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High-efficient isolated DC/DC converters with a high-efficiency synchronous reluctance generator (SRG) are the ultimate solutions in DC microgrid systems. The design and modeling of isolated DC/DC converters with the performance of SRG are carried out. On the generator side, reactive and active powers are used as pulse width modulation (PWM) control variables. Further, the flux estimator is used. Three-phase PWM rectifier is used by applying space vector modulation (SVM) with a constant switching frequency for direct power control. Further, the paper also includes the experimental validation of the results. The paper also proposes that highly efficient power converters and synchronous reluctance generators are required to achieve high performance for hybrid renewable energy systems applications.

Object: This study aims to identify differentially expressed genes (DEGs) between high-risk and non-high-risk groups in neuroblastoma (NB), construct a prognostic model, and establish a risk score formula. Materials and methods: The NB dataset GSE49710 (n = 498) from the GEO database served as the training cohort to select DEGs between high-risk and non-high-risk NB groups. Cellular senescence-related genes were obtained from the Aging Atlas database. Intersection genes from both datasets were identified as key genes of cellular senescence-related genes (SRGs). A prognostic model was constructed using Univariate Cox regression analysis and the Lasso algorithm with SRGs. Validation was performed using the E-MTAB-8248 cohort (n = 223). The expression levels of AURKA and CENPA were evaluated via RT-qPCR in two clinical NB sample groups. Results: Eight SRGs were identified, and a prognostic model comprising five genes related to cellular senescence was constructed. AURKA and CENPA showed significant expression in clinical samples and were closely associated with cellular senescence. Conclusion: The prognostic model consisted with five cellular senescence related genes effectively predicts the prognosis of NB patients. AURKA and CENPA represent promising targets in NB for predicting cellular senescence, offering potential insights for NB therapy. [ABSTRACT FROM AUTHOR]

Although a switched reluctance generator (SRG) is not the mainstream wind generator, it possesses the application potential and is worth developing for its many structural merits and high developed power ability. This paper presents a wind SRG-based bipolar DC microgrid having grid-connected and plug-in energy supporting functions. First, a surface-mounted permanent magnet synchronous motor (SPMSM)-driven wind turbine emulator (WTE) is established. Next, the wind SRG with an asymmetric bridge converter is developed. Good generating characteristics are obtained through proper designs of power circuit, commutation mechanism, external excitation source, voltage and current controllers. Third, a DC/DC boost interface converter and a bipolar voltage balancer are constructed to establish the 500 V microgrid bipolar DC-bus. To preserve the microgrid power supplying quality, a battery energy storage system (BESS) with bidirectional DC/DC interface converter is equipped. A dump load leg is added across the bus to limit the DC-bus voltage under energy surplus condition. In load side, a three-phase bidirectional load inverter is developed, which can be operated as a single-phase three-wire (1P3W) inverter or a three-phase three-wire (3P3W) inverter. Good sinusoidal voltage waveform and regulation characteristics are obtained using the proportional-resonant (PR) control. The microgrid to load and microgrid to grid operations are conductible. Finally, to further improve the powering reliability of microgrid, a three-phase T-type Vienna switch-mode rectifier (SMR) based plug-in energy supporting scheme is developed. When the microgrid energy shortage occurs, the possible harvested energy can be used to supply the microgrid. [ABSTRACT FROM AUTHOR]

