Switching Time Research Articles

Tolerability of Diquas LX on tear film and meibomian glands findings in a real clinical scenario.

Long-acting diquafosol ophthalmic solution (DQS-LX) has significant advantages regarding patient adherence owing to the reduced frequency of required eye drops; however, some patients prefer conventional diquafosol ophthalmic solution (DQS) over DQS-LX. Herein, to clarify the characteristics of patients according to their preference for ophthalmic solutions, dry eye (DE) and meibomian gland (MG) findings were retrospectively investigated. This study enrolled 341 patients with DE (mean age, 62.1 ± 11.7 years) treated at the Itoh Clinic between November 8, 2022, and July 31, 2023, who switched from DQS to DQS-LX. Patients were divided into two groups: those who continued DQS-LX administration (DQS-LX group) and those who wished to revert to conventional DQS (DQS group). Data regarding subjective symptoms assessed using the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, tear film breakup time (BUT), tear meniscus height (TMH), corneal and conjunctival fluorescein staining (CFS), conjunctival hyperemia/papilla, meiboscore, plugging, vascularity, meibum grade, and Schirmer's score at the time of DQS-LX switch were evaluated. Of the 341 patients, 31 (9.1%) wished to revert to conventional DQS. In total, 16 eyes of 16 patients in the DQS group and 32 eyes of 32 patients in the DQS-LX group-for whom complete data were available-were included in the analysis. The DQS-LX group had higher SPEED scores, lower TMHs (P < 0.001, respectively), shorter FBUTs, greater CFS findings, larger meibum grades, lower Schirmer scores, and more pluggings compared with the DQS group (P = 0.005, 0.001, 0.001, 0.046, 0.003, respectively). Meiboscores and vascularity did not differ significantly between the two groups (P = 0.73 and 0.39, respectively). In conclusion, patients with low tear film volume and DE complicated by moderate or severe meibomian gland dysfunction (MGD) preferred DQS-LX, while those with allergic findings preferred conventional DQS.

Finite-time formation trajectory tracking control for unmanned underwater vehicles with time delays and Markov-switch topology

ABSTRACT The formation trajectory tracking control strategy of unmanned underwater vehicles is proposed for communication time delay and communication topology random switching. The methods ensure that formation systems are finite-time bounded under discrete time. Firstly, based on the consistency theory and the exact feedback linearised dynamics model of unmanned underwater vehicle, a control strategy is proposed for discrete formation system with communication time delay. Secondly, a cooperative control method is designed for communication problems of Markovian switching topology and time delay. Then, definition of finite-time bounded and linear matrix inequality technique are applied to sufficient conditions of system stability for the above problem. Finally, the formation motion of discrete unmanned underwater vehicle system in three-dimensional space is simulated, fully demonstrating the feasibility of the method.

Ti3C2Tx‐MXene‐Based Color‐Indicative All‐Organic Electrochromic Supercapacitors

An all‐organic multifunctional solid‐state electrochromic supercapacitor has been designed by utilizing 2D‐MXene and a combination of viologen and polythiophene. The 2D MXene is synthesized using selective etching method and properly characterized; afterward, it is doped in ethyl viologen (EV) and a solid‐state electrochromic supercapacitor device is prepared having poly‐3‐hexylthiophene (P3HT) as complementary electrode. The prepared device gives high optical contrast (OC) (≈85%) and coloration efficiency (CE) (≈340 cm2 C−1) with ≈1 s of switching time in the visible spectrum at 515 nm. A similar color modulation is observed in NIR region also. Along with high electrochromic properties, the device takes almost 23.1 s for discharging and 6.7 s for charging, giving high Columbic efficiency due to the pseudocapacitor‐type charge storage property providing necessary electrons for the redox reaction to occur. The current study proposes a new MXene‐based recipe for designing multifunctional electrochromic supercapacitors with a promise for practical use.

