Shear strength estimation of reinforced concrete beam–column sub‐assemblages using multiple soft computing techniques

The aim of the present study is to propose innovative predictive models for shear capacity of reinforced concrete (RC) exterior joints in terms of multiple soft computing techniques. Existing models were evaluated and by a preliminary sensitivity analysis, seven parameters including compressive strength of concrete, product of the yield stress and the reinforcement ratio of the joint stirrups, the effective width of the joint panel, cross‐sectional column width, beam tensile longitudinal reinforcement ratio, beam compressive longitudinal reinforcement ratio, and column longitudinal reinforcement ratio were considered. Then, a large data set having the details of experimental programs on shear capacity of exterior RC beam–column joints was provided. The experimental data were utilized in developing the proposed models. After verification of the new models against available database, their efficiency compared with existing models was confirmed. Finally, a sensitivity analysis was performed in order to find the relative importance of each input parameter on the shear strength of RC joints. The results indicated that the beam reinforcement is the most important factor in shear capacity estimation of exterior RC beam–column connections.     

Inhibitory effect of anthraquinones isolated from the Noni (Morinda citrifolia) root on animal A-, B- and Y-families of DNA polymerases and human cancer cell proliferation

During the course of our studies to develop new uses for the Noni (Morinda citrifolia) root, 10 anthraquinones, rubiadin (1), rubiadin 1-methyl ether (2), lucidin (3), damnacanthol (4), 1,3-dihydroxy-2-methoxymethylanthraquinone (5), 3-hydroxy-1-methoxy-2-methoxymethylanthraquinone (6), nordamnacanthal (7), damnacanthal (8), sorandidiol (9) and morindone (10), were isolated. Compounds 5, 6, 7, 8 and 10 exhibited remarkable inhibition against the activities of animal pols, and compound 10 was the strongest inhibitor in the anthraquinones investigated. Among mammalian pols, compound 10 inhibited the pol activities of A- (pol γ), B- (pols α, δ and ε) and Y- (pols η, ι and κ) families, but did not influence the activities of X-family pols (pols β, λ and terminal deoxynucleotidyl transferase). The tendency of pol inhibition showed a positive correlation with the suppression of human colon cancer cell HCT116 growth. These results suggested that the Noni root containing anthraquinones may be used as an anticancer functional food.     

Design of a Full-Consensus Glutamate Decarboxylase and Its Application to GABA Biosynthesis

Glutamate decarboxylase (GAD) catalyses the decarboxylation of L-glutamate to gamma-aminobutyric acid (GABA). Improvement of the enzymatic properties of GAD is important for the low-cost synthesis of GABA. In this study, utilizing sequences of enzymes homologous with GAD from lactic acid bacteria, highly mutated GADs were designed using sequence-based protein design methods. Two mutated GADs, FcGAD and AncGAD, generated by full-consensus design and ancestral sequence reconstruction, had more desirable properties than native GADs. With respect to thermal stability, the half-life of the designed GADs was about 10 °C higher than that of native GAD. The productivity of FcGAD was considerably higher than those of known GADs; more than 250 mg/L of purified enzyme could be produced in the E. coli expression system. In a production test using 26.4 g of l -glutamate and 3.0 g of resting cells, 17.2 g of GABA could be prepared within one hour, without purification, in a one-pot synthesis.     

A Monolayer MoS2 FET with an EOT of 1.1 nm Achieved by the Direct Formation of a High-κ Er2O3 Insulator Through Thermal Evaporation

Achieving the direct growth of an ultrathin gate insulator with high uniformity and high quality on monolayer transition metal dichalcogenides (TMDCs) remains a challenge due to the chemically inert surface of TMDCs. Although the main solution for this challenge is utilizing buffer layers before oxide is deposited on the atomic layer, this method drastically degrades the total capacitance of the gate stack. In this work, we constructed a novel direct high-κ Er₂O₃ deposition system based on thermal evaporation in a differential-pressure-type chamber. A uniform Er₂O₃ layer with an equivalent oxide thickness of 1.1 nm was achieved as the gate insulator for top-gated MoS₂ field-effect transistors (FETs). The top gate Er₂O₃ insulator without the buffer layer on MoS₂ exhibited a high dielectric constant that reached 18.0, which is comparable to that of bulk Er₂O₃ and is the highest among thin insulators (< 10 nm) on TMDCs to date. Furthermore, the Er₂O₃/MoS₂ interface (D_it ≈ 6 × 10¹¹ cm⁻² eV⁻¹) is confirmed to be clean and is comparable with that of the h-BN/MoS₂ heterostructure. These results prove that high-quality dielectric properties with retained interface quality can be achieved by this novel deposition technique, facilitating the future development of 2D electronics.     

