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Recursive identification algorithms for jump Markov linear systems and elliptical extended target tracking
No full textReview on DFIG Supplementary SSI Damping Controllers: Design, Development, and Directions
No full textThis paper presents a comprehensive review of the supplementary damping controllers (SDCs) proposed for the mitigation of sub-synchronous interaction (SSI) between doubly-fed induction generator-based wind parks (DFIG-WPs) and series capacitor compensated grids. First, the terms sub-synchronous control interaction (SSCI) and induction generator effect (IGE) are clarified by delineating their occurrence conditions and instability mechanisms in series compensated DFIG-WPs. Then, a generic design and testing framework of SDCs is proposed as a basis including the selection and adjustment of key aspects, and tests of mitigation performance, transient response and practical implementation. SDCs in the existing literature are classified into four main types considering the control structures. Their strengths and limitations are thoroughly discussed. Finally, the future directions are indicated to develop adaptive SDCs with high efficacy and robustness considering data-driven techniques
Synthesis and characterization boron-doped hydroxyapatite for bone tissue engineering applications
No full textIn this study, the effect of dopant ratio on structural and biological properties of B-doped hydroxyapatite (HA) sintered at 500 °C was investigated for the first time. For this purpose, 1, 2, 4 and 8 mol% B-doped HA groups were synthesized. Presence of PO43− and BO33− groups were verified with Fourier-transform infrared spectroscopy (FTIR). X-ray diffraction (XRD) analysis revealed that increasing the B ratio led to a decreasing trend for HA phase percentage, crystallinity, and crystallite size. Similarly, Ca/(P + B) ratio decreased with increasing dopant ratio. B was incorporated into the HA structure with around 50 % yield. Moreover, mean particle size significantly decreased by B-doping for all groups. Concordantly, BET analysis revealed that the surface area of the groups increased with increasing B ratio. Overall, doping of HA with 4 mol% B was shown to provide both proliferative and osteogenic effects on human adipose derived stem cells (hADSCs). Our findings suggest that B-doped HA sintered at 500 °C holds promise for bone tissue engineering applications
Thermal Analysis of Small-Scale Axial Flux Permanent Magnet Synchronous Motors for LVAD Systems
No full textThis paper addresses the design and thermal analysis of Axial Flux Permanent Magnet Synchronous Machines (AFPMSMs) integrated into flow left ventricular assist devices (LVADs). Allowed temperature rise limitation due to medical application was the primary motivation of this research. Thermal challenges are further elevated due to the limited volume, which increases the thermal loading of the motor. Furthermore, effective cooling of both the rotor and stator was achieved, which is an innovative aspect of this work. Within the scope of this study, the thermal aspects of AFPMSMs specifically for LVAD pumps were examined, and their validations were carried out through analytical calculations and simulation studies along with some experimental work. It was validated by the FEA that the temperature of the fluid at the LVAD pump inlet under rated load increased by only 0.04°C. Therefore, the pump design presented does not pose any risks to the patient. Subsequently, to validate the design, an AFPMSM prototype was produced and tested in a laboratory environment. These tests showed that under the rated load, the winding temperature increase was 26.5°C, and the outer case temperature increase was 15.1°C. These results are consistent with both analytical and simulation results. This study demonstrated that the LVAD pump design is thermally suitable and that the established analytical equations are accurate in both simulation and experimental tests. Additionally, the novel integration of AFPMSM and pump yielded significantly higher current-carrying capacity due to the devised effective cooling mechanism
Search for long-lived heavy neutral leptons in proton-proton collision events with a lepton-jet pair associated with a secondary vertex at s = 13 TeV
No full textA search for long-lived heavy neutral leptons (HNLs) using proton-proton collision data corresponding to an integrated luminosity of 138 fb−1 collected at s = 13 TeV with the CMS detector at the CERN LHC is presented. Events are selected with a charged lepton originating from the primary vertex associated with the proton-proton interaction, as well as a second charged lepton and a hadronic jet associated with a secondary vertex that corresponds to the semileptonic decay of a long-lived HNL. No excess of events above the standard model expectation is observed. Exclusion limits at 95% confidence level are evaluated for HNLs that mix with electron and/or muon neutrinos. Limits are presented in the mass range of 1–16.5 GeV, with excluded square mixing parameter values reaching as low as 2 × 10−7. For masses above 11 GeV, the presented limits exceed all previous results in the semileptonic decay channel, and for some of the considered scenarios are the strongest to date
Assessment of urban seismic resilience of a town in Eastern Turkiye: Turkoglu, Kahramanmaras before and after 6 February 2023 M 7.8 Kahramanmaras earthquake
No full textOn 6 February 2023, two earthquakes occurred approximately 9 h apart, with Mw 7.8 and 7.5, and epicenters located in Pazarc & imath;k and Elbistan districts of Kahramanmaras province, respectively. As part of a national project team which was funded by the Disaster and Emergency Management Presidency of Turkiye (AFAD) between June 2021 and June 2023, the authors of this article had proposed a framework to assess the seismic resilience of an urban region. The pilot area of this national project was a small-scale industrial town named Turkoglu located to the south of Kahramanmaras, at the intersection of Amanos and Pazarcik segments of the East Anatolian Fault zone. The proposed framework encompasses the assessment of active faults in the region, construction of regional velocity models, ground motion simulations of potential earthquakes, structural vulnerability, and study of seismic resilience indicators. The Pazarcik earthquake occurred 4 months before the end of the project on the exact fault system, which was modeled in ground motion simulations within the project in 2022. The objective of this article is multifold: first, to present our findings before the earthquake (2021-2022) in the region, including regional velocity models, ground motion simulations, street survey-based building classifications, and vulnerability classes; and second, to compare the after-event modeling of damage distributions in comparison with the observed damages as well as resilience evaluations of the region from multiple perspectives. A third objective is to assess the seismic resilience framework used in the project, as there are multiple seismically active areas in Turkiye and the world where similar large events are anticipated. This study constitutes a significant case study in the Turkoglu region, which involves critical evaluations of seismic resilience from before and after event data
