Generator Replacement Research Articles

Cost Effectiveness of Deep Brain Stimulation for Parkinson's Disease: A Systematic Review.

Deep brain stimulation (DBS) is an established treatment for Parkinson's disease (PD) in patients with advanced motor symptoms with an inadequate response to pharmacotherapies. Despite its effectiveness, the cost effectiveness of DBS remains a subject of debate. This systematic review aims to update and synthesize evidence on the cost effectiveness of DBS for PD. To identify full economic evaluations that compared the cost effectiveness of DBS with other best medical treatments, a comprehensive search was conducted of the PubMed, Embase, Scopus, and Tufts Cost-Effective Analysis registry databases. The selected papers were systematically reviewed, and the results were summarized. For the quality appraisal, we used the modified economic evaluations bias checklist. The review protocol was a priori registered with PROSPERO, CRD42022345508. Sixteen identified cost-utility analyses that reported 19 comparisons on the use of DBS for PD were systematically reviewed. The studies were primarily conducted in high-income countries and employed Markov models. The costs considered were direct costs: surgical expenses, calibration, pulse generator replacement, and annual drug expenses. The majority of studies used country-specific thresholds. Fourteen comparisons from 12 studies reported on the cost effectiveness of DBS compared to best medical treatments. Eleven comparisons reported DBS as cost effective based on incremental cost-utility ratio results. The cost effectiveness of DBS for PD varies by time horizon, costs considered, threshold utilized, and stage of PD progression. Standardizing approaches and comparing DBS with other treatments are needed for future research on effective PD management.

A multioperator genetic algorithm for the traveling salesman problem with job-times

This paper addresses the traveling salesman problem with job-times (TSPJ). TSPJ considers two sets of equal size, a set of tasks and a set of vertices, where a traveler must visit each vertex exactly once, return to the starting vertex, and perform a unique task at each vertex. Each task is assigned to only one vertex, and each task is completed with a job-time that depends on each vertex. Thus, the objective is to minimize the time of the last task performed. However, due to its NP-hardness, existing algorithms do not optimally solve the TSPJ larger instances. Therefore, we propose an approach based on a multioperator genetic algorithm (MGA) that utilizes various initial population procedures, crossover and mutation operators. MGA applies five initial population procedures to generate a diverse population, and employs three crossover operators and six mutation operators, with four mutations focused on diversification and two designed to aid intensification. Furthermore, to improve the quality of the best individual found, a local search is used in every generation, and generational replacement with elitism is considered when generating a new population. MGA is evaluated on four sets of instances ranging in size from 17 to 1200 vertices: tsplib, small, medium, and large. Our approach outperforms the state-of-the-art algorithms on the four instance sets. This performance is attributed to the synergistic effect of the multioperators of crossover and mutation, along with effective parameter tuning.

Assessing the benefit of a replacement implantable cardioverter-defibrillator device for primary prevention of sudden cardiac death

Abstract Background Implantable cardioverter-defibrillators (ICDs) have been shown to reduce the burden of sudden cardiac death in at-risk populations. However, data reflecting contemporary device programming and medication would be valuable, particularly when evaluating patients for a replacement ICD when they did not receive therapy from their original device. Purpose This real-world analysis examined the incidence of ICD therapy after routine generator replacement due to battery depletion in patients who didn’t receive therapy from their first ICD. Methods Data were obtained from a query of a deidentified database from 2007 to present. The final analysis included patients that underwent a generator replacement after 2012 due to battery depletion and who had received no therapy from their first ICD. Patients were divided into two groups based on their ICD indication status (primary prevention [PP] or secondary prevention [SP]). The main endpoint was time to first appropriate shock therapy, antitachycardia pacing (ATP) therapy, or any therapy (ATP or shock) after ICD replacement. Time to first therapy was plotted using the Kaplan-Meier method. Appropriateness of therapy was modeled via LASSO regression using characteristics present in both our dataset and the adjudicated PainFree SST trial. The model was fit on episodes from 80% of PainFree SST patients and validated on the remaining 20% before applying it to our dataset. Results A total of 8,383 patients were identified who met the criteria outlined above. Of these patients, 7,299 (66.3 ± 12.6 years old; 30.3% female) had a PP indication for an ICD and 1,084 (64.2 ± 14.0 years old; 30.3% female) had an SP indication. The mean longevity of initial ICD implants before replacement was similar in PP and SP patients (91.4 ± 16.2 vs 90.9 ± 16.3 months). At 7 years post-replacement, the incidence of first shock, ATP, or any therapy received by PP patients who did not receive first-device therapy was 16%, 23% and 27% respectively. After applying the model to estimate appropriateness of therapy, the appropriate therapy rates were 14%, 22%, and 26%, respectively (Figure 1). Similarly, SP patients who received no first-device therapy had an incidence of modeled first appropriate shock, ATP, and any therapy 7 years after ICD replacement of 12%, 20%, and 25%, respectively. The modeled 7-year inappropriate shock rate post-replacement was 4% in all patients. Conclusion In this large, long-term, real-world evaluation of ICD PP patients who hadn’t experienced a treated event with their initial device, 1 in 4 eventually received appropriate therapy from their second device. The results suggest that the underlying risk persists in these patients and device replacement may be necessary to protect them from experiencing a deadly event.

