Effect Of Mismatch Research Articles

Insight into Optimally Noise- and Signal-Matched Three-Stage LNAs and Effect of Inter-Stage Mismatch

This manuscript provides insight into optimally noise-matched three-stage Low-Noise Amplifiers (LNAs) by proposing a novel chart that illustrates the relationship between the gain of a three-stage LNA and inter-stage mismatch levels. Under certain conditions, the chart also indicates the required feedback inductor values for all transistors. It is demonstrated that, under the specific assumption of optimal noise and signal matching, the LNA gain depends on the levels of two inter-stage mismatches. Contrary to common belief, the results show that the LNA gain increases as the inter-stage mismatch levels rise. This finding is supported through the discussion of two LNA designs, one with lower and one with higher inter-stage mismatch levels, achieving gains of 24 dB and 26 dB, respectively, with a Noise Figure of 1.7 dB at the center design frequency of 28 GHz. Subsequently, one LNA topology is validated in a Monolithic Microwave Integrated Circuit (MMIC) implementation using WIN Foundry’s PIH1-10 GaAs E-mode technology. The MMIC characterization aligns with the simulated behavior, accounting for the unavoidable losses in the matching networks.

Sensorless control of PMSM based on new cascade MRAS

ABSTRACT Various operational factors, such as temperature, load, and magnetic saturation, influence the permanent magnet synchronous motor (PMSM) and cause stator resistance, stator inductance, and rotor flux linkage fluctuations. These variations result in decreased accuracy under vector control and the problem of inaccurate position estimation under speed sensorless control. This paper proposes a new method using a cascaded model reference adaptive system (MRAS) to identify the rotor speed and three motor parameters. The adaptive law is improved by employing Popov’s super stability theorem and combining a fuzzy adaptive control algorithm. The resulting identification outcomes are incorporated into the control system to enhance control. Finally, the simulation results demonstrate that the proposed method can address the issue of model under-ranking and mitigate the effect of motor parameter mismatch on FOC control through theoretical analysis and simulations using MATLAB/Simulink software. This approach enhances dynamic tracking and robustness while holding significant engineering importance.

The effect of gender (mis)match on the interpretation of English reflexive pronouns in cases of VP-ellipsis by native and non-native speakers of English

This paper aims to investigate the effect of both gender (mis)match and the direction of the gender mismatch on the interpretation of English reflexive pronouns in cases of VP-ellipsis by native speakers of English and L1 Spanish learners of English with different proficiency levels (intermediate, upper intermediate and advanced). Results showed that native speakers of English tend to prefer the sloppy reading over the strict one and are sensitive to gender mismatches when interpreting reflexives in VP-ellipsis constructions. Our data support a non-structural account of ellipsis resolution. Concerning learners, no gender mismatch effects were attested, since, in general, their preferred choice of sloppy interpretations was less frequent in both matched and mismatched contexts. Nevertheless, proficiency turned out to be a significant factor in the interpretation of gender-matched sentences, as intermediate learners interpreted the experimental sentences sloppily significantly less frequently than native speakers, whilst advanced learners did not. Finally, all participants showed a more marked preference for sloppy readings in feminine-masculine orderings.

The Effects of Student–Teacher Ethnoracial Matching on Chronic Absenteeism: Exploring the Role of Relational Dynamics in Early Education

ABSTRACT Research Findings: The current study examines the relationship between student–teacher ethnoracial matching and chronic absenteeism in early elementary grades and evaluates whether this relationship is moderated by Closeness and Conflict in student–teacher relationships, using data from the Early Childhood Longitudinal Study for Kindergarten class of 2011 (ECLSK:2011). Significant ethnoracial matching effects on chronic absenteeism likelihood were found. Teachers reported varying levels of Conflict and Closeness in their relationships with students, differing by race and ethnicity. Critically, higher levels of Closeness buffered the adverse effects of ethnoracial mismatch on chronic absenteeism, suggesting that positive relationships can serve as a protective factor against absenteeism in ethnoracially mismatched contexts. Practice or Policy: The findings emphasize the importance of fostering inclusive and supportive school environments. Specifically, increasing teacher awareness and sensitivity toward ethnoracial differences can help strengthing student-teacher relationships, thereby improving student attendance. Policymakers and educators should prioritize initiatives such as professional development and diversity training to improve teacher responsiveness to ethnoracial dynamics. Enhancing Closeness and reducing Conflict in student–teacher relationships may be key to improving attendance and academic outcomes, especially for students from historically marginalized groups.