Treatment opportunities for refractory immune thrombocytopenia

Background. Primary immune thrombocytopenia (ITP) is an orphan disease characterized by decreased platelet count in the peripheral blood which in some cases can cause bleeding of varying severity. Currently, the use of thrombopoietin receptor agonists (TPO-RAs) is recommended as the second line therapy for ITP as it allows to achieve high platelet response (PR), including complete, in 73 % of cases of chronic ITP and in 87 % of cases of newly diagnosed disease. The mechanism of action differs for different TPO-RAs. Given this fact, in cases of resistance or intolerance to therapy with one TPO-RA, attempts are made to switch to another. The effectiveness of this approach for overcoming ITP resistance varies from 50 to 93 % according to various publications. Aim. To assess the ability to achieve and maintain PR by switching from one TPO-RA to another in cases of resistance to the previous TPO-RA used in the second or subsequent lines of therapy. Materials and methods. The analysis included 59 patients who were resistant (in 2 cases intolerance was also noted) to TPO-RA therapy (received after standard therapy) who were prescribed TPO-RA treatment with a different mechanism of action: switch from romiplostim to eltrombopag (25 patients) or vice versa (34 patients). Both groups were comparable in terms of demographic characteristics and median platelet level at the time of TPO-RA switching. Results. PR was obtained in 76 % of cases, including complete response in 54 %, as a result of switching from one TPO-RA to another in 59 patients. Among 34 patients switched from eltrombopag to romiplostim, PR was achieved in 31 (91 %) patients, including complete response in 22 (65 %). Romiplostim was switched to eltrombopag in 25 patients, PR was achieved in 14 (56 %) with complete response in 10 (40 %). Conclusion. The study showed that PR can be achieved and maintained through switching from one TPO-RA to an alternative.

Directional switching behavior of swarming systems with social and nonlinear interactions

Coordinated directional switching can occur among members of many mobile biological communities. Some studies show that self-propelled particle models can describe the directional switching behavior well. The key to understanding group movement is to determine the influential factors relevant to directional switching behavior. This paper focuses on the impact of social and nonlinear interactions on the directional switching behavior observed in swarming systems. In which, the nonlinear interaction is represented as a function of a trade-off between the velocity and velocity direction of its neighbors. Based on the framework of dimension reduction theory, the high-dimensional complex model is simplified into a one-dimensional simple model, and the stationary probability density and mean switching time are obtained by theoretical analysis of the one-dimensional model. It can be seen that social and nonlinear interactions play an important role in regulating the directional switching behaviors of swarming systems. Specifically, the increase of group density and nonlinear parameter can inhibit the directional switches. For Erdös-Rényi networks, the large mean degree can suppress the directional switching behavior. For scale-free networks, increasing the degree heterogeneity can reduce the mean switching time. The results reveal the underlying mechanisms by which social and nonlinear interactions influence the directional switching behaviors of swarming systems, and provide a theoretical foundation for the design of bio-inspired devices with specific functions.

Fractionation dose optimization facilities the implementation of transmission proton FLASH-RT

Objective.The beam switching time and fractional dose influence the FLASH effect. A single-beam-per-fraction (SBPF) scheme using uniform fractional dose (UFD) has been proposed for FLASH- radiotherapy (FLASH-RT) to eliminate the beam switching time. Based on SBPF schemes, a fractionation dose optimization algorithm is proposed to optimize non-UFD plans to maximize the fractionation effect and dose-dependent FLASH effect.Approach.The UFD plan, containing five 236 MeV transmission proton beams, was optimized for 11 patients with peripheral lung cancer, with each beam delivering a uniform dose of 11 Gy to the target. Meanwhile, the non-UFD plan was optimized using fractionation dose optimization. To compare the two plans, the equivalent dose to 2 Gy (EQD2) for the target and normal tissues was calculated with anα/βratio of 10 and 3, respectively. Both UFD and non-UFD plans ensured that the target received an EQD2 of 96.3 Gy. To investigate the overall improvement in normal tissue sparing with the non-UFD plan, the FLASH-enhanced EQD2 was calculated.Main results.The fractional doses in non-UFD plans ranged between 5.0 Gy and 24.2 Gy. No significant differences were found in EQD22%and EQD298%of targets between UFD and non-UFD plans. However, theD95%of the target in non-UFD plans was significantly reduced by 15.1%. The sparing effect in non-UFD plans was significantly improved. The FLASH-enhanced EQD2meanin normal tissue and ipsilateral lung was significantly reduced by 3.5% and 10.4%, respectively, in non-UFD plans. The overall improvement is attributed to both the FLASH and fractionation effects.Significance.The fractionation dose optimization can address the limitation of multiple-beam FLASH-RT and utilize the relationship between fractional dose and FLASH effect. Consequently, the non-UFD scheme results in further improvements in normal tissue sparing compared to the UFD scheme, attributed to enhanced fractionation and FLASH effects.

