APPLICATION FEATURES OF FUZZY CONTROLLERS ON EXAMPLE OF DC MOTOR SPEED CONTROL

A prerequisite for the use of intelligent control methods, including algorithms of fuzzy logic, is increasing complexity in all industries, especially when parameters of technical systems while in operation vary in wide range. The paper provides comparative analysis of the basic types of common fuzzy direct action controllers on the example of speed control system in the DC motor drive. Design features of these types of fuzzy controllers are shown. Their comparison with traditional PI controller is carried out through the use of simulation, including the conditions of uncertainty expressed in changing of equivalent moment of inertia of the motor shaft. As a result, the conclusion about the feasibility of fuzzy PID-type controller application is made. The features of fuzzy controllers outlined in the paper can be summarized to more complex motor drive systems and to other non-linear systems that require the maintenance of any parameter within a given range

Tuning Pt characteristics on Pt/C catalyst for aqueous-phase reforming of biomass-derived oxygenates to bio-H-2

Pt/C catalysts with varied Pt sizes and distributions were investigated for aqueous-phase reforming (APR) of ethylene glycol (EG) to H2. APR experiments were performed on a continuous-flow fixed bed reactor with a catalyst loading of 1 g and EG feeding of 120 mL h−1 at 225 °C and 35 bar for 7 h. The fresh and used Pt/C catalysts were characterized by XRF, BET, CO chemisorption, TEM, XTEM, and XPS. Catalyst preparation protocols changed Pt characteristics on Pt/C catalysts, leading to a distinguishable H2 production. The rates for EG conversion and H2 production increased linearly with mean Pt size (3–11 nm), while having a volcano relationship with the mean size of agglomerated Pt particles (17–30 nm). Pt with concentrated Pt particles on surface of Pt/C catalysts was more preferable for APR of EG than the homogeneously distributed in catalysts. Optimal performance was obtained over a Pt/C-PR catalyst, which was prepared by precipitation method, showing a superb turnover frequency of 248 molH2 molPt−1 min−1 for H2 production from EG in APR. Besides, Pt/C catalysts also showed excellent stability. These results have shown the promise of Pt/C catalyst for APR of EG, which can be extended for bio-H2 production via APR of biomass-derived oxygenates in waste streams

Abnormal gut microbiota and impaired incretin effect as a cause of type 2 diabetes mellitus

It has now been established that the intestinal microbiota (CM) is one of the 11 links in the pathogenesis of type 2 diabetes mellitus (DM2). Th e fact is that when the composition of BM is disrupted and the concentration of its active metabolites changes, the processes of synthesis and secretion of incretin hormones are disrupted, the homeostasis of carbohydrates and fats in the body is disrupted, the processes of central regulation of appetite change, chronic infl ammation and insulin resistance of peripheral tissues develop. Th is review discusses possible ways of impairing the synthesis of incretin hormones and the incretin eff ect in patients with T2DM through the prism of BM and its active metabolites, and discusses possible ways of correcting the altered composition of BM with incretin drugs.A systematic literature search was carried out using the Scopus, PubMed, Web of Science databases

The first result of the neutrino magnetic moment measurement in the GEMMA experiment

The first result of the neutrino magnetic moment measurement at the Kalininskaya Nuclear Power Plant (KNPP) with the GEMMA spectrometer is presented. An antineutrino-electron scattering is investigated. A high-purity germanium detector of 1.5 kg placed 13.9 m away from the 3 GW reactor core is used in the spectrometer. The antineutrino flux is $2.73\times 10^{13} \nu_e / cm^2 / s$. The differential method is used to extract the $\nu$-e electromagnetic scattering events. The scattered electron spectra taken in 6200 and 2064 hours for the reactor ON and OFF periods are compared. The upper limit for the neutrino magnetic moment $\mu_\nu < 5.8\times 10^{-11}$ Bohr magnetons at 90{%} CL is derived from the data processing.Comment: 9 pages, 10 figures, 2 table