The four completed six-month sky surveys with the eROSITA telescope onboard the SRG orbital observatory allow tidal disruption events (TDEs) in galactic nuclei to be searched for by their X-ray variability. In this case, variable active galactic nuclei (AGNs) are detected in much larger quantities, for the elimination of which fairly stringent criteria have to be used. Some TDEs can be missed or misclassified as probable AGNs. Optical spectroscopy needs to be performed for the final identification of TDEs among the extragalactic SRG/eROSITA transients. We consider a set of criteria by which TDEs can be distinguished from AGNs based on optical spectra and photometric information. In particular, we propose to use the ratio of the X-ray luminosity to the [O III] 5007 Å luminosity. To test the proposed method, we consider a sample of 15 extragalactic SRG/eROSITA transients whose X-ray flux changed by more than a factor of 7 between two adjacent surveys. Spectra have been taken for all these objects with Russian optical telescopes: RTT-150, AZT-33IK, RC2500, and BTA. We have managed to reveal five new and one previously known TDEs and to classify seven sources as AGNs. The nature of two more transients remains in question. The proposed method will help to set priorities to obtain a maximally complete and reliable sample of TDEs in the SRG/eROSITA survey. [ABSTRACT FROM AUTHOR]

Use of fabric-reinforced cementitious matrices (FRCM) is a very efficient strengthening solution for improving the structural behavior of existing masonry elements. FRCM are capable of improving the load-bearing capacity of masonry panels, at the same time providing more ductile behavior. However, the mechanical performances of these materials could be significantly affected by environmental conditions, such as exposure to thermal variations. This aspect should be properly assessed by guidelines and standards devoted to the design of strengthening interventions. Within this framework, the objective of the present research was to evaluate the effect of a temperature increase on the tensile behavior of various FRCM systems, composed of steel, basalt, or aramid-glass fibers and lime-based or cement-based mortar matrices. Tensile tests were performed for each system under different thermal conditioning protocols, comprising different target temperatures, exposure periods, test conditions, and adopted heating sources. The test results showed that the effect of temperature is more evident in the first phases of the tensile tests, that is, during the uncracked phase and the mortar matrix cracking phase, whereas it is less significant in the final phase, which was more related to fiber behavior. Comparisons between the different thermal conditioning procedures are critically discussed within the paper and, in light of the results obtained, recommendations are included to optimize the testing procedures for future research and qualification procedures. [ABSTRACT FROM AUTHOR]

In this paper, the influence of the strengthening configuration on the structural response of U-wrapped SRG (Steel-Reinforced Grout) shear-strengthened reinforced concrete beams was analyzed both experimentally and theoretically. The parameters varied were the ratio sf/wf, sf being the distance between two consecutive U-shaped strips and wf the width of the strips, and the number of steel fabric layers (one and two). Two series of real-scale beams, eleven beams in total with one un-strengthened and ten strengthened, were tested up to failure (the results obtained in the first series of tests were reported in a previously published paper). The obtained results highlighted that the debonding phenomena, which occurred for all the examined strengthening configurations, strongly affected the shear capacity of strengthened beams. An analytical model found based on the "effective strain" of the SRG strips was developed to predict the shear capacity of SRG shear-strengthened reinforced concrete beams. Two analytical relationships were proposed to evaluate the "effective strain" of the SRG strips: The first one was based on a statistical analysis of results obtained by tests on FRCM (Fabric-Reinforced Cementitious Mortar) and SRG shear-strengthened reinforced concrete beams, while the second was developed through the results of single lap direct shear tests performed on SRG-to-concrete joints. The effectiveness of the proposed analytical methods was evaluated through the comparison of their predictions and available experimental results. [ABSTRACT FROM AUTHOR]

We present a probabilistic model built for the optical cross-match between the SRG/eROSITA X-ray sources and photometric data from the DESI Legacy Imaging Surveys. The model relies both on positional and photometric information on optical objects nearby X-ray sources and allows performing selection with precision and recall (for erg s cm ). With this model, we calibrated positional error of the SRG/eROSITA sources detected in the Lockman Hole: . The model will become a part of the SRGz system for data analysis of the X-ray data obtained from the all-sky SRG/eROSITA survey. [ABSTRACT FROM AUTHOR]