Lead extraction of very old leads using the PISA technique - experience of a portuguese tertiary care center

Abstract Background The "Pisa Technique" (PT) is an increasingly used method of lead extraction (LE) that is associated with the lowest rate of complications reported in the ELECTRa Registry. Lead dwell time has been recognized as the highest risk factor for extraction failure and procedure-related complications. Purpose To investigate the safety and efficacy of LE, using the PISA technique, of very old cardiac implantable electronic devices (CIED) leads. Methods Patients submitted to LE of very old leads (with an implant duration of more than 10 years) between February 2013 and October 2022 (Old group), were compared with a contemporary cohort of patients subjected to LE of leads with a shorter implant duration (New group). The PT was used in all patients. Demographic, clinical, and patient-related variables, complications, mortality, and reimplantation data were assessed. Results A total of 150 very old leads were removed from 86 patients in the Old group, and a total of 305 leads were removed from 171 patients in the New group during the study period. Regarding the baseline characteristics, patient mean age was 69.5±16.9 years, 82.6% were male. Nine patients (10.5%) had cardiac resynchronization devices, 11 (12.8%) implantable cardioverter-defibrillator devices, and 66 (76.4%) pacemaker systems (mostly DDD). Of the total LE in the Old group, 88.4% were due to CIED infection (44.1% with valvular or lead endocarditis) vs 75.9% (p=0.464) vs the New group. The mean "age" of the extracted leads was 163.7±53.4 vs 46.6±34.9 months, and there were more of active fixation in the New group 35.2% vs 58.9%, p<0.01. A previous attempt of LE had been done in 5.8% vs 11.1% (p=0.172) of the patients, there were more previous generator replacements in the Old group 67.4% vs 23.7% (p<0.01). The radiographic success rate of the attempted lead extractions was similar between both groups 90.7% vs 96.5% (p=0.063). The clinical success rate was slightly lower in the Old group 95.3% vs 99.4% (p=0.031). The procedure major complications rate in the Old group was 2.3% (there were 2 cases of cardiac tamponade that required sternotomy with no laceration of the SVC observed) vs 1.2% (p=0.294) in the New group. Minor complications occurred in 11.6% vs 8.8% (p=0.466) of the LE (mostly comprised of infected pocket hematomas). No deaths occurred during the procedures, and there was no extraction-related mortality in both groups. Conclusion Our center’s experience with the PISA technique confirms the method’s safety and feasibility for the percutaneous extraction of very old CIED leads.

Cassandra speaks: a case series of unanticipated subcutaneous ICD premature battery depletion in a single-centre experience

Abstract Background Subcutaneous ICDs (S-ICD) are a valuable option in sudden cardiac death prevention. The main advantage over conventional transvenous ICDs is the absence of intravascular hardware for patients without the need for cardiac stimulation, resynchronization therapy or anti-tachycardia pacing. The claim of reduced lead-related complications has on the contrary been challenged by recent warnings of unexpected lead fracture. Moreover, concerns related to premature battery depletion (PBD) leading to unanticipated device replacement are increasing. Purpose To evaluate retrospectively the incidence of unanticipated S-ICD premature battery depletion in a single-centre experience. Method 168 consecutive patients implanted with S-ICD from February 2015 to November 2022 in our tertiary cardiology centre were included in this study. 4 patients moved to other sites and were thus lost to follow-up, leaving a total of 164 patients. PBD was defined as the occurrence of battery depletion requiring generator replacement earlier than 60 months post-implantation in the absence of therapy being delivered, or as a result of manufacturer recommendations. Results Most patients were implanted for primary prevention (101 patients, 60%). The main aetiology was hypertrophic cardiomyopathy (47 patients, 28%), followed by arrhythmogenic (35, 21%) and dilated idiopathic cardiomyopathy (24, 14%). Mean age and left ventricular ejection fraction at baseline were 46±18yrs and 51±16%, respectively. Over a total follow up period of 44±25 months, at 58±17 months following implantation 19 (11,6%) patients needed early replacement due to PBD, while 2 (1.2%) patients had lead fracture after respectively 41 and 26 months, for a total of 12,8% of patients with system-related complications. In addition to those patients requiring early replacement due to PBD or lead fracture, two underwent S-ICD extraction due to infection. Analysis of freedom from unanticipated PBD per year of implantation showed higher rates in years 2016 and 2017, with 67% and 27% of all implanted patients, respectively (Figure 1). Conclusions In this study, the incidence of PBDs appear to be higher than reported in literature though confined to a limited device series. However, if on the contrary the trend should remain remarkably high, that would not only endanger patients health due to repeated replacements, but also pose a huge economic burden to health systems.

