Shortest Path Routing Research Articles

Perceived Negative Menstrual Cycle Symptoms, but not Changes in Estrogen or Progesterone, are Associated with Impaired Cycling Race Performance.

Purpose: To examine the relationship between menstrual cycle (MC) phase-dependent fluctuations of estrogen and progesterone and virtual cycling race performance, with a secondary aim of correlating perceived MC-related symptoms with performance.Methods: In a novel observational study design, thirty-seven female cyclists/triathletes not using any hormonal contraception completed one virtual cycling race [19.5 km time trial (TT)] per week across a one-month period (totaling four races). Participants completed MC characterization and tracking, including urinary ovulation kits, across two complete MCs. Venous blood samples were collected within 21 h of racing to determine serum 17-β-estradiol and progesterone concentrations, as well as an assessment of self-reported, perceived race-day MC and gastrointestinal (GI) symptoms, which were all then correlated to race performance.Results: There was no relationship between race completion time and individual estradiol (r = -0.001, p = 0.992) or progesterone (r = -0.023, p = 0.833) concentrations. There was no difference between race time between MC phases (follicular/luteal, p = 0.238), whether MC bleeding or not bleeding (p = 0.619) and ovulating or not ovulating (p = 0.423). The total number of perceived MC symptoms recorded on race day was positively correlated to increased race time [r = 0.268 (95% CI 0.056 to 0.457), p = 0.014], as was the number of GI symptoms of at least "moderate" severity before the race (r = 0.233 [95% CI 0.021 to 0.425], p = 0.031), but not post-race (r = 0.022, p = 0.841).Conclusions: When implementing a novel, virtual cycling race, fluctuations in ovarian hormone concentrations across the MC do not appear to affect real-world cycling performance among trained cyclists, while perceived negative MC and GI symptoms may relate to impaired performance. Therefore, the management of negative MC and GI symptoms appears important for athletic performance enhancement or to mitigate performance decline.

The hidden cost of abusive supervision: rudeness, sabotage, and ethics.

Abusive supervision in healthcare settings can have detrimental effects on employee behavior and patient care, making it crucial to understand the underlying mechanisms and mitigating factors. This study examines the impact of abusive supervision on patient-directed service sabotage, focusing on the mediating role of workplace rudeness and the moderating effect of work ethics. Data were collected from 305 hospital nurses, and structural equation modeling (SEM) was used to test the proposed model. The findings reveal that abusive supervision significantly increases workplace rudeness, which in turn escalates to service sabotage. However, strong work ethics were found to weaken the link between rudeness and sabotage, demonstrating their protective role in this negative cycle. The moderated mediation analysis further confirms that work ethics reduce the indirect impact of abusive supervision on service sabotage through rudeness. These results contribute to our understanding by illustrating how ethical standards can buffer against the negative consequences of abusive supervision, providing practical implications for enhancing leadership practices and promoting ethical behavior in healthcare environments.

DFRDRL: a dynamic fuzzy routing algorithm based on deep reinforcement learning with guaranteed latency and bandwidth for software-defined networks

Traditional routing algorithms have several limitations that become increasingly significant in the context of Software-Defined Networking (SDN). Firstly, these algorithms often have limited support for Quality of Service (QoS) requirements, making them less suitable for handling diverse traffic types efficiently. Moreover, current SDN controllers leverage a default shortest-path routing approach, which does not allow for more dynamic and flexible traffic management based on real-time network policies. To address these issues, this paper introduces a Dynamic Fuzzy Routing algorithm based on Deep Reinforcement Learning (DRL) for SDN that provides guaranteed latency and bandwidth (DFRDRL). DFRDRL provides intelligent and efficient routing that adapts to dynamic traffic by considering path-state criteria and using DRL. Fuzzy logic mainly performs online routing between an ingress-egress pair. To adapt to dynamic traffic changes, DFRDRL can predict the traffic matrix in real time. Meanwhile, DFRDRL reduces the routing reliance on network topology by weighting the network based on critical nodes. Additionally, when the network experiences congestion based on the traffic matrix, a deferral mechanism is applied to prioritize requests with lower resource demands. This mechanism helps ensure efficient resource allocation by temporarily postponing or queuing higher-demand requests, thereby optimizing overall network performance during periods of congestion. The simulation results show that the performance of DFRDRL is better than the equivalent algorithms in terms of latency and throughput. Also, DFRDRL is about 2.5% more efficient than the best existing algorithm in terms of admission rate of routing requests.