We discuss the results of our spectroscopy for 17 candidates for distant quasars selected by the SRGz classification system based on data from the first and second sky surveys with the eROSITA telescope onboard the SRG X-ray observatory. Most of the quasar candidates were selected within the DaLeQo observing program, whose goal is a search for the most X-ray luminous quasars with luminosities erg s at redshifts . Our spectroscopic observations were carried out at the 6-m BTA telescope with the SCORPIO-2 spectrograph. We have managed to confirm eight new X-ray quasars at , including the quasar SRGe J020142.8-015347 at . Owing to the large diameter of the BTA mirror and the high quantum efficiency of the SCORPIO-2 spectrograph in the range 6000–9000 Å, we have managed to measure the С IV (1549 Å) line parameters and to estimate the supermassive black hole masses and accretion rates for seven quasars. [ABSTRACT FROM AUTHOR]

Based on observations with the transient double-beam spectrograph (TDS) at the 2.5-m telescope of the Caucasus Mountain Observatory of SAI MSU, we have determined the redshifts for 15 new quasars detected in X-rays by the eROSITA telescope of the SRG orbital observatory during the first three all-sky surveys. The redshifts of the sources lie in the range 0.5–4.156. We have estimated the masses of the central supermassive black holes and the bolometric luminosities for eight quasars from the width of the C IV 1549 Å emission line and the continuum flux at 1350 Å. For these objects we have also estimated the ratio of the X-ray luminosity to the Eddington limit to be a few percent. At the same time, the bolometric-to-Eddington luminosity ratio for them has turned out to be in a fairly narrow range, 30–40 . A large ratio points to an active growth of the mass of the central black holes in these objects. [ABSTRACT FROM AUTHOR]

This article presents the design and operation of a deflection type double stator switched reluctance generator (DDSRG) for wind turbine applications. The DDSRG can generate electricity with high efficiency according to the different wind directions. A deflectable SRG model is proposed to achieve the above requirements, which can deflect in space with different wind directions. First, this article introduces the special structure of the DDSRG. And the operating principle of DDSRG with special structure is explained. At the same time, the mathematical model of the external generator is built as an example. The voltage characteristics of DDSRG under different wind conditions such as directions, wind speeds, and deflection angles are studied. The comparison between the analytical method and the finite element method verifies the accuracy of the theory. Finally, the proposed DDSRG is tested to verify its power generation characteristics.

ABSTRAK Dewasa ini teknologi energi terbarukan biasanya menggunakan mesin listrik sinkron Alternating Current (AC) pada pembangkit listrik tenaga angin. Generator listrik sinkron AC menggunakan brush pada proses eksitasi yang membutuhkan perawatan berkala sehingga rumit jika diaplikasikan pada Pembangkit Listrik Tenaga Angin. Pada penelitian ini generator akan menggunakan mesin Switched Reluctance yang dioperasikan sebagai Switched Reluctance Generator (SRG). Untuk menghasilkan keluaran arus yang optimal, SRG akan dioperasikan dengan mengatur sudut penyalaan fasa menggunakan metode single pulse. Metode pensakelaran ini diatur oleh input capture fasilitas mikrokontrol dsPIC 30F4012. Penelitian ini telah diverifikasi dengan simulasi Simulink MATLAB dan pengujian alat. Hasil pengujian optimal dibuktikan pada sudut penyalaan θon = 40 derajat dan θoff = 170 derajat menghasilkan arus discharging sebesar 7.6 A dengan kecepatan 1647.1 RPM ditandai dengan bentuk gelombang arus yang ideal. Hasil arus discharging yang optimal dapat meningkatkan kinerja SRG, sehingga metode ini dapat diaplikasikan pada pembangkit listrik tenaga angin. Kata kunci: SRG, dsPIC30F4012, sudut penyalaan, single pulse ABSTRACT Nowadays, renewable energy technology usually uses AC synchronous electric machines in wind power. AC synchronous generator uses a brush in the excitation process, which requires periodic maintenance so it is complicated if applied to wind power. In this research, the generator will use a Switched Reluctance machine that operated as a SRG. To produce an optimal current, the SRG will be operated by adjusting the ignition angle using the single pulse method. This method is controlled by input capture of the microcontroller dsPIC 30F4012. This research has been verified by simulating Simulink MATLAB and testing device. The optimal test results are proven at the ignition angle θon = 40 degree and θoff = 170 degree produces a discharging current of 7.6 A with a speed of 1647.1 RPM characterized by the ideal current waveform. The optimal discharging current results can improve the performance of the SRG, so this method can be applied to wind power. Keywords: SRG, dsPIC30F4012, the ignition angle, single pulse