Real-time supply-demand schedule update and operation for generators and battery energy storage system based on forecasted and actual photovoltaic power outputs

The photovoltaic (PV) power output might be frequently curtailed to maintain electricity supply-demand balance in future power systems. In our previous study, we proposed a new method for updating the battery energy storage system (BESS) charge/discharge and the generator unit commitment (UC) schedules based on the forecasted and actual PV power outputs. The forecast dataset was updated every 3 h (eight times a day). Although the simulation results showed that the proposed method could reduce the supply-demand imbalances, it was not clear whether the forecasted or actual values made contributions. Therefore, in this study, we propose and evaluate a real-time scheduling and operation method using the forecasted and actual PV power outputs assuming that the forecasted dataset is updated only once a day. Numerical simulations of supply-demand operations are conducted on the power system model of the Kanto area of Japan for one year. The results show that the previous study method has a slight advantage over proposed method in terms of curtailed PV energy and operational cost of thermal generators reduction, but the difference is very small, indicating that the contribution of the actual PV power outputs is greater than that of the forecasted PV power outputs.     

Impact of the O/P ratio on the optical properties and structures of fluoride–phosphate glass

Ca(PO₃)₂–AlF₃–CaF₂–BaF₂–BaO glasses were prepared by the melt quenching method, and the effects of the O/P ratio on the optical properties and glass structure were investigated. The bandgap energy showed no significant change at O/P = 3.0–3.4 but drastically decreased with the increase in the O/P from 3.6 to 4.0. In addition, the refractive index dispersion was analyzed based on the Lorentz model, and it was found that the decrease in the resonance frequency in the ultraviolet region with the increase in the O/P ratio resulted in an increase in the refractive index and dispersion. Analysis of the infrared absorption and Raman scattering spectra revealed that the phosphate chains were broken, and isolated Q⁰ units were generated with the increase in the O/P ratio from 3.6 to 4.0. Based on the structural change of the glass, the origin of the nonlinear dependence of the optical properties on the O/P ratio was discussed.     

Lattice misorientation at domain boundaries in β-Ga2O3 single-crystal substrates observed via synchrotron radiation X-ray diffraction imaging and X-ray reticulography

To evaluate the lattice misorientation at domain boundaries (DBs) in β-Ga₂O₃, we performed X-ray diffraction imaging (XRDI), X-ray reticulography (XRR), and X-ray topography (XRT) using a synchrotron radiation light source. Four reciprocal lattice vectors ( g -vectors) were applied, and the DBs showed different visibilities in the XRDI maps depending on the g -vector. By analyzing possible characteristics of the misorientation, the XRDI results suggested that the DB being investigated was associated with a misorientation on the ($\overline{10}05$) plane and contained twist and tilt components. The apparent peak change in XRDI caused by the two components was calculated. We further succeeded in separating the tilt and twist components using XRR images in conjunction with simulation. Dislocation arrays at the DBs were observed using XRT, and the average distance between the dislocations in the array was consistent with the misorientation obtained using XRDI and XRR. The distribution of DBs across a wide area was acquired by a combination of XRR images recorded on a charge-coupled device camera and X-ray films. The fringe-patterned XRR on X-ray films provided a powerful and nondestructive tool to characterize DBs distributed across a large-diameter wafer with an angular resolution on the order of several arc sec (low 10⁻⁵ rad).     

Definition of an Index Parameter To Screen Highly Functional Enzymes Derived from a Biochemical and Thermodynamic Analysis of Ancestral meso-Diaminopimelate Dehydrogenases

Sequence-based protein design approaches are being adopted to generate highly functional enzymes; however, screening the enzymes remains a time-consuming task. In this study, by analyzing the enzymatic properties of four ancestral meso-2,6-diaminopimelate dehydrogenases (AncDAPDHs), AncDAPDH-N1, -N2, -N3, and -N4, we attempted to define a new index parameter that is helpful for efficiently screening the enzymes. Biochemical and thermodynamic analyses indicated that only AncDAPDH-N4 exhibited greater thermal stability than and activity similar to those of native DAPDHs. Structural and sequence comparisons between DAPDH from Corynebacterium glutamicum (CgDAPDH) and the AncDAPDHs suggested that “quality of mutations” is a potential index parameter. In fact, the mutations introduced from CgDAPDH to AncDAPDH-N4 correlated highly with the mutations accumulated during the evolution process from mesophiles to thermophiles. These results suggest that, although there are several exceptions, the correlation coefficient can be used as an index parameter for screening high-functioning enzymes from sequence data.     

Connection of nonlinear model predictive controllers for smooth task switching in autonomous driving

Motion planning, decision making, and control are vital functions in autonomous driving for accomplishing the desired driving task while considering passenger comfort, road infrastructure, and surrounding traffic participants. Model predictive control (MPC) is a promising method for simultaneously realizing these functions. However, formulating a single MPC that can run through all driving scenarios is difficult, and previous research has often been conducted to design an MPC for a specific driving task. To extend the availability of MPC for all driving tasks, smooth switching between different MPCs designed for each driving task must be addressed. One of the difficulties in switching between MPCs is guiding the state to a feasible set of optimization problems after switching. In this paper, we present a new framework to realize the smooth connection of MPCs, that is, to reduce the optimization infeasibility at the time of MPC switching. In our proposed method, two general nonlinear MPCs with different state spaces, cost functions, constraints, and formulations can be systematically switched via automatically generated intermediate-MPCs without requiring any particular alterations. This can help reduce the system complexity of the hybrid MPC system.