On the Complexity of Query Result Diversification

Query result diversification is a bi-criteria optimization problem for ranking query results. Given a database D, a query Q and a positive integer k, it is to find a set of k tuples from Q(D) such that the tuples are as relevant as possible to the query, and at the same time, as diverse as possible to each other. Subsets of Q(D) are ranked by an objective function defined in terms of relevance and diversity. Query result diversification has found a variety of applications in databases, information retrieval and operations research. This paper studies the complexity of result diversification for relational queries. We identify three problems in connection with query result diversification, to determine whether there exists a set of k tuples that is ranked above a bound with respect to relevance and diversity, to assess the rank of a given k-element set, and to count how many k-element sets are ranked above a given bound. We study these problems for a variety of query languages and for three objective functions. We establish the upper and lower bounds of these problems, all matching, for both combined complexity and data complexity. We also investigate several special settings of these problems, identifying tractable cases. 1

Bimodal Brightness Oscillations in Models of Young Binary Systems

We consider a model for the cyclic activity of young binary stars that accrete matter from the remnants of a protostellar cloud. If the orbit of such a binary system is inclined at a small angle to the line of sight, then the streams of matter and the density waves excited in the circumbinary disk can screen the primary component of the binary from the observer. To study these phenomena by the SPH (smoothed particle hydrodynamics) method, we have computed grids of hydrodynamic models for binary systems based on which we have constructed the light curves as a function of the orbital phase.The main emphasis is on investigating the properties of the brightness oscillations. Therefore, the model parameters were varied within the following ranges: the component mass ratio q = M2 : M1 = 0.2 - 0.5 and the eccentricity e = 0 - 0.7. The parameter that defined the binary viscosity was also varied. We adopted optical grain characteristics typical of circumstellar dust. Our computations have shown that bimodal oscillations are excited in binaries with eccentric orbits, provided that the binary components do not differ too much in mass. In this case, the ratios of the periods and amplitudes of the bimodal oscillations and their shape depend strongly on the inclination of the binary plane and its orientation relative to the observer. Our analysis shows that the computed light curves can be used in interpreting the cyclic activity of UX Ori stars.Comment: 14 pages, 5 figures, 1 tabl

Brightness Oscillations in Models of Young Binary Systems with Low-Mass Secondary Components

We consider a model for the cyclic brightness variations of a young star with a low-mass companion that accretes matter from the remnants of a protostellar cloud. At small inclinations of the binary orbit to the line of sight, the streams of matter and the density waves excited in the circumbinary disk can screen the primary component of the binary from the observer. To study these phenomena, we have computed grids of hydrodynamic models for binary systems by the SPH method based on which we have constructed the phase light curves as a function of the rotation angle of the apsidal line relative to the observer. The model parameters were varied within the following ranges: the component mass ratio q = 0.01-0.1 and the eccentricity e = 0-0.5. We adopted optical grain characteristics typical of circumstellar dust. Our computations have shown that the brightness oscillations with orbital phase can have a complex structure. The amplitudes and shapes of the light curves depend strongly on the inclination of the binary orbit and its orientation relative to the observer and on the accretion rate. The results of our computations are used to analyze the cyclic activity of UX Ori stars.Comment: 13 pages,8 figures, 1 tabl

The background in the neutrinoless double beta decay experiment GERDA

The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta decay of 76Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the Q-value of the decay, Q_bb. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around Q_bb. The main parameters needed for the neutrinoless double beta decay analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around Q_bb with a background index ranging from 17.6 to 23.8*10^{-3} counts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model are consistent. The observed number of events in this energy region is consistent with the background model. The background at Q-bb is dominated by close sources, mainly due to 42K, 214Bi, 228Th, 60Co and alpha emitting isotopes from the 226Ra decay chain. The individual fractions depend on the assumed locations of the contaminants. It is shown, that after removal of the known gamma peaks, the energy spectrum can be fitted in an energy range of 200 kev around Q_bb with a constant background. This gives a background index consistent with the full model and uncertainties of the same size