The effect of multi-step cycles on the surface properties of Ni-TiO2 coatings produced by pulse current electrodeposition

ABSTRACT In this study, the Ni-TiO2 coatings were deposited on copper substrates by pulse plating. The effect of multi-step current cycles on the metallurgical properties of produced coatings was investigated. The results showed that the values of applied currents within the periods significantly affect the surface properties of all coatings. Using the negative current cycles, the surface morphologies completely changed from regular and compact to irregular, compared to the deposits that did not have a negative cycle in the coating process. Also, the surface roughness increased by 1.5 times in the best case. Applying the 8-step cycle increased the percentage of TiO2 content inside the Ni-TiO2 layer from 13.13 vol.% to 31.58%. The corrosion and wear analysis results showed that the coating applied by a 4-step cycle with a 90-second off time has the best properties. Therefore, the corrosion and wear properties were not necessarily directly related to the participation percentage of TiO2 particles. Compact morphology with high current efficiency, wide distribution of TiO2 particles (6.31 vol.%) with minimal agglomeration, low coating roughness (Ra = 0.32 µm), high hardness value (436 Vickers), and the participation of (111) plane in the preferred texture improved the corrosion and wear behaviour of the optimal coating.

Smart forest monitoring: A novel Internet of Things framework with shortest path routing for sustainable environmental management

AbstractForests play a pivotal role in protecting the environment, preserving vital natural resources, and ultimately sustaining human life. However, the escalating occurrences of forest fires, whether of human origin or due to climate change, poses a significant threat to this ecosystem. In recent decades, the emergence of the IoT has been characterised by the utilisation of smart sensors for real‐time data collection. IoT facilitates proactive decision‐making for forest monitoring, control, and protection through advanced data analysis techniques, including AI algorithms. This research study presents a comprehensive approach to deploying a dynamic and adaptable network topology in forest environments, aimed at optimising data transmission and enhancing system reliability. Three distinct topologies are proposed in this research study: direct transmission from nodes to gateways, cluster formation with multi‐step data transmission, and clustering with data relayed by cluster heads. A key innovation is the use of high‐powered telecommunication modules in cluster heads, enabling long‐range data transmission while considering energy efficiency through solar power. To enhance system reliability, this study incorporates a reserve routing mechanism to mitigate the impact of node or cluster head failures. Additionally, the placement of gateway nodes is optimised using meta‐heuristic algorithms, including particle swarm optimisation (PSO), harmony search algorithm (HSA), and ant colony optimisation for continuous domains (ACOR), with ACOR emerging as the most effective. The primary objective of this article is to reduce power consumption, alleviate network traffic, and decrease nodes' interdependence, while also considering reliability coefficients and error tolerance as additional considerations. As shown in the results, the proposed methods effectively reduce network traffic, optimise routing, and ensure robust performance across various environmental conditions, highlighting the importance of these tailored topologies in enhancing energy efficiency, data accuracy, and network reliability in forest monitoring applications.

Impact of piezoelectric driving waveform on performance characteristics of vibrating mesh atomizer (VMA)

Vibrating mesh atomizer (VMA) is a specific type of ultrasonic atomizer known for its low power consumption and production of uniformly fine droplets. While previous research has provided a basic understanding of VMA operation, it has primarily focused on driving the piezoelectric actuator with continuous and symmetrical waveforms, such as sine and square waveforms. This study aims to experimentally investigate the impact of different driving waveforms on the ultrasonic atomization process and the associated performance characteristics. Specifically, the effects of pulse waveforms (Gauss and Lorentz pulse) were analyzed with high rates of energy deposition and asymmetrical hybrid waveforms (trapezia and absolute sine), featuring distinct negative cycles, by comparing them with conventional symmetrical waveforms (sine and square). Pulse waveforms suppress the growing stage but provide a high flux of input energy, facilitating the detachment of liquid into fine droplets, resulting in uniformly distributed droplets with VMDs of 5.84 μm and 4.71 μm for Gauss and Lorentz waveforms, respectively. Conversely, shorter negative cycles in asymmetrical hybrid waveforms reduce liquid suction into the micronozzle, leading to higher energy flux during subsequent positive cycles that promote the growing stage, producing larger droplets with VMDs of 10.82 μm and 11.86 μm for trapezia and absolute (abs) sine waveforms, respectively. Additionally, high-speed imaging reveals irregular pulsating behaviors in the atomization process when using pulse waveforms, suggesting a reciprocating-pump-like operation mechanism in VMA atomization. These new insights contribute to an improved understanding of the atomization mechanism in VMAs.