Asynchronous generator replacement scheme with internal capacitive reactive power compensation

The relevance of using compensated induction machines in the generator mode of autonomous power supply systems is determined by their ability to provide a stable and reliable power supply even in the absence of an external grid. The research aims to develop a procedure for determining the characteristics of an equivalent circuit of compensated induction generators that considers the mutual influence between the main and additional phase windings of the armature. The theory of an idealised induction machine with the representation of electromechanical energy conversion processes and basic physical parameters in the form of equations of electrical equilibrium and drive motion was used to obtain the calculated characteristics of the generator’s operating modes of this class. The generalised system of differential equations made it possible to calculate dynamic and static processes for symmetrical and asymmetrical modes at given machine parameters under different methods of excitation and voltage stabilisation under variable load. For the practical implementation of modelling the parameters of an induction generator, the equations of electrical equilibrium of the stator and rotor circuits for the symmetrical steady-state mode are used, which is a special case of the generalised mathematical model of the machine for both transient and steady-state processes with constant parameters of the substitution scheme. Consideration of the structural and functional features of compensated induction generators was made possible by using a mathematical model with the armature winding divided into two coaxial or spatially offset half-windings. In this case, the number of calculation equations doubles. The use of an autotransformer scheme for switching on the stator phase half-windings to capacitors required the introduction of an additional differential equation for the electrical equilibrium of the stator phases. This made it possible to substantiate the values of active and inductive resistances used in the replacement circuit of an induction generator with internal capacitive reactive power compensation. The mutual inductive coupling of the main and additional half-windings of the generator stator phase windings due to both the operating magnetic flux and the magnetic fluxes of dissipation was considered. The practical significance of the obtained results is to increase the efficiency and stability of the power supply, which helps to reduce losses and improve the operation of electric power systems

Generational change in party support in Germany: The decline of the Volksparteien, the rise of the Greens, and the transformation of the education divide

Motivated by the eroding support for the old “Volksparteien” CDU/CSU and SPD, especially among younger voters, this study conducts an age-period-cohort analysis of vote choices in all 20 German federal elections, from 1949 to 2021. I study both generational differences in levels of party support and the changing effect of education on voting. The results, first, point to the importance of generational replacement in understanding party's shifting fortunes, with the CDU/CSU and the SPD being weaker in more recent cohorts and the Greens stronger. Second, while high education divides voters of the old right (CDU/CSU and especially FDP) and left (SPD) in earlier cohorts, it divides voters of the new-left Greens and the radical-right AfD in more recent cohorts. This study enhances our understanding of the changing patterns of party support in the German electorate and, as a broader lesson, shows how electoral realignment is driven by generational replacement.

Defibrillation testing of the subcutaneous implantable cardioverter-defibrillator at the time of generator replacement

Defibrillation testing of the subcutaneous implantable cardioverter-defibrillator at the time of generator replacement

Long-term energy transition planning: Integrating battery system degradation and replacement for sustainable power systems

