Current Phase Research Articles

Высокодинамичная компенсация «мертвого времени» в электрических приводах на базе сигнальной адаптации

The article discusses the analysis and synthesis of a system of highly dynamic "dead time" compensation in the current loop of motors powered from transistor pulse-width converters. The first part of the paper provides a brief analysis of existing technical solutions, whose algorithms do not imply changes or additions to the power part of the drive and therefore are implemented exclusively by software. It is shown that the most modern methods of adaptive compensation can be considered using reference models of the control object. A non-search adaptive dead-time compensation system is proposed in the paper which provides signal self-tuning in the motor current loop, and dead-time compensation is based not on linearization or correction of nonlinear effects and delays of a pulse-width converter, but on parrying disturbing influences caused by the negative effects of “dead time”. Particular attention is paid to the practical orientation of the proposed solution; therefore, the considered algorithm is based solely on the basic principles of the control theory proven by practice. This approach allows us to ensure not only the transparency of the theoretical arguments presented in the article, but also reduce the time spent on the analysis and synthesis of the current loop, the purpose of which, ultimately, is the optimization of high-precision drives. With the absence of iteration methods of mathematics, the resources of microprocessor control units are minimized, which makes this method even more attractive in low-budget drives that do not claim to "exclusivity of integrated circuitry. The proposed algorithm was integrated into the existing current loop of an asynchronous electric drive with vector control, which proved the high efficiency of static and dynamic compensation of not only the “dead time” of the converter, but also of the non-linear effects associated with it that are difficult to analyze. The adaptive "dead time" compensation increased the efficiency of the electric drive at low motor speeds, compared to voltage boost compensation, by approximately four percent, and also reduced the motor torque ripple by about seventeen percent. An oscillogram of the phase current of a real drive with "dead time" compensation is given according to the principle of parametric voltage addition, which is the most common in practice, as well as a waveform of current with adaptive compensation action according to the principle considered in this article.

Stator ITSC Fault Diagnosis for EMU Induction Traction Motor Based on Goertzel Algorithm and Random Forest

The stator winding insulation system is the most critical and weakest part of the EMU’s (electric multiple unit’s) traction motor. The effective diagnosis for stator ITSC (inter-turn short-circuit) faults can prevent a fault from expanding into phase-to-phase or ground short-circuits. The TCU (traction control unit) controls the traction inverter to output SPWM (sine pulse width modulation) excitation voltage when the traction motor is at a standstill. Three ITSC fault diagnostic conditions are based on different IGBTs’ control logics. The Goertzel algorithm is used to calculate the fundamental current amplitude difference Δi and phase angle difference Δθ of equivalent parallel windings under the three diagnostic conditions. The six parameters under the three diagnostic conditions are used as features to establish an ITSC fault diagnostic model based on the random forest. The proposed method was validated using a simulation experimental platform for the ITSC fault diagnosis of EMU traction motors. The experimental results indicate that the current amplitude features Δi and phase angle features Δθ change obviously with an increase in the ITSC fault extent if the ITSC fault occurs at the equivalent parallel windings. The accuracy of the ITSC fault diagnosis model based on the random forest for ITSC fault detection and location, both in train and test samples, is 100%.

Observation of half-integer Shapiro steps in graphene Josephson junctions

We study quantum transport and AC Josephson effect of hexagonal boron nitride encapsulated graphene (BGB) Josephson junctions (JJs). Our experiments reveal the emergence of the half-integer Shapiro steps in the n-type regime with high electron carrier densities. We attribute this observation to the gate-tunable transmission probability of the graphene junction. Our numerical simulations are consistent with the appearance of half-integer Shapiro steps at high transparency, which suggests a skewed current phase relationship in the graphene JJ.