Relaxed Stability and Non-weighted $$L_2$$-Gain Analysis for Asynchronously Switched Polynomial Fuzzy Systems

AbstractThis paper concerns the stability and non-weighted $$L_2$$ L 2 -gain analysis issues for the switched systems subject to asynchronous switching and external disturbance. By taking full advantage of the admissible edge-dependent average dwell time (AED-ADT) switching signal, a stability criterion of asynchronously switched systems is proposed to achieve a lower non-weighted $$L_2$$ L 2 -gain index than the existing results. Furthermore, the dynamics of switched systems are described by using the polynomial fuzzy model instead of the T-S fuzzy model, which can represent a wider range of nonlinear plants. For such asynchronously switched polynomial fuzzy systems, the relaxed conditions are derived through the membership-function-dependent (MFD) technique and novel high-order multiple Lyapunov functions (MLFs) construction method to guarantee less conservative stability and non-weighted $$L_2$$ L 2 -gain results. Finally, the superiority of the proposed approaches are verified through two simulation examples.

Intrinsically Stable Charged Domain Walls in Molecular Ferroelectric Thin Films

AbstractCharged domain walls in ferroelectrics hold great promise for applications in ferroelectric random‐access memory (FeRAM), with advantages such as low energy consumption, high density, and non‐destructive operation. Due to the mechanical compatibility condition, the neutral domain walls are dominant in traditional ferroelectric thin films. Herein, using phase‐field simulations, the formation of intrinsically stable charged domain walls (CDWs) in the molecular ferroelectric films is demonstrated, which can be mainly attributed to the small mechanical stiffness. The switching kinetics are further investigated for the CDWs, showing a lower switching barrier as compared to the neutral counterparts. Moreover, it is indicated that increasing the compressive misfit strain can lead to prolonged switching time, with a significantly increased switching energy barrier. These findings pave the way for the potential applications of metal‐free organic ferroelectric materials in FeRAM devices.

A numerical study of transformed mixed-integer optimal control problems

Time transformation is a ubiquitous tool in theoretical sciences, especially in physics. It can also be used to transform switched optimal control problems into control problems with a fixed switching order and purely continuous decisions. This approach is known either as enhanced time transformation, time-scaling, or switching time optimization (STO) for mixed-integer optimal control. The approach is well understood and used widely due to its many favorable properties. Recently, several extensions and algorithmic improvements have been proposed. We use an alternative formulation, the partial outer convexification (POC), to study convergence properties of (STO). We introduce the open-source software package ampl_mintoc (Sager et al., czeile/ampl_mintoc: Math programming c release, 2024, https://doi.org/10.5281/zenodo.12520490). It is based on AMPL, designed for the formulation of mixed-integer optimal control problems, and allows to use almost identical implementations for (STO) and (POC). We discuss and explain our main numerical result: (STO) is likely to result in more local minima for each discretization grid than (POC), but the number of local minima is asymptotically identical for both approaches.

Almost Sure Stability and Stabilization of Composite Switched Systems With Persistent Dwell Time Constraint.

This article is devoted to the exponential almost sure (EAS) stability and stabilization of continuous-time composite switched systems (CSSs) by employing a novel dual-switching mechanism, which incorporates both persistent dwell time (PDT) switching and a set of Markov processes. The interrelation between the parameters under the PDT constraint is established by ensuring that switching frequency remains within the maximum permissible range, which serves as a pivotal consideration in the stability analysis of CSSs subject to above-mentioned dual-switching mechanism. Furthermore, the sufficient conditions for achieving EAS-stability and stabilization of CSSs are established with the designed switching strategy. Our results, in contrast to previous works that are special cases of our study, are more general and less conservative. Three examples are presented to validate the developed theoretical results.

