High-performance Systems Research Articles

Simultaneous inactivation of Microcystis aeruginosa and degradation of microcystin-LR in water by activation of periodate with sunlight

Harmful algal blooms pose tremendous threats to ecological safety and human health. In this study, simulated solar light (SSL) irradiation was used to activate periodate (PI) for the inactivation of Microcystis aeruginosa and degradation of microcystin-LR (MC-LR). We found that PI-SSL system could effectively inactivate 5 × 106 cells·mL−1 algal cells below the limit of detection within 180 min. ·OH and iodine (IO3· and IO4·) radicals generated in PI-SSL system could rupture cell membranes, releasing intracellular substances including MC-LR into the reaction system. However, the released MC-LR could be degraded into non-toxic small molecules via hydroxylation and ring cleavage processes in PI-SSL system, reducing their environmental risks. High algae inactivation performance of PI-SSL system in solution with a wide pH range (3–9), with the coexisting anions (Cl−, NO3− and SO42−) and the copresence of natural organic matters (humic acid and fulvic acid), real water (lake water and river water), as well as in continuous-flow reactor (14 h) were also achieved. In addition, under natural sunlight irradiation, effective algae inactivation could also be achieved in an enlarged reactor (1 L). Overall, our study showed that PI-SSL system could avoid the inference by the background substances and could be employed as a feasible technique to treat algal bloom water.

Large-scale photonic computing with nonlinear disordered media.

Neural networks find widespread use in scientific and technological applications, yet their implementations in conventional computers have encountered bottlenecks due to ever-expanding computational needs. Photonic computing is a promising neuromorphic platform with potential advantages of massive parallelism, ultralow latency and reduced energy consumption but mostly for computing linear operations. Here we demonstrate a large-scale, high-performance nonlinear photonic neural system based on a disordered polycrystalline slab composed of lithium niobate nanocrystals. Mediated by random quasi-phase-matching and multiple scattering, linear and nonlinear optical speckle features are generated as the interplay between the simultaneous linear random scattering and the second-harmonic generation, defining a complex neural network in which the second-order nonlinearity acts as internal nonlinear activation functions. Benchmarked against linear random projection, such nonlinear mapping embedded with rich physical computational operations shows improved performance across a large collection of machine learning tasks in image classification, regression and graph classification. Demonstrating up to 27,648 input and 3,500 nonlinear output nodes, the combination of optical nonlinearity and random scattering serves as a scalable computing engine for diverse applications.

Hybrid Advanced Control Strategy for Post-Combustion Carbon Capture Plant by Integrating PI and Model-Based Approaches

Even though the energy penalties and solvent regeneration costs associated with amine-based absorption/stripping systems are important challenges, this technology remains highly recommended for post-combustion decarbonization systems given its proven capture efficacy and technical maturity. This study introduces a novel centralized and decentralized hybrid control strategy for the post-combustion carbon capture plant, aimed at mitigating main disturbances and sustaining high system performance. The strategy is rooted in a comprehensive mathematical model encompassing absorption and desorption columns, heat exchangers and a buffer tank, ensuring smooth operation and energy efficiency. The buffer tank is equipped with three control loops to finely regulate absorber inlet solvent solution parameters, preventing disturbance recirculation from the desorber. Additionally, a model-based controller, utilizing the model predictive control (MPC) algorithm, maintains a carbon capture yield of 90% and stabilizes the reboiler liquid temperature at 394.5 K by manipulating the influent flue gas to the lean solvent flowrates ratio and the heat duty of the reboiler. The hybrid MPC approach reveals efficiency in simultaneously managing targeted variables and handling complex input–output interactions. It consistently maintains the controlled variables at desired setpoints despite CO2 flue gas flow disturbances, achieving reduced settling time and low overshoot results. The hybrid control strategy, benefitting from the constraint handling ability of MPC, succeeds in keeping the carbon capture yield above the preset minimum value of 86% at all times, while the energy performance index remains below the favorable value of 3.1 MJ/kgCO2.