Association of HLA Mismatch With Adverse Cardiovascular Events Following Lung Transplantation: A Single-Center Study.

Coronary artery disease (CAD) is a frequent comorbidity in lung transplant (LuTx) candidates. The impact of allogenic organ transplantation and the corresponding alterations in immune response on the progression of CAD remains poorly understood. In this study, we sought to analyze the effect of donor-recipient overall human leukocyte antigen (HLA) and HLA-DQ mismatch on cardiovascular outcomes following LuTx. This retrospective analysis of adult patients receiving lung transplantation at the LMU University Hospital between 2012 and 2018 included 310 patients, the majority of whom (67.4%) had undergone double lung transplantation. There were no significant differences in the incidence of the primary composite endpoint between patients with high/low HLA mismatches (22 [7.9%] vs. 4 [12.9%]; p=0.311). Numerically higher rates of the primary endpoint, myocardial infarction, and cardiovascular death in the low HLA mismatch group can partially be explained by differences in baseline rates of CAD and coronary sclerosis. Notably, neither HLA-DQ mismatch nor the occurrence of rejection episodes or cytomegalovirus (CMV) infection was associated with the occurrence of cardiovascular events following transplantation. In this study cohort, high HLA mismatch and HLA-DQ mismatch were not associated with increased adverse cardiovascular events. Furthermore, neither transplant rejection nor CMV infection increased the risk for cardiovascular events. The high cardiovascular event rates following LuTx necessitate meticulous cardiovascular follow-up, irrespective of immunological matching.

Effect of Ethnic Mismatch on Survival After Lung Transplantation

Effect of Ethnic Mismatch on Survival After Lung Transplantation

Influence of Green Credit Policy on Corporate Risk-Taking: The Mediating Effect of Debt Maturity Mismatch and the Moderating Effect of Executive Compensation

Risk-taking is a critical driver of sustainable development and financial performance for firms, especially under environmental degradation constraints. Despite the increasing implementation of green credit policies, their impact on corporate risk-taking remains underexplored in the existing literature. This study investigates the effects and underlying mechanisms of green credit policies on risk-taking behaviors among Chinese listed companies from 2009 to 2019. Utilizing econometric methodologies, including Difference-in-Differences, mediation analysis, and moderation analysis, the findings reveal that green credit policies significantly enhance the risk-taking activities of polluting enterprises. These results are robust across various sensitivity tests. Additionally, the relationship between green credit policies and corporate risk-taking is mediated by debt maturity mismatch and moderated by ESG and executive compensation. Subgroup analyses indicate that large and state-owned polluting enterprises experience greater increases in risk-taking compared to their small, medium-sized, and private counterparts. Furthermore, executive remuneration notably amplifies risk-taking in private firms. This research provides essential micro-level insights to optimize the effectiveness of green credit policies in promoting corporate risk-taking and advancing sustainable development.

Composition-controlled recovery time of SWIR (2-2.4 µm) GaSb-based SESAMs.