The transition towards sustainable energy systems has gained significant importance globally due to high levels of environmental pollution caused by the use of fossil fuels. This study addresses a critical aspect of the global transition towards sustainable energy systems. We emphasize the impact of considering energy storage system degradation and replacement in long-term energy transition planning. The importance of this lies in mitigating the challenges posed by the intermittency and variability of renewable energy sources, such as wind and solar, without failing to consider the negative effect that excessive use of batteries as a storage energy system would have. We propose an optimization model that integrates power systems generation and transmission infrastructure with strategic energy storage system implementation to optimize their size, operation, and location for maximum efficiency and benefits. This paper offers a comprehensive approach to take into account the environmental effect of the depth of the discharge and replacement of battery systems over a long-term planning horizon considering hourly operation of representative time periods. The electricity system of Baja California, Mexico, a region heavily reliant on fossil fuels, is presented as a case study to show the applicability of the model. Results demonstrate that continuous replacement of dispatchable generators (natural gas power plants) for non-dispatchable generators (variable renewable power plants) may cause an unexpected increase of indirect greenhouse gas emissions from the continuous replacement of batteries when degradation is not considered. The results of the case study show an average emissions factor of 0.325 Ton CO2eq/MWh, approximately 24 % lower than government expectations, using the proposed MILP model.

Generational change in ceramic handicraft activity: Proposals for sustainable local and cultural development

The contribution refers to the generational change in the pottery handicraft activity of a rural community, the effect of this on the local and cultural development of the community, under a qualitative approach with application of the ethnographic method of interpretative character, applying techniques such as: life history, structured interview and observation. The information collected was processed in the software Atlas. Ti. The results show that young people have little knowledge about the process of making clay handicrafts, which is why they show little interest, since the knowledge has not been transmitted to them from an early age. In addition, the absence of schools or workshops that teach handicrafts aggravates the current situation. Traditions create a deep connection with roots, family and cultural values, which are necessary to persevere their identity and cultural heritage. The main activity to generate income is the production of handicrafts; however, the intermediaries that buy them do so at low cost, directly affecting the community. The problem lies in the lack of marketing channels, updated means of transportation and the absence of national and international web platforms to make the products visible. It is concluded that the deterioration in the generational replacement in the artisanal community over the years is attributed to the fact that young people do not perceive artisanal activity as a "business"; they choose to migrate to other cities, looking for new job offers and the possibility of obtaining professional training in other areas.

Length of hospital stay for elective electrophysiological procedures: a survey from the European Heart Rhythm Association.

Electrophysiological (EP) operations that have traditionally involved long hospital lengths of stay (LOS) are now being undertaken as day case procedures. The coronavirus disease-19 pandemic served as an impetus for many centres to shorten LOS for EP procedures. This survey explores LOS for elective EP procedures in the modern era. An online survey consisting of 27 multiple-choice questions was completed by 245 respondents from 35 countries. With respect to de novo cardiac implantable electronic device (CIED) implantations, day case procedures were reported for 79.5% of implantable loop recorders, 13.3% of pacemakers (PMs), 10.4% of implantable cardioverter defibrillators (ICDs), and 10.2% of cardiac resynchronization therapy (CRT) devices. With respect to CIED generator replacements, day case procedures were reported for 61.7% of PMs, 49.2% of ICDs, and 48.2% of CRT devices. With regard to ablations, day case procedures were reported for 5.7% of atrial fibrillation (AF) ablations, 10.7% of left-sided ablations, and 17.5% of right-sided ablations. A LOS ≥ 2 days for CIED implantation was reported for 47.7% of PM, 54.5% of ICDs, and 56.9% of CRT devices and for 54.5% of AF ablations, 42.2% of right-sided ablations, and 46.1% of left-sided ablations. Reimbursement (43-56%) and bed availability (20-47%) were reported to have no consistent impact on the organization of elective procedures. There is a wide variation in the LOS for elective EP procedures. The LOS for some procedures appears disproportionate to their complexity. Neither reimbursement nor bed availability consistently influenced LOS.

Postoperative infection problems in DBS applications

Deep brain stimulation (DBS) is a significant neuromodulation method for treating neurological and psychiatric disorders. Despite its efficacy, complications, particularly infections, are a concern. This article reviews the prevalence, risk factors, pathogens, infection locations, timing, surgical approaches, prevention strategies, and treatment methods associated with infections following DBS procedures. DBS surgeries have gained popularity due to their adjustability, but infections pose challenges. Surgical site infections (SSIs) are common (0% to 24% cases) and extensively studied regarding patient groups, locations, timing, and pathogens. Expanding patient groups, including conditions like Tourette syndrome and epilepsy, have varying infection risks. Infections occur at burr-hole, extension, and implantable pulse generator (IPG) sites. Staphylococcus aureus is a primary pathogen, yet bacterial DNA on IPGs and colonization complicate understanding. Surgical approaches, staged or non-staged, show comparable infection rates. The influence of repetitive pulse generator replacements on infection rates is debated. Lead externalization, topical vancomycin powder, and other factors impact infection risk. Treating DBS-related infections often requires hardware extraction and antibiotic treatment. Innovations like ethylene oxide sterilization and hydrogen peroxide show potential. Algorithms suggest partial explantation for localized infections. Cost analyses favor starting with antibiotics. Infections persist despite progress; understanding risks, pathogens, and strategies is vital for optimal outcomes in DBS.

