Miracle-dz/UniFAR-FTUs huggingface dataset:
Removing the Ambiguity in Lamb Wave-Based Damage Localization

The aim of this work is the investigation and improvement of a Structural Health Monitoring method based on Lamb waves propagation. This research concentrates on ambiguity in damage localization using attached piezoelectric transducers as sources and sensors of the elastic waves. A linear phased array is chosen as a starting point of the investigation. It has a great advantage in damage localization, namely it enables to amplify the wave reflected from damage, increasing the signal to noise ratio, and precisely indicates not only the distance to damage from the array but also the direction on which the damage lies. However it has also a great disadvantage which needs to be handled – the localization results are symmetric in relation to the line on which the transducers of linear phased array are placed. This obviously does not facilitate Structural Health Monitoring process and precise indication of damage placement. Therefore this investigation aims to improve this localization method by removing the ambiguity in results. In this work the placement of transducers forming a linear phased array is modified to achieve this goal. Several array modification are investigated and compared in order to determine the best solution. Presented research is based on theoretical calculations as well as laboratory experiments on prepared specimens. The measurements are conducted with a compact 13–channel SHM system controlled by a MATLAB® script.
MODELING THE THERMAL DYNAMICS OF A SINGLE ROOM IN COMMERCIAL BUILDINGS AND FAULT DETECTION

of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science MODELING THE THERMAL DYNAMICS OF A SINGLE ROOM IN COMMERCIAL BUILDINGS AND FAULT DETECTION By Yashen Lin August 2012 Chair: Prabir Barooah Major: Mechanical Engineering Modern control strategy in building automation control has large potential of saving energy. This thesis attempts to develop a model which describes the thermal dynamics of a single room that can be used for intelligent control, such as model predictive control. The use of the model in fault detection is discussed in the second part of this thesis. In the first part, three important questions in the modeling problem are discussed: (1) How accurate should the model be to be useful for modern control methods? (2) What model structure should be used so that the desired accuracy can be achieved and yet it is not too complicated? (3) How should we determine the parameters in the model once the model structure is chosen? Various model structures are compared, and a second order model using electrical analogy is found to be a good choice. Experimental data from Pugh Hall on University of Florida are collected for model calibration and validation. It is found that the data is crucial. Normal closed loop operation data may lead to grossly wrong parameter estimation, even with rich excitation. The effect of open door on the model is also discussed, and a modified model is developed. In the second part, the fault caused by occupants is studied. Unknown input observer method (UIO), a model based method, is implemented for fault detection. Using the model we got from the first part, we successfully detected the open door with UIO. However, implementation in another model structure shows that the technique has certain limitation. A tradeoff is found in such situation.
Podnoszenie przedsiebiorczosci wsrod studentow poprzez zespolowe prace projektowe (Increasing entrepreneurship among students through collaborative project work)

Creating entrepreneurial attitudes among students can also use for non-directional courses, and the condition of this is an appropriate method of teaching. A commonly known method of teaching the exercises, which includes: case studies, simulation game, brainstorming, or not liked by the students – polling, may be subject to modification. On their basis, we can create new and original teaching methods. The article will present its own method of conducting exercises with the course of design management systems, which is based on project method and has worked out for ten years. This method can also be used successfully in other courses
A novel integrated acoustic gas and temperature sensor

Acoustic temperature sensors have the advantages of a high-resolution frequency output and ease of integration with other acoustic sensors but require hermetic packaging to prevent sensor contamination. Surface-skimming bulk-wave (SSBW) devices have been found to be much less sensitive to surface contamination than other acoustic devices, and although their temperature response has been studied extensively, they have not been studied specifically as temperature sensors. Surface acoustic wave (SAW) based chemical sensors requiring temperature measurement or control are susceptible to temperature measurement error because the temperature cannot be measured in the same location as the chemical sensor. The objectives of this work were to examine the temperature characteristics and performance of a SSBW temperature sensor when integrated with a SAW condensation and humidity sensor in a novel design. The SSBW temperature sensor had over an order of magnitude less sensitivity to condensation and water uptake in certain polyimide films than an integrated SAW gas sensor indicating that this design is practical for sensing films in the delay path where film thickness is carefully considered.
The use of a simulation, a hybrid Taguchi, and dual response surface methods in the automated material handling system tool-to-tool strategy for a 300-mm fab