This paper presented an improved switching transient model of silicon carbide (SiC)-based asymmetric H-bridge (AHB) power converter for a switched reluctance generator (SRG), which takes the nonlinear phase inductance of the SRG into consideration. First, a systematic mathematic derivation is carried out and the switching transient model is established. Second, the impact of the nonlinear phase inductance of the SRG on switching transients is verified by PSpice & Simulink co-simulations. Third, a power loss model is established by the transient model through PSpice & Simulink co-simulations. The model is conducted to indicate the power loss characteristics of the SiC-based AHB power converter. Simulation results indicate that the nonlinear phase inductance of the SRG is able to accelerate the switching speed of SiC-MOSFETs, and that the SiC converter is advantageous in terms of power loss. Experimental results illustrate that the established power loss model experiences high accuracy. In addition, SiC devices are able to strengthen the power density and efficiency of a converter while reducing its heat dissipation requirements. [ABSTRACT FROM AUTHOR]

We assess tensile performance of Steel Reinforced Grout (SRG) and Fabric Reinforced Cementitious Matrix/Textile Reinforced Mortar, upon exposure to aggressive environments. Galvanized and brass-coated Ultra High Tensile Strength Steel fabrics are considered for SRG, while carbon, AR-glass, basalt and PBO fabrics are investigated for TRM, in a common cement mortar. Exposure to the aggressive environments is realized by specimen immersion for 1000 h (41.6 days) at controlled temperature in distilled water as well as alkaline, saline and acid solutions. Mechanical performance of rectangular 1-ply coupons is assessed in uni-axial traction: Ultimate strength and elongation, dissipated energy at failure and environmental conversion factors for design values are calculated and compared. It is found that significant performance difference exists in dependence of the aggressive environment under consideration. As a result, careful selection of the reinforcing fabric leads to substantial advantage in terms of durability, that should be capitalized upon at the design stage. A simple material selection matrix is presented which suggests the best reinforcing textile/aggressive environment combination for design purposes. [ABSTRACT FROM AUTHOR]

Results of the spectroscopic observations at the 1.5-m Russian–Turkish telescope for another group of 12 X-ray sources discovered by the eROSITA telescope onboard the SRG space observatory and identified by the SRGz machine learning system as candidates for distant X-ray quasars are presented. Ten objects have been confirmed as quasars at redshifts and two sources have turned out to be active galactic nuclei (AGNs) at and . [ABSTRACT FROM AUTHOR]

Composite materials for strengthening existing structural members represent a valid alternative to the traditional strengthening techniques. In particular, Fabric Reinforced Cementitious Matrix (FRCM) composites have been successfully employed to strengthen existing reinforced concrete and masonry structures.Among the different FRCM composites available on the market, the attention of the authors was recently focalized on systems composed of high tensile strength steel cords embedded in a cementitious matrix (systems also well known as Steel Reinforced Grout, SRG).The main failure mechanism of FRCM is represented by the debonding at the matrix-fiber interface. Therefore, the study of the bond behavior of FRCM composites is a key topic to develop reliable design procedures. In this paper, the applicability of different existing bond-slip interface models for FRP-concrete interface to SRG system is studied. The different parameters characterizing the models are calibrated by using an experimental database available by the authors and including results of direct single-lap shear tests on concrete prisms bonded to SRG strips. All the models are calibrated using a classical technique which minimizes the difference between the measured and computed interfacial shear stress values at different slip levels. The results indicate that all the models predict relatively well the slope of the ascending branch of the shear stress-slip curve, but they give substantially different descending branch profiles.The calibrated models are, then, compared with some other laws proposed in the literature for PBO and basalt FRCM systems; some of them are also implemented within a numerical procedure developed by the authors for the estimation of both the maximum axial stress at debonding and the corresponding effective bonded length of the SRG strip. The comparison with the experimental data has allowed for verifying the accuracy of the calibrated bond-slip models.

