Miracle-dz/UniFAR-FTUs huggingface dataset:
How we see time – the evolution and current state of visualizations of temporal data

ABSTRACT Time, much like space, has always influenced the human experience due to its ubiquity. Yet, how we have communicated temporal information graphically throughout our history, is still inadequately studied. How does our image of time and temporal events evolve as the human world continuously transforms into a globally more and more synchronized community? Within this overview paper, we elaborate on these questions, we analyze visualizations of time and temporal data from a variety of sources connected to exploratory data analysis. We assign codes and cluster the visualizations based on their graphical properties. The result gives an overview of different visual structures apparent in graphic representations of time.
Estimation of Sugar Content in Wine Grapes via In Situ VNIR–SWIR Point Spectroscopy Using Explainable Artificial Intelligence Techniques

Spectroscopy is a widely used technique that can contribute to food quality assessment in a simple and inexpensive way. Especially in grape production, the visible and near infrared (VNIR) and the short-wave infrared (SWIR) regions are of great interest, and they may be utilized for both fruit monitoring and quality control at all stages of maturity. The aim of this work was the quantitative estimation of the wine grape ripeness, for four different grape varieties, by using a highly accurate contact probe spectrometer that covers the entire VNIR–SWIR spectrum (350–2500 nm). The four varieties under examination were Chardonnay, Malagouzia, Sauvignon-Blanc, and Syrah and all the samples were collected over the 2020 and 2021 harvest and pre-harvest phenological stages (corresponding to stages 81 through 89 of the BBCH scale) from the vineyard of Ktima Gerovassiliou located in Northern Greece. All measurements were performed in situ and a refractometer was used to measure the total soluble solids content (°Brix) of the grapes, providing the ground truth data. After the development of the grape spectra library, four different machine learning algorithms, namely Partial Least Squares regression (PLS), Random Forest regression, Support Vector Regression (SVR), and Convolutional Neural Networks (CNN), coupled with several pre-treatment methods were applied for the prediction of the °Brix content from the VNIR–SWIR hyperspectral data. The performance of the different models was evaluated using a cross-validation strategy with three metrics, namely the coefficient of the determination (R2), the root mean square error (RMSE), and the ratio of performance to interquartile distance (RPIQ). High accuracy was achieved for Malagouzia, Sauvignon-Blanc, and Syrah from the best models developed using the CNN learning algorithm (R2>0.8, RPIQ≥4), while a good fit was attained for the Chardonnay variety from SVR (R2=0.63, RMSE=2.10, RPIQ=2.24), proving that by using a portable spectrometer the in situ estimation of the wine grape maturity could be provided. The proposed methodology could be a valuable tool for wine producers making real-time decisions on harvest time and with a non-destructive way.
Color interpolation algorithm of CCD based on green components and signal correlation

Signal CCD/CMOS sensors capture image information by covering the sensor surface with a color filter array(CFA). For each pixel, only one of three primary colors(red, green and blue) can pass through the color filter array(CFA). The other two missing color components are estimated by the values of the surrounding pixels. In Bayer array, the green components are half of the total pixels, but both red pixel and blue pixel components are quarter, so green components contain more information, which can be reference to color interpolation of red components and blue components. Based on this principle, in this paper, a simple and effective color interpolation algorithm based on green components and signal correlation for Bayer pattern images was proposed. The first step is to interpolate R, G and B components using the method-bilinear interpolation. The second step is to revise the results of bilinear interpolation by adding some green components on the results of bilinear interpolation. The calculation of the values to be added should consider the influence of correlation between the three channels. There are two major contributions in the paper. The first one is to demosaick G component more precisely. The second one is the spectral-spatial correlations between the three color channels is taken into consideration. At last, through MATLAB simulation experiments, experimental pictures and quantitative data for performance evaluation-Peak Signal to Noise Ratio(PSNR) were gotten. The results of simulation experiments show, compared with other color interpolation algorithms, the proposed algorithm performs well in both visual perception and PSNR measurement. And the proposed algorithm does not increase the complexity of calculation but ensures the real-time of system. Theory and experiments show the method is reasonable and has important engineering significance.
Self-Triggered and State-Triggered Sampling Adaptive Fuzzy Design for Full State Constrained Nonlinear Systems