With the increase in the size and weight of 300-mm wafers, manual handling has become difficult and automated material handling systems (AMHS) are necessary. The 300-mm fab requires only one type of vehicle and rail to connect all of the process resources, allowing vehicles to travel directly between intrabay and interbay systems. This type of transportation is a direct tool-to-tool transportation strategy. This paper aims to analyse the impact of direct tool-to-tool transportation. The present study used a discrete-event simulation to create a 300-mm semiconductor manufacturing flow and executed a factorial experiment of three factors based on uniform design, including the direct ratio, the stocker capacity and the number of machine load ports. Finally, using the dual-response surface method, the most important of the three factors and the best performance were determined. The results show promise for the proposed tool-to-tool transportation strategy in solving a practical application. [Received: 9 February 2010; Revised: 6 October 2010; Accepted: 17 November 2010]
A SIMULATION MODEL FOR TIMBER DRYING CHECKED BY MEASUREMENTS AT TECHNICAL KILNS

ABSTRACT A physically based simulation program for timber drying, which predicts the integral drying course, the profiles of moisture content, and internal stress during drying, was checked by data from technical drying runs. A data logging system served to record the data sets from several drying runs at diverse kilns. The comparison of model predictions and measured data led to the following conclusions: The integral drying course, i.e. time dependence of the average moisture content, can be well precalculated in quantity. Calculations of the moisture profiles were found to be right in tendency, but not in accuracy. Stress calculation by means of a visco-elastic Burger model leads to results correct in tendency, but to high in comparison with measured data. To improve the stress calculation mechano-sorptive creep by models of Salin and Ranta-Maunus were tested. The calculation of these models corresponded with measurements from laboratory experiments. The simulation program is estimated to be applicable.
A New Constant Extinction Angle Control for AC/DC/AC Static Convertors

Maximum utilization of an invertor's capacity and minimum consumption of reactive power demands an accurate constant extinction angle control. A new scheme for such a control is presented that is based on the integration of each commutating voltage waveform from -s+ ? c, thereby obtaining a simulation of the steady- state commutation equation. The resulting control is capable of fresh computation of the firing angle every cycle. The control is extended to cover the convertor operation over its full range from a minimum permissible angle of delay to the minimum permissible extinction angle.
Nonlinear aircraft tracking filter utilizing a point mass flight dynamics model

A nonlinear aircraft tracking filter using a point mass flight dynamics model with three degrees of freedom is presented. While the models used by conventional air traffic control tracking filters are based on simple kinematics, the model for the present filter is based not only on kinematic relations but also on three-dimensional aircraft translational force equations and control variables. This allows for practical and sophisticated implementation of the attitude effects on translational acceleration. The control variables, which consist of the angle of attack, roll angle, and thrust setting, are treated as states with random processes. Tracking with simulation data indicates that the present filter is superior to other single and multiple model-based filters in terms of position and course accuracy, and the model associated with it is insensitive to flight motion types and design parameters. The results of tracking with real flight data also correspond well with those found by tracking with the simulation data.
Determination of damper winding and rotor iron currents in convertor- and line-fed synchronous machines

The damper winding currents of a synchronous machine with a solid iron rotor are analyzed. Based on the self and mutual inductance modelling technique, the damper currents are described by a detailed damper model taking the damper cage and the rotor iron into account. The model's component elements are determined by the finite element method. Theoretical results are verified by measuring damper bar currents of a six-phase synchronous machine fed by two six-pulse converters. For a number of different operating modes the model is used to calculate the damper current distribution of a six-phase machine. >
Polarization fluctuation measurements on installed single-mode optical fiber cables

