllers compared to the integer-order PID control are illustrated via simulation and experimental runs on a realistic test-bed

Vibrating a small plate vortex generator to improve control robustness of a micro aerial delta wing vehicle

In the work, vortex generators as a small vibrating plates adjusted to a delta wing surface are used for boundary layer control (BLC). The vortex generators applied to produce aircraft moments and aerodynamic forces are proposed and tested. The BLC for delta wing micro aircraft is calculated numerically by using fluid-structure interactions. The Navier-Stokes equations and Shear Stress Transport (SST) model were used for numerical calculations. The flexible oscillating small plates driven by controlled piezo stacks and their influence on the air flow in the delta boundary layer are investigated. The amplitude of the piezo stack vortex generator and frequency measurements are presented