In this paper, the influence of the strengthening configuration on the structural response of U-wrapped SRG (Steel-Reinforced Grout) shear-strengthened reinforced concrete beams was analyzed both experimentally and theoretically. The parameters varied were the ratio sf/wf, sf being the distance between two consecutive U-shaped strips and wf the width of the strips, and the number of steel fabric layers (one and two). Two series of real-scale beams, eleven beams in total with one un-strengthened and ten strengthened, were tested up to failure (the results obtained in the first series of tests were reported in a previously published paper). The obtained results highlighted that the debonding phenomena, which occurred for all the examined strengthening configurations, strongly affected the shear capacity of strengthened beams. An analytical model found based on the “effective strain” of the SRG strips was developed to predict the shear capacity of SRG shear-strengthened reinforced concrete beams. Two analytical relationships were proposed to evaluate the “effective strain” of the SRG strips: The first one was based on a statistical analysis of results obtained by tests on FRCM (Fabric-Reinforced Cementitious Mortar) and SRG shear-strengthened reinforced concrete beams, while the second was developed through the results of single lap direct shear tests performed on SRG-to-concrete joints. The effectiveness of the proposed analytical methods was evaluated through the comparison of their predictions and available experimental results.

The incorporation of azobenzene chromophores into polymer systems gives rise to a number of unique effects under UV and visible light irradiation. The light-driven isomerization of the azobenzene element acts as a light-to-mechanical energy converter, translating the nanoscopic structural movement of the isomerization azobenzene into macroscopic topographic film modulation in the form of surface relief. This review focuses on the study of reversible changes in shape in various systems incorporating azobenzene, including large-scale superficial photo-patterned glassy materials, light-driven reshaping of tridimensional superficial azo-textures and contractions of stimuli-responsive liquid crystalline networks (LCNs). Further, promising applications of azo systems are investigated as smart biointerfaces able to mimic time-varying biological systems. [ABSTRACT FROM AUTHOR]

In the paper, the bond between a composite strengthening system consisting of steel textiles embedded into an inorganic matrix (steel reinforced grout, SRG) and the concrete substrate, is investigated. An experimental investigation was carried out on medium density SRG specimens; direct shear tests were conducted on 20 specimens to analyze the effect of the bond length, and the age of the composite strip on the SRG-to-concrete bond behavior. In particular, the tests were conducted considering five bond length (100, 200, 250, 330, and 450 mm), and the composite strip’s age 14th, 21st, and 28th day after the bonding. Test results in the form of peak load, failure modes and, bond-slip diagrams were presented and discussed. A finite element model developed through commercial software to replicate the behavior of SRG strips, is also proposed. The effectiveness of the proposed numerical model was validated by the comparison between its predictions and experimental results. [ABSTRACT FROM AUTHOR]

Recent temporal action proposal generation approaches have suggested integrating segment- and snippet score-based methodologies to produce proposals with high recall and accurate boundaries. In this paper, different from such a hybrid strategy, we focus on the potential of the snippet score-based approach. Specifically, we propose a new snippet score-based method, named Snippet Relatedness-based Generator (SRG), with a novel concept of “snippet relatedness”. Snippet relatedness represents which snippets are related to a specific action instance. To effectively learn this snippet relatedness, we present “pyramid non-local operations” for locally and globally capturing long-range dependencies among snippets. By employing these components, SRG first produces a 2D relatedness score map that enables the generation of various temporal intervals reliably covering most action instances with high overlap. Then, SRG evaluates the action confidence scores of these temporal intervals and refines their boundaries to obtain temporal action proposals. On THUMOS-14 and ActivityNet-1.3 datasets, SRG outperforms state-of-the-art methods for temporal action proposal generation. Furthermore, compared to competing proposal generators, SRG leads to significant improvements in temporal action detection. [ABSTRACT FROM AUTHOR]