Considerations involved in elective generator replacement of implantable cardioverter-defibrillators: balancing risks, benefits, and individual factors

Considerations involved in elective generator replacement of implantable cardioverter-defibrillators: balancing risks, benefits, and individual factors

Hydrogen production and utilization in oil and gas facilities

The transition to hydrogen as a cleaner energy carrier within oil and gas facilities presents a promising opportunity to reduce carbon emissions and promote sustainable energy practices. This review investigates the potential for hydrogen production and utilization in oil and gas operations, focusing on hydrogen-powered equipment and fuel cells as alternatives to conventional carbon-intensive technologies. The research explores the feasibility of integrating hydrogen into oil and gas processes, examining its role in decarbonizing operations through the replacement of diesel generators, compressors, and other machinery. Hydrogen production methods such as steam methane reforming (SMR) with carbon capture and storage (CCS) and electrolysis using renewable energy are analyzed to assess their viability in large-scale industrial applications. Additionally, the use of hydrogen fuel cells is explored as a means to provide reliable, low-emission energy for various on-site applications, including power generation, transportation, and heating. The review highlights both the technical and economic challenges associated with hydrogen adoption in oil and gas facilities, such as infrastructure development, hydrogen storage, and distribution. However, it also emphasizes the long-term benefits, including reduced greenhouse gas emissions, compliance with global environmental regulations, and improved operational efficiency. By investigating hydrogen’s role as a cleaner energy carrier, this research contributes to the ongoing discourse on transitioning the oil and gas industry towards more sustainable and environmentally friendly practices.

One-Year Mortality in Patients Undergoing an Implantable Cardioverter Defibrillator or Cardiac Resynchronization Therapy Pulse Generator Replacement: Identifying Patients at Risk.

Implantable cardioverter defibrillators (ICDs) significantly contribute to the prevention of sudden cardiac death in selected patients. However, it is essential to identify those who are likely to not have benefit from an ICD and to defer a pulse generator exchange. Easily implementable guidelines for individual risk stratification and decision making are lacking. This study investigates the 1-year mortality of patients who underwent an ICD or cardiac resynchronization therapy with defibrillator function (CRT-D) pulse generator replacement in a contemporary real-world tertiary hospital setting. The cause of death and patient- and procedure-related factors are stratified, and predictive values for 1-year mortality are evaluated. Patients with a follow-up of ≥365 days (or prior mortality) after an ICD or CRT-D exchange at the Leiden University Medical Center from 1 January 2018 until 31 December 2021 were eligible. In total, 588 patients were included (77% male, 69 [60-76] years old, 59% primary prevention, 46% ischemic cardiomyopathy and 37% mildly reduced left ventricular ejection fraction (LVEF)). Patients undergoing a CRT-D replacement or upgrade had a significantly higher 1-year all-cause mortality (10.7% and 11.9%, respectively) compared to patients undergoing ICD (2.8%) exchange (p = 0.002). LVEF ≤ 30%, New York Heart Association class ≥ 3, estimated glomerular filtration rate ≤ 30 mL/min/m2 and haemoglobin ≤ 7 mmol/L were independently associated with mortality within 1 year after pulse generator replacement. There is a growing need for prospectively validated risk scores to weight individualized risk of mortality with the expected ICD therapy benefit and to support a well-informed, shared decision-making process.

Power Angle–Frequency Droop Control to Enhance Transient Stability of Grid-Forming Inverters Under Voltage Dips

Due to the replacement of synchronous generators, grid operators are currently demanding to control grid-connected inverters in grid&#x2013;forming mode to make them participate in the maintenance of the grid. To carry this out, the traditional droop controls based on the active and reactive powers are usually adopted, achieving a satisfactory performance in normal operation. Nevertheless, the power-frequency (<i>P</i>-&#x03C9;) droop may become transiently unstable under voltage dips. This is because of the modification of the active power response caused by the inverter current limitation together with the voltage reduction. To enhance this, the power angle-frequency (&#x03B4;_inv-&#x03C9;) droop is proposed, consisting in employing an estimation of the inverter power angle as input to obtain the inverter frequency. The proposed method provides the inverter with the same performance as the <i>P</i>-&#x03C9; droop in normal operation, while enhancing considerably the transient stability margins under current limitation. This is thanks to the higher variation of the inverter power angle with the phase difference between the inverter and the grid. Simulation results show the transient stability problems of the <i>P</i>-&#x03C9; droop as well as the superior performance of the proposed &#x03B4;_inv-&#x03C9; droop control, which has also been verified by means of HIL results.