Phytochemical Analysis, Acetylcholinesterase Inhibition, Antidiabetic and Antioxidant Activities of Atriplex halimus L. (Amaranthaceae Juss.).

Mediterranean saltbush Atriplex halimus L. (Amaranthaceae) from different bioclimatic arid zones (ten wild populations) were studied. Phenols contents, flavonoids, flavonols, tannins and anthocyanins were determined and then tested for their antioxidants, antidiabetic and anti-acetylcholinesterase (AChE) activities. Levels of total polyphenols including flavonoids and flavonols, tannins and anthocyanins were high and varied significantly among analyzed populations. Nine phenolic acids and four flavonoids were identified for the first time in the methanolic fraction and quantified by liquid high-performance chromatography system HPLC (DAD). All extracts showed a substantial antioxidant activity, as assessed by DPPH assay (1,1-diphenyl-2-picrylhydrazyl free radical) (IC50DPPH=147.3for population of Seliena), Ferric Reducing Antioxidant Power (FRAP; IC50FRAP=3.2 for populations of Sousse and Kairouan), and Chelation Fer test (IC50FerCh=1.5 μg/mL for populations of El-hamma and Mednine). Atriplex halimus possessed a high inhibitory effect against α-amylase activity (up to 2.6 mg ACE/gE), a moderate activity for α-glucosidase (up to 91.0 mg ACE/gE) and AChE (up to 147.2 μg/mL) compared to standard. The analyzed populations were isolated and subdivided into three distinct groups, without any bioclimatic structuration. Enzymatic activities seem to be associated with the presence, in plant extracts, of other classes of compounds then phenols such as terpenes, sterols, saponins, coumarins and carotenoids.

Design and development of the DE-SPECT system: a clinical SPECT system for broadband multi-isotope imaging of peripheral vascular disease

Objective. Peripheral Vascular Disease (PVD) affects more than 230 million people worldwide and is one of the leading causes of disability among people over age 60. Nowadays, PVD remains largely underdiagnosed and undertreated, and requires the development of tailored diagnostic approaches. We present the full design of the Dynamic Extremity SPECT (DE-SPECT) system, the first organ-dedicated SPECT system for lower extremity imaging, based on 1 cm thick Cadmium Zinc Telluride (CZT) spectrometers and a dynamic dual field-of-view (FOV) synthetic compound-eye (SCE) collimator. Approach. The proposed DE-SPECT detection system consists of 48 1 cm thick 3D-position-sensitive CZT spectrometers arranged in a partial ring of 59 cm in diameter in a checkerboard pattern. The detection system is coupled with a compact dynamic SCE collimator that allows the user to select between two different FOVs at any time during an imaging study: a wide-FOV (28 cm diameter) configuration for dual-leg or scout imaging or a high-resolution and high-sensitivity (HR-HS) FOV (16 cm diameter) for single-leg or focused imaging. Main results. The preliminary experimental data show that the CZT spectrometer achieves a 3D intrinsic spatial resolution of <0.75 mm FWHM and an excellent energy resolution over a broad energy range (2.6 keV FWHM at 218, 3.3 keV at 440 keV). From simulations, the wide-FOV configuration offers a 0.034% averaged sensitivity at 140 keV and <8 mm spatial resolution, whereas the HR-HS configuration presents a peak central sensitivity of 0.07% at 140 keV and a ∼5 mm spatial resolution. The dynamic SCE collimator enables the capability to perform joint reconstructions that would ensure an overall improvement in imaging performance. Significance. The DE-SPECT system is a stationary and high-performance SPECT system that offers an excellent spectroscopic performance with a unique computer-controlled dual-FOV imaging capability, and a relatively high sensitivity for multi-tracer and multi-functional SPECT imaging of the extremities.

Aqueous Electrolyte With Weak Hydrogen Bonds for Four-Electron Zinc-Iodine Battery Operates in a Wide Temperature Range.