Negative cell cycle regulation by calcineurin is necessary for proper beta cell regeneration in zebrafish.

Stimulation of pancreatic beta cell regeneration could be a therapeutic lead to treat diabetes. Unlike humans, the zebrafish can efficiently regenerate beta cells, notably from ductal pancreatic progenitors. To gain insight into the molecular pathways involved in this process, we established the transcriptomic profile of the ductal cells after beta cell ablation in the adult zebrafish. These data highlighted the protein phosphatase calcineurin (CaN) as a new potential modulator of beta cell regeneration. We showed that CaN overexpression abolished the regenerative response, leading to glycemia dysregulation. On the opposite, CaN inhibition increased ductal cell proliferation and subsequent beta cell regeneration. Interestingly, the enhanced proliferation of the progenitors was paradoxically coupled with their exhaustion. This suggests that the proliferating progenitors are next entering in differentiation. CaN appears as a guardian which prevents an excessive progenitor proliferation to preserve the pool of progenitors. Altogether, our findings reveal CaN as a key player in the balance between proliferation and differentiation to enable a proper beta cell regeneration.

Negative cell cycle regulation by calcineurin is necessary for proper beta cell regeneration in zebrafish

Stimulation of pancreatic beta cell regeneration could be a therapeutic lead to treat diabetes. Unlike humans, the zebrafish can efficiently regenerate beta cells, notably from ductal pancreatic progenitors. To gain insight into the molecular pathways involved in this process, we established the transcriptomic profile of the ductal cells after beta cell ablation in the adult zebrafish. These data highlighted the protein phosphatase calcineurin (CaN) as a new potential modulator of beta cell regeneration. We showed that CaN overexpression abolished the regenerative response, leading to glycemia dysregulation. On the opposite, CaN inhibition increased ductal cell proliferation and subsequent beta cell regeneration. Interestingly, the enhanced proliferation of the progenitors was paradoxically coupled with their exhaustion. This suggests that the proliferating progenitors are next entering in differentiation. CaN appears as a guardian which prevents an excessive progenitor proliferation to preserve the pool of progenitors. Altogether, our findings reveal CaN as a key player in the balance between proliferation and differentiation to enable a proper beta cell regeneration.

High-speed multi-stage gas-steam turbine with flow bleeding in a novel thermodynamic cycle for decarbonizing power generation

In the global pursuit of sustainable energy and reduced carbon footprints, advances in power generation techniques play a crucial role, not only in meeting the ever-increasing energy demands but also in ensuring that environmental standards are maintained and that the health of our planet is prioritized for future generations.In the ongoing quest for sustainable energy solutions, novel high-speed multi-stage gas-steam turbine models were designed to address the challenge of decarbonized power production. The thermodynamic parameters were adopted on the basis of the negative carbon dioxide gas power plant cycle relying on the following main devices, namely: wet combustion chamber, spray-ejector condenser, sewage sludge gasifier and gas-steam turbine. The peculiarities of the present system make the turbine the link of three important devices and its parameters affect the entire thermodynamic cycle. Therefore, it is reasonable to carry out dedicated novel in literature CFD calculations that also take into account the bleeding of the medium for the gasification process.Two distinct turbine models were introduced: a two-stage turbine achieving speeds of 95 000 rpm with an efficiency of more than 80%, and a five-stage turbine reaching 40 000 rpm with an efficiency of less than 70%. A design assumption of a bleed pressure of 100 kPa and a mass flow rate of 0.1 kg/s was adopted for both models. Computational simulations were utilized, and the turbine stages were selected with the aim of reducing energy losses. Through this work, a significant step towards a carbon-negative future using high-speed turbine technologies was demonstrated, laying the groundwork for further advancements in the field.