Optimal design and control of hybrid synchronous generator regulating turbine angular speed for turbine protection

In this paper is presented a methodology of systemic design and control of a synchronous generator with hybrid excitation for the generation of wind energy. The design of the generator is made by the analytical method taking into account the interactions of the global system. Indeed, the regulation of the speed of the turbine is ensured by adjustment of the excitation current to regulate the electromagnetic torque and in this case the excitation current is limited to a fixed value since the increase of excitation current leads to an increase generator’s phase currents magnitude. The increase of the phase’s currents of the generator is linked to the increase of the amplitude of the electromotive forces depending on the excitation current. Therefore, to limit the amplitude of the phase’s currents to the value of the design current fixed by the note book specifications for a given power of the wind turbine, it is necessary to limit the excitation current by limiting the supply voltage of the DC-DC converter used to vary the excitation current for the regulation of the electromagnetic torque. This technique of speed adjustment is simpler and less expensive than techniques using mechanical and hydraulic braking systems.

A steps-ahead tool wear prediction method based on support vector regression and particle filtering

This paper develops a steps-ahead tool wear prediction method based on particle filtering and support vector regression. A degradation phase classification method is presented based on clustering algorithm and support vector machine. The support vector regression models are established to achieve the mapping between degradation features and the flank tool wear values. In online prediction, the measured signals are input into the SVM model to judge the current phase of the tool, and the particle filtering algorithm is used for online steps-ahead prediction of the features. The prediction of tool wear can be obtained by inputting the feature prediction results into the SVR models. The experimental tool wear dataset is introduced as an application example to test the proposed method. The results demonstrate the effectiveness of the proposed method, and the comparison with other tool wear prediction shows the advantage of the proposed method in prediction accuracy.

Neural Network Predictive Control for Improved Reliability of Grid-Tied DFIG-Based Wind Energy System under the Three-Phase Fault Condition

This research explores a distinctive control methodology based on using an artificial neural predictive control network to augment the electrical power quality of the injection from a wind-driven turbine energy system, engaging a Doubly Fed Induction Generator (DFIG) into the grid. Because of this, the article focuses primarily on the grid-integrated wind turbine generation’s dependability and capacity to withstand disruptions brought on by three-phase circuit grid failures without disconnecting from the grid. The loading of the grid-integrated power inverter causes torque and power ripples in the DFIG, which feeds poor power quality into the power system. Additionally, the DC bus connection of the DFIG’s back-to-back converters transmits these ripples, which causes heat loss and distortion of the DFIG’s phase current. The authors developed a torque and power content ripple suppression mechanism based on an NNPC to improve the performance of a wind-driven turbine system under uncertainty. Through the DC bus linkage, it prevented ripples from being transmitted. The collected results are evaluated and compared to the existing control system to show the advancement made by the suggested control approach. The efficacy of the recommended control methodology for the under-investigation DFIG system is demonstrated through modelling and simulation using the MATLAB Simulink tool. The most effective control technique employed in this study’s simulations to check the accuracy of the suggested control methodology was the NNPC.

Runaway electron mitigation with pulsed localized vertical magnetic field perturbation in ADITYA tokamak

To reduce the risk of severe damage to the vessel and inner peripherals of any tokamak and its safe operation, a robust technique for the mitigation of runaway electrons (REs) is required. The REs in ADITYA tokamak are effectively mitigated by an application of local vertical magnetic field (LVF) perturbation. The LVF perturbation is applied using a pair of electromagnetic coils placed at the top and bottom of the ADITYA vacuum vessel in a Helmholtz configuration at one toroidal location. Powered by a capacitor bank power supply, these coils can produce a localized vertical magnetic field at the plasma center in the range of ∼150 G–260 G for a variable duration of 5–20 ms. The LVF pulse is first applied at the breakdown/current-ramp phase, where the REs are generated in the discharges initiated by the conventional ohmic breakdown in ADITYA. With the application of LVF pulse the REs are significantly reduced as indicated by the reduction in the REs generated hard x-ray flux. It has been observed that to extract the REs efficiently, an LVF pulse of magnitude at least ∼1% of the toroidal magnetic field with a minimum duration of ∼5 ms should be applied. The LVF perturbation is applied at different times into the discharge, i.e. during the breakdown/current ramp-up phase and current flat-top phase. The REs are significantly reduced in all the phases and improved discharge consistency. The LVF acts as an error field and a short-pulse of the LVF influences the REs more in comparison to the thermal electrons due to the faster velocities of the REs.

