Balancing Capability Research Articles

Development of a maintenance scheduling method for power generators considering large penetration of variable renewable energy sources and system inertia

AbstractConventional methods to schedule power generators maintenance aim to secure enough supply reserve margin to the power system when its power generators have to go under maintenance. However, the use of such methods in scenarios of large penetration of VRE, might be problematic. This is because in such scenarios conventional scheduling methods might inadvertently concentrate maintenance operations when residual demand is particularly low, creating situations in which there is insufficient supply‐demand balancing capability and inertia to operate the power system properly. In this study, we present the development of a new method to schedule generator maintenance that ensure inertia and balancing capability constraints, and show its effectiveness.

To Observe the Dynamic Balance Problem in Deaf Children`s Via Four Square Step Test

Background: Hearing loss is often associated with challenges in dynamic balance among children, impacting their daily activities and quality of life. This study aims to explore the relationship between varying degrees of hearing loss and dynamic balance capabilities among children, addressing a gap in current research on the physiological impacts of auditory impairments. Objective: To assess and compare the dynamic balance of children with different severities of hearing loss and to establish if there is a linear relationship between hearing loss severity and balance performance. Methods: A total of 302 children aged 4 to 15 years with varying degrees of hearing loss were recruited for this study. Participants were categorized into subgroups labeled as profound, severe, moderate, and minor hearing loss based on stop-watch tests. The Four Box Step Test was employed to measure each participant's dynamic balance. Data normality was verified using the Kolmogorov-Smirnov test, and differences among groups were analyzed using two-way ANOVA and Tukey's post hoc test. Results: This study assessed the dynamic balance in children with varying degrees of hearing loss, analyzing data from 172 participants aged 4 to 15 years. The analysis revealed significant gender differences in dynamic balance, with males generally outperforming females. The age-based assessment demonstrated a negative linear trend, indicating that dynamic balance decreases as age increases, with significant variances across different age groups (F(2, 166) = 3.91, p = 0.022). Two-way ANOVA confirmed no significant interaction between gender and age on dynamic balance (F(2, 166) = 2.82, p = 0.062), highlighting that while age significantly affects balance, gender alone does not show a substantial impact. Conclusion: Dynamic balance decreases as the severity of hearing loss increases, with males generally outperforming females. This study underscores the importance of incorporating balance training in rehabilitation programs for children with hearing loss to enhance their motor performance and safety.

Working for the future is more than foreseeing the future: Impact of the balanced organizational capabilities on the proactive policy orientation

This study explores what kinds of (and how) organizational capabilities (benchmarking, modeling, forecasting, and backcasting), respectively and collectively, help an organization to have a more proactive policy orientation. An analysis of the public agencies in South Korea in 2021 shows several significant findings. First, all four of the organizational capabilities are conducive to a proactive policy orientation, which may be intuitively acceptable. Second, however, in contrast to expectation, the relative impact of forecasting capability on proactive policy orientation turned out to be the weakest among the four capabilities. An interpretation of these findings indicates that, proactive policies might be better produced in the organizational environment where forecasting can be supported by empirical evidence (benchmarking), methodical reasoning (modeling), and tangible planning (backcasting).

A Mathematical Structural Modulation Method for Neutral-Point Potential Balancing of Three-Level Neutral-Point-Clamped Converters

To achieve the fast neutral-point potential balance of three-level neutral-point-clamped (3L-NPC) converters, a mathematical structural modulation method is presented in this paper, featuring fast balance capability, low computation, and easy implementation. In this method, the duty cycle is decomposed into the differential-mode component (DMC) and the common-mode component (CMC). The CMC is used to synthesize the AC output voltage while the DMC is adopted to control the neutral-point potential. Based on the fractional-order sliding-mode control theory, the DMC is constructed. As a result, neutral-point potential balancing in a pre-calculated time is achieved. Finally, the effectiveness of the proposed method is verified by experimental results.