“Try until the last?”—the relevance of fresh embryo transfer outcomes for subsequent same-cohort vitrified–warmed cycles

PurposeTaking into consideration earlier attempts at assisted reproduction and previous pregnancies allows a more differentiated approach when counseling couples regarding their chances in assisted reproductive treatments. The aim of this study was to investigate whether the outcome of fresh embryo transfers affects subsequent same-cohort vitrified–warmed cycles.MethodsThis retrospective cohort study analyzes the outcome of all fresh and frozen embryo transfers (n = 8118) between January 1, 2011, and December 31, 2022. All women who received fresh or frozen embryo transfers at Kepler University Hospital Linz were included. The use of donor eggs, previously cryopreserved oocytes, and freeze-all cycles were excluded from the analysis.ResultsPositive serum βhCG after a fresh cycle has a significant impact on the chances of positive βhCG in a subsequent vitrified–warmed cycle (36.3% [33.2%, 39.5%]; P = 0.002). Negative βhCG after a fresh cycle does not predict the outcome of the following same-cohort embryo transfer (33.1% [30.7%, 35.7%], P = 0.726). Pregnancy rates of the first, second, third, and fourth same-cohort vitrified–warmed embryo transfer remain continuously high, with 32.8%, 30.8%, 28.9%, and 27.1%, respectively.ConclusionsPositive serum βhCG after a fresh embryo transfer has a positive predictive value for the outcome of a subsequent vitrified–warmed embryo transfer. Couples with a negative fresh cycle should not be discouraged from continuing fertility treatment using same-cohort frozen embryos.Trial registrationThis study was prospectively registered at the German Clinical Trials Register on September 5, 2023 (DRKS00032552).

A systematic review and meta-analysis of the parental stress scale's psychometric properties.

Parental stress can affect the ability of parents to cope with the challenges of raising children. The result can be a negative cycle within the family dynamic, which in turn can interfere with children's development and emotional regulation. Among the many instruments available to assess parental stress, the Parental Stress Scale (PSS) deserves particular mention. To our knowledge, there are currently no systematic reviews evaluating the psychometric properties of the PSS. The aim of this systematic review was to assess the psychometric properties of the PSS using the COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) methodology and to conduct a meta-analysis. A thorough literature search was conducted from different databases. A meta-analysis to test the generalisability of PSS internal consistency across its component factors was performed. A total of 20 validation studies of the PSS were identified. Based on the COSMIN methodology, this instrument receives an 'A' rating, meaning that it is considered to be a cross-sectional instrument with the necessary scientific evidence for the assessment of the construct of parental stress. The meta-analysis testing the generalisability of its internal consistency yielded satisfactory results across the different factors. Future research should focus on those psychometric properties of the PSS that have not been studied as extensively, such as reproducibility, responsiveness, measurement error, and measurement invariance.

Disability and infidelity with a cross-cultural couple: an emotionally focused therapy case study

ABSTRACT This clinical case study delves into the therapeutic process of a cross-cultural couple, facing the intersection of disability and infidelity concerns. This intersection illuminates the intricate dynamics that arise when couples navigate both the complexities of disability and the emotional turmoil associated with infidelity. Utilizing Emotionally Focused Therapy (EFT), case intervention unfolded through three distinct stages, revealing intricate emotional dynamics, attachment styles, and communication patterns. The study explores the couples’ narrative, negative interaction cycles, and distinct emotional processing styles, considering complicating factors such as immigration challenges, cultural norms, and online infidelity. To strengthen bonds, the therapeutic approach promotes cultural sensitivity, intersectionality, and emotional connection. Despite time constraints and visa issues, the study highlights the efficacy of EFT in navigating the complexities of this cross-cultural couple. This case study contributes to the existing literature by examining the interplay of disability, infidelity, and cultural diversity within the framework of couples’ therapy.