Development of a Methodology for Assessment and Analysis of the Export Conjuncture of Russian Manufacturing Enterprises

The article explains the current methodological approaches to the analysis of the export conjuncture (on the example of Russian ma nufacturing enterprises), including a new methodology for its integral assessment. This assessment is made by modeling the global demand for domestic products and their price competitiveness in the international market.The importance of the analysis of the current phase of Russia's economic development is emphasized, when a structural transformation of industrial and export policy is taking place and a new contour of foreign economic activity is being formed. This necessitates the improvement of methods for export climate assessment. The author underlines the relevance of using not only qualitative and quantitative indicators, but also their hybrid modifications in the economic and statistical analysis of export trends. The article presents a new hybrid measure – the Export Climate Index (ECI), which aggregates the indicators of demand for domestic manufactured goods and their price competitiveness in the international market. The methodology for its calculation is based on theoretical developments, adapted to the specifics of the Russian economy, and the best world practices for measuring and analyzing export trends.The quantified results of business and consumer surveys in the countries that are Russia's main trading partners, as well as the real effective exchange rate of the ruble according to the Bank of Russia, are used for empirical calculations.The calculations results revealed a significant leading correlation between the ECI dynamics and the dynamics of the referent – the indicator of export of goods in value terms, confirming the possibility of using the new index not only for an integral assessment of the export climate in Russia, but also as a short-term predictor that effectively supplements statistical measures.

Data window selection for removal of decaying DC component in current phasor estimation for distance protection

In distance protection, the fault current signal is usually distorted by the decaying direct current (DC) and harmonics preventing accurate and fast estimation of the fault current phasor. This paper presents a method based on the carefully selected data windows and least square (LSQ) method to improve the performance of the current phasor estimation. The method comprises a short and variable data window for fast operation of distance relay for close faults and a fixed data window for the accurate operation of the relay for faults close to the boundary of Zone 1. The short and variable data window can achieve high speed in the phasor estimation in a quarter of cycle, whereas the second algorithm uses a fixed data window with an excellent frequency response to increase the accuracy of the phasor estimation. The proposed method is first tested using mathematical formulation under different conditions such as different characteristics of the DC component, noise, harmonics and frequency deviation. Then the method is tested by more realistic samples taken from a simulated transmission system under different fault conditions for flexibility, speed and accuracy. All the test results validate the aforementioned features of the proposed algorithms.

Unbalanced Current Identification of Three-Core Power Cables Based on Phase Detection of Magnetic Fields

Identifying unbalanced phase currents is crucial for control and fault alarm rates in power grids, especially in urban distribution networks. The zero-sequence current transformer, specifically designed for measuring unbalanced phase currents, offers advantages in measurement range, identity, and size, compared to using three separate current transformers. However, it cannot provide detailed information on the unbalance status beyond the total zero-sequence current. We present a novel method for identifying unbalanced phase currents based on phase difference detection using magnetic sensors. Our approach relies on analyzing phase difference data from two orthogonal magnetic field components generated by three-phase currents, as opposed to the amplitude data used in previous methods. This enables the differentiation of unbalance types (amplitude unbalance and phase unbalance) through specific criteria and allows for the simultaneous selection of an unbalanced phase current in the three-phase currents. In this method, the amplitude measurement range of magnetic sensors is no longer a critical factor, allowing for an easily attainable wide identification range for current line loads. This approach offers a new avenue for unbalanced phase current identification in power systems.