In the pursuit of high-performance energy storage systems, four-electron zinc-iodine aqueous batteries (4eZIBs) with successive I-/I2/I+ redox couples are appealing for their potential to deliver high energy density and resource abundance. However, susceptibility of positive valence I+ to hydrolysis and instability of Zn plating/stripping in conventional aqueous electrolyte pose significant challenges. In response, polyethylene glycol (PEG 200) is introduced as co-solvent in 2 m ZnCl2 aqueous solution to design a wide temperature electrolyte. Through a comprehensive investigation combining spectroscopic characterizations and theoretical simulations, it is elucidated that PEG disrupts the intrinsic strong H-bonds of water by global weak PEG-H2O interaction, which strengthens the O─H covalent bond of water and intensifies the coordination with Zn2+. This synergistic effect substantially reduces water activity to restrain the I+ hydrolysis, facilitating I-/I2/I+ redox kinetics, mitigating I3 - formation and smoothening Zn deposition. The 4eZIBs in the optimized hybrid electrolyte not only deliver superior cyclability with a low fading rate of 0.0009% per cycle over 20000 cycles and a close-to-unit coulombic efficiency but also exhibit stable performance in a wide temperature range from 40°C to -40°C. This study offers valuable insights into the rational design of electrolytes for 4eZIBs.

Impact of Transformational Leadership toward Organization Efficacy in Nigeria Petroleum Company

This study investigates the relationship between transformational work performance and organizational efficacy in selected Nigerian petroleum companies. It is anchored in transformational leadership theory and the high-performance work systems (HPWS) framework. Transformational leadership, pioneered by Burns and developed by Bass, emphasizes leaders' influence through idealized influence, inspirational motivation, intellectual stimulation, and individualized consideration. The HPWS framework highlights HR practices that enhance employee skills, motivation, and opportunity, ultimately driving organizational performance. While existing literature on transformational leadership mainly focuses on Western contexts, this study seeks to address the gaps by examining its applicability in Nigeria's petroleum sector. Methodological limitations, organizational-level focus, and contextual specificity are identified as gaps in prior research. The study aims to investigate these relationships in Nigeria, considering sociocultural variations and employing a mixed-methods approach. Through structured interviews and questionnaire surveys, data were collected from 280 employees. The data analysis included regression analysis, correlation analysis, and reliability testing. Results indicate a significant positive relationship between transformational leadership dimensions and organizational efficacy. The study contributes to understanding the dynamics of transformational leadership and HPWS in a developing economy context, particularly within Nigeria's petroleum industry. Future research should explore these relationships further, considering contextual factors and employing longitudinal designs.

Multi-criteria Analysis and Optimization in the AMPERE Ecosystem

The AMPERE project is developing the next generation of high-performance and energy efficient Cyber-Physical Systems supporting multi-criteria optimization. This paper provides the general overview of the AMPERE approach to analyse and optimize parallel real-time applications in heterogeneous platforms. More specifically, it details how parallel OpenMP programs are generated from AMALTHEA models, and the multi-criteria optimization methodology, considering the fault-tolerance, time and energy properties of the targeted applications.

Cattaneo-Christov heat flux effect on Darcy-Forchheimer dual-phase dusty shear-thickening carreau hybrid nanofluid flow along a stretched vertical cylinder

This research ventures into the convoluted behavior of dusty Copper - Titanium Dioxide and Water shear-thickening Carreau hybrid nanofluid flow within a porous vertical cylinder, incorporating the effects of viscous dissipation and the Cattaneo-Christov heat flux model. By applying the Runge-Kutta-Fehlberg fourth-order method alongside the shooting technique, we address the nonlinear coupled ordinary differential equations governing this flow. The study systematically investigates the impact of various dimensionless parameters on critical flow characteristics such as velocity and thermal profiles, skin friction coefficient, and thermal transfer rate. Our findings indicate that increasing local Weissenberg numbers and power law indices for the Carreau fluid model enhances velocity distribution while reducing the temperature profile. Higher Weissenberg numbers correlate with a decreased skin friction coefficient and an elevated Nusselt number. Initially, the curvature parameter shows a gradual increase in the fluid phase of the velocity profile, but it experiences a significant surge near the boundary. The heat transfer rate diminishes with rising values of the porosity and Forchheimer parameters. Notably, the study reveals the remarkable benefits of the dusty Carreau hybrid nanofluid, demonstrating a 39% increase in absolute shear stress compared to the dusty Carreau nanofluid, highlighting its potential for improved momentum transfer. Additionally, a 20% enhancement in heat transfer rate underscores its suitability for high-performance engineering and heat transfer systems. These results offer promising advancements for industries requiring efficient heat and momentum transfer, contributing to superior performance and energy efficiency.

