Miracle-dz/UniFAR-FTUs huggingface dataset:
Stochastic optimization of controlled partially observable Markov decision processes

We introduce an online algorithm for finding local maxima of the average reward in a partially observable Markov decision process (POMDP) controlled by a parameterized policy. Optimization is over the parameters of the policy. The algorithm's chief advantages are that it requires only a single sample path of the POMDP, it uses only one free parameter /spl beta//spl isin/(0, 1), which has a natural interpretation in terms of a bias-variance trade-off, and it requires no knowledge of the underlying state. In addition, the algorithm can be applied to infinite state, control and observation spaces. We prove almost-sure convergence of our algorithm, and show how the correct setting of /spl beta/ is related to the mixing time of the Markov chain induced by the POMDP.
A 38.5-fJ 14.4-ns Robust and Efficient Subthreshold-to-Suprathreshold Voltage-Level Shifter Comprising Logic Mismatch-Activated Current Control Circuit

This brief presents a robust and energy-efficient voltage level shifter (VLS) for wide-range conversion from the subthreshold to the suprathreshold regime. The proposed VLS contains a new logic mismatch detection circuit to address the exist contention current of the conversion stage. A power reducer circuit is introduced to increase the drivability of pull-up and pull-down devices in linear and cut-off regions and further energy-consuming improvement. The proposed VLS is simulated using a 0.18-<inline-formula> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> process, the minimal convertible voltage is 0.2 V (deep subthreshold region) for the input signal. Post-layout simulation considering process voltage temperature (PVT) variations proves the proposed VLS outperforms previous designs in several aspects. The results report the consuming energy of 38.5 fJ per transition, a static power of 73.4 pW, and a delay of 14.4 ns when converting range is 0.4 V to 1.8 V. The proposed VLS occupies a 59.98-<inline-formula> <tex-math notation="LaTeX">$\mu \text{m} ^{\mathrm{ 2}}$ </tex-math></inline-formula> silicon area.
Exploration of Shock-Droplet Ignition and Combustion

Liquid fuels are desirable in aerospace applications due to their higher energy density when compared to gaseous fuels. With the advent of detonation-based engines, it is necessary to characterize and analyze how liquid fuel interacts with detonation waves as well as shocks to ignite. While liquid fuel sprays have been proven to successfully aid and sustain detonations, the physical mechanism by which the individual liquid droplets accomplish this is yet to be understood. Such knowledge allows for more predictable detonation properties, which in turn can let detonation-based engines be sustained more easily. This research seeks to quantify and characterize interactions of liquid fuels with detonations and shocks, analyzing the breakup mechanism as well as the ignition of select fuels. Such effects will be characterized for several different mixture compositions as well as shock and detonation speeds. Primary analysis techniques include shadowgraph, Schlieren, and chemiluminescence imaging. Data on pressure will also be taken with pressure transducers to confirm shock and detonation properties. This research will further the progress of liquid fuel detonation-based engines by enabling more predictable and sustainable detonations.
Numerical simulation of superconducting accelerator magnets

Modeling and simulation are key elements in assuring the fast and successful design of superconducting magnets. After a general introduction the paper focuses on electromagnetic field computations, which are an indispensable tool in the design process. A technique which is especially well suited for the accurate computation of magnetic fields in superconducting magnets is presented. This method couples boundary elements (BEM) which discretize the surface of the iron yoke and finite elements (FEM) for the modeling of the non linear interior of the yoke. The formulation is based on a total magnetic scalar potential throughout the whole problem domain. The results for a short dipole model are presented and compared to previous results, which have been obtained from a similar BEM-FEM coupled. vector potential formulation.
Collisional excitation of H2 molecules by H atoms