Impact of Food Service Cooking on the Yield and Fat Content of Commercial Ground Meats and a Plant-Based Meat Substitute
No full textCollecting data on cooking yields of different food products is critical for accurately calculating food composition and nutritional changes after food processing. Ground meat is a good example of a food product that will undergo significant yield changes during cooking. This manuscript investigates yield changes as well as changes in fat and moisture content of ground beef, pork, chicken, turkey, and a plant-based meat product cooked in a food service facility. The findings demonstrated a strong relationship between the initial fat content of the meat and yield, with higher fat content resulting in decreased yield. It was also observed that in meats with lower fat content, moisture loss had a bigger impact on yield than fat loss. The findings of this study will help in the calculation of nutritional content of cooked meat and may help in the use of future technologies such as artificial intelligence to estimate the nutritional content of meats
Nickel ferrite platinum nanoparticles: Highly active catalyst in hydrolytic dehydrogenation of ammonia borane
No full textMagnetically separable platinum(0) nanoparticles are obtained by depositing them on the surface of magnetic nickel ferrite powder. The reduction of H2PtCl6 with sodium borohydride on the surface of nickel ferrite powder results in the formation of Pt0/NiFe2O4 nanoparticles, which can be easily isolated from the reaction medium using an exterior magnet. Characterization reveals that platinum(0) nanoparticles are uniformly dispersed on the surface of NiFe2O4 support, with a particle size ranging from 2 to 4 nm. The Pt0/NiFe2O4 nanoparticles with a 0.25 % wt. Pt loading are found to be very active catalyst providing a turnover frequency of 2200 min−1 in releasing H2 from the hydrolysis of ammonia borane at 25.0 °C. Remarkably, the Pt0/NiFe2O4 (0.25 % wt. Pt) nanocatalyst retains 55 % of its initial activity in the fifth run of hydrolysis in the reusability test, still releasing 3 equivalents H2 per mole of ammonia borane. X-ray photoelectron spectroscopy analysis shows the presence of a strong interaction between platinum(0) nanoparticles and nickel ferrite support, which enhances the stability and catalytic activity of the Pt0/NiFe2O4 nanocatalyst. Such a strong platinum-support interaction is responsible for holding the nanoparticles tightly on the oxide surface and leads to a charge transfer from platinum(0) nanoparticles to support surface which is favorable for the catalytic activity
The Role of the State in the Big Picture of Economic Development: Mainstream-versus-Heterodox Approaches and Historical Evidence
No full textThis paper purports to develop a double critique, (1) an institutional and historical critique of mainstream development literature, and (2) a critique of heterodox approaches to development. Concerning the first, it demystifies the myth of the liberal state and highlights that the liberal state was economically proactive even when it chose not to intervene, and that the zero-sum notion of the total realm as shared among the state and market on which the myth rested is far from correct. In relation with the second, it stresses the superior performance of heterodoxy but argues that it should resist to imitate its adversary by falling prey to formulating a singular alternative development policy. It ends by disclosing a rationale as to why state remains important yet with a changing contextual function all along, as a specific instance of a more general conception of development based on the principle of advantageous ‘repetition with a difference’
Boron Salicylate Ester Compounds as Boron Therapeutics. Their Synthesis, Structural Characterizations and Anticancer Effects against MDA-MB-231
No full textThe element boron forms a wide range of borate minerals with different properties. Borate minerals make it possible to design boron-containing molecules with new biological properties in terms of their chemical structure and properties. It is known that boron compounds have antioxidant, anti-inflammatory, anti-tumor and anti-cancer properties. This makes boron compounds important for the future development of boron chemotherapeutics, boron supplements and new drugs. Reliable scientific studies on boron compounds will facilitate the clear presentation of their functions in its biological applications and metabolism. In this study, boron monoester and boron diester structures were synthesized with salicylic acid ligand. To stabilize boron ester structures, Na+, K+, Mg2+, Ca2+ cations were used as counter-ions. Structural properties of the synthesized substances, molecules obtained by crystallization/precipitation from aqueous solutions in solid state, elemental analysis, melting point determination, infrared spectroscopy analysis (FT-IR), thermal analysis (TGA/DTA), mass analysis (GC–MS) and single crystal analysis. Structural properties were tried to be explained by structure analysis (SC-XRD) methods. Additionally, the anticancer potential of boron salicylate esters against the MDA-MB-231 human breast adenocarcinoma cell line was examined. The K-B salicylate diester molecule was found to have the most potential potency with the lowest IC50 value against the MDA-MB-231 cell line. The anticancer potential of boron salicylate esters can be further investigated with other cancer models with the combination of anticancer drugs. It is also thought that the mechanism of action of these molecules may help reveal their further applications