Secure IRS-assisted energy scavenging NOMA impaired by realistic factors

Intelligent reflective surface (IRS)-assisted energy scavenging (ES) non-orthogonal multiple access (NOMA) with jamming (sIEnoma) is promising for high spectral efficiency, energy efficiency, information security, and communication reliability. Nonetheless, practical imperfections, such as channel state information imperfection (CSIi), hardware imperfection (HWi), fading severity, and nonlinear energy scavenging (nlES) impact scavenged energy, information security, and communication reliability of sIEnoma. Accordingly, this paper proposes performance analysis for sIEnoma under these imperfections to quickly assess its potentials without time-consuming simulations. Results show that imperfections (HWi, CSIi, fading severity, nlES) and specifications (IRS, NOMA) significantly impact performance of sIEnoma. Nevertheless, proper adoption of power splitting factor, desired data rate, HWi level, and time switching coefficient can hinder complete outage in sIEnoma. Additionally, optimal metrics are achieved by configuring system parameters properly. Moreover, the proposed sIEnoma outperforms its baseline (IRS-assisted ES orthogonal multiple access with jamming).

Characterizing polarization switching kinetics of ferroelectric Hf0.5Zr0.5O2 at cryogenic temperature

We have characterized polarization switching kinetics of Hf0.5Zr0.5O2 (HZO) at cryogenic temperature (T) down to 100 K. By the nucleation-limited-switching model with Lorentzian distribution fittings, the dependences of the average switching time (log τ1) and switching time distribution (ω) on T are extracted. As T decreases from 300 to 100 K, log τ1 first rapidly decreases and then gradually stabilizes. Meanwhile, ω exhibits different trends under different external electric fields (Eext), decreasing under low Eext while increasing under high Eext, eventually stabilizing at non-zero constants. With the further decrease in T (&amp;lt;100 K), log τ1 and ω exhibited by HZO are almost unchanged, indicating the intrinsic properties of ferroelectric multiple domains, which are different from the prediction in previous literature studies that log τ1 and ω will linearly decrease as T decreases.

Performance analysis of shared relay CR-NOMA network based on SWIPT

With the development of wireless communication technology, the number of devices accessing the communication network is increasing. This paper addresses critical issues such as low spectrum resource utilization and the energy constraints of devices. The investigation focuses on the system performance of the shared relay Cognitive Radio Non-Orthogonal Multiple Access (CR-NOMA) network based on Simultaneous Wireless Information and Power Transfer (SWIPT) network model. Unlike the existing CR-NOMA model in which the secondary network user do not participate in the transmission of information from the primary network, we consider the secondary network near user as shared relay. The shared relay utilizes SWIPT technology to harvest energy using a nonlinear energy harvesting model. Additionally, the shared relay assists in transmitting information from the primary network base station to primary user, as well as from the secondary network base station to far user of the secondary network. Subsequently, we conduct a series of simulations to analyze the effects of Signal-to-Noise Ratio (SNR), power distribution factor, interference threshold, and time-switching (TS) factor on system performance. Furthermore, we compare and analyze the performance of our proposed network model against CR-NOMA network across three dimensions: outage probability, throughput, and energy efficiency. Our results demonstrate that the proposed network model exhibits superior outage performance and enhances user throughput compared to the CR-NOMA network. Additionally, it demonstrates improved energy efficiency compared to the shared relay CR-NOMA network, leading to an overall improvement in network performance.

Control of combustion phasing using accelerometer-based non-intrusive sensing

Abstract Measuring the combustion phasing of an engine using in-cylinder pressure sensors is well established. However, pressure sensors need to be directly exposed to the in-cylinder environment, requiring changes to the cylinder head. Several methods have been proposed for sensing combustion phasing non-intrusively by mounting an accelerometer on the engine block. This paper presents real-time control of combustion phasing in a compression-ignition engine using non-intrusive accelerometer-based sensing during a dynamic fuel switch. A systematic data-driven control framework capable of handling fuel switching in real time is used. The control is designed based on the pressure data, and the real-time implementation is performed using the accelerometer signal. Results from combustion phasing tracking experiments performed on a compression-ignition engine are presented.

Nonsymmetrical thermal conductivity along the director field in ferroelectric nematic liquid crystals.