SEmiconductor Saturable Absorber Mirrors (SESAMs) have revolutionized the ultrafast laser industry. While SESAMs are well-established in the near-infrared regime, using GaAs-wafer epitaxy, there is an increasing interest for the short-wave infrared (SWIR) regime, for which SESAMs can be fabricated using the GaSb material system. Compared to GaAs-based SESAMs, the nonlinear response of GaSb absorbers has been reported to exhibit inherent ultrafast response and a different interplay between the response time and fabrication process. Here we report new advanced features of this interplay in a detailed study investigating the effects of lattice mismatch (LMM, e.g., strain) in the quantum wells (QWs), and barrier materials of SESAMs designed for a center wavelength between 2 and 2.4 µm. At 2 μm, SESAMs with ternary InGaSb, GaAsSb, and quaternary In(x)Ga(1-x)As(y)Sb(1-y) QWs embedded in GaSb were grown with varying levels of QW LMM, ranging from compressive strain (-1.7% LMM) to tensile strain (+0.9% LMM). We observed a strong dependence of the recovery time on the QW strain. While a maximum interband recovery time of 340 ps was measured for lattice matched QWs (-0.1% LMM), both compressively and tensilely strained QWs exhibit a shorter interband recovery time. Furthermore, a set of In0.27GaSb QW SESAMs embedded in AlxGa1-xAsSb barriers with different Al content have been grown. We observed that an increasing Al content in the barrier significantly slows down the interband recovery time. All findings are consistent for different heterostructures designed for operation at 2-2.4 µm.

Study on the Influence of Hygrothermal Aging on the Mechanical Properties of Carbon Fabric/Polyetheretherketone Composites.

Owing to its superior mechanical properties and recyclability, the carbon fabric/polyetheretherketone (CFF/PEEK) composite has seen increasing application in engineering domains. However, studies examining the impact of hygrothermal aging on its performance remain relatively limited in the existing literature. To investigate its durability in hygrothermal environments, this study fabricated CFF/PEEK composites with a fiber volume fraction of 55 vol% and subjected them to equilibrium hygroscopic treatment at 70 °C. The hygroscopic behavior of polyetheretherketone (PEEK) resin and CFF/PEEK composites, along with their tensile and compressive properties under dry conditions at room temperature (RTD) and wet conditions at 70 °C (ETW), were systematically evaluated. The results indicated that both PEEK resin and CFF/PEEK composites exhibited Fickian diffusion behavior during the initial stages of aging but diverged in later stages. The equilibrium moisture absorption rates were approximately 0.32% for PEEK resin and 0.19% for CFF/PEEK composites. After aging at 70 °C, the strength of both materials decreased significantly, while the modulus showed only minor changes. Under ETW conditions, the tensile strength retention rate of PEEK resin was 74.92%, and the compressive strength retention rate was 81.85%. For the CFF/PEEK composites, the tensile strength retention rate was approximately 85%, and the compressive strength retention rate was about 95%. The typical failure modes of CFF/PEEK composites did not exhibit notable differences between tensile and compressive specimens after hygrothermal aging. Resin debonding was observed in the moisture-absorbed composite specimens, while no microcracks or delamination were detected. The degradation of mechanical properties is predominantly attributed to the deterioration of the resin matrix and interface characteristics, which are caused by water molecule intrusion and the adverse effects of wet strain mismatch between the resin and fibers.

Thermoelastic behavior analysis of finite composites embedded in ellipsoidal inhomogeneities with inclusion-based boundary element method

Thermoelastic behavior analysis of finite composites embedded in ellipsoidal inhomogeneities with inclusion-based boundary element method

Event conflation in high stakes testing: a comparison of usage and relationship to writing scores by language types

Abstract Talmy (1985. Lexicalization patterns: Semantic structure in lexical form. In Timothy Shopen (ed.), Language typology and syntactic description, vol. 3, 36–149. Cambridge, MA: Cambridge University Press, 1991. Path to realization: A typology of event conflation. In Proceedings of the 17th annual meeting of the Berkeley Linguistics Society, 480–519. Berkeley Linguistics Society) introduced the concept of event conflation: that two micro events can be conceptualized and expressed as a single macro event. He proposed a linguistic typology based on this concept, and second language acquisition studies have suggested that learners whose first language is of a different type than their target language have extra difficulty interpreting and reproducing event conflation in the target language phrases. However, the degree to which using conflation patterns similar to the first language in one’s target language impedes communication is still unclear. To observe the effect of first and second language type mismatches on communicative ability, data was taken from the independent writing task of the TOEFL iBT® Public Use Dataset and the Event Conflation Finder was used to extract and analyze instances of path encoding. Framing tendencies and correlations between these tendencies and rater scores were compared amongst learners whose first languages are often argued to be one of the three major types: satellite-framed, mixed-framed, and verb-framed. I found that only learners with verb-framed first languages exhibited a clear pattern of correlation between typical satellite-framing patterns and rater scores, suggesting that satellite-framed expressions are more difficult for learners whose first language is verb-framed.