Measurements are reported of the polarization fluctuation observed at 1550 nm on samples of cable that Telecom Australia has installed in its interexchange network. The rate of polarization fluctuations is found to be slow, on the order of hours. The fluctuation in the polarization angle is typically in the range of 2-10 degrees each day, with some changes up to about 25 degrees . The results indicate there are no significant limitations on implementing polarization control in a coherent system receiver. >
Impact and Variability of Meteorological Parameters on Rice Crop at Siddharthnagar, Uttar Pradesh, India

The present study explores the impacts and variability of meteorological parameter on the rice yields at Siddharthnagar of Uttar Pradesh, India. This study that the maximum and minimum temperatures during the period 2011 to 2020 show increasing trends. Whereas the duration of sunlight increased in June and July. Whereas the rainfall data shows decreasing trends for the period August-September. Furthermore, this study suggests that there was a decrease in rainfall trends during the paddy growing period. A negative correlation was observed with rainfall, particularly during the duff stage, indicating that wetting during the flowering to maturity period may be decisive. This study suggests taking into account the variability of annual or seasonal temperatures and precipitation within the region. The warming trend and irregular precipitation over time may have a significant impact on paddy farming. As a result, plans must be developed to manage the impact of the current variability of meteorological parameters on the paddy yields in this district of Uttar Pradesh by developing appropriate alternatives for increasing paddy crop production.
Fast Analytical Short-Circuit Current Calculation of Rectifier Fed Auxiliary Subsystems

The course of time of a three-phase rectifier system which its alternating valve participation can be interpreted as a continuous sequence of alternating switching states. To allow a more convenient calculation, the substitutional circuit with the converter is transformed into state-space coordinates. Hereby each operational mode of the rectifier can be represented by two linear independent space-phasor component networks. In the state-space, an analytical solution for this boundary value system can be carried out. After a retransformation back into the time domain, its time functions can be derived. In contrast to other calculation methods, no assumptions or simplifications have to be made like ideal smooth DC currents. Furthermore, all states of operation of the rectifier bridge can be easily calculated, which cover DC side idle-running to DC short-circuit.
Waveform Design for Energy Efficient OFDM Transmission

In this chapter, a green radio transmission using the binary phase-shift keying (BPSK) modulated orthogonal frequency-division multiplexing (OFDM) signal is addressed. First, the OFDM transmission signal is clearly stated. For a specified performance of the system, the least transmit power occurs by the optimal OFDM shape, which is designed to minimize the average inter-carrier interference power taking into account the characteristic of the transmit antenna and the detection process at the receiver. The optimal waveform is obtained by applying the calculus of variations, which leads to a set of differential equations (known as Euler equations) with constraint and boundary conditions. Results show the transmission effectiveness of the proposed technique in the shaping of the signal, as well as its potential to be further applied to smart context-aware green wireless communications.
Effects of different sedatives/analgesics on stress responses in patients undergoing craniotomy and bone flap decompression

Objective To explore the effects of sedation and analgesia with dexmedetomidine and other drugs on the stress response in patients with cerebral hemorrhage after craniotomy hematoma removal and bone flap decompression and insertion of an indwelling endotracheal catheter. Methods A total of 180 patients with cerebral hemorrhage with consciousness disturbance who underwent emergency surgery were included in this study. They were divided into six groups treated with propofol, dexmedetomidine, lidocaine, sufentanil, dezocine, and remifentanil, respectively. Intravenous medication was given after recovery of spontaneous respiration, and stress responses were compared among the group. Results Serum concentrations of norepinephrine, epinephrine, and cortisol and systolic blood pressure were significantly correlated with drug treatment. Serum norepinephrine concentrations differed significantly among the groups, except between the sufentanil and propofol groups. There were significant differences in serum epinephrine concentrations among all groups, and significant differences in serum cortisol concentrations among all groups, except the propofol, dexmedetomidine, and lidocaine groups. Conclusion Dexmedetomidine can reduce the stress response in patients with intracerebral hemorrhage undergoing emergency craniotomy and bone flap decompression, and can reduce adverse events from an indwelling endotracheal catheter 3 hours post-operation.
Endurance Enhancement and High Speed Set/Reset of 50 nm Generation HfO2 Based Resistive Random Access Memory Cell by Intelligent Set/Reset Pulse Shape Optimization and Verify Scheme