In this article, the problems of state-triggered sampling and self-triggered tracking control for nonlinear systems with constraints are studied. First, the fuzzy observer is designed for the unknown state. In the presence of state-triggered sampling error, the cooperative design of constraint controller is a key problem to be solved. The median value theorem provides help to solve this problem and an asymmetric state-triggering strategy is presented. In addition, it is proved that the closed-loop signals are input-to-state stable, and the sampling error and tracking error are bounded. Then, a general self-triggered tracking control scheme is presented. In order to compare the control performance of different triggering mechanisms, fuzzy observer and logarithmic barrier Lyapunov function are selected also, and the scheme is designed under the framework of backstepping method. Co-designing controllers and scheduling functions is a key issue, so that the physical implementation benefits from not requiring constant monitoring of the state. Finally, the effectiveness of the proposed method is verified by case study, and the control performance of different triggering mechanisms is compared.
Charge injection and polarization fatigue in ferroelectric thin films

Typical experimental data of polarization fatigue in Pb(Zr,Ti)O3 thin films have been presented: (1) The coercive voltage Vc and the shape of the polarization-electric (P‐E) hysteresis loop unnecessarily change with the number N of fatigue cycles except the remanent polarization; (2) the capacitance at voltages close to Vc decreases monotonically with increased N, in comparison with its enhancement at voltages far away from Vc; (3) electrode damage occurs after the appearance of the amount of pinned domain walls; and (4) domain-wall pinning and depinning coexist during fatigue cycling. All phenomena mentioned above are interpreted in terms of charge injection into regions with the inhomogeneities of dielectric constant, conductivity, and polarization, especially near film-electrode interfaces. Pinning and depinning coefficients of domain walls are extracted from fatigue profiles and found to be useful in the prediction of charge injection depending on the fatigue voltage and frequency. Domain-wall motion .
Highly integrated optical 8x8 lambda-router in silicon-on-insulator technology: comparison between the ring and racetrack configuration

In this paper, we demonstrate a compact 8x8 λ-router using multimode-interference (MMI) crossing based on the microring resonator. The 8x8 λ-router was designed and fabricated with a CMOS compatible silicon on insulator technology. MMI is used to reduce the cross talk and the crossing losses of the device. Microrings with a nominal radius of 2.5 μm and small variations of 10 nm of the nominal value allow respectively a free spectral range of 32 nm and spacing between channels of 4 nm. The experimental results are in good agreement with the modeling. The basic add drop filters of the devices exhibit losses of -2 dB and on/off contrast of the resonance of 20 dB. The total losses for one channel are about -4 dB and the imbalance between the 8 channels is lower than 2 dB.
A new perspective on blocking

Abstract It is argued that the essential aspect of atmospheric blocking may be seen in the wave breaking of potential temperature (θ) on a potential vorticity (PV) surface, which may be identified with the tropopause, and the consequent reversal of the usual meridional temperature gradient of θ. A new dynamical blocking index is constructed using a meridional θ difference on a PV surface. Unlike in previous studies, the central blocking latitude about which this difference is constructed is allowed to vary with longitude. At each longitude it is determined by the latitude at which the climatological high-pass transient eddy kinetic energy is a maximum. Based on the blocking index, at each longitude local instantaneous blocking, large-scale blocking, and blocking episodes are defined. For longitudinal sectors, sector blocking and sector blocking episodes are also defined. The 5-yr annual climatologies of the three longitudinally defined blocking event frequencies and the seasonal climatologies of blocking .
High‐order submillimeter mixing in point‐contact and Schottky diodes