Novel full-scale model verified by atomic surface and developed composite microfiber and slurry polishing system

Polishing mechanisms between fibers of a polishing pad and slurry are elusive, rising a challenge to develop high-performance composite polishing system. To solve this challenge, a novel full-scale model is proposed from mm to nm, consisting of macro, meso, micro and nanoscale. The model is verified by atomic surface and developed composite microfiber and slurry polishing system. Prior to chemical mechanical polishing, fused silica was polished by ceria slurry. A novel polishing pad was prepared using microfibers with a diameter of 2.5 μm, and a novel green slurry contained silica abrasives, hydrogen peroxide, sodium carbonate, sorbitol and xanthan gum. After CMP, an atomic surface with Ra of 0.108 nm was achieved, and the thickness of damaged layer is 1.95 nm. In terms of the macroscale model suggested, the maximum stress on the microfiber pad decreased 417.7 %, and the direct contact area increased 41.23 % compared with those of a commercial nonwoven pad. The peak stress exceeded 1 MPa on the commercial pad, while it reduced to about one fourth on the developed microfiber pad, according to the mesoscale fiber-slurry model proposed. Reactive force field molecular dynamics simulations, i.e. nanoscale model, reveal that a slurry layer existing at interface effectively impedes direct contact between abrasives and fused silica. With increasing the polishing load, material removal mode transformed from an atom to atomic chains. The constructed full-scale model and developed composite polishing system provide new insights to analyze, design and manufacture high-performance polishing pads, slurry and system.

Calibration and context in human evaluation of machine translation

Abstract Human evaluation of machine translation is considered the “gold standard” for evaluation, but it remains a challenging task for which to define best practices. Recent work has focused on incorporating intersentential context into human evaluation, to better distinguish between high-performing machine translation systems and human translations. In this work, we examine several ways that such context influences evaluation and evaluation protocols. We take a close look at annotator variation through the lens of calibration sets and focus on the implications for context-aware evaluation protocols. We then demonstrate one way in which degraded target-side intersentential context can influence annotator scores of individual sentences, a finding that supports the context-aware approach to evaluation and which also has implications for best practices in evaluation protocols.

Cancer care during a time of crisis: Israel’s experience during wartime.

e23030 Background: During the last decades, there have been many crises in the world, including COVID-19, the Ukraine-Russia war and major tsunamis and earthquakes. These situations create challenges for providing appropriate care for cancer patients. It remains an important research priority to understand how to improve care delivery for cancer patients under conditions of stress or emergency. Methods: Israel has one of the highest-quality healthcare systems in the world. Strengths of the health system include advanced technology, universal health insurance, and four strong health maintenance organizations. Israel’s health system recently performed relatively well during the COVID-19 pandemic. Here, we report on system efforts to continue providing care despite the massive terrorist attack by Hamas of October 7, 2023, the ongoing rocket fire, and the mobilization of young and middle-aged adults to the army, which led to staff shortages. Our report focuses in particular on efforts to maintain continuity and quality of care for cancer patients. Results: There have been three main pillars of Israel’s efforts to maintain care for cancer patients despite the challenges. 1) We activated strategies learned from previous events, including the COVID-19 pandemic and other wars. This enabled continuing treatment of cancer patients, including those who had been evacuated from border-adjacent areas, in oncology departments that are either missile-proof or adjacent to a protected area. 2) The existence of universal health insurance, together with strong health maintenance organizations, enabled us to fill in gaps in social needs and ensure that no patient is “left behind”. This, in turn, allowed patients and their care teams to continue their cancer care without reimbursement barriers or other interruptions, despite the challenges. 3) There was a massive groundswell of volunteerism and lay-led social service initiatives. Almost half (48.6%) of the Israeli population engaged in some volunteer activity during the first two weeks of the war. This included volunteers who provided transportation for patients to and from treatments, donation of medications aimed at helping evacuees from border areas, and volunteer medical staff, such as recent retirees. These civil initiatives played a critical role in providing the initial response to the urgent needs that were left unaddressed by the government. Conclusions: We identified three main pillars that enabled continuity and high quality of care for cancer patients to continue despite a major crisis. A rapid response due to having similar, previous experiences and ready plans. A high-performance and resilient health delivery system, and lay volunteerism in times of crisis. While Israel’s challenges in the present period are unique, nevertheless lessons can be learned by health systems that wish to become more resilient and able to provide adequate care in times of crisis.