The synthesis of ferroelectric nematic liquid crystals (FNLCs) concludes the long wait for their existence and potential usage in multiple liquid crystal based applications. In FNLCs, electric polarization in the nematic phase significantly decreases the switching time of in-on display pixels. In this article, we report the occurrence of translation symmetry breaking for heat propagation along the director field n[over ̂] in the ferroelectric nematic phase. Due to the C_{∞V} symmetry of such a phase and close similarity to the bent-core polar liquid crystal phase, a rank-3 tensor describes its scalar order parameter and algebraic deductions. The finite element simulations show the occurrence of the nonsymmetrical thermal conductivity along n[over ̂]. The preferential heat transport in FNLCs can allow them to work as an all-thermal monophase non-nanostructured single-material thermal rectifier. We expect that this study will contribute towards the FNLCs application as functional layers and inks.

Ultra high-speed 3D shape measurement technology for specular surfaces based on μPMD

Phase measuring deflectometry (PMD) has been extensively applied to measure specular surfaces due to its non-contact, high-precision, full-field measurement capabilities. Liquid crystal display (LCD) screen is the most common structured light source in PMD. However, the response time of liquid crystal molecules limits its frame rate to around 100 frames per second (fps). Therefore, it is quite difficult for traditional PMD to measure rapidly moving surfaces. This paper proposes a 3D dynamic sensing technique, microsecond-PMD (µPMD) based on the high-frame-rate sinusoidal fringe display (HSFD). In the proposed method, the switching time for each fringe pattern display is at a sub-microsecond level, enabling high-speed fringe acquisition with kHz-level area array detection or 100kHz-level line array scanning. The HSFD method uses a specially designed LED array and two-step optical expansion. The high-speed switching characteristic of LED sources is utilized to allow a superfast display rate. Moreover, the superior sinusoidal property can be achieved by the combination of the specially designed discrete sinusoidal LED array, the light-diffracting effect of orthogonal gratings, and the filtering effect of the light diffuser. The mechanism and analytic model of fringe generation are thoroughly analyzed and discussed in this work. Furthermore, the swarm optimization algorithm and corresponding weighted fringe quality evaluation function are presented to obtain the optimal fringes. To the best of our knowledge, the proposed µPMD, for the first time, achieved a superfast fringe acquisition rate of 4000fps with sub-micrometer precision in three-dimensional (3D) reconstruction for specular surfaces. We envision this proposal to be broadly implemented for real-time monitoring in manufacturing.

Bayesian optimization for quick determination of operating variables of simulated moving bed chromatography

The Simulated Moving Bed (SMB) is a continuous chromatographic separation process that operates on the principle of counter-current movement between the solid and liquid phases. Due to periodic switching of feed and product ports across numerous connected columns, adjusting SMB operating variables such as feed and product flow rates and switching time to achieve desired separations is challenging. While equilibrium theory can help narrow the search space, obtaining essential information such as accurate adsorption isotherms is crucial. This requirement, combined with often highly stringent production specifications, makes it challenging to identify even a feasible operating condition, let alone an optimal one. Trial-and-error-based approaches are often impractical as reaching cyclic steady state can be time-consuming, and any waste produced during this period can lead to significant economic losses. While rigorous dynamic models are available, they are computationally intensive and often do not accurately mirror actual process behavior. To address these challenges, the use of Bayesian Optimization (BO) is proposed to sequentially approach optimal SMB operation. Furthermore, it is suggested to employ the simpler True Moving Bed (TMB) model as a prior for the BO, which significantly accelerates convergence. This approach is demonstrated on an SMB process for cresol separation. Initially, the effectiveness of the BO using the TMB model is examined to gain insights into its behavior. Subsequently, we apply BO to the rigorous SMB model, informed by prior knowledge from the TMB model. Our results show that the developed BO framework rapidly converges to the optimal operating parameters that satisfy the purity constraints. We examine the efficiency improvements over various search algorithms and highlight the advantages of using the TMB model as a prior.

Triphenylamine-Based Covalent Organic Framework Films for Dopamine-Responsive Electrofluorochromism.