Implant Size Versus Mastectomy Weight in Breast Reconstruction: Does Matching Matter?

During nipple-sparing mastectomy with direct-to-implant based breast reconstruction, if the size of the chosen implant is smaller than the mastectomy specimen, a volumetric mismatch occurs creating dead space. This study evaluates the effect of volumetric mismatch between chosen implant size and mastectomy weight on postoperative complications after breast reconstruction. A multicenter retrospective cohort study was conducted on patients undergoing nipple-sparing mastectomy with direct-to-implant based breast reconstruction. The effect of volumetric mismatch [mastectomy weight (g) - implant size (mL)] on postoperative complications were evaluated using receiver operating characteristic analysis and multivariable regression analyses. A total of 1617 breast reconstructions were performed in 1031 patients. The mean mastectomy weight was 442.6 g (±219.1), the mean implant size was 403.2 mL (±152.0) and the mean volumetric mismatch was 37.1 (±108.2). The mean follow-up was 25.3 months (±15.2). Total complication rate was 8.3%. A volumetric mismatch of ≥78 was associated with increased complications when controlled for mastectomy weight and implant size, with higher rates of any complication (14.6% vs 6.4%, P < 0.0001), explantation due to infection (2.9% vs 1.1%, P = 0.05), infection (4.5% vs 1.6%, P = 0.01), and seroma (6.9% vs 1.9%, P < 0.0001). On multivariable regression for any complication, volumetric mismatch [odds ratio 1.9 (95% CI 1.0-3.4) P = 0.043], smoking and age were significant predictors. A greater mismatch between implant size and mastectomy weight was a significant predictor of postoperative complications, including explantation. Knowing this, surgeons may choose to match implant size more evenly to mastectomy weight, opt for skin sparing mastectomies or consider operative techniques to minimize dead space.

Adaptive phase-field modeling of fracture propagation in layered media: Effects of mechanical property mismatches, layer thickness, and interface strength

Adaptive phase-field modeling of fracture propagation in layered media: Effects of mechanical property mismatches, layer thickness, and interface strength

A Computational Study on the Neck-Stem Rectangular Tapered Connection: Effects of Angular Mismatch, Assembly, and Cyclic Loading.

The bi-modular hip prosthesis is characterized by two tapered connections: a circular cross-section at the head-neck interface and a rectangular cross-section at the neck-stem interface. Even if the latter guarantees customization, it concerns a high rate of early failure. The connection resistance is relatable to machining (tolerances cause angular mismatch), implantation (hammering force or manual), and usage (Body Mass Index [BMI]). Due to the lack of literature about the neck-stem coupling, this work aims to investigate how the geometry of the rectangular taper connection and the external loads affect the fatigue strength of a bi-modular hip prosthesis through a 3D Finite Element Model (FEM). Nine combinations of neck-stem coupling are obtained considering the tolerances' limits on frontal and lateral angles as . The CoCr neck and the Ti6Al4V stem, studied in their halved, are constrained and loaded inspired by the standard ISO 7206: the stem is distally encastered simulating the embedding and tilted by 10° concerning the sagittal plane, while the force is applied vertically. First, the influence of the assembly is investigated using , , and ; then, a cyclical vertical force varying from to is imposed. Finally, one combination is analyzed in its integrity to evaluate the effect of the out-of-plane load. The study's findings concern: (i) a positive angular mismatch, which is responsible for proximal contacts, improves fatigue life, reducing Sines stress up to 33%; (ii) the higher the assembly force the higher the neck stability and the lower the extension of the overstressed lateral area; (iii) the implant fatigue resistance is directly proportional to the patient's BMI; and (iv) the out-of-plane external load causes a 40% increment in the fatigue failure risk.