Compressed Sensing Image Reconstruction with Fast Convolution Filtering

Image reconstruction is a crucial aspect of computational imaging. The compressed sensing reconstruction (CS) method has been developed to obtain high-quality images. However, the CS method is commonly time-consuming in image reconstruction. To overcome this drawback, we propose a compressed sensing reconstruction method with fast convolution filtering (F-CS method), which significantly increases reconstruction speed by reducing the number of convolution operations without image fill. The experimental results show that by using the F-CS method, the reconstruction speed can be increased by a factor of 7 compared to the conventional CS method. Moreover, the F-CS method proposed in this paper is compared with the back-propagation reconstruction (BP) method and super-resolution reconstruction (SR) method, and it is validated that the proposed method has a lower computational resource cost for high-quality image reconstruction and exhibits a much more balanced capability.

Proportional sway-based electrotactile feedback improves lateral standing balance.

Plantar cutaneous augmentation is a promising approach in balance rehabilitation by enhancing motion-dependent sensory feedback. The effect of plantar cutaneous augmentation on balance has been mainly investigated in its passive form (e.g., textured insole) or on lower-limb amputees. In this study, we tested the effect of plantar cutaneous augmentation on balance in its active form (i.e., electrical stimulation) for individuals with intact limbs. Ten healthy subjects participated in the study and were instructed to maintain their balance as long as possible on the balance board, with or without electrotactile feedback evoked on the medial side of the heel, synched with the lateral board sway. Electrotactile feedback was given in two different modes: 1) Discrete-mode E-stim as the stimulation on/off by a predefined threshold of lateral board sway and 2) Proportional-mode E-stim as the stimulation frequency proportional to the amount of lateral board sway. All subjects were distracted from the balancing task by the n-back counting task, to test subjects' balancing capability with minimal cognitive involvement. Proportional-mode E-stim, along with the n-back counting task, increased the balance time from 1.86 ± 0.03 s to 1.98 ± 0.04 s (p = 0.010). However, discrete-mode E-stim did not change the balance time (p = 0.669). Proportional-mode E-stim also increased the time duration per each swayed state (p = 0.035) while discrete-mode E-stim did not (p = 0.053). These results suggest that proportional-mode E-stim is more effective than discrete-mode E-stim on improving standing balance. It is perhaps because the proportional electrotactile feedback better mimics the natural tactile sensation of foot pressure than its discrete counterpart.

Asymmetrical multi‐level inverter by using space vector pulse width modulation technique for low and medium power applications

SummaryA DC to AC converter is developed in this paper. This proposes a single‐phase five‐level inverter is developed in such a way that one DC source is used. The structure of the inverter is modular and the capacitor has self‐voltage balancing capability, which eliminates the need for sensors or an additional control loop. This paper presents the schematic diagram of the proposed topology, principle of operation, and the concepts of sinusoidal pulse width modulation (SPWM) for single‐phase and space vector pulse width modulation (SVPWM) for three‐phase. To further prove the advantage, power loss, and parameter computations are calculated mathematically. Low‐voltage stress is achieved in the proposed topology because the blocking voltages of all the switches are constrained to the input voltage. A comparison table is presented between SPWM and SVPWM schemes in three‐phase inverter. The proposed asymmetrical five‐level configuration setup is constructed, and experiments are performed inside the laboratory. The controller of the converter has been implemented in the field‐programmable gate array (FPGA) platform. In order to confirm the viability of the suggested topology, experimental results are provided for single‐phase arrangement. By using the FPGA platform, real‐time implementation is done for a three‐phase inverter topology.

Immediate effects of lateral truncal tilt balance training with and without a wedge on subjective postural vertical and sitting balance in patients with subacute stroke: a randomised crossover trial

