Finesse measurement for high-power optical enhancement cavity

Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range(FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down(CRD) method, the rapidly swept-frequency(SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications.

Time-resolved measurement of atomic emission enhancement by fs-ns dual-pulsed laser-induced breakdown spectroscopy

Time-resolved measurement of atomic emission enhancement is performed by using a 500-fs KrF laser pulse incident upon a high density supersonic O2 gas jet, synchronized with an orthogonal ns frequency-doubled Nd：YAG laser pulse. The ultra-short pulse serves as an igniter of the gas jet, and the subsequent ns-laser pulse significantly enhances the atomic emission. Analysis shows that the contributions to the enhancement effect are made mainly by the bremsstrahlung radiation and cascade ionization.

Optimal decision-making method for equipment maintenance to enhance the resilience of power digital twin system under extreme disaster

Digital twins and the physical assets of electric power systems face the potential risk of data loss and monitoring failures owing to catastrophic events,causing surveillance and energy loss.This study aims to refine maintenance strategies for the monitoring of an electric power digital twin system post disasters.Initially,the research delineates the physical electric power system along with its digital counterpart and post-disaster restoration processes.Subsequently,it delves into communication and data processing mechanisms,specifically focusing on central data processing(CDP),communication routers(CRs),and phasor measurement units(PMUs),to re-establish an equipment recovery model based on these data transmission methodologies.Furthermore,it introduces a mathematical optimization model designed to enhance the digital twin system’s post-disaster monitoring efficacy by employing the branch-and-bound method for its resolution.The efficacy of the proposed model was corroborated by analyzing an IEEE-14 system.The findings suggest that the proposed branch-and-bound algorithm significantly augments the observational capabilities of a power system with limited resources,thereby bolstering its stability and emergency response mechanisms.

Optimizing outcomes:Implementing enhanced recovery after surgery in orthopedic surgery

In the realm of orthopedics,the adoption of enhanced recovery after surgery(ERAS)protocols marks a significant stride towards enhancing patient well-being.By embracing a holistic approach that encompasses preoperative counseling,dietary optimization,minimally invasive procedures,and early postoperative mobilization,these protocols have ushered in a new era of surgical care.Despite encountering hurdles like resistance to change and resource allocation challenges,the efficacy of ERAS protocols in improving clinical outcomes is undeniable.Noteworthy benefits include shortened hospital stays and bolstered improved patient-safety measures.Looking ahead,the horizon for ERAS in orthopedics appears bright,with an emphasis on tailoring care to individual needs,integrating cutting-edge technologies,and perpetuating research endeavors.This shift towards a more personalized,streamlined,and cost-efficient model of care underscores the transformative potential of ERAS in reshaping not only orthopedic surgery but also the journey to patient recovery.This editorial details the scope and future of ERAS in the orthopedic specialty.

Application of Quantum Sensing Technology in Power System Measurements

The accuracy of power system measurements directly affects the safe and stable operation of power grids. This study explores the application prospects of quantum sensing technology in power system measurements. The research first analyzes the limitations of traditional measurement techniques, such as electromagnetic interference sensitivity and measurement accuracy bottlenecks. It then introduces the basic principles of quantum sensing, including concepts like quantum entanglement and superposition states. Through theoretical analysis and numerical simulations, the study assesses the potential advantages of quantum sensors in current, voltage, and magnetic field measurements. Results show that quantum magnetometers offer significant improvements in accuracy and interference resistance for current measurements. The study also discusses the application of quantum optical technology in high-voltage measurements, demonstrating its unique advantages in improving measurement dynamic range. However, quantum sensing technology still faces challenges in practical applications, such as technological maturity and cost. To address these issues, the research proposes a phased implementation strategy and industry-academia collaboration model. Finally, the study envisions future directions combining quantum sensing with artificial intelligence. This research provides a theoretical foundation for innovative upgrades in power system measurement technology.