The 337‐μm radiation of an HCN laser has been mixed with the radiation of a 3‐mm kylstron in a harmonic mixer employing various types of diodes. Beat notes resulting from different orders of mixing, occurring at frequencies as high as 4.5 THz, could be directly observed on the scope. Gallium arsenide appeared to be the most favorable diode material, whereas the Schottky barrier type produce slightly better results than the conventional GaAs point‐contact diodes. The performance of the heterodyne system at 891 GHz is given in terms of sensitivity (NEP) and conversion loss (Lc).
Development of Consumer-Friendly Surface Electromyography System for Muscle Fatigue Detection

In this study, a low-cost, wireless, and smartphone-controlled surface electromyography (EMG) system was designed and developed for consumers, and the recorded EMG signals were evaluated against a reference laboratory EMG system during fatiguing contraction. Using commercially available inexpensive components, the components of the EMG signal-acquisition circuit were optimized, and a microcontroller was combined with a Bluetooth module. The EMG signals were then converted from analog to digital signals and transmitted to a smartphone via Bluetooth serial communication. EMG signals from the biceps brachii of six healthy subjects were recorded separately using two EMG systems during sustained submaximal isometric contraction until the endurance limit was reached. The root mean square (RMS) and mean power frequency (MPF) of the EMG signals were calculated. The results indicated that both the EMG systems exhibited a characteristic progressive increase in EMGRMS and decrease in EMGMPF during sustained isometric contraction. The relative agreement between the two EMG systems, assessed by intraclass correlation coefficient (ICC), was excellent for EMGRMS (ICC 0.933, P < 0.001) and moderate for EMGMPF (ICC 0.662, P =0.049). The cost of the sensor components in the hardware was ¥ 8,486 per unit. The proposed consumer-friendly EMG system, which is inexpensive and highly versatile in terms of wireless and smartphone accessibility, can detect the phenomenon associated with increased amplitude and low-frequency components during muscle fatigue contraction with a magnitude similar to that of the commercially available laboratory EMG systems.
Factors Influencing the Time of Intubation Using C-MAC D-Blade® Video Laryngoscope: An Observational Cross-Sectional Study

Purpose C-MAC D-Blade® (Karl Storz, Tuttlingen, Germany) video laryngoscope (VL) has proved to be of immense utility in difficult intubation. But unfortunately, in an urgent situation, the predictable correct curvature of the endotracheal tube for effortless intubation is not met. We hypothesized that expertise is the most important variable in intubation and that novice students will be unable to intubate if the angle of curvature is incorrect. Methods An observational cross-sectional study was planned with 30 anesthesia residents, categorized into three groups based on their expertise in laryngoscopy. Students had to intubate an airway mannequin using the C-MAC D-Blade® VL with three different stylet angulations. The curvatures were 80, 100, and 120 degrees, which are commonly encountered in routine day-to-day practice. The time to get a stable glottic view, time to intubate, and ease of intubation were measured. Results The mean time to intubate was the least with 100-degree angulation in group C (19.60 ± 0.97) while the maximum time was in group A with 80-degree angulation (61.49 ± 3.69). A significant difference was noted in time to get a stable glottic view when compared between the groups. There was no difference in time to intubate with different stylet angulations when compared between groups. Conclusions Novices and experts could intubate even if the angle of curvature was incorrect taking more time. The time to laryngoscopy is significantly dependent on experience, but the time to intubate is influenced by the angle of curvature of the stylet.
Mutual information spectra for comparing categorical maps

The continual accumulation of categorical data sets, presented as nominal categories mapped onto regular grids, provides for the increased desire to compare the patterns observed between these maps. We present a measurement scheme for the comparison of categorical maps that decomposes the differences in multidimensional nested coincidence tables according to variables that record occurrence frequencies of categories (Z), at levels of spatial aggregation (Y), on specific maps (X). Sequences of conditional entropies computed according to the specific questions asked (e.g. is there coincidence between colours and locations), characterize the correspondence between the three types of variables in common units (bits) measured by mutual information. The form of these sequences, as a variable runs from coarse to fine detail, referred to as spectra, provide meaningful characterizations of the similarities/differences between categorical maps, including their spatial configuration. We introduce the information theory‐based conceptual framework and illustrate its beneficial application by comparing a series of demonstration maps.
Observers and duality between observation and state feedback for time delay systems