Background/Aims The subjective postural vertical is an important factor in maintaining sitting balance. However, specific training to improve verticality and sitting balance has yet to be established. The aim of this study was to clarify the effectiveness of lateral truncal tilt training, using a wedge, on subjective postural vertical, subjective postural vertical with eyes open and sitting balance in patients with subacute stroke. Methods In this randomised crossover trial, the immediate effects of lateral truncal tilt training were examined. Participants were allocated to one of two groups (group 1 and group 2). In group 1, after placing an inclined 10° tilt wedge on the participants' affected side, the participants moved their trunk laterally as far as possible toward the wedge side 60 times within 2 minutes. The participants in group 2 performed the same movement but without the wedge. This was performed once. The participants' subjective postural vertical, subjective postural vertical with eyes open and sitting pressure while they were tilted toward the frontal plane were measured at baseline, after the first intervention and after the second intervention. Following a 1-hour break, the groups crossed over. Repetition analysis was used at baseline and after both groups had competed the intervention both with and without the wedge. Results In total, 18 patients (mean age 68.7 years) participated in this study. Variabilities in subjective postural vertical with eyes open indicated a greater decrease in group 1 than group 2 (P<0.01). A significantly larger improvement in the balancing capabilities in the subjective postural vertical and sitting pressure was observed (P<0.01). The sitting pressure on the affected side in the subjective postural vertical with eyes open and subjective postural vertical showed a pre- and post-training interaction (P<0.01). Conclusions Lateral truncal tilt balance training using a wedge can improve postural verticality and improve sitting balance in people who have had a stroke. Implications for practice Stroke rehabilitation programmes can include wedge training to improve posture and sitting balance in people who have had a stroke, which can help these individuals to complete activities of daily living.

A Cascaded Multilevel Modular Energy Router Hybrid Photovoltaic and Energy Storage With Improved Power Balance Capability

A Cascaded Multilevel Modular Energy Router Hybrid Photovoltaic and Energy Storage With Improved Power Balance Capability

Comprehensive linear and nonlinear analysis of the effects of spinning on dynamic balancing ability in Hungarian folk dancers

PurposeIn the case of Hungarian folk dancers, it is crucial to maintain correct posture and promptly respond to imbalances. However, traditional dances often lack specific training to develop these skills.MethodsIn this present study, twelve dancers (8 male, 4 female, age: 21.7 ± 3.6 years) and ten non-dancers subjects forming a control group (6 male, 4 female, age: 21.6 ± 2.87 years) participated. During the measurements a 60-second long bipedal balancing test on the balance board was completed two times, and a spinning intervention was inserted in between the two sessions. The balance capabilities of the two groups were assessed through the characterization of motion on an unstable board, and the analysis of subject’s center of mass and head movements.ResultsDancers applied a more sophisticated and resource-intensive strategy to address the balancing task, yielding a better balancing performance in terms of balance board parameters. By preferring a solid stability in the medio-lateral direction, a greater fluctuation in the anterior-posterior direction can be observed (e.g., significantly lower SampEn values). The overall more successful performance is further evidenced by within-subject comparison since significant differences were observed mostly within the control group. Based on the results, the advanced balancing ability of the folk dancer group is more likely to be acquired through years of experience.ConclusionThe results indicate that additional specialized training could further enhance this ability, encouraging the reliance on poorly memorized corrective movements and reducing the risk of injury.

A Local Pre-Rerouting Algorithm to Combat Sun Outage for Inter-Satellite Links in Low Earth Orbit Satellite Networks

Satellite networks show the development trend in global coverage, flexible access, and reliable transmission. They are the key to building a wide coverage, massive connection, three-dimensional, all-round, all-weather, space-, air- and ground-integrated information network. Due to its high frequency and large bandwidth, the laser inter-satellite link (ISL) is easily interfered with by sunlight. When sun outage occurs, the laser inter-satellite link will be interrupted for a long time. Most of the existing satellite link failure-routing algorithms are distributed and have poor load balancing capabilities. The centralized algorithm calculates paths independently for different services, and the effect is not ideal. In this paper, a local pre-rerouting algorithm (LPRA) is proposed. The center node collects the link information from the limited area before sun outage and the service information in the link that is about to be interrupted, and reroutes these services before sun outage occurs. After the occurrence of sun outage, services that originally needed to go through the failed link are forwarded according to the path calculated in advance, thereby avoiding link congestion and reducing the packet loss rate. Simulation results show that the proposed algorithm performs better than existing algorithms in terms of packet loss ratio, total delay and load balancing capabilities.