The use of composite materials to strengthen masonry structures has become common practice within the civil engineering community. Steel-reinforced grout (SRG), which comprises high-strength steel fibers embedded in a mortar matrix, is part of the family of the fiber-reinforced cementitious matrix (FRCM) composites that represent a suitable alternative to fiber-reinforced polymer (FRP) composites for strengthening existing structures. Although studies on FRCMs have already reached a certain level of maturity, some key issues remain open, such as the role of matrix type and layout, substrate properties, and test rate. This paper focuses on some of these issues. The results of single-lap direct shear tests on masonry blocks strengthened with SRGs are presented to analyze the bond behavior between the composite material and the substrate. Four aspects are considered: (1) the change in the width of the SRG mortar matrix while keeping the width of the fiber sheet fixed; (2) the type of mortar used for the SRG; (3) the influence of the test rate, and (4) the type of substrate (i.e., concrete vs. masonry). The results obtained indicate the active role of the matrix layout and the importance of the test rate, encouraging further investigations to clarify these aspects. [ABSTRACT FROM AUTHOR]

Results of the first spectroscopic observations at the 1.5-m Russian–Turkish telescope for the X-ray sources discovered by the eROSITA telescope onboard the SRG space observatory and identified by the SRGz machine learning system as candidates for distant X-ray quasars are presented. Seven objects have been confirmed as quasars at redshifts and two sources, which were included in the program of optical observations aimed at testing and adjusting SRGz and had a significant uncertainty in the photometric redshift, have turned out to be Seyfert galaxies at . [ABSTRACT FROM AUTHOR]

This paper presents a proportional plus resonant (P+RES) controller applied to the control of generated power from the switched reluctance generator (SRG). The P+RES controller is used to reject any frequencies outside the resonant point, where its gain is infinite. The controller was implemented on digital signal processor (TMS320F2835), and the experimental results show that the proposal can be a good alternative for SRG's power control once, in addition to other benefits, they provide power ripple reduction. [ABSTRACT FROM AUTHOR]

During a deep extragalactic Lockman Hole sky survey with an area of 18.5 sq. deg, which was conducted when the SRG observatory was flying to the Lagrange point L2, the eROSITA telescope detected X-ray sources. These objects were then provisionally identified and classified using the publicly accessible data of optical and infrared sky surveys by the SRGz machine learning system developed for this purpose at the Space Research Institute of the Russian Academy of Sciences. As a result, a number of new candidates for distant quasars () have been selected. The spectroscopic observations of the first two candidates from this list carried out with the 1.6-m AZT-33IK telescope of the Sayan Solar Observatory have confirmed that these objects are actually distant quasars at redshifts 3.878 and 4.116 and are characterized by a high X-ray luminosity erg s (2–10 keV). The results obtained allow one to count on the detection of a large number of distant quasars during a four-year all-sky survey of the SRG observatory begun in December 2019. [ABSTRACT FROM AUTHOR]

• Nine shear critical RC beams where strengthened using SRG jacketing. • The effectiveness of U- and fully-wrapped SRG jackets was investigated. • Strength and deformation capacity increased up to 160% and 450%, respectively. • Digital Image Correlation confirmed the effectiveness of SRG jacketing. • Expressions are proposed for estimating the effective strain of the SRG jacket. This paper investigates the effectiveness of Steel-Reinforced Grout (SRG) jackets to strengthen shear critical reinforced concrete (RC) beams. Eleven RC beams were tested in three-point bending. Key parameters of investigation were the strengthening configuration (U- and fully-wrapped jackets), the density of the fabric (1.57 and 4.72 cords/cm) and the number of the strengthening layers (one and two). The test results demonstrated the efficiency of SRG jacketing in increasing both strength (up to 160%) and deformation capacity (up to 450%) of the shear critical beams. Expressions are proposed for estimating the effective strain of the SRG jacket. [ABSTRACT FROM AUTHOR]