Modelling and Analysis of Inter-Turn Short-Circuit Faults for Large-Power SPM Wind Generators

This paper proposes a general analytical model for large-power surface-mounted permanent magnet (SPM) wind generators under inter-turn short-circuit (ITSC) faults. In the model, branch currents rather than phase currents are used as state variables to describe the electromagnetic behavior of the faulty machine. In addition, it is found that the multiphase Clarke transformation can be used to simplify the proposed fault model with the inductances calculated analytically or numerically using finite element analysis. With the latter, both linear and nonlinear inductances can be obtained, and the non-linear inductances are used for the fault modelling of large power rating machines due to larger electrical loading and heavier magnetic saturation. With the developed fault model, studies of scaling effects (different power ratings such as 3 kW, 500 kW and 3 MW) and the influence of fault location on the electromagnetic performance of SPM generators with series-parallel coil connections have been carried out. The simulation results show that large-power SPM wind generators are vulnerable to ITSC faults when a relatively small number of turns are short-circuited and a single-turn short-circuit fault at the top of the slot is found to be the worst case.

Fault Control Strategy of Grid‐Forming Converter Considering the Voltage Support of Faulty Phase

AbstractThe grid‐forming converter (GFC) is used to regulate the voltage and frequency of a local grid. However, due to the limited current capacity, the GFC must actively modify its control strategy when a serious external fault occurs, thus to avoid the possible damage caused by overcurrent. This paper proposes a novel voltage reference generation method for GFC based on the external equivalent impedance magnitude (EEIM), which has the following merits: (i) the faulty phase currents and the non‐faulty phase voltage can be controlled within their operational limits. (ii) The voltage reference unbalance factor (VRUF) of the GFC can be adjusted flexibly if necessary. Then, in order to achieve the optimal support effect for the faulty phase voltages, a two‐stage GFC fault control strategy is proposed in this paper. In the first stage, the fault type is judged by computing and comparing the EEIM of each phase. In the second stage, the voltage reference mode is determined according to the fault type, and the VRUF is adjusted to its optimum value through a search algorithm. Simulation results based on Matlab/Simulink verify the effectiveness of the proposed GFC fault control strategy in terms of current limiting and faulty phase voltage support. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

The Neutral Voltage Difference Signal as a Means of Investigating Eccentricity and Demagnetization Faults in an AFPM Synchronous Generator

This article investigates the neutral voltage difference signal, VNO signal, for fault diagnosis. The aforementioned signal is the signal of the voltage between the common star point of the stator and the common star point of the load. The under-study faults are demagnetization and static eccentricity faults, while the machine in which the faults are investigated is an axial flux permanent magnet (AFPM) synchronous generator, suitable for wind power applications. This study was conducted using a 3D finite element method (3D-FEM), and the machine’s FEM model was validated through experiments. This method is one of the most accurate methods for electrical machine computation, allowing for a detailed study of electromagnetic behavior. The components that constitute the VNO signal were determined using a 3D-FEM software program (Opera 18R2). Subsequently, further analysis was performed using MATLAB R2022b software, and a fast Fourier transform (FFT) was applied to this signal. In all the investigated faulty cases, new harmonics appeared, and the healthy amplitudes of most of the already existing harmonics increased. These findings can be used for fault identification. The analysis revealed that the harmonic frequency of 1.5fs was the most dominant in the case of demagnetization, while in the case of static eccentricity, the most dominant harmonic was a frequency equal to the machine’s operating frequency, fs. The novelty of this study is that this signal has not previously been used for fault identification, especially in AFPM synchronous machines. This signal depends on EMF voltage and stator phase currents but is less sinusoidal. Consequently, it can detect faults in cases where the aforementioned signals cannot be used for detection.