Three-dimensional quasi-classical trajectories on an accurate potential energy surface have been used to determine converged state-to-state rate constants for transitions among the low-energy (v, j) states of molecular hydrogen as the result of collisions with atomic hydrogen in a warm gas. Where available, fully converged three-dimensional quantum cross sections have been incorporated into the evaluation of the rate constants. The temperature dependence of the rate constants has been parameterized over the temperature range 600-10,000 K. Critical densities and rates for ortho/para interconversion for the low-energy states are given at representative temperatures. Our results are compared with previous evaluations of rate constants for H+H 2 . Reactive and nonreactive transitions are considered separately, and the relative importance of various types of transition is discussed
Thunderstorms above Frontal Surfaces in Environments without Positive CAPE. Part I: A Climatology

Abstract The first of two papers describing thunderstorms that occur above frontal surfaces, frequently in environments without positive convective available potential energy (CAPE), focuses on the climatology of such storms for the conterminous United States. The dataset used consists of 1093 observations made over a 4-year period. The events were selected using conventional network data and a set of criteria that eliminated thunderstorms rooted in the boundary layer. A composite of the dataset shows that the typical “elevated” thunderstorm occurs northeast of an associated surface low-pressure center, and north of a surface warm front in a region with northeasterly surface winds. The planetary boundary layer is generally very stable as determined by comparisons with both the 50-kPa and 85-kPa air. The thunderstorms are usually found in the left exit region of a low-level wind maximum (an area of horizontal deformation). The large-scale environment is strongly baroclinic with large vertical wind shear an.
NONLINEAR GENERALIZED BEAM THEORY FOR COLD-FORMED STEEL MEMBERS

A geometrically nonlinear Generalized Beam Theory (GBT) is formulated and its application leads to a system of equilibrium equations which are valid in the large deformation range but still retain and take advantage of the unique GBT mode decomposition feature. The proposed GBT formulation, for the elastic post-buckling analysis of isotropic thin-walled members, is able to handle various types of loading and arbitrary initial geometrical imperfections and, in particular, it can be used to perform "exact" or "approximate" (i.e., including only a few deformation modes) analyses. Concerning the solution of the system of GBT nonlinear equilibrium equations, the finite element method (FEM) constitutes the most efficient and versatile numerical technique and, thus, a beam FE is specifically developed for this purpose. The FEM implementation of the GBT post-buckling formulation is reported in some detail and then employed to obtain numerical results, which validate and illustrate the application and capabilities of the theory.
Evidence of outward flow of plasma in a coronal hole

The solar spectrum was photographed in the range 200--700 A with a grazing-incidence, stigmatic, rocket spectrograph. Doppler shifts of the three coronal lines Si XI (303 A), Mg X (610 A) and Mg IX (368 A) were measured for various regions of the solar disk including a coronal hole. From the relative shifts in the latter region an average outward velocity of 16 km s/sup -1/ was computed for the plasma in the coronal hole. The full widths at half-maximum for the above lines were appreciably less in the coronal hole region than in a quiet region, indicating a lower temperature in the hole. Both the measured velocity and the temperature results are consistent with solar wind data and with current theories of coronal holes. (AIP)
Design of low-power, low-voltage, differential I/O links for High Energy Physics applications

This work presents the design of a low-power, differential signaling, input/output data link in a 65 nm CMOS process for high energy physics (HEP) experiments. The proposed driver, able to operate at 320 Mbps or 640 Mbps with a normalized power dissipation of 3.125 mW/Gbps, is meant to drive short distance (between 2 and 10 cm) transmission lines located to the module hybrid circuit. A de-emphasis technique has been adopted to reduce the impedance mismatch effects between the driver output and the transmission line. This paper will discuss in detail the solutions implemented in the design and will describe the simulation results.
Selection of projection set and the order of calculation in ordered subsets expectation maximization method