ASSOCIATION BETWEEN CLINICAL MANIFESTATIONS AND ULTRASONIC SIGNS OF INFLAMMATION IN PATIENTS WITH RHEUMATOID ARTHRITIS

Rheumatoid arthritis (RA) is a systemic autoimmune rheumatic disease characterized by chronic inflammation of the synovial membrane and a wide range of extra-articular (systemic) manifestations. The main goal of RA therapy is to achieve low disease activity or clinical remission. Power Doppler (PD) ultrasonography (USG) can significantly distinguish between active synovitis (hypervascularization of the synovial membrane) and inactive synovial proliferation.Objective: to investigate the association between the ultrasonic signs of active inflammation and the clinical and laboratory parameters of disease activity in patients with RA.Subjects and methods. The investigation included RA patients followed up at the V.A. Nasonova Research Institute of Rheumatology within the first Russian strategic study of pharmacotherapy for RA – REMARCA (Russian invEstigation of MethotrexAte and biologicals for eaRly aCtive Arthritis). A total of 105 RA patients (mean age 51 years), among whom 80% were rheumatoid factor (RF)-positive and 75% were anti-cyclic citrullinated peptide (ACCP)-positive, were examined. In all the patients, methotrexate (metoject, MEDAC, Germany) as the first diseasemodifying anti-rheumatic drug was subcutaneously injected in an initial dose of 10 mg/week with its rapid escalation up to 20–25 mg/week. Then the therapy was added by biologicals as the need arose. The clinical and laboratory parameters were analyzed immediately before and then 12, 24, 36, and 48 weeks following treatment. Therapeutic efficacy was evaluated using the European League Against Rheumatism (EULAR) criteria and activity indices (DAS28, CDAI, and SDAI). USG of eight articular areas (the wrist, second and third metacarpophalangeal, second and third proximal interphalangeal, second and fifth metatarsophalangeal articulations) in the hand and foot of the clinically dominant side was carried out in all the patients prior to treatment and at 12, 24, 36, and 48 weeks after its initiation. Semiquantitative gray-scale (GS) assessment and PD USG were performed according to the OMERACT criteria.Results and discussion. Weak correlations were found between USG parameters and DAS28, SDAI, and CDAI. After 48-week therapy, the signs of active synovitis were absent in 54 patients and persisted in 51, as evidenced by PD USG. The differences in clinical, laboratory, and ultrasonic parameters were analyzed in relation to USG evidence for active inflammation following 48 weeks of treatment. There were significant differences in GS and PD scores throughout the follow-up period; there were also differences in C-reactive protein levels at 12 and 48 weeks of therapy. No differences were found in clinical activity indices.Conclusion. The investigation provides support for the important role of USG in assessing the activity of synovitis in RA

Characterization of 30 76^{76}Ge enriched Broad Energy Ge detectors for GERDA Phase II

The GERmanium Detector Array (GERDA) is a low background experiment located at the Laboratori Nazionali del Gran Sasso in Italy, which searches for neutrinoless double beta decay of $^{76}$Ge into $^{76}$Se+2e$^-$. GERDA has been conceived in two phases. Phase II, which started in December 2015, features several novelties including 30 new Ge detectors. These were manufactured according to the Broad Energy Germanium (BEGe) detector design that has a better background discrimination capability and energy resolution compared to formerly widely-used types. Prior to their installation, the new BEGe detectors were mounted in vacuum cryostats and characterized in detail in the HADES underground laboratory in Belgium. This paper describes the properties and the overall performance of these detectors during operation in vacuum. The characterization campaign provided not only direct input for GERDA Phase II data collection and analyses, but also allowed to study detector phenomena, detector correlations as well as to test the strength of pulse shape simulation codes.Comment: 29 pages, 18 figure