A Biomass-based Carbon Negative Brayton-Rankine Coupled Cycle Employing MCFC, Gasification and Combustion Boiler

Biomass based plants with CO2 capture usually experience low efficiency, at the same time, have great potential of mitigating environmental damage due to climate change. In this work, unlike conventional power plants, a novel biomass-based carbon negative power plant has been conceived considering both biomass gasification and a biomass combustion boiler. CO2 capture and improved efficiency due to the unique integration of the plant components are the major expected outcome from the proposed plant model. The plant contains a steam cycle, an MCFC and an EFGT unit as the power producing blocks. A vital operating parameter i.e., biomass combustion boiler equivalence ratio () has been varied to witness the changes in performance of the plant. The net power generated by the plant seemed to be increasing with . The plant performs best when the plant is operated at a  value of 2.5. At this operating condition, the net power generated by the power plant found to be 13796 kW with 75.52 % efficiency and 0.3957 kg/kWh specific biomass consumption (SBC).

Cervix-Deep Rectal Temperature Differential on the Day ofOvulation is Correlated With Embryo Recovery Results in Mares.

Variations in temperature throughout the reproductive tract have been noted in many species. A recent study found the cervix-rectum temperature differential (CR-TD) in cattle was related to fertility. The present study aimed to assess the CR-TD in mares around the time of ovulation and relate it to embryo recover. Over 52 cycles, mares were inseminated with a fertile stallion and embryo recovery was undertaken on Day 7 post ovulation. Further 10 control mares were not inseminated. Rectal and cervical temperatures were measured using a precision thermometer on four or five occasions: the day of deslorelin administration and insemination, the day before ovulation, the day of ovulation (Day 0), the day after ovulation and, for inseminated mares, before embryo recovery on Day 7. One-way ANOVA showed that the CR-TD was significantly lower on the day of ovulation in the 36 positive cycles, in which an embryo was recovered, versus the 16 in which the embryo flush was negative (0.21 ± 0.17 vs. 0.40 ± 0.09°C; p < 0.001). Control cycles showed equivalent CR-TD to positive (0.13 ± 0.22 vs. 0.21 ± 0.17°C; p = 0.196) but not negative cycles (0.13 ± 0.22 vs. 0.40 ± 0.09°C; p < 0.001). A positive embryo recovery was associated with lower CR-TDs from the time of insemination and deslorelin to the day after ovulation compared to the day of embryo flushing (RM ANOVA; p < 0.001; Pairwise comparisons; p ≤ 0.01, in all cases). Rectal or cervical temperatures per se showed no significant differences between positive, negative or control cycles at any time point. In conclusion, a thermoregulatory process occurs close to ovulation which results in a lower CR-TD in cycles that produced an embryo versus those which did not. Further characterisation of TDs within the reproductive tract of the mare would increase our understanding of the conditions required for optimum fertility.

Proactive deadlock prevention based on traffic classification sub-graphs for triplet-based NoC TriBA-cNoC

Network topology and routing algorithms stand as pivotal decision points that profoundly impact the performance of Network-on-Chip (NoC) systems. As core counts rise, so does the inherent competition for shared resources, spotlighting the critical need for meticulously designed routing algorithms that circumvent deadlocks to ensure optimal network efficiency. This research capitalizes on the Triplet-Base Architecture (TriBA) and its Distributed Minimal Routing Algorithm (DM4T) to overcome the limitations of previous approaches. While DM4T exhibits performance advantages over previous routing algorithms, its deterministic nature and potential for circular dependencies during routing can lead to deadlocks and congestion. Therefore, this work addresses these vulnerabilities while leveraging the performance benefits of TriBA and DM4T. This work introduces a novel approach that merges a proactive deadlock prevention mechanism with Intermediate Adjacent Shortest Path Routing (IASPR). This combination guarantees both deadlock-free and livelock-free routing, ensuring reliable communication within the network. The key to this integration lies in a flow model-based data transfer categorization technique. This technique prevents the formation of circular dependencies. Additionally, it reduces redundant distance calculations during the routing process. By addressing these challenges, the proposed approach achieves improvements in both routing latency and throughput. To rigorously assess the performance of TriBA network topologies under varying configurations, extensive simulations were undertaken. The investigation encompassed both TriBA networks comprising 9 nodes and those with 27 nodes, employing DM4T, IASPR routing algorithms, and the proactive deadlock prevention method. The gem5 simulator, operating under the Garnet 3.0 network model using a standalone protocol for synthetic traffic patterns, was utilized for simulations at high injection rates, spanning diverse synthetic traffic patterns and PARSEC benchmark suite applications. Simulations rigorously quantified the effectiveness of the proposed approach, revealing reductions in average latency 40.17% and 34.05% compared to the lookup table and DM4T, respectively. Additionally, there were notable increases in average throughput of 7.48% and 5.66%.