Effects of Interaural Latency and Frequency Mismatch on Speech Recognition for Bimodal Cochlear Implant Users.

Bimodal cochlear implant (CI) users vary in speech recognition outcomes. This variability may be influenced partly by the CI and contralateral hearing aid (HA) programming procedures, which can result in mismatches in latency and frequency. We assessed the performance of bimodal listeners when latency mismatches were corrected and analyzed how frequency mismatches influenced outcomes. Twelve adults with at least 1 year of bimodal use were evaluated in latency mismatched versus matched conditions. Masked sentence recognition was assessed in a 10-talker masker for three spatial configurations: target from the front and the masker either co-located, 90° toward the CI-ear, or 90° toward the HA-ear. Frequency mismatch for the most apical electrode (E1) was determined from postoperative imaging and the filter frequency assignment of their familiar CI map. Participants had significantly better performance when latency mismatches were small or matched between the devices, with an approximately 10% improvement in the configuration with the masker toward the HA-ear. Significantly, poorer performance was observed with larger magnitudes of frequency mismatch, with a 2% drop in performance for every one semitone deviation increase in mismatch. The interaction between latency and frequency mismatch was nonsignificant, suggesting that the benefit of latency matching was approximately additive across the range of frequency mismatches. Detrimental effects of interaural mismatches in latency and frequency were observed, even after long-term device use. These preliminary results suggest that bimodal CI users might benefit from individualized fitting procedures that match latency across devices and minimize frequency mismatch for the CI. 3 Laryngoscope, 2025.

Dragon Intermittency at the Transition to Synchronization in Coupled Rulkov Neurons

We investigate the synchronization dynamics of two non-identical, mutually coupled Rulkov neurons, emphasizing the effects of coupling strength and parameter mismatch on the system’s behavior. At low coupling strengths, the system exhibits multistability, characterized by the coexistence of three distinct 3-cycles. As the coupling strength is increased, the system becomes monostable with a single 3-cycle remaining as the sole attractor. A further increase in the coupling strength leads to chaos, which we identify as arising through a novel type of intermittency. This intermittency is characterized by alternating dynamics between two low-dimensional invariant subspaces: one corresponding to synchronization and the other to asynchronous behavior. We show that the system’s phase-space trajectory spends variable durations near one subspace before being repelled into the other, revealing non-trivial statistical properties near the onset of intermittency. Specifically, we find two key power-law scalings: (i) the mean duration of the synchronization interval scales with the coupling parameter, exhibiting a critical exponent of −0.5 near the onset of intermittency, and (ii) the probability distribution of synchronization interval durations follows a power law with an exponent of −1.7 for short synchronization intervals. Intriguingly, for each fixed coupling strength and parameter mismatch, there exists a most probable super-long synchronization interval, which decreases as either parameter is increased. We term this phenomenon “dragon intermittency” due to the distinctive dragon-like shape of the probability distribution of synchronization interval durations.

Modification of Liposomal Properties by an Engineered Gemini Surfactant.