Comparative Analysis of 5-Level and 7-Level Single-Phase Cascaded H-bridge Multilevel Inverters

The demand for high-performance, efficient, and reliable power electronic systems has been steadily increasing in various industrial applications, including renewable energy systems, electric vehicles, and smart grids. In response to this demand, the Cascaded H-Bridge Multi-level Inverter (CHB-MLI) has emerged as a promising solution, offering advantages such as improved voltage waveform quality, reduced harmonic distortion, and enhanced power handling capabilities. The CHB-MLI is characterized by its modular structure, comprising multiple H-bridge cells cascaded in series. Each H-bridge cell operates with a separate DC power source, enabling the generation of stepped voltage levels at the inverter output. By intelligently controlling the individual H-bridge cells, the CHB-MLI achieves the synthesis of a high-quality multilevel output voltage waveform. The different multi-level inverter topologies are Diode-Clamped MLI, Capacitor-Clamped MLI and Cascaded H-bridge MLI. This paper focused on key aspects like design, simulation, control strategies, performance evaluation, overall comparison and analysis of 5-level and 7-level CHB-MLIs. By addressing these aspects, this paper aimed to contribute to the advancement of power electronics technology and promote the adoption of the CHB-MLI in real-world applications, fostering energy efficiency and sustainability in power conversion systems. Index Terms: Inverter, Multi-level inverter, CHBMLI, switching, SPWM, MCSPWM, gate signal, waveform, harmonics, THD, MATLAB.

High-performance Smart Home System based on Optimization Algorithm

Background: With the recent COVID-19 pandemic, people have become increasingly concerned about their physical health. Therefore, the ability to monitor changes in the surrounding environment in real-time and automatically improve the environment has become a current hot topic to improve the overall health level. Objective: This article describes the design of a high-performance intelligent home system that can simultaneously perform monitoring and automatic adjustment functions. Methods: The ESP8266 was used as the core controller, and the DHT11 and G12-04 sensors were used to collect data, such as temperature, humidity, and ambient light intensity. The sampling frequency was increased and the sampled data were processed to improve data accuracy. The sampled data were wirelessly transmitted to a PC or mobile terminal for real-time display. When the sampled data underwent sudden changes, an alert message was sent via the mobile terminal. Based on the real-time changes in ambient light, an improved lighting brightness adjustment algorithm combining bang-bang and single neuron adaptive PID control was used to adjust the lighting brightness. Results: After testing the system designed in this paper and analyzing the errors compared to standard values, the temperature measurement error ranged from 0% to 0.01107%, and the humidity measurement error ranged from 0% to 0.03797%. The improved algorithm was simulated and tested using MATLAB software and compared with traditional PID algorithms and single-neuron adaptive PID algorithms. The improved algorithm did not overshoot during adjustment, and the system reached a steady state much faster than traditional algorithms. Conclusion: The system showed good performance in real-time, stability, and accuracy, fully demonstrating the effectiveness of the devices and algorithms used in the system. This provides ideas for the design and improvement of future smart homes.