GPU-accelerated parallel all-pair shortest path routing within stochastic road networks

All-pair shortest path routing within stochastic road networks is often more complicated and computationally challenging than routing in deterministic networks because uncertainties in travel time are introduced. We develop and test a GPU-enabled approach to resolve this computational challenge. This approach is based on a simulation framework that includes four steps: simulation of road networks impedances, computation of candidate paths using an all-pair shortest path algorithm, travel time estimation across candidate paths, and all-pair optimal path calculations. We developed GPU algorithms to accelerate the second and third steps, which are computationally demanding for large road networks. We used the road network of Wuhan, China as a case study. Our experiments indicate that the GPU approach leads to thousands of times in improvement of acceleration, which makes all-pair shortest path routing within stochastic road networks computationally feasible.

Investigation of Partial Discharge Transformation Characteristics in Polyimide (PI) Insulations under High-Frequency Electric Stress.

This research delves into the primary issue of polyimide (PI) insulation failures in high-frequency power transformers (HFPTs) by scrutinizing partial discharge development under high-frequency electrical stress. This study employs an experimental approach coupled with a plasma simulation model for a ball-sphere electrode structure. The simulation model integrates the particle transport equation, Poisson equation, and complex chemical reactions to ascertain microscopic parameters, including plasma distribution, electric field, electron density, electron temperature, surface, and space charge distribution. The effect of the voltage polarity and electrical energy on the PD process is also discussed. The contact point plays a pivotal role in triggering partial discharges and culminating in the breakdown of PI insulation. Asymmetry phenomena were found between positive and negative half-cycles by analyzing the PD data stage by stage. A significant number of PDs increased at every stage and the PD amplitude was higher during the negative cycle at the initial stage, but in later stages, the PD amplitude was found to be higher in the positive half-cycle, and scanning electron microscopy (SEM) revealed that the maximum damage occurred near the contact point junction. The simulation results show that the plasma initially accumulates the electron density near the contact point junction. Under the action of the electric field, plasma starts traveling at the PI surface outward from the contact point. Before the PD activity, all parameters have higher values in the plasma head. The microscopic parameters reveal maximum values near the contact point junction, during PD activities where significant damage takes place. These parameter distributions exhibit a decreasing trend over time as when the PD activity ends. The model's predictions are consistent with the experimental data. The paper lays the foundation for future research in polymer insulation design under high-frequency electrical stress.

Elucidation of discharge mechanisms in He- and Ar-flexible μ-tube plasmas by temporally and spatially resolved plasma optical emission phoresis spectroscopy

A Helium- and Argon-flexible μ-tube plasma (FμTP) driven by a square wave high voltage were investigated by means of temporally and spatially resolved spectroscopy to characterize the discharge mechanisms. These two discharge gases show different discharge behavior in the same FμTP-configuration. The mixtures of different concentration of propane in Ar were used as discharge gases to confirm the role of Ar+ in an Ar-FμTP by tuning the discharge behavior. It was demonstrated that, N2+ are mainly responsible for the excitation and ionization and only small amount of He+ are produced in a He-FμTP, whereas Ar-FμTP lives from Ar+. These ions as well as excited species do not propagate beyond the capillary during the negative half cycle, resulting in a negligible contribution for protonation in this half cycle. The present study proposes a new method to data analysis, Plasma Optical Emission Phoresis Spectroscopy, which allows to distinguish noble gas ions from excited noble gas species.