#4463 JAPANESE AND WHITES SHARE SIMILAR IPTACOPAN PHARMACOKINETICS AND PHARMACODYNAMICS

Abstract Background and Aims Iptacopan (LNP023) is a first-in-class, oral, proximal complement inhibitor that specifically binds to Factor B and inhibits the alternative complement pathway (AP). Current Phase III studies of iptacopan focus on diseases associated with AP activation, such as paroxysmal nocturnal hemoglobinuria, C3 glomerulonephritis, IgA nephropathy, and atypical hemolytic uremic syndrome. These studies are enrolling patients across geographical regions and ethnicities, including those from Japan. The aim of this study was to evaluate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of iptacopan in Japanese patients. Method CLNP023 × 1102 was a randomized, subject-blinded, placebo-controlled, single-dose Phase I study conducted in Japan in healthy Japanese male subjects to assess safety, tolerability, PK, and AP blood biomarkers (Wieslab, Bb) in three dose cohorts, 25, 100, and 400 mg (8 active/2 placebo per cohort). Subjects were dosed on day 1 and observed for 96 hours post-dose. PK and PD data from this study was compared to White data from the similarly designed, previous CLNP023 × 2101 first-in-human study. Results Iptacopan was well tolerated in both Japanese and White subjects. White subjects were on average 15.7 years older and 19.5 kg heavier than Japanese subjects. Iptacopan mean (±SD) Cmax and AUCinf as well as mean (±SD) % change from baseline at 12 hours post-dose for Wieslab and Bb by dose are shown in the table below. All three dose groups manifested a general trend of increased systemic exposure and increased AP biomarker inhibition with increasing dose in both Japanese and White subjects. Conclusion Japanese and White healthy subjects had similar PK and PD results at all dose levels. The slightly higher Cmax and AUCinf in Japanese subjects may be explained in part by the lower average weight of these subjects. This study provides reassurance that there are no clinically meaningful differences in the human pharmacology of iptacopan between these ethnic groups.

#3278 HUMAN PHARMACOKINETICS OF MULTIPLE, STEADY-STATE DOSING OF IPTACOPAN

Abstract Background and Aims Iptacopan (LNP023) is a first-in-class, oral, proximal complement inhibitor that specifically binds to Factor B and inhibits the alternative complement pathway (AP). Current Phase III studies of iptacopan focus on diseases associated with AP activation, such as paroxysmal nocturnal hemoglobinuria, C3 glomerulonephritis, IgA nephropathy, and atypical hemolytic uremic syndrome. Early modeling efforts suggested that an iptacopan concentration of ∼1000 ng/mL would provide near-maximal AP inhibition. The aim of this study was to evaluate the PK of oral iptacopan in healthy subjects to determine the dose that results in a ∼1000-ng/mL mean steady-state concentration over the entire 12-h dosing interval. Method In this blinded, controlled, randomized study, a total of 32 healthy subjects were enrolled into 5 cohorts receiving twice-daily dosing for 14 days: placebo (n = 8) or iptacopan 25, 50, 100, or 200 mg (n = 6 per group). Plasma iptacopan concentration was intensively measured for 72 hours post day 14 dose using a validated LC-MS/MS assay (LLOQ = 1 ng/mL). Results Iptacopan treatment was safe and well tolerated at all dose levels. Iptacopan steady-state concentration-time curves are shown below. Iptacopan was rapidly absorbed, with a median Tmax of approximately 2 hours (Figure 1). The mean half-life was moderately long at 18 to 25 hours. The inter-subject variability (CV%) of iptacopan Cmax and AUCinf was low at approximately 12% to 27%, and both parameters were under-dose proportional with increasing dose. At all time points from 0 to 12 hours, mean iptacopan concentration for the 200-mg dose cohort was >1000 ng/mL. Conclusion Iptacopan was rapidly absorbed, had low inter-subject variability, and a moderately long half-life. Only the 200-mg b.i.d dose produced mean iptacopan concentrations of ≥1000 ng/mL over the dosing interval, and thus is expected to result in near-complete, continuous AP inhibition. These results support the rationale for use of iptacopan 200 mg twice daily as the therapeutic dose in ongoing clinical trials and provide evidence of durable AP inhibition in patients administered oral iptacopan therapy.