Transforming Ethiopian higher education institutions: Multilevel analysis of high-performance work systems, engagement, and justice

Perceived HPWSs (PS-HPWSs) are increasingly indicated for understanding the relationship between organizational HPWSs and employee-level outcomes. However, the mediating effect of perceived HPWSs is inconsistent and unclear. Hence, relying on integrated HPWS strength and signal theories, we tested whether PS-HPWSs positively mediated the relationship between MR-HPWSs and engagement with data collected from multiple and multilevel sources of 102 department heads and 360 employees of three Ethiopian public higher education institutions from June 03/2023 to September 10/2023. We also tested the positive moderation impact of procedural justice between MR-HPWSs and PS-HPWSs and its conditional effect on engagement using the MLmed Beta macro SPSS package. Therefore, procedural justice moderates the mediation of PS-HPWSs between manager-rated HPWSs and employee engagement. Hence, this study will address the inconsistency of PS-HPWSs between manager-rated HPWSs through the moderation of procedural justice (one of nine features of HPWS strength); this in turn has an ample effect on engagement. Accordingly, further research should include one or more of the nine HPWS features as moderators of the mediating effect of PS-HPWSs.

A smart tablet-phone-based high-performance pancreatic cancer cell biosensing system for drug screening

Exploring more efficient pancreatic cancer drug screening platforms is of significant importance for accelerating the drug development process. In this study, we developed a high-sensitivity bioluminescence system based on smartphones and smart tablets, and constructed a pancreatic cancer drug screening platform (PCDSP) by combining the pancreatic cancer cell sensing model (PCCSM) on the multiwell plates (MTP). A smart tablet was used as the light source and a smartphone as the colorimetric sensing device. The smartphone dynamically controls the color and brightness displayed on the smart tablet to achieve lower LOD and wider detection ranges. We constructed PCCSM for 24 h, 48 h, and 72 h , and performed colorimetric experiments using both PCDSP and a commercial plate reader (CPR). The results showed that the PCDSP had a lower LOD than that of CPR. Moreover, PCDSP even exhibited a lower LOD for 24 h PCCSM testing compared to CPR for 48 h PCCSM testing, effectively shortening the drug evaluation process. Additionally, the PCDSP offers higher portability and efficiency compared with CPR, making it a promising platform for efficient pancreatic cancer drug screening.

MEASUREMENT OF BASIC HEMODYNAMICS DURING MULTIPOST TRANSCUTANEOUS EXTERNAL EAR STIMULATION: A TWO-CASE STUDY

The objectives of the investigation were to assess the short-term responses of the cardio-vascular system on the multipost transcutaneous stimulation (tANS) of the external ear (EE). The scope was to measure the forefinger photopleths (FPPG), toe photopleths (TPPG), aortic phonocardiogram (APCG), mitral phonocardiogram (MPCG) and brachial arterial blood pressure (BABP), assuming that they could be altered with the tANS. For the tANS, stimulator, two silicone ear plugs with four platinum electrodes each, and a large common electrode (CE), were used. Trials were carried out with two female volunteers, aged 25 years and 28 years. To capture the heart sounds, two customized electronic stethoscopes (transducers) were used. BABP was measured using a pressure transducer and blood-pressure appliance. To measure the FPPGs, a pulse oximeter and SpO2 finger clip were used. To measure the TPPGs, another pulse oximeter and customized SpO2 foot clip was used. Signals were gathered using a high-performance data-acquisition system. An offline analysis was made just before and just after the start of the tANS. To record the pulsations in the right brachial artery, the 2D ultrasound mode (B) of the ultrasound device was used before and during the tANS. Then, diagrams showing the vein cross-sectional area over time were constructed. The results show that vascular time intervals between heart sounds S1 and S2, captured as APCG and systolic peaks of the FPPG in the second volunteer, were slightly larger during the separate tANS of the left white (LW) and (RW) EE post than before the tANS. Furthermore, vascular time intervals between the heart sounds S1 and S2, captured as MPCG and systolic peaks of the TPPG in the second volunteer, were slightly smaller during the separate tANS of LW and RW EE post than before the tANS. Finally, tANS of the LW post elicited a slightly lower heart rate than the one measured when LW was not stimulated. In contrast, the tANS of the RW post elicited a slightly higher heart rate than the one measured when RW was not stimulated. It was also shown that the pattern of the vein cross-sectional area over time with tANS was different compared to both the FPPG and TPPG.