Covalent organic framework (COF) film with electrofluorochromic (EFC) and electrochromic (EC) properties has been synthesized by using triphenylamine-based monomers. The film exhibited a high maximum fluorescence contrast of 151 when subjected to a drive voltage of 0.75 V vs the Ag/AgCl electrode, causing the fluorescence to be quenched, which resulted in the EFC process's "fluorescence off" state. The switching times for the fluorescence on and off states were 0.51 and 7.79 s, respectively. Over the same voltage range, the COF film also displayed EC properties, achieving a contrast of 50.23% and a coloration efficiency of 297.4 cm2 C-1 at 532 nm, with switching times of 18.6 s for coloration and 0.7 s for bleaching. Notably, the quenched fluorescence of the COF film could be restored by adding dopamine as a reductant. This phenomenon enabled the implementation of a NAND logic gate using the applied potential as a physical input and dopamine addition as a chemical input. This study demonstrates the successful development of COF films with bifunctional EFC and EC properties, showcasing their potential for use in constructing advanced optoelectronic devices.

A Bayesian model to analyse the association of comorbidities with biosimilar treatment retention in a non-medical switch scenario in patients with inflammatory rheumatic musculoskeletal diseases

ObjectivesTo analyse clinical outcomes of a non-medical switch from originator adalimumab (ADA) to its ABP501 biosimilar (ABP) over 6 months in patients with inflammatory rheumatic musculoskeletal diseases (RMD) in relation to comorbidity as a risk factor for therapy discontinuation.MethodsRMD patients switching from originator ADA to ABP were identified from a large routine database from October 2018 onwards. Documented clinical data at the time of non-medical switching (baseline), and at 3 and 6 months were collected. Comorbidities were represented by the Charlson Comorbidity Index (CCI) at baseline and patients were categorized based on CCI > 0. Differences in the ABP retention rate over 6 months between patients with CCI = 0 and patients with CCI > 0 were analysed using Bayesian exponential regression.ResultsA total of 111 patients with axial spondyloarthritis (n = 68), rheumatoid arthritis (n = 23) and psoriatic arthritis (n = 15), were identified, 74.8% of whom had continued treatment with ABP after 6 months, while a smaller proportion had either switched to another ADA biosimilar (10.8%), switched back to originator ADA (7.2%), switched to a different biologic (3.6%), or dropped out (3.6%). At baseline, a CCI > 0 was found in 38% of patients. Cardiovascular comorbidities (40%) were most prevalent followed by diseases of the skin (33%), the gastrointestinal tract (20%) and the eye (20%). ABP treatment was continued after 6 months in 74% of patients with CCI = 0 and in 76% with CCI > 0. Bayesian analysis showed only a small difference (months) in the APB continuation rate between groups (estimate 0.0012, 95% credible interval (CrI) -0.0337 to 0.0361). Adjusting for age, sex, and disease subtype revealed somewhat shorter retention rates for patients with CCI > 0, but the distribution of the difference included 0 (estimate -0.0689, 95% CrI -0.2246 to 0.0234).ConclusionIn a non-medical switch scenario of RMD patients, there was no evidence for a considerable difference in ABP retention rates over 6 months between comorbidity groups.

Room temperature polariton spin switches based on Van der Waals superlattices

Transition-metal dichalcogenide monolayers possess large exciton binding energy and a robust valley degree of freedom, making them a viable platform for the development of spintronic devices capable of operating at room temperature. The development of such monolayer TMD-based spintronic devices requires strong spin-dependent interactions and effective spin transport. This can be achieved by employing exciton-polaritons. These hybrid light-matter states arising from the strong coupling of excitons and photons allow high-speed in-plane propagation and strong nonlinear interactions. Here, we demonstrate the operation of all-optical polariton spin switches by incorporating a WS2 superlattice into a planar microcavity. We demonstrate spin-anisotropic polariton nonlinear interactions in a WS2 superlattice at room temperature. As a proof-of-concept, we utilize these spin-dependent interactions to implement different spin switch geometries at ambient conditions, which show intrinsic sub-picosecond switching time and small footprint. Our findings offer new perspectives on manipulations of the polarization state in polaritonic systems and highlight the potential of atomically thin semiconductors for the development of next generation information processing devices.