#5734 RENAL AUTOLOGOUS CELL THERAPY (REACT™) FOR DIABETIC CHRONIC KIDNEY DISEASE: PHASE II TRIAL WITH BILATERAL CORTEX INJECTIONS AND RE-DOSING TRIGGERS

Abstract Background and Aims Well-based therapies may repair diseased nephrons and stabilize and enhance kidney function to delay the onset of end-stage kidney disease and improve co-morbidities. REACT™ is a novel product formed of cryopreserved autologous homologous selected renal cells, undergoing phase III clinical trials for diabetic kidney disease (DKD). We describe an open label phase II study to evaluate how patients respond to REACT™ injections in both kidneys and a redosing trigger, as being evaluated in a Phase III blinded data trial (proact 1 & 2 trials). Method REGEN 007 is a multi-center Phase II, open label 1:1 randomized controlled trial enrolling up to 50 patients ages 30-80 years with DKD, who have an eGFR of 20 - 50 mL/min/1.73 m2. Each patient undergoes a percutaneous kidney biopsy and ex vivo culture expansion of their selected renal cells. Patients are then randomized to an arm where they receive two REACT™ injections, one in each kidney, three months apart if they meet inclusion criteria, or an arm with an initial single REACT™ dose in one kidney and a 2nd REACT™ dose in the contralateral kidney > 90 days apart, based on a sustained eGFR decline of ≥ 20%, and/or an increase in the urine albumin to creatinine ratio (UACR) from baseline of ≥ 30% and ≥ 30 mg/g. CT-guided bilateral percutaneous renal cortex injections of REACT™ are performed under conscious sedation. Trial design, inclusion and exclusion criteria can be found at the National Clinical Trial Registry (Trial number 05018416). Results Thirty-one of the targeted 50 participants have been enrolled with the following characteristics at screening: 64.0% males, 97.0% Non-Hispanic/Latino. Mean age 62.9 years, serum creatinine (sCr) 2.0 mg/dL ±0.50, Cystatin C 2.0 mg/L ±0.40, eGFR (sCr + Cystatin C) 31.2 ml/min/1.72m2 ±7.88, HgbA1C 7.4% ± 1.14, Hgb 12.9 g/dL ± 1.78, K+ 4.6 mEq/L ± 0.44, Bicarbonate 20.3 mEq/L ± 3.0, and a median UACR 662 mg/g [SD 705.8]. Percent baseline medications are: Angiotensin Converting Enzyme inhibitors 25.8, Angiotensin Converting Enzyme receptor Blockers 48.4, beta blockers 64.5, diuretics 64.4, glucose lowering agents 100, Sodium glucose Cotransporter 2 inhibitors 32.3, and platelet inhibitors 67.7. Efficacy endpoint is an eGFR slope improvement from first injection to 18 months after last injection. REACT™ and procedure related serious adverse events are expected to be commensurate with ongoing trials and standard of care Conclusion REACT™ cell-based therapy has the potential to effect nephron structure and function by stabilizing or improving DKD progression and its comorbidities. Current phase II and III trials are underway to determine efficacy, safety, renal function-dependent dosing, and time to treatment with bilateral kidney injections of REACT™.

#4447 EFFECT OF RENAL IMPAIRMENT ON IPTACOPAN PHARMACOKINETICS

Abstract Background and Aims Iptacopan (LNP023) is a first-in-class, oral, proximal complement inhibitor that specifically binds to Factor B and inhibits the alternative complement pathway (AP). Current Phase III studies of iptacopan focus on diseases associated with AP activation, such as paroxysmal nocturnal hemoglobinuria (PNH), C3 glomerulonephritis (C3G), IgA nephropathy (IgAN), and atypical hemolytic uremic syndrome. The liver is the primary route of iptacopan elimination. Based on a previous healthy volunteer pharmacokinetic (PK) study, the contribution of the renal route of iptacopan elimination was measured to be low, approximately 14%. A population PK (PopPK) analysis was done to further quantify the effect of renal impairment on iptacopan PK. Method A PopPK dataset pool was created by pooling across 6 Phase II/III studies in PNH, C3G, and IgAN indications. The pool comprised patient data on the two highest dose levels (100 and 200 mg bid) and included 2439 datapoints in 234 unique patients. Factors (baseline characteristics) that could possibly affect exposure, body weight, age, gender, ethnicity, and eGFR (mL/min/1.73 m2) at baseline were investigated. The range of eGFR was 27.4 to 142.8 mL/min/1.73 m2. Age, ethnicity, and body weight were included as the significant covariates in the final model. Results The median eGFR was 87.5 mL/min/1.73 m2. As shown in the table below, the PopPK model detected a significant (p = 4.3 × 10−11) but modest effect of eGFR on simulated mean AUC0-24. At an eGFR of 34.3, AUC0-24 is expected to increase by only 38%, compared with median eGFR. Changes of eGFR of ≤15% with respect to median eGFR were observed with eGFR range between 59.7 and 132.0 mL/min /1.73 m2. Conclusion Consistent with previously observed primarily hepatic clearance of iptacopan in preclinical and clinical studies, renal impairment down to an eGFR of 34.3 did not have a clinically meaningful effect on iptacopan PK. Currently, iptacopan PK in patients with eGFR <30 mL/min/1.73 m2 is being explored. These results support the use of iptacopan in patients with mild and moderate renal impairment.