In ordered subsets expectation maximization (OS-EM) the projection data are grouped into subsets and a pixel in a reconstructed image is updated by using projections in each subset. The aim of the study is to analyze the relationship between the quality of images and the selection of subsets or the access order of calculation among the subsets. The image quality was assessed with the mean square error, chi-square error and newly proposed error measures defined in the frequency domain. The results showed the recovery speed of the low to middle frequency components of an image is increased by the access order in calculation, in which the total number of subsets is divided by two or three, and subsets are accessed with the order separating neighboring subsets as much as possible.
Message Framing Pada Green Advertisement Terhadap Purchase Intention

Kesadaran dari konsumen dalam pentingnya menjaga lingkungan mempengaruhi konsumen dalam membeli produk dengan beralih ke produk ramah lingkungan. Salah satu upaya untuk menjaga purchase intention pada masyarakat diberikan sebuah message framing dalam melakukan pengiklanan. Terdapat dua strategi message framing yaitu framing positif dan framing negatif. Maka dari itu, penelitian ini bertujuan untuk mengetahui adanya pengaruh message framing terhadap purchase intention dengan mengetahui ada tidaknya perbedaan purchase intention pada subjek yang diberi message framing positif dan pada subjek yang diberi message framing negatif. Metode Penelitian adalah kuantitatif eksperimen dengan menggunakan teknik non random sampling dengan convenience sampling. Subjek berusia 18-24 tahun sebanyak 40 mahasiswa Universitas Negeri Semarang. Subjek dibagi menjadi 2 kelompok dengan masing-masing sebanyak 20 mahasiswa. Pada satu kelompok diberikan perlakuan message framing positif sedangkan kelompok lain message framing negatif. Metode analisis dilakukan dengan menggunakan uji independent t test dan menunjukkan hasil nilai signifikansi sebesar 0.797. Hasil analisis yang didapatkan menunjukkan bahwa hipotesis penelitian ditolak sehingga hal ini dapat disimpulkan bahwa tidak ada pengaruh message framing pada green advertisement terhadap purchase intention meskipun didapatkan sedikit perbedaan mean antara kelompok message framing positif dan kelompok message framing negatif. Selain itu gambaran umum purchase intention pada kelompok message framing positif berada pada kategori sedang, sementara pada kelompok message framing negatif berada pada kategori tinggi.
Genome-Wide Analysis of ATP Binding Cassette (ABC) Transporters in Peach (Prunus persica) and Identification of a Gene PpABCC1 Involved in Anthocyanin Accumulation

The ATP-binding cassette (ABC) transporter family is a large and diverse protein superfamily that plays various roles in plant growth and development. Although the ABC transporters are known to aid in the transport of a wide range of substrates across biological membranes, their role in anthocyanin transport remains elusive. In this study, we identified a total of 132 putative ABC genes in the peach genome, and they were phylogenetically classified into eight subfamilies. Variations in spatial and temporal gene expression levels resulted in differential expression patterns of PpABC family members in various tissues of peach. PpABCC1 was identified as the most likely candidate gene essential for anthocyanin accumulation in peach. Transient overexpression of PpABCC1 caused a significant increase in anthocyanin accumulation in tobacco leaves and peach fruit, whereas virus-induced gene silencing of PpABCC1 in the blood-fleshed peach resulted in a significant decrease in anthocyanin accumulation. The PpABCC1 promoter contained an MYB binding cis-element, and it could be activated by anthocyanin-activator PpMYB10.1 based on yeast one-hybrid and dual luciferase assays. Thus, it seems that PpABCC1 plays a crucial role in anthocyanin accumulation in peach. Our results provide a new insight into the vacuolar transport of anthocyanins in peach.
Lipoprotein(a) in Atherosclerotic Diseases: From Pathophysiology to Diagnosis and Treatment