This paper deals with the problem of observer construction for systems with general time-delays in state and output. The spectrum of the infinitesimal generator of the observer semigroup is determined explicitly, and the observer equation is decomposed into a finite- and an infinite-dimensional component. For systems with delays appearing in the state variables only duality results are obtained and the observer is described in the more concrete form of a differential delay equation.
Holographic nanoparticle-polymer composites based on step-growth thiol-ene photopolymerization

We report on the photopolymerization kinetics and volume holographic recording characteristics of silica nanoparticle-polymer composites using thiol-ene monomers capable of step-growth polymerization. Real-time Fourier transform spectroscopy and photocalorimetry are used to characterize the visible light curing kinetics of a thiol-ene monomer system consisting of secondary dithiol with high self-life stability and low odor and triene with rigid structure and high electron density. It is shown that while the nanoparticle-(thiol-ene)polymer composites exhibit high transparency, their saturated refractive index modulation (Δnsat ) and material sensitivity (S) are as large as 1×10−2 and 1615 cm/J, respectively. The polymerization shrinkage is reduced as low as 0.4% as a result of the late gelation in conversion. These values meet the acceptable values for holographic data storage media (i.e., 5×10−3, 500 cm/J and 0.5% for Δnsat, S and shrinkage, respectively). It is also shown that because of the dispersion of inorganic silica nanoparticles and the use of the triene monomer having the rigid structure of the triazine functional group, the thermal stability of recorded holograms is much improved over our previously reported nanoparticle-polymer composites using organic nanoparticles and primary mercaptopropionate trithiol/allyl ether triene monomers [Opt. Lett. 35, 396 (2010)].
An automated pipeline for supervised classification of petal color from citizen science photographs

Abstract Premise Petal color is an ecologically important trait, and uncovering color variation over a geographic range, particularly in species with large distributions and/or short bloom times, requires extensive fieldwork. We have developed an alternative method that segments images from citizen science repositories using Python and k‐means clustering in the hue‐saturation‐value (HSV) color space. Methods Our method uses k‐means clustering to aggregate like‐color pixels in sample images to generate the HSV color space encapsulating the color range of petals. Using the HSV values, our method isolates photographs containing clusters in that range and bins them into a classification scheme based on user‐defined categories. Results We demonstrate the application of this method using two species: one with a continuous range of variation of pink‐purple petals in Geranium maculatum, and one with a binary classification of white versus blue in Linanthus parryae. We demonstrate results that are repeatable and accurate. Discussion This method provides a flexible, robust, and easily adjustable approach for the classification of color images from citizen science repositories. By using color to classify images, this pipeline sidesteps many of the issues encountered using more traditional computer vision applications. This approach provides a tool for making use of large citizen scientist data sets.
NIVEXC: An Electronic Snow-Pole for Real-Time Monitoring of Avalanche Starting Zones