Nonsinusoidal current-phase relations in semiconductor–superconductor– ferromagnetic insulator devices

Coherent tunneling processes of multiple Cooper pairs across a Josephson junction give rise to high harmonics in the current phase relation. In this work, we propose and study Josephson junctions based on semiconductor--superconductor--ferromagnetic insulator heterostructures to engineer nonsinusoidal current-phase relations. The gate-tunability of the charge carriers' density in the semiconductor, together with the adjustable magnetization of the ferromagnetic insulator, provides control over the content of the supercurrent harmonics. At finite exchange field, hybrid junctions can undergo a $0 -- \ensuremath{\pi}$ phase transition, resulting in a supercurrent reversal. Close to the transition, single-pair tunneling is suppressed and the current-phase relation is dominated by the second-harmonic, indicating transport primarily by pairs of Cooper pairs. Finally, we demonstrate that noncollinear magnetization or spin-orbit coupling in the leads and the junction can lead to a gate-tunable Josephson diode effect with efficiencies of up to $\ensuremath{\sim}30%$.

EFEKTIVITAS MODEL PROBLEM BASED LEARNING BERBASIS ETNOMATEMATIKA DAYAK BENTIAN DITINJAU DARI KEMAMPUAN LITERASI MATEMATIKA DAN SELF-EFFICACY MAHASISWA PGSD

The transition of learning from the Covid-19 pandemic to the current new normal phase provides many changes that occur and must be made. In the educational aspect, it is necessary to re-develop the ability of students, namely literacy. In addition, it is necessary to develop a sense of self-efficacy as future teachers as well as learning that applies the problems of everyday life, especially Bentian Dayak culture (ethnomathematics) with a problem-based learning model. So this study aims to find out 1) what is the Bentian Dayak ethnomathematics-based problem-based learning model is effective in terms of the mathematical literacy skills of PGSD students and 2) what is the Bentian Dayak ethnomathematics-based problem-based learning model is effective in terms of the self-efficacy of PGSD students. The research was conducted experimentally using 1) One-Shot Case Study; and 2) One-Group Pretest-Posttest Design. Based on the results of the hypothesis test conducted, it shows that; 1) The learning model with ethnomathematics-based problem-based learning is not effective in terms of the mathematical literacy skills of PGSD students; 2) The learning model with ethnomathematics-based problem based learning is effective in terms of the self-efficacy of PGSD students

Ecosystem Services for the City as a Complex System: A Methodological Proposal

Originating from the main theories on the interpretation of the city as a system, this paper calls attention to the need to build a new theoretical framework. This framework would be able to support actions related to the consideration of ecosystem services in the activities governing urban and territorial transformations. By adopting the systemic interpretation of the city, it may be possible to more readily identify the ecosystem services related to each of the urban subsystems, and promote a new and different consideration of them when defining urban policies on the sustainable management of urban and territorial systems. This reflection describes a new approach to the problem, by indicating mainly the theoretical references and methodological connections to be considered in the development of a new dimension of territorial government. This dimension would be, by necessity, built upon issues that characterize the current historical phase, such as ecological transition, and the new potential of technological innovation that, if properly reconsidered, could contribute to substantially redefining the field of traditional urban planning.