RPCA-based thermoacoustic imaging for microwave ablation monitoring

Microwave ablation (MWA) is a potent cancer treatment tool, but its effectiveness can be hindered by the lack of visual feedback. This paper validates the feasibility of using microwave-induced thermoacoustic imaging (TAI) technique to monitor the MWA process. A feasibility analysis was conducted at the principle level and a high-performance real-time TAI system was introduced. To address the interference caused by MWA, a robust principal component analysis (RPCA)-based method for TAI was proposed. This method leverages the correlation between multiple signal frames to eliminate interference. RPCA’s effectiveness in TAI was demonstrated through three sets of different experiments. Experiments demonstrated that TAI can effectively monitors the MWA process. This work represents the first application of RPCA-related matrix decomposition methods in TAI, paving the way for the application of TAI in more complex clinical scenarios. By providing rapid and accurate visual feedback, this research advances MWA technology.

Overview and development of PID control

Proportional integral differential control, referred to as PID control, is one of the earliest developed control methods, which is widely used in industrial process control because of its simple control algorithm, high reliability and good robustness. The classic PID controller is the simplest control system, but the actual control object usually has the characteristics of strong interference, transient uncertainty, nonlinearity, etc, so it is difficult to achieve the ideal control effect with the classic PID controller. In addition, with complex parameter tuning methods, it is often difficult to find an optimal result for the parameters of the classical PID controller. These factors lead to the fact that classical PID control cannot be applied to complex systems and high-performance systems, so people continue to develop PID control methods, introduce new models, and develop fuzzy PID controllers, expert PID controllers, neural network PID controllers, and PID controllers based on genetic algorithms. This paper will review the development history of PID controllers, and introduce fuzzy PID controllers, expert PID controllers, neural network PID controllers, and PID controllers based on genetic algorithms. The research status and future development prospects of these controllers are also prospected.

Universal health coverage and equal access in Sweden: a century-long perspective on macro-level policy

BackgroundWhen today’s efforts to achieve universal health coverage are mainly directed towards low-income settings, it is perhaps easy to forget that countries considered to have universal, comprehensive and high-performing health systems have also undergone this journey. In this article, the aim is to provide a century-long perspective to illustrate Sweden’s long and ongoing journey towards universal health coverage and equal access to healthcare.MethodsThe focus is on macro-level policy. A document analysis is divided into three broad eras (1919–1955; 1955–1989; 1989–) and synthesises seven points in time when policies relevant to overarching goals and regulation of universal health coverage and equal access were proposed and/or implemented. The development is analysed and concluded in relation to two egalitarian goals in the context of health: equality of access and equal treatment for equal need.ResultsOver the past century, macro-level policy evolved from the concept of creating access for the neediest and those reliant on wages for their survival to a mandatory insurance with equal right to healthcare for all. However, universal health coverage was not achieved until 1955, and individuals had to rely on their personal financial resources to cover the cost at the time of care utilization until the 1970s. It was not until 1983 that legislation explicitly stated that access to healthcare should be equal for the entire population (horizontal equity), while a vertical equity-principle was not added until 1997. Subsequently, ideas of free choice and privatization have gained significance. For instance, they aim to increase service access, addressing the Swedish health system’s Achilles’ heel in this regard. However, the principle of equal access for all is now being challenged by the emergence of private health insurance, which offers quicker access to services.Conclusions: brief summary and potential implicationsIt can be concluded that there is no perpetual Swedish healthcare model and various dimensions of access have been the focus of policy discussion. The discussion on access barriers has shifted from financial to personal and organizational ones. Today, Sweden still ranks high in terms of affordability and equity in international comparisons: although not as well as a decade ago. Whether this marks the beginning of a new trend intertwined with a decline in Sweden’s welfare ‘exceptionalism’, or is a temporary decline remains to be assessed in the future.