Lipid membranes form the primary structure of cell membranes and serve as configurable interfaces across numerous applications including biosensing technologies, antifungal treatments, and therapeutic platforms. Therefore, the modification of lipid membranes by additives has important consequences in both biological processes and practical applications. In this study, we investigated a nicotinic-acid-based gemini surfactant (NAGS) as a chemically tunable molecular additive for modulating the structure and phase behavior of liposomal membranes. We specifically focused on NAGS with hydrocarbon chains that mirror those of lipid molecules. By introducing NAGS to phosphatidylcholine membranes with lipids of identical and varied chain lengths or degrees of unsaturation, we demonstrated the effects of headgroup interactions and chain mismatch between NAGS and membrane lipids. Using small-angle X-ray scattering, we showed that regardless of chain compatibility or mismatch, NAGS reduced the thickness and packing density of fluid lipid membranes. Further observations by fluorescence microscopy revealed the emergence of ordered-disordered domains upon cooling to room temperature. The observed phases were quite distinct from those of lipid membranes with analogous chain compositions, emphasizing the importance of NAGS headgroup chemistry in mediating domain formation and stabilization. These findings open new possibilities for exploiting NAGS in tuning the structure and organization of liposomal membranes with potential applications in drug delivery and biomedical imaging.

Fast iterative position estimation method of permanent magnet synchronous linear motor

Abstract In this paper, a Fast Iterative Phase Estimation (FIPE) algorithm is proposed for robotic grinding force control devices using Permanent Magnet Synchronous Linear Motors (PMSLM), requiring high positional accuracy and response speed. FIPE obtains optimal phase estimates through iterative searching and exhibit excellent dynamic performance. The proposed method is optimized by iterative optimization algorithms, which significantly reduces the number of iterations and enhance the response speed of position estimation. In addition, the effects of harmonics, amplitude mismatch, noise and DC errors in the raw signal on the FIPE algorithm are discussed, and a shallow neural network is introduced to compensate the periodic errors. The experimental results show that the FIPE algorithm has higher calculation accuracy and dynamic performance than the traditional PLL such as SRF-PLL, ANF-PLL and LKF-PLL, and has faster iteration speed than the traditional position estimator such as FPS-PLL.

Dynamic Decoupled Current Control for Smooth Torque of the Open-Winding Variable Flux Reluctance Motor Using Integrated Torque Harmonic Extended State Observer

Variable Flux Reluctance Machines (VFRMs) face multiple interconnected challenges that limit their performance, particularly in high-performance applications such as electric vehicles (EVs), where smooth torque output and robust operation are critical. Chief among these challenges are complex inter-axis couplings, including cross-coupling in the dq-axis, differential term coupling in the d0-axis, and disturbances propagating from the 0-axis to the q-axis. Additionally, harmonic disturbances associated with torque ripple exacerbate performance issues, resulting in degraded dynamic behavior. These challenges hinder current loop controllers, preventing effective management of winding impedance voltage drops and inter-axis coupling terms without advanced decoupling strategies. To address these challenges, this paper proposes a novel integrated torque harmonic extended state observer (ITHESO) within a decoupled current control designed to ensure fast and accurate current tracking, system stability, and torque ripple reduction. The ITHESO identifies and compensates for total current disturbances, including harmonic components, through feed-forward compensation within the current loop. Furthermore, the influence of control parameters and the effects of parameter mismatches on stability, torque ripple reduction, and disturbance rejection are thoroughly analyzed. Experimental validations demonstrate that the proposed strategy significantly enhances torque dynamics and reduces torque ripple, outperforming the conventional Active Disturbance Rejection Control (ADRC), which does not explicitly address disturbances associated with torque ripple. These advancements position the VFRM with the ITHESO as a competitive option for high-performance EV propulsion systems, offering smooth operation, noise reduction, and reliable performance under varying speeds and loads.

Effects of interfacial debonding of microspheres on mechanical properties of iron matrix syntactic foams: Roles of Ni coating

Effects of interfacial debonding of microspheres on mechanical properties of iron matrix syntactic foams were investigated through experimental and numerical analyses. Glass microspheres with and without Ni layers were used for dealing with different interfacial bonding states, where the layers increased strength 1.6 times higher than the non-layered syntactic foams. Numerical models estimated stress concentration and early evolution of plastic strain under tension, leading to greater degradation of properties by debonding compared to those under compression. Grain refinement and solid solution formation highly influenced strength, whereas thermal mismatch and load transfer effects were reduced by debonding.