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1. PROGRESSIVE DAMAGE ANALYSIS OF STEEL-REINFORCED CONCRETE BEAMS USING HIGHER-ORDER 1D FINITE ELEMENTS

   https://doi.org/10.1615/IntJMultCompEng.2022045649  

   Nagaraj, Manish H.; Maiaru, M. (January 2023, International Journal for Multiscale Computational Engineering)

   The present work investigates progressive damage in steel-reinforced concrete structures. An elastic-perfectly plastic material response is considered for the reinforcing steel constituent, while the smeared-crack approach is applied to model the nonlinear behavior of concrete. The analysis employs one-dimensional numerical models based on higher-order finite elements derived using the Carrera unified formulation (CUF). A set of numerical assessments is presented to study the mechanical response of a steel-reinforced notched concrete beam loaded in tension. The predictions are found to be in very good agreement with reference experimental observations, thereby validating the numerical approach. It is shown that CUF allows for the explicit representation of the constituents within the composite beam, resulting in accurate solutions in a computationally efficient manner. 

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2. Left Ventricular Geometry, Tissue Composition, and Residual Stress in High Fat Diet Dahl-Salt Sensitive Rats.

   https://doi.org/https://doi.org/10.1007/s11340-020-00664-8  

   Grobbel, M. R.; Lee, L. C.; Watts, S. W.; Fink, G. D.; Roccabianca, S. (January 2021, Experimental mechanics)

   null (Ed.)

   Background Hypertension drives myocardial remodeling, leading to changes in structure, composition and mechanical behavior, including residual stress, which are linked to heart disease progression in a gender-specific manner. Emerging therapies are also targeting constituent-specific pathological features. All previous studies, however, have characterized remodeling in the intact tissue, rather than isolated tissue constituents, and did not include sex as a biological variable. Objective In this study we first identified the contribution of collagen fiber network and myocytes to the myocardial residual stress/strain in Dahl-Salt sensitive rats fed with high fat diet. Then, we quantified the effect of hypertension on the remodeling of the left ventricle (LV), as well as the existence of sex-specific remodeling features. Methods We performed mechanical tests (opening angle, ring-test) and histological analysis on isolated constituents and intact tissue of the LV. Based on the measurements from the tests, we performed a stress analysis to evaluate the residual stress distribution. Statistical analysis was performed to identify the effects of constituent isolation, elevated blood pressure, and sex of the animal on the experimental measurements and modeling results. Results Hypertension leads to reduced residual stress/strain in the intact tissue, isolated collagen fibers, and isolated myocytes in male and female rats. Collagen remains the largest contributor to myocardial residual stress in both normotensive and hypertensive animals. We identified sex-differences in both hypertensive and normotensive animals. Conclusions We observed both constituent- and sex-specific remodeling features in the LV of an animal model of hypertension. 

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3. Overheard: Audio-based Integral Event Inference

   https://doi.org/10.1145/3695771  

   Xu, Honghui; Cai, Zhipeng; Ma, Liran; Li, Yingshu; Seo, Daehee; Li, Wei (September 2024, Journal of Data and Information Quality)

   There is no doubt that the popularity of smart devices and the development of deep learning models bring individuals too much convenience. However, some rancorous attackers can also implement unexpected privacy inferences on sensed data from smart devices via advanced deep-learning tools. Nonetheless, up to now, no work has investigated the possibility of riskier overheard, referring to inferring an integral event about humans by analyzing polyphonic audios. To this end, we propose an Audio-based integraL evenT infERence (ALTER) model and two upgraded models (ALTER-p and ALTER-pp) to achieve the integral event inference. Specifically, ALTER applies a link-like multi-label inference scheme to consider the short-term co-occurrence dependency among multiple labels for the event inference. Moreover, ALTER-p uses a newly designed attention mechanism, which fully exploits audio information and the importance of all data points, to mitigate information loss in audio data feature learning for the event inference performance improvement. Furthermore, ALTER-pp takes into account the long-term co-occurrence dependency among labels to infer an event with more diverse elements, where another devised attention mechanism is utilized to conduct a graph-like multi-label inference. Finally, extensive real-data experiments demonstrate that our models are effective in integral event inference and also outperform the state-of-the-art models. 

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4. Bayesian semi-supervised inference via a debiased modeling approach

   https://doi.org/10.1016/j.ecosta.2025.05.001  

   Sert, Gözde; Chakrabortty, Abhishek; Bhattacharya, Anirban (May 2025, Econometrics and Statistics)

   Inference in semi-supervised (SS) settings has gained substantial attention in recent years due to increased relevance in modern big-data problems. In a typical SS setting, there is a much larger-sized unlabeled data, containing only observations of predictors, and a moderately sized labeled data containing observations for both an outcome and the set of predictors. Such data naturally arises when the outcome, unlike the predictors, is costly or difficult to obtain. One of the primary statistical objectives in SS settings is to explore whether parameter estimation can be improved by exploiting the unlabeled data. We propose a novel Bayesian method for estimating the population mean in SS settings. The approach yields estimators that are both efficient and optimal for estimation and inference. The method itself has several interesting artifacts. The central idea behind the method is to model certain summary statistics of the data in a targeted manner, rather than the entire raw data itself, along with a novel Bayesian notion of debiasing. Specifying appropriate summary statistics crucially relies on a debiased representation of the population mean that incorporates unlabeled data through a flexible nuisance function while also learning its estimation bias. Combined with careful usage of sample splitting, this debiasing approach mitigates the effect of bias due to slow rates or misspecification of the nuisance parameter from the posterior of the final parameter of interest, ensuring its robustness and efficiency. Concrete theoretical results, via Bernstein--von Mises theorems, are established, validating all claims, and are further supported through extensive numerical studies. To our knowledge, this is possibly the first work on Bayesian inference in SS settings, and its central ideas also apply more broadly to other Bayesian semi-parametric inference problems. 

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5. Input- Reflectionless Acoustic-Wave-Lumped- Element Resonator-Based Bandpass Filters

   Psychogiou, Dimitra; Simpson, Dakotah; Gómez-García, Roberto (August 2018, 2018 IEEE/MTT-S International Microwave Symposium - IMS)

   This paper reports on an RF design methodology for acoustic-wave-resonator-(AWR)-based bandpass filters (BPFs) with input-reflectionless behavior in both their passband and stopband regions. The proposed concept is based on acoustic-wave-lumped-element resonators (AWLRs) that are incorporated in series-cascaded reflectionless stages (RLSs). Each RLS comprises a first-order bandpass section-shaped by three impedance inverters and one AWLR-and a first-order resistively-terminated bandstop section-shaped by two impedance inverters and one AWLR-that are designed to exhibit complementary transfer functions. In this manner, an input-reflectionless behavior can be obtained both at the passband and stopband regions of the filter. In addition, the use of AWLRs in the RLSs facilitates the realization of high-quality-factor quasi-elliptic-type transfer functions with fractional bandwidths (FBWs) that are wider than the electromechanical coupling coefficient (kt 2 ) of its constituent AWRs. For proof-of-concept validation purposes, one- and two-state prototypes were manufactured, and measured at 418 MHz using commercially-available surface-acoustic-wave resonators. 

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