This paper proposes a verify-programming method for the resistive random access memory (ReRAM) cell which achieves a 50-times higher endurance and a fast set and reset compared with the conventional method. The proposed verify-programming method uses the incremental pulse width with turnback (IPWWT) for the reset and the incremental voltage with turnback (IVWT) for the set. With the combination of IPWWT reset and IVWT set, the endurance-cycle increases from 48 ×103 to 2444 ×103 cycles. Furthermore, the measured data retention-time after 20 ×103 set/reset cycles is estimated to be 10 years. Additionally, the filamentary based physical model is proposed to explain the set/reset failure mechanism with various set/reset pulse shapes. The reset pulse width and set voltage correspond to the width and length of the conductive-filament, respectively. Consequently, since the proposed IPWWT and IVWT recover set and reset failures of ReRAM cells, the endurance-cycles are improved.
EXPERIMENTAL STUDY OF A VENTILATED SUPERCAVITATING VEHICLE

Supercavitating vehicles need to be supplied with an artificial cavity through ventilation until they accelerate to conditions at which a natural supercavity can be sustained. A study has been carried out in the high-speed water tunnel at St. Anthony Falls Laboratory to investigate some aspects of the flow physics of such a supercavitating vehicle. Digital strobe photography images were taken to qualitatively describe the cavity shape and wake details. In addition, the amount of ventilation gas required to sustain an artificial cavity at different velocities was investigated. It was found that the strut shape critically affects air demand through cavity-strut wake interaction. The wake of ventilated cavities was then characterized quantitatively using Particle Image Velocimetry (PIV). Since two-camera, filtered PIV was prohibitively costly due to the large amount of fluorescent particles required to seed the tunnel, a new grayscale technique was developed to measure the void fraction of gas to liquid in the wake of the supercavitating body. Further PIV measurements are currently underway to explore this grayscale technique in bubbly wakes.
Molecular and clinical signatures in Acute Kidney Injury define distinct subphenotypes that associate with death, kidney, and cardiovascular events

Introduction: AKI is a heterogeneous syndrome defined via serum creatinine and urine output criteria. However, these markers are insufficient to capture the biological complexity of AKI and not necessarily inform on future risk of kidney and clinical events. Methods: Data from ASSESS-AKI was obtained and analyzed to uncover different clinical and biological signatures within AKI. We utilized a set of unsupervised machine learning algorithms incorporating a comprehensive panel of systemic and organ-specific biomarkers of inflammation, injury, and repair/health integrated into electronic data. Furthermore, the association of these novel biomarker-enriched subphenotypes with kidney and cardiovascular events and death was determined. Clinical and biomarker concentration differences among subphenotypes were evaluated via classic statistics. Kaplan-Meier and cumulative incidence curves were obtained to evaluate longitudinal outcomes. Results: Among 1538 patients from ASSESS-AKI, we included 748 AKI patients in the analysis. The median follow-up time was 4.8 years. We discovered 4 subphenotypes via unsupervised learning. Patients with AKI subphenotype 1 (injury cluster) were older (mean age +/- SD): 71.2 +/- 9.4 (p<0.001), with high ICU admission rates (93.9%, p<0.001) and highly prevalent cardiovascular disease (71.8%, p<0.001). They were characterized by the highest levels of KIM-1, troponin T, and ST2 compared to other clusters (P<0.001). AKI subphenotype 2 (benign cluster) is comprised of relatively young individuals with the lowest prevalence of comorbidities and highest levels of systemic anti-inflammatory makers (IL-13). AKI Subphenotype 3 (chronic inflammation and low injury) comprised patients with markedly high pro-BNP, TNFR1, and TNFR2 concentrations while presenting low concentrations of KIM-1 and NGAL. Patients with AKI subphenotype 4 (inflammation-injury) were predominantly critically ill individuals with the highest prevalence of sepsis and stage 3 AKI. They had the highest systemic (IL-1B, CRP, IL-8) and kidney inflammatory biomarker activity (YKL-40, MCP-1) as well as high kidney injury levels (NGAL, KIM-1). AKI subphenotype 3 and 4 were independently associated with a higher risk of death compared to subphenotype 2. Moreover, subphenotype 3 was independently associated with CKD outcomes and CVD events. Conclusion: We discovered four clinically meaningful AKI subphenotypes with statistical differences in biomarker composites that associate with longitudinal risks of adverse clinical events. Our approach is a novel look at the potential mechanisms underlying AKI and the putative role of biomarkers investigation.
Coronary stent fracture in an octogenarian patient: from bad to worse