The breast cancer is absolutely life intimidating and dreadful disease. The primary screening of breast tumor is still under research because of some risk features, such as gene, taking birth control pills, smoking, obesity, and age are playing vital role spreading the cancers. The malignant tumors induct into the breast cells and eventually this tumor extends to the surrounding tissues. The proposed technique consists of four steps. Step 1 is for digitized noises removal, step 2 is for suppression of radio opaque artifacts, step 3 is for Pectoral Muscle removal, and step 4 is for detecting location of cancer on breast for emphasizing the region of breast profile. To reveal the capability of this technique, two separate digital mammograms are tested using GT (Ground Truth) mammograms for assessment of performance characteristics. The Experimental results indicate that the breast cancer regions are extracted truthfully in compliance to respective Ground Truth Images. [ABSTRACT FROM AUTHOR]

The use of composite materials to strengthen masonry structures has become common practice within the civil engineering community. Steel-reinforced grout (SRG), which comprises high-strength steel fibers embedded in a mortar matrix, is part of the family of the fiber-reinforced cementitious matrix (FRCM) composites that represent a suitable alternative to fiber-reinforced polymer (FRP) composites for strengthening existing structures. Although studies on FRCMs have already reached a certain level of maturity, some key issues remain open, such as the role of matrix type and layout, substrate properties, and test rate. This paper focuses on some of these issues. The results of single-lap direct shear tests on masonry blocks strengthened with SRGs are presented to analyze the bond behavior between the composite material and the substrate. Four aspects are considered: (1) the change in the width of the SRG mortar matrix while keeping the width of the fiber sheet fixed; (2) the type of mortar used for the SRG; (3) the influence of the test rate, and (4) the type of substrate (i.e., concrete vs. masonry). The results obtained indicate the active role of the matrix layout and the importance of the test rate, encouraging further investigations to clarify these aspects.

We present empirical machine learning algorithms for measuring the probabilistic photometric redshifts (photo-z) of X-ray quasars based on the quantile regression of ensembles of decision trees. Relying on the data of present-day photometric sky surveys (e.g., SDSS, GALEX, WISE, UKIDSS, 2MASS, FIRST), the proposed methods allow one to make high-quality photo-z point predictions for extragalactic objects, to estimate the confidence intervals, and to reconstruct the full probability distribution functions for all predictions. The quality of photo-z predictions has been tested on samples of X-ray quasars from the 1RASS and 3XMM DR7 surveys, which have spectroscopic redshift measurements in the SDSS DR14Q catalog. The proposed approaches have shown the following accuracy (the metrics are the normalized median absolute deviation σNMAD and the percentage of outliers n>0.15): σNMAD, n>0.15 = 0.043, 12% (SDSS + WISE), 0.037, 8% (SDSS + WISE + GALEX) and 0.032, 8.6% (SDSS + WISE + GALEX + UKIDSS) on the RASS sample; σNMAD, n>0.15 = 0.054, 13% (SDSS + WISE), 0.045, 7.6% (SDSS + WISE + GALEX), and 0.037, 6.6% (SDSS + WISE + GALEX + UKIDSS) on the 3XMM sample. The presented photo-z algorithms will become an important tool for analyzing the multi-wavelength data on X-ray quasars in the forthcoming Spectrum-Roentgen-Gamma sky survey. [ABSTRACT FROM AUTHOR]