Enhanced recovery after surgery:Current research insights and future direction

Since the concept of enhanced recovery after surgery(ERAS)was introduced in the late 1990 s the idea of implementing specific interventions throughout the perioperative period to improve patient recovery has been proven to be beneficial. Minimally invasive surgery is an integral component to ERAS and has dramatically improved post-operative outcomes. ERAS can be applicable to all surgical specialties with the core generic principles used together with added specialty specific interventions to allow for a comprehensive protocol,leading to improved clinical outcomes. Diffusion of ERAS into mainstream practice has been hindered due to minimal evidence to support individual facets and lack of method for monitoring and encouraging compliance. No single outcome measure fully captures recovery after surgery,rather multiple measures are necessary at each stage. More recently the pre-operative period has been the target of a number of strategies to improve clinical outcomes,described as prehabilitation. Innovation of technology in the surgical setting is also providing opportunities to overcome the challenges within ERAS,e.g.,the use of wearable activity monitors to record information and provide feedback and motivation to patients peri-operatively. Both modernising ERAS and providing evidence for key strategies across specialties will ultimately lead to better,more reliable patient outcomes.

Perioperative nursing principles guided by the concept of enhanced recovery after surgery

Objective:To explore the clinical effect of perioperative nursing guided by the concept of enhanced recovery after surgery and summarize them.Methods:Pubmed,Chinese National Knowledge Infrastructure(CNKI),Chinese Biomedical Literature Database(CBM),Wanfang Database,and VIP Database were searched to obtain the relevant literature involving enhanced recovery after surgery(ERAS)guidance,obtain the effective clinical data,review the reports in literature,and obtain the effective scheme.Results:Compared with the traditional nursing program,perioperative nursing principles guided by the concept of ERAS provide more accurate nursing care to patients and reduce the occurrence of intraoperative stress events through comprehensive nursing measures such as preoperative pre-rehabilitation measures,intraoperative body temperature and fluid management,postoperative analgesia,prevention of nausea and vomiting,early mobilization,catheter nursing,and better out-of-hospital follow-up.Conclusions:Perioperative nursing principles guided by the concept of ERAS can significantly reduce the incidence of perioperative complications,shorten the hospital stay of patients,and promote postoperative rehabilitation of patients.The transformation and implementation of this concept can bring significant benefits to hospitals,medical care,and patients.

Single-Channel Speech Enhancement Using Critical-Band Rate Scale Based Improved Multi-Band Spectral Subtraction

This paper addresses the problem of single-channel speech enhancement in the adverse environment. The critical-band rate scale based on improved multi-band spectral subtraction is investigated in this study for enhancement of single-channel speech. In this work, the whole speech spectrum is divided into different non-uniformly spaced frequency bands in accordance with the critical-band rate scale of the psycho-acoustic model and the spectral over-subtraction is carried-out separately in each band. In addition, for the estimation of the noise from each band, the adaptive noise estimation approach is used and does not require explicit speech silence detection. The noise is estimated and updated by adaptively smoothing the noisy signal power in each band. The smoothing parameter is controlled by a-posteriori signal-to-noise ratio (SNR). For the performance analysis of the proposed algorithm, the objective measures, such as, SNR, segmental SNR, and perceptual evaluations of the speech quality are conducted for the variety of noises at different levels of SNRs. The speech spectrogram and objective evaluations of the proposed algorithm are compared with other standard speech enhancement algorithms and proved that the musical structure of the remnant noise and background noise is better suppressed by the proposed algorithm.

Characteristics and Electrical Properties of SiNx:H Films Fabricated by Plasma-Enhanced Chemical Vapor Deposition

SiNx：H films with different N/Si ratios are synthesized by plasma-enhanced chemical vapor deposition （PECVD）. Composition and structure characteristics are detected by Fourier transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）. It indicates that Si-N bonds increase with increased NH3/SiH4 ratio. Electrical property investigations by I-V measurements show that the prepared films offer higher resistivity and less leakage current with increased N/Si ratio and exhibit entirely insulating properties when N/Si ratio reaches 0.9, which is ascribed to increased Si-N bonds achieved.

（Dis）Economies of Scale in Business Software Systems Development and Enhancement Projects

In the software engineering literature, it is commonly believed that economies of scale do not occur in case of software Development and Enhancement Projects （D＆EP）. Their per-unit cost does not decrease but increase with the growth of such projects product size. Thus this is diseconomies of scale that occur in them. The significance of this phenomenon results from the fact that it is commonly considered to be one of the fundamental objective causes of their low effectiveness. This is of particular significance with regard to Business Software Systems （BSS） D＆EP characterized by exceptionally low effectiveness comparing to other software D＆EP. Thus the paper aims at answering the following two questions： （1） Do economies of scale really not occur in BSS D＆EP？ （2） If economies of scale may occur in BSS D＆EP, what factors are then promoting them？ These issues classify into economics problems of software engineering research and practice.