Fault-Tolerant Analysis of 5-level Modified T-type and Packed U Cell MLI

ABSTRACT In this work, 5-level modified T-type and modified Packed-U-Cell (PUC) multilevel inverter (MLI) topologies are designed with reduced device count for the reliability analysis of the MLI under faulty conditions. This work aims to incorporate the fault either by loss of an individual switch or due to the loss of a single h-bridge leg. Also, the proposed T-type and PUC inverter have an inherent self-voltage balancing capability that reduces the complexity and enhances the circuit’s reliability. First, the proposed topologies are simulated using Matlab/Simulink environment, and the results obtained are then compared with the conventional MLI. Finally, both MLIs are experimentally tested on a laboratory prototype as a proof of concept to validate the analytical developments.

A hybrid mixed‐cells DC‐DC modular multilevel converter with balanced arm energy and DC fault blocking capability for high voltage direct current systems

SummaryDC‐DC converters play a vital role in the integration of renewable energy sources. Modular multilevel converter (MMC) has emerged as a highly promising option for high‐voltage high‐power applications, for DC‐AC and DC‐DC conversion, thanks to its distinctive characteristics. An inherent limitation of using traditional MMC in DC‐DC conversion is the occurrence of arm energy drift, leading to imbalanced voltages across capacitors of submodules (SMs). Many approaches have been presented in the literature to address the energy drift issue during DC‐DC conversion process. In this paper, a novel bidirectional hybrid modular multilevel DC‐DC converter with balanced arm energy has been proposed. The proposed converter consists of one high‐voltage valve and two legs. Each leg is equipped with half‐bridge submodules (HB‐SMs) in the upper arm and full‐bridge submodules (FB‐SMs) in the lower arm. The proposed architecture enables the parallel connection between series‐connected capacitors of the upper arm and series‐connected capacitors of the lower arm during the equalization period. The parallel connectivity enables the energy transfer between the upper and lower arms in the same leg, hence preventing energy drift issues. A detailed illustration of converter operational concept, mathematical analysis, design, and efficiency estimation are presented. The presented simulation and experimental results show the bidirectional power flow ability and the promising behavior of the proposed converter during normal operating conditions with balanced arm energy. Finally, a comparison between the proposed converter and other existing topologies has been made to show the superiority of the proposed converter over the other alternatives. The proposed converter has a lower count of insulated gate bipolar transistors (IGBTs) and eliminates the usage of isolating transformers when compared to the energy equalization modules approach. In addition, unlike the other alternatives, the proposed converter has a DC fault blocking capability.

Enhancing performance measurement of public procurement processes through the application of procurement delay index

Considering procurement process performance assessment, measurement systems such as balance scorecard and capability maturity models are used to assess procurement performance to give a reasonable indication of actual performance. These tools are ideal for practical applications that depend on other performance criteria but are short of comparing planned to actual timelines set for procurement processes. This fosters persistent delays in public procurement. Six Sigma implementation benefits including addressing process delays have fostered its implementation for service improvements. Unfortunately, Six Sigma implementation in public procurement is very rare largely due to its expensive nature. The objective of this study is to develop a Procurement Delay Index (PDindex): a performance measure in the context of a Six Sigma methodology that provides a specific value to describe the delays in the procurement process. To enhance uniformity in performance measurement of process timeliness, a rating scale for determining the timeliness of the procurement process is proposed. A practical demonstration of the application of PDindex for use by procurement professionals is also presented. PDindex serves as a standard by which to determine procurement processes’ timeliness and is less expensive to implement. A PDindex of 3σ has been recommended as the acceptable limit for procurement process delays.

Atrial Fibrillation Detection with Single-Lead Electrocardiogram Based on Temporal Convolutional Network-ResNet.

Atrial fibrillation, one of the most common persistent cardiac arrhythmias globally, is known for its rapid and irregular atrial rhythms. This study integrates the temporal convolutional network (TCN) and residual network (ResNet) frameworks to effectively classify atrial fibrillation in single-lead ECGs, thereby enhancing the application of neural networks in this field. Our model demonstrated significant success in detecting atrial fibrillation, with experimental results showing an accuracy rate of 97% and an F1 score of 87%. These figures indicate the model's exceptional performance in identifying both majority and minority classes, reflecting its balanced and accurate classification capability. This research offers new perspectives and tools for diagnosis and treatment in cardiology, grounded in advanced neural network technology.