Inertia estimation of multi-area power systems using tie-line measurements and modal sensitivity analysis

The replacement of conventional synchronous generators with converter-interfaced renewable energy sources (RESs) reduces the overall inertia levels of modern power systems, leading to frequency stability issues. Moreover, the intermittent nature of RESs constitutes system inertia variable during the day, further complicating the frequency control procedure. Therefore, power system operators shall estimate close to real-time the overall inertia levels of their grids in order to ensure their secure and reliable operation. In this context, in this paper, a new methodology for the inertia estimation of multi-area power systems is formulated. The proposed method uses the modal sensitivity matrix to obtain a linear approximation of the relation between modal parameters and inertia constants. During the real-time operation, modal parameters are identified via system responses using the Matrix Pencil method. The identified modes and the derived sensitivity matrix are used to estimate the overall inertia of the examined power system. The effectiveness of the proposed method is validated by means of simulations performed in one-area, two-area, and three-area power system models.

Community microgrid planning in Lombok Island: an Indonesian case study

Rural electrification, diesel generator replacement, and resilient electrification systems against natural disasters are among the main targets for Perusahaan Listrik Negara (PLN) in Indonesia to achieve a universally accessible, resilient, and environment-friendly electricity supply. Microgrids, therefore, become a popular and available way to achieve the aforementioned targets due to their flexibility and resiliency. This paper aims to provide a resilience-oriented planning strategy for community microgrids in Lombok Island, Indonesia. A mixed-integer linear program, implemented in the distributed energy resources customer adoption model (DER-CAM), is presented in this paper to find the optimal technology portfolio, placement, capacity, and optimal dispatch in a community microgrid. The multinode model is adopted for the planning, and hence, power flow constraints, N-1 contingency, and technology constraints are considered. The results show that the placement of photovoltaic (PV) arrays, battery energy storage systems (BESSs), and diesel generators (DGs) as backup sources in multi-node community microgrids lead to multiple benefits, including 100% rural electrification, over 25% cost savings, as well as over 22%, in particular CO2 emission reduction in multinode community microgrids.

Enhancing the wind farm‐based power system stability with coordinated tuned supplementary controller

SummaryThe effects of the wind farm on the low‐frequency oscillations of interconnected power systems have become a significant problem with extensive apprehension. These low‐frequency oscillations are undesirable, malfunctioning and resulting in system instability. This paper studies the influence of various factors on stability, with varying wind penetration, a different combination of controllers, wind farm (WF) integration and replacement of synchronous generators. To enhance the stability, it is integrated and analyzed significance of the controller by considering the power oscillation damper for WF, power system stabilizer for synchronous generators and supplementary controller of flexible AC transmission system devices for the system. The rotor speed deviation is considered an objective function with various constraints for particle swarm optimization to provide the controller's optimized value and combination. The small‐signal and transient stability problems were examined using eigenvalue analysis and time‐domain simulation. The state‐space formulation is derived for eigenvalue analysis for small signal stability assessment with system variables. The nonlinear dynamic simulation results for transient stability analysis are obtained using a three‐phase fault. From stability analysis, coordinated controllers intensify the capability of SGs and WF under extreme disturbances. The effectiveness and robustness of the proposed approaches have been verified using the IEEE‐9 bus test system. All the analysis and simulations are performed using real time digital simulation (RTDS) with interfacing between MATLAB/SIMULINK‐2018a software and RT‐LAB (an OP5600 RT‐LAB).

Another path to electoral reform: Cohort replacement and electoral issues for rule changes in Japan

AbstractThe literature of electoral reform explains politicians' preferences and social forces such as working‐class power or expansions of the suffrage are the major factors that bring about a change in electoral rules. However, we argue that generational replacement and electoral issue effects lead politicians to introduce a new electoral system for their electoral survival in future. By examining Japan's surveys for pre‐ and postreform elections, we show that the entrance of new generation and salient issue concerns dissolve electoral bases of political parties and finally give rise to a change in the rules of the game for the greater electoral stability that political elites desire.