INSIS s.p.a. , La Spezia, Italy ABSTRACT: Knowledge of amount of new snow, total snow depth and internal property of snow-cover in avalanche release zones are well known to be key factors for effective avalanche prediction. However, in case of snow storms and dangerous conditions, manual snow-cover investigations in the upper part of avalanche paths are unfeasible for safety reasons. Nevertheless, monitoring from valley bottom or helicopter by means of traditional snow-poles is often not possible because of bad weather conditions. NIVEXC allows to overcome the mentioned problems, as it is an autonomous electronic snow-pole provided with a vertical array of sensor and suitable for installation in avalanche starting zones. NIVEXC is able to record and real-time transmit to a remote server important snow cover prop-erties, such as total snow height, snow precipitation amounts and rates, temperature profiles. This in-novative device will be described and first results from a full-scale installation during winter season 2012-13 will be presented. KEYWORDS: avalanche forecasting, starting zone monitoring, snow depth measurement, tempera-ture profile. 1 INTRODUCTION Knowledge of snow-cover properties in ava-lanche release areas is of great help for ava-lanche forecasting. However, due to severe conditions typical of starting zones, the devel-opment of instruments for automatic monitoring of snow cover in these zones is a difficult task and only few experiences do exist nowadays. NIVEXC is an electronic snow-pole, for measuring total snow depth, snow precipitation rates and temperature profile in avalanche start-ing zones which has been recently developed with a joint effort of two Italian companies, FLOW-ING & INSIS. Main features of NIVEXC are robustness, reliability, low operating cost, ease of installation and maintenance. NIVEXC technical details are briefly de-scribed at § 2. First full-scale installation and preliminary results are presented at § 3. 2 THE INSTRUMENT NIVEXC pole is made by a cold shaped alu-minium box frame, 3.00 m long and 8 cm wide. The box tube frame has been designed accord-ing to Eurocode#9. Snow cover loads have been estimated on the base of Swiss Guidelines (Margreth, 2007). In order to optimise structural design and to reduce lateral displacements and vibrations, NIVEXC pole has been designed with a full joint at the bottom and provided with a double bracing system placed at 2/5 and 4/5 of its height. Figure 1. A picture of an operational NIVEXC pole; the pole is coloured in black with 10 cm thick yellow stripes applied at 40 cm step in or-der to allow also visual monitoring of snow depth from the valley bottom (see Figure 5). The pole is provided with 14 windows along its length, with a 20 cm gap from one another. Each window is suited to hold a “sensor box” ______________________ * Corresponding author address: Massimiliano Barbolini, FLOW-ING s.r. l. La Spezia, ITALY tel: +39 (0)187 500158; fax: +39 (0)187 529777; email: m.barbolini@flow-ing.com
Adaptive Infrared Image Enhancement by Combining Differential Evolution with Stationary Wavelet Transformation

Considering noise and low contrast of infrared image，an efficient nonlinear adaptive enhancement algorithm，which is based on differential evolution (DE)algorithm and stationary wavelet transform (SWT)，is proposed. Evaluation function is constructed by combing information entropy，signal-noise-ratio with standard deviation of enhanced image. A nonlinear transformation function is designed to enhance the contrast of the infrared image. The optimal transformation parameters are determined by combing DE algorithm with the constructed evaluation function. The proposed algorithm can efficiently enhance the contrast of the infrared image while have a good robust to noise. Experimental results show that the proposed algorithm is better than multi-scale nonlinear enhancement algorithm，stationary wavelet nonlinear enhancement algorithm and histogram equalization algorithm in overall performance.
Meta-analysis of F-test statistics

When conducting a meta-analysis of standardized mean differences (SMDs), it is common to assume equal variances in the two of arms of each study. This leads to Cohen's d SMD estimates for which interpretation is simple. However, this simplicity should not be used as a justification for the assumption of equal variances in situations where evidence may suggest that it is incorrect. Until now, researchers have either used an F-test for each individual study as a justification for the equality of variances or perhaps even conveniently ignored such tools altogether. In this paper we propose using a meta-analysis of F-test statistics for unequal variances prior to the combination of SMD's. This procedure allows some studies to be included that might otherwise be omitted by individual fixed level tests for unequal variances, which could naturally occur even when the assumption of equal variances holds. At the same time, it allows for rejection of the assumption of equal variances for all studies if the cumulative evidence against this assumption is strong. The usefulness of this approach is highlighted via simulation studies and an application to spinal bone mineral density. Four competing variance stabilizing transformations are considered for F-statistics to facilitate the meta-analysis. The variance stabilization results are also applicable to any meta-analysis of F-statistics.