1. Department of Cardiology, Asklepeion General Hospital, Athens, Greece; 2. Department of Critical Care Medicine, Asklepeion General Hospital, Athens, Greece; 3. 6 Department of Orthopedics, Asklepeion General Hospital, Athens, Greece; 4. Department of Neurology, Democritus University of Thrace, Alexandroupolis, Greece; 5. Department of Psychiatry, Attikon University Hospital, Athens, Greece ✉ Correspondence to: andtridoc@yahoo.gr https://doi.org/10.11909/j.issn. 1671-5411.2021. 11.009
SOME ASYMPTOTIC ESTIMATES OF BERGMAN KERNEL

In this paper, we give a uniform L asymptotic expansion of Bergman kernel on the collection of n-dimensional polarized Kähler manifolds (M,ω, L, h) with Ricci lower bound −Λ and non-collapsing condition Vol (B1(x)) ≥ v > 0. Under the additional lower bound on bisectional curvature, we will also give a uniform C asymptotic estimate of Bergman kernel for all sufficiently large m, which improves a theorem of Jiang [20]. By calculating the Bergman kernels on orbifolds, we disprove the analogy of a conjecture of Donaldson-Sun [13] when the assumption of an upper bound for the Ricci curvature is removed.
Revealing the Field Sub-subgiant Population Using a Catalog of Active Giant Stars and Gaia EDR3

Sub-subgiant stars (SSGs) fall below the subgiant branch and/or red of the giant branch in open and globular clusters, an area of the color–magnitude diagram (CMD) not populated by standard stellar evolution tracks. One hypothesis is that SSGs result from rapid rotation in subgiants or giants due to tidal synchronization in a close binary. The strong magnetic fields generated inhibit convection, which in turn produces large starspots, radius inflation, and lower-than-expected average surface temperatures and luminosities. Here we cross-reference a catalog of active giant binaries (RS CVns) in the field with Gaia EDR3. Using the Gaia photometry and parallaxes, we precisely position the RS CVns in a CMD. We identify stars that fall below a 14 Gyr, metal-rich isochrone as candidate field SSGs. Out of a sample of 1723 RS CVn, we find 448 SSG candidates, a dramatic expansion from the 65 SSGs previously known. Most SSGs have rotation periods of 2–20 days, with the highest SSG fraction found among RS CVn with the shortest periods. The ubiquity of SSGs among this population indicates that SSGs are a normal phase in evolution for RS CVn-type systems, not rare by-products of dynamical encounters found only in dense star clusters as some have suggested. We present our catalog of 1723 active giants, including Gaia photometry and astrometry, and rotation periods from the Transiting Exoplanet Survey Satellite and International Variable Star Index (VSX). This catalog can serve as an important sample to study the impacts of magnetic fields in evolved stars.