Lipoprotein(a) (Lp(a)) is a low-density lipoprotein (LDL) cholesterol-like particle bound to apolipoprotein(a). Increased Lp(a) levels are an independent, heritable causal risk factor for atherosclerotic cardiovascular disease (ASCVD) as they are largely determined by variations in the Lp(a) gene (LPA) locus encoding apo(a). Lp(a) is the preferential lipoprotein carrier for oxidized phospholipids (OxPL), and its role adversely affects vascular inflammation, atherosclerotic lesions, endothelial function and thrombogenicity, which pathophysiologically leads to cardiovascular (CV) events. Despite this crucial role of Lp(a), its measurement lacks a globally unified method, and, between different laboratories, results need standardization. Standard antilipidemic therapies, such as statins, fibrates and ezetimibe, have a mediocre effect on Lp(a) levels, although it is not yet clear whether such treatments can affect CV events and prognosis. This narrative review aims to summarize knowledge regarding the mechanisms mediating the effect of Lp(a) on inflammation, atherosclerosis and thrombosis and discuss current diagnostic and therapeutic potentials.
An algorithm to simulate surface creation without element deletion or remeshing

One of the major obstacles to modelling discrete fracture and fragmentation of materials within the finite element (FE) framework is the inability to easily model the resulting geometry changes. This paper presents an algorithm for three‐dimensional element cohesion and separation implemented in the explicit FE code DYNA3D. The algorithm handles mesh definition and solution difficulties necessary for general element separation with minimal additional effort required of the user.
Arctic Sea Ice Lead Detection from Chinese HY-2B Radar Altimeter Data

Sea ice thickness is one of the essential characteristics of sea ice. Sea ice lead detection is the key to sea ice thickness estimation from radar altimetry data. This research studies ten different surface type classification methods, including supervised learning, unsupervised learning, and threshold methods, being applied to the HY-2B radar altimeter data collected in October 2019 in the Arctic Ocean. The Sentinel-1 Synthetic Aperture Radar (SAR) images were used for training and validation of the classifiers. Compared with other classifiers, the supervised Bagging ensemble learning classifier showed excellent and robust performance with overall accuracy up to 95.69%. In order to assess the performance of the Bagging classifier in practical applications, lead fractions from January 2019 to March 2021 based on the HY-2B radar altimeter data were mapped using the trained Bagging classifier and compared to the CryoSat-2 L2I data product. The results of the lead fraction showed the monthly variability of ice lead, and the ice lead had a reasonable spatial distribution and was consistent with CryoSat-2 L2I data products. According to these results, the Bagging classifier can provide an essential reference for future studies of Arctic sea ice thickness and sea level estimation from HY-2B radar altimeter data.
Line Strengths and Line-Strength Gradients in S0 Galaxies

Line strengths and their gradients in Mg, Fe, and H beta have been determined for a sample of 20 SO galaxies in order to study the stellar populations of their bulges and disks and to investigate their relationship to elliptical galaxies. Data are also presented for the elliptical galaxy NGC 1700 and the E/S0 NGC 3585. We find that S0 galaxies generally follow a similar, though possibly steeper, relationship between central Mg-2 line strength and central velocity dispersion as found for elliptical galaxies. The S0 galaxies show no dependence between Fe line strengths and central velocity dispersion-similar to the behavior observed in elliptical galaxies. The central Mg/Fe ratios in the luminous S0 galaxies show an overabundance of Mg to Fe with respect to solar element ratios. The disks (at 1 h) and bulges (at 1 r(e)) show Mg/Fe ratios lower than those found in the central regions. The magnitudes of the Mg and Fe line-strength gradients within the galaxies are found to be correlated, i.e., objects with steep Mg gradients have correspondingly large Fe gradients. We infer bulge and disk gradients for the nine most edge-on galaxies for which we have both major and minor-axis profiles. The metal line strengths decrease with radius along the major and minor axes in the bulge-dominated central regions. At larger radii, however, the major-axis metal line strength profiles flatten while the minor-axis bulge profiles fall to lower values. Representative color maps in B-R are presented that display a separation between bulge and disk colors corresponding to the metal line strength profiles. Based on our Mg-2 profiles, the average metal gradient found in the disks of our subsample is Delta[Fe/H]/Delta(r/h) = -0.08 +/- 0.06, which corresponds to a reduction in the mean metallicity of the disk stellar population by less than or similar to 15% per disk scale length (h). These shallow metallicity gradients are approximately a factor of 2-3 smaller than those derived for the disks of late-type spiral galaxies from H II regions and are consistent with previous investigations that showed a trend for disk metallicity gradients to decrease toward earlier Hubble types. As inferred from our Mg and Fe line strengths, the mean size of the bulge metallicity gradients is Delta[Fe/H]/Delta log r = -0.7 +/- 0.4, which is steeper than typical elliptical galaxy gradients. Our findings do not support formation scenarios in which bulges formed either from heated disk material at late times after disk formation or through dissipationless stellar merging, as neither process includes mechanisms for producing the observed metallicity gradients. Our observations are better explained in terms of formation via dissipative collapse (or merging) at early times.
Image denoising based on wavelet transform algorithm