This paper presents an innovative and effective control strategy of Switched Reluctance Generator (SRG), operating with Vujicic-Calasan PCT1 power converter in continuous-conduction mode (CCM), for a wind energy conversion system (WECS) employed in DC microgrids. The Vujicic-Calasan PCT1 power converter, whose validity in this paper is additionally confirmed through simulations and experimental results, is based on diode bridge rectifiers and does not contain switch components. Namely, it requires four diodes and one inductance filter per machine phases as well as one excitation voltage source. By regulating the dc excitation voltage the output power of SRG can be easily controlled. A procedure for determination of the optimal excitation voltage as a function of rotor speed, that provides maximal output power for defined RMS phase current and voltage is proposed. Moreover, the obtained optimal dependences are mathematically described to be used for control of SRG in WECS. In the simulations performed to study the proposed control strategy, a realistic wind profile is used, while the turbine operation with and without pitch controller is considered. Simulations results provided for the WECS confirm that the proposed control strategy ensures system stability and fast maximal power point tracking. [ABSTRACT FROM AUTHOR]

Textile reinforced mortar (TRM) composites have received much attention as they are a superior sustainable material and physically compatible with masonry and historical structures. Among the numerous materials used in TRM composites, steel reinforced grout (SRG) which is produced with high strength steel cords embedded in a cementitious mortar matrix, demonstrates exceptional mechanical performance at a relatively low cost. In this paper, an experimental investigation is carried out on their use as in-plane shear reinforcement of masonry wall panels. The masonry panels are constructed with grey clay bricks (GCBs), a unique construction material widely used in traditional Chinese architecture. Diagonal compression tests are carried out on two unreinforced panels and six strengthened panels with different reinforcement configurations. The contribution of the SRG system to strengthening is assessed by examining the shear stiffness, shear strength, ductility under shear, and changes in failure mechanisms. A comparative analysis is carried out by using results from the previous literature, and the analytical methodologies and the practical use of the SRG system are also discussed. [ABSTRACT FROM AUTHOR]

A series of D-N=N-A type molecular glasses where the electron acceptor part (A) contains several electron withdrawing substituents, but the electron donating part (D) of the glassy azochromophores contains amorphous phase promoting non-conjugated bulky triphenyl or hydroxyl groups have been synthesized and investigated. Results showed that the azodye physical properties depend not only on the incorporated electron withdrawing substituents but are also influenced by the bonding type of covalently attached bulky moieties. Synthesized glassy azocompounds showed glass transition temperatures up to 106 °C and thermal stability up to 312 °C. The ability to form holographic gratings in spin-cast thin films of the glassy azodyes was investigated using 532 nm and 633 nm lasers obtaining diffraction efficiency up to 57%, self-diffraction efficiency up to 15% and photosensitivity as high as 3.7 J/(cm 2 %). Surface relief grating (SRG) depths reached 1.1 μm and in some cases even exceeded the thickness of the films. [ABSTRACT FROM AUTHOR]

Steel Reinforced Grout (SRG) composites are becoming a common technique for strengthening masonry arches and vaults. These composites are made of Ultra High Tensile Strength Steel unidirectional textiles applied to the substrate by means of inorganic mortar. The structural performance is generally controlled by the bond properties of the interface between the matrix and the textile, which in the case of arches or vaults is also affected by the curved geometry of the substrate. In this work, a closed-form analytical solution of the debonding process of a thin plate bonded to a rigid substrate with constant curvature is proposed. The work provides an upgrade of the model previously proposed by the author [1]. In the present work the substrate curvature is such that the normal stresses arising at the interface are tensile, as in the case of the reinforcement applied to the intrados of the vault [1] or compressive, as for the reinforcement applied to the extrados of the vault. The proposed model describes the interfacial stresses transfer mechanism in the framework of fracture mechanics, adopting two cohesive material laws to model the interfacial behaviour in normal (pure opening mode: Mode I) and in tangential (in plane shear mode: Mode II) direction. The coupling deriving from curvature is introduced directly in the cohesive laws that describe the bond properties. The outcomes of the proposed predictive model are validated by comparing them with the results derived from an experimental campaign of bond tests on straight and curved substrates made of brickwork strengthened with SRG. Finally, a simple design formula for the evaluation of the debonding load of a SRG-masonry joint in the case of curved substrate, is proposed. [ABSTRACT FROM AUTHOR]