Time-resolution enhanced multi-path OTD measurement using an adaptive filter based incoherent OFDR

High accuracy and time resolution optical transfer delay(OTD)measurement is highly desired in many multi-path applications,such as optical true-time-delay-based array systems and distributed optical sensors.However,the time resolution is usually limited by the frequency range of the probe signal in frequency-multiplexed OTD measurement techniques.Here,we proposed a time-resolution enhanced OTD measurement method based on incoherent optical frequency domain reflectometry(I-OFDR),where an adaptive filter is designed to suppress the spectral leakage from other paths to break the resolution limitation.A weighted least square(WLS)cost function is first established,and then an iteration approach is used to minimize the cost function.Finally,the appropriate filter parameter is obtained according to the convergence results.In a proof-of-concept experiment,the time-domain response of two optical links with a length difference of 900 ps is successfully estimated by applying a probe signal with a bandwidth of 400 MHz.The time resolution is improved by 2.78times compared to the theoretical resolution limit of the inverse discrete Fourier transform(iDFT)algorithm.In addition,the OTD measurement error is below±0.8 ps.The proposed algorithm provides a novel way to improve the measurement resolution without applying a probe signal with a large bandwidth,avoiding measurement errors induced by the dispersion effect.

Scattering Centers Measurements by a Modified MEMP Method

A modified matrix enhancement and matrix pencil (MMEMP) method is presented for the scattering centers measurements in step-frequency radar. The method estimates the signal parameter pairs directly unlike the matrix enhancement and matrix pencil (MEMP) method which contains an additional step to pair the parameters related to each dimension. The downrange and crossrange expressions of the scattering centers are deduced, as well as the range ambiguities, from the point of view of MMEMP method. Compared with the Fourier transform method, the numerical simulation shows that both the resolution and precision of the MMEMP method are higher than those of the Fourier method. The processing results of the real measured data for three cylinders prove the above conclusions further.

Utilization of Extrinsic Fabry-Perot Interferometers with Spectral Interferometric Interrogation for Microdisplacement Measurement

The paper presents a number of signal processing approaches for the spectral interferometric interrogation of extrinsic Fabry-Perot interferometers(EFPIs). The analysis of attainable microdisplacement resolution is performed and the analytical equations describing the dependence of resolution on parameters of the interrogation setup are derived. The efficiency of the proposed signal processing approaches and the validity of analytical derivations are supported by experiments. The proposed approaches allow the interrogation of up to four multiplexed sensors with attained resolution between 30 pm and 80 pm, up to three times improvement of microdisplacement resolution of a single sensor by means of using the reference interferometer and noisecompensating approach, and ability to register signals with frequencies up to 1 kHz in the case of 1 Hz spectrum acquisition rate. The proposed approaches can be used for various applications, including biomedical, industrial inspection, and others, amongst the microdisplacement measurement.

Analysis of Software Development and Enhancement Projects Work Effort per Unit Based on the COSMIC Method with Regard to Technological Factors—Case Study

This paper aims to present a case study that consists in the analysis of work effort per unit of software systems Development and Enhancement Projects (D&EP) depending on technological factors. That analysis was commissioned by one of the largest public institutions in Poland. This is the COSMIC (Common Software Measurement International Consortium) function points method that is chosen by this institution as a point of reference for size of software systems developed/enhanced for supporting its functions and therefore this method is the base for the analysis of D&EP work effort per unit with regard to technological factors.

Spatio-temporal measures of electrophysiological correlates for behavioral multisensory enhancement during visual,auditory and somatosensory stimulation:A behavioral and ERP study

Multisensory enhancement,as a facilitation phenomenon,is responsible for superior behavioral performance when an individual is responding to cross-modal versus modality-specific stimuli.However,the event-related potential（ERP） counterparts of behavioral multisensory enhancement are not well known.We recorded ERPs and behavioral data from 14 healthy volunteers with three types of target stimuli（modality-specific,bimodal,and trimodal） to examine the spatio-temporal electrophysiological characteristics of multisensory enhancement by comparing behavioral data with ERPs.We found a strong correlation between P3 latency and behavioral performance in terms of reaction time（RT）（R = 0.98,P ＆lt;0.001）,suggesting that P3 latency constitutes a temporal measure of behavioral multisensory enhancement.In addition,a fast RT and short P3 latency were found when comparing the modality-specific visual target with the modality-specific auditory and somatosensory targets.Our results indicate that behavioral multisensory enhancement can be identified by the latency and source distribution of the P3 component.These findings may advance our understanding of the neuronal mechanisms of multisensory enhancement.