A new evolutionary optimization algorithm with hybrid guidance mechanism for truck-multi drone delivery system

Synchronization of the Traveling Salesman Problem with Drone (TSP-D) is one of the most complex NP-hard combinatorial routing problems in the literature. The speeds, capacities and optimization constraints of the truck-drone pair are different from each other. These differences lead to the search space of TSP-D having a high geometric complexity and a large number of local solution traps. Being able to avoid local solution traps in the search space of TSP-D and accurately converge to the global optimal solution is the main challenge for evolutionary search algorithms. The way to overcome this challenge is to dynamically adapt exploitation and exploration behaviors during the search process and maintain these two in a balanced manner depending on the geometric structure of TSP-D's search space. To overcome this challenge, research consisting of three steps was conducted in this article: (i) three different guide selection methods, namely greedy, random and FDB-score based, were used to provide exploitation, exploration and balanced search capabilities, (ii) by hybridizing these three methods at different rates, guide selection strategies with different search capabilities were developed, (iii) by associating these hybrid guide selection strategies with different stages of the search process, the guidance mechanism was given a dynamic behavioral ability. Thus, the Fitness-Distance Balance-based evolutionary search algorithm (FDB-EA) was designed to achieve a sustainable exploitation-exploration balance in the search space of TSP-D and stably avoid local solution traps. To test the performance of the FDB-EA, the number of delivery points was set to 30, 50, 60, 80, and 100 and compared with twenty-seven powerful and current competing algorithms. According to the non-parametric Wilcoxon pairwise comparison results, FDB-EA outperformed all competing algorithms in all five different TSP-D problems. According to the results obtained from the stability analysis, the success rates and calculation times of FDB-EA, EA and AGDE algorithms were 88.00% (6308.79 sec), 58.40% (7377.43 sec) and 13.460% (34664.19 sec) respectively.

HiT-CIM: A High-Throughput Compute-In-Memory SRAM Architecture with Simultaneous Weight Loading/Computing and Balance Capabilities

HiT-CIM: A High-Throughput Compute-In-Memory SRAM Architecture with Simultaneous Weight Loading/Computing and Balance Capabilities

The Impact of Digital Capabilities on Sustainable Development in Guangdong's Manufacturing Sector: A Corporate Entrepreneurship Perspective

This study investigates the complex mechanisms by which digital capabilities influence the sustainable development performance of Guangdong manufacturing enterprises through corporate entrepreneurship. By analyzing digital operational and dynamic capabilities, the study highlights their respective and combined effects on sustainability. Empirical results reveal that digital operational capabilities positively impact sustainability, while digital dynamic capabilities exhibit an inverted U-shaped relationship. Additionally, digital capabilities significantly enhance corporate entrepreneurship, particularly in innovation, new business development, and strategic updates, with organizational readiness moderating these effects. The study underscores the need for balanced digital capabilities and organizational preparation to optimize sustainable development outcomes. This research provides theoretical insights and practical guidance for the digital transformation of manufacturing enterprises, emphasizing the critical role of digital capabilities in achieving sustainable performance.

Adaptive Control Strategy of Parallel Cascaded H-Bridge PV-Battery Hybrid Inverters for Enhanced Power Balance Capability

Adaptive Control Strategy of Parallel Cascaded H-Bridge PV-Battery Hybrid Inverters for Enhanced Power Balance Capability

The effect of functional fitness training on the balance ability of students specializing in the high jump

Abstract This study delves into how targeted exercise regimes can bolster static and dynamic balancing capabilities by exploring the nexus between functional physical training and balance proficiency in high jump athletes. Through rigorous evaluation of 80 students using the entropy weight-TOPSIS method, our four-month investigation revealed marked enhancements in balance. Notably, static balance improved by 8-10%, while dynamic balance saw a 12-15% uptick, emphasizing the efficacy of functional training in optimizing athletic performance and mitigating injury risks. The control group’s unchanged balance further underscores the specific benefits of our training regimen.