NxtSPR: A deadlock-free shortest path routing dedicated to relaying for Triplet-Based many-core Architecture

Deadlock-free routing is a significant challenge in Network-on-Chip (NoC) design as it affects the network’s latency, power consumption, and load balance, impacting the performance of multi-processor systems-on-chip. However, achieving deadlock-free routing will routinely result in expensive overhead as previous solutions either sacrifice performance or power efficiency to proactively avoid deadlocks or impose high hardware complexity to resolve deadlocks when they occur reactively. Utilizing the various characteristics of NoC to implement deadlock-free routing can be significantly more cost-effective with less impact on performance. This paper proposes a relay routing algorithm (NxtSPR) with a shortest path property and a deadlock prevention mechanism based on a synchronized Hamiltonian ring. The proposal is based on an in-depth study of the characteristics of a Triplet-Based many-core Architecture (TriBA) NoC. We establish various important topology-related theories and perform a formal verification (proof-based) for them. By utilizing the critical subgraph and apex of TriBA, NxtSPR can pre-calculate downstream nodes forwarding ports for packets by using a concise judgment strategy. This significantly reduces the computational overhead required for data transmission while optimizing the pipeline design of routers to decrease packet transmission latency and power consumption compared to other TriBA routing algorithms. We group the data transmissions according to the levels of maximum Hamiltonian edges a packet will traverse during its transmission life cycle. Independent data transmissions between groups can avoid mutual interference and resource competition, eliminating potential deadlocks. Gem5 simulation results show that, under the synthetic traffic patterns, compared to the representative (Table) and up-to-date (SPR4T) routing algorithms, NxtSPR achieves a 20.19%, 14.76%, and 5.54%, 4.66% reduction in average packet latency and per-packet power consumption, respectively. Moreover, it has an average of 18.50% and 4.34% improvement in throughput, as compared to them. PARSEC benchmark results show that NxtSPR reduces application runtime by up to a maximum of 22.30% and 12.82% compared to Table and SPR4T, and running the same applications with TriBA results in a maximum runtime reduction of 10.77% compared to 2D-Mesh.

Design and implementation of an innovative single-phase direct AC-AC bipolar voltage buck converter with enhanced control topology

Direct AC–AC converters are strong candidates in the power converting system to regulate grid voltage against the perturbation in the line voltage and to acquire frequency regulation at discrete step levels in variable speed drivers for industrial systems. All such applications require the inverted and non-inverted form of the input voltage across the output with voltage-regulating capabilities. The required value of the output frequency is gained with the proper arrangement of the number of positive and negative pulses of the input voltage across the output terminals. The period of each such pulse for low-frequency operation is almost the same as the half period of the input grid or utility voltage. These output pulses are generated by converting the positive and negative input half cycles in noninverting and inverting forms as per requirement. There is no control complication to generate control signals used to adjust the load frequency as the operating period of the switching devices is normally greater than the period of the source voltage. However, high-frequency pulse width modulated (PWM) control signals are used to regulate the output voltage. The size of the inductor and capacitor is inversely related to the value of the switching frequency. Similarly, the ripple contents of voltage and currents in these filtering components are also inversely linked with PWM frequency. These constraints motivate the circuit designer to select high PWM frequency. However, the alignment of the high-frequency control input with the variation in the input source voltage is a big challenge for a design engineer as the switching period of a high-frequency signal normally lies in the microsecond. It is also required to operate some high-frequency devices for various half cycles of the source voltage, creating control complications as the polarities of the half cycles are continuously changing. This requires at least the generation of two high-frequency signals for different intervals. The interruption of the filtering inductor current is a big source of high voltage surges in circuits where the high-frequency transistors operate in a complementary way. This may be due to internal defects in the switching transistors or some unnecessary inherent delay in their control signals. In this research work, a simplified AC–AC converter is developed that does not need alignment of high-frequency control with the polarity of the source voltage. With this approach, high-frequency signals can be generated with the help of any analog or digital control system. By applying this technique, only one high-frequency control signal is generated and applied in AC circuits, as in a DC converter, without applying a highly sensitive polarity sensing circuit. So, controlling complications is drastically simplified. The circuit and configuration always avoid the current interruption problem of filtering the inductor. The proposed control and circuit topology are tested both in computer-based simulation and practically developed circuits. The results obtained from these platforms endorse the effectiveness and validation of the proposed work.