Enhancement of the angular rotation measurement sensitivity based on SU(2)and SU(1,1) interferometers

We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam with a vacuum beam in an SU(2) interferometer, we get the sensitivity of the angular rotation measurement as 1/(2N^(1/2)l). We can surpass the limit of the angular rotation measurement in an SU(1,1) interferometer by combining a coherent beam with a vacuum beam or a squeezed vacuum beam when the probe beam has OAM. Without injection, the sensitivity can reach 1/(2N^(1/2)l). In addition, by employing another construction of an SU(1,1) interferometer where the pump beam has OAM, with the same injection of an SU(1,1) interferometer, the sensitivity of the angular rotation measurement can be improved by a factor of 2, reaching 1/(4Nl). The results confirm the potential of this technology for precision measurements in angular rotation measurements.

大直径盾构隧道纵向刚度增强措施研究

为研究不同环缝接头结构对盾构隧道纵向刚度的增强效果,采用等效连续化模型计算得到断面直径对隧道纵向拉压、纵向抗剪和纵向抗弯刚度的影响规律,将隧道纵向刚度增强措施与管片环缝接头结构相联系,采用数值模拟深入探究了9种环缝接头结构的力学性能,对比得到增强隧道纵向刚度效果最优的环缝接头结构。结果表明:直径对纵向拉压和纵向抗弯刚度影响较小,对纵向抗剪刚度影响较大;环缝接头刚度增强措施能够显著减小管片位移,提高隧道纵向刚度,提升效果为:斜螺栓>弯螺栓,定位榫>剪力销>凹凸榫;螺栓型式和纵向刚度增强措施均对螺栓最大剪切应力有较大影响,竖向荷载下受螺栓型式影响较大,水平向荷载下受管片环缝接头刚度增强措施影响较大;结合经济性和有效性,当接头螺栓为弯螺栓时,设置定位榫是一种相对较优的选择。

基于图结构增强的图神经网络方法

针对图卷积网络(GCNs)在面对低同质性的图结构时性能骤降问题,提出了一种新颖的基于图结构增强的图神经网络方法,用于学习改善的图节点表示。首先将节点信息通过消息传播和聚合,得到节点的初始表示;然后计算节点表示的相似性度量,得到图的同质结构;最后融合图的原始结构和同质结构进行节点的信息传递得到节点表示用于下游任务。结果表明:在6个公开的数据集上,所提算法在节点分类的多个指标上均优于对比算法,特别是在同质性较低的4个数据集上,所提算法的准确度(ACC)分数分别超过最高基准5.53%、6.87%、3.08%、4.00%,宏平均(F1)值分别超过最高基准5.75%、8.06%、6.46%、5.61%,获得了远高于基准的优越表现,表明所提方法成功改善了图数据的结构,验证了该算法对图结构优化的有效性。

瓜类作物对盐胁迫的响应及其耐盐性增强措施研究进展

盐胁迫是影响瓜类作物生长发育和产量的主要非生物因素之一。本研究综述了盐胁迫对瓜类作物生长发育及生理的影响,总结了外源物质、耐盐品种选育、生物诱导、嫁接等耐盐性增强措施对瓜类作物盐胁迫的缓解效应及机制,同时对瓜类作物耐盐性增强措施的发展方向进行了展望,以期为盐渍土环境下瓜类作物的产量增加和品质提升提供依据。

RIS辅助的无线通信:原型验证与实测进展

智能超表面(reconfigurable intelligent surface,RIS)具备以低功耗、低成本提升通信传输速率的特点,被视为6G的关键技术之一,近年来受到广泛关注。综述了RIS辅助的无线通信系统的信道测量进展,介绍了时域和频域测量系统的大致原理,并对大尺度衰落模型、小尺度衰落模型和信道互易性的原型验证工作进行了总结。进而,综述了RIS硬件特性方面的测量进展,分析了有源RIS以及RIS的功耗、比特数和极化等特性。此外,总结了RIS覆盖增强的测量进展,介绍了RIS的部署位置、相位设计和信道的有效秩对覆盖增强性能的影响。最后,展望了RIS辅助无线通信原型验证与实际测量的未来研究方向和可能面临的挑战。