In this paper, a new wavelet threshold denoising algorithm has been proposed based on the correlation characteristics between layers coefficient and the inner-layer coefficient. For each wavelet coefficient, a corresponding threshold is constructed according to the wavelet coefficients between layers and layer-related features. The experimental results show that the ability of this algorithm is better than the traditional algorithm in the aspect of image denoising.
Maximum and minimum tracking performances of adaptive filtering algorithms over target weight cross correlations

This paper is concerned with studying the dependence of the tracking performance of the LMS, RLS, sign, signed regressor, and sign-sign algorithms on the cross correlations among the fluctuations of individual target weights. In practical applications, these cross correlations are usually unknown. Therefore, it is useful for design purposes to find the extreme values of the performance measures over all possible cross correlations. The paper derives, for each one of the above five algorithms, the conditions of target weight cross correlations that maximize and the ones that minimize the steady-state excess mean-square error /spl xi/ and the steady-state mean-square weight misalignment /spl eta/. The relationship between the step sizes /spl mu//sub /spl xi// and /spl mu//sub /spl eta// that minimize /spl xi/ and /spl eta/, respectively, for given target weight cross correlations is studied. Maxima and minima of /spl mu//sub /spl xi// and /spl mu//sub /spl eta// over all target weight cross correlations are found. The necessary and sufficient condition of equality of /spl mu//sub /spl xi// and /spl mu//sub /spl eta// for all target weight cross correlations is derived. A rule that maps the tracking performance measures of the LMS algorithm to the ones of the RLS algorithm is found. The necessary and sufficient condition of equality of the tracking capabilities of the RLS and LMS algorithms for all target weight cross correlations is derived. A measure of the degree of ambiguity of the tracking performance, due to ignorance of target weight cross correlations, is defined. It is found that all of the above algorithms share the same degree of ambiguity, and that this degree increases with the eigenvalue spread of the input covariance matrix.
QML ESTIMATION OF A CLASS OF MULTIVARIATE ASYMMETRIC GARCH MODELS

We establish the strong consistency and asymptotic normality of the quasi-maximum likelihood estimator (QMLE) of the parameters of a class of multivariate asymmetric generalized autoregressive conditionally heteroskedastic processes, allowing for cross leverage effects. The conditions required to establish the asymptotic properties of the QMLE are mild and coincide with the minimal ones in the univariate case. In particular, no moment assumption is made on the observed process. Instead, we require strict stationarity, for which a necessary and sufficient condition is established. The asymptotic results are illustrated by Monte Carlo experiments, and an application to a bivariate exchange rates series is proposed.
NECESSARY AND SUFFICIENT CONDITIONS FOR TOPOLOGICAL EQUIVALENCE OF THREE-DIMENSIONAL MORSE-SMALE DYNAMICAL SYSTEMS WITH A FINITE NUMBER OF SINGULAR TRAJECTORIES

The author introduces a complete topological invariant of three-dimensional Morse-Smale systems with finitely many singular trajectories, including closed trajectories, which is called the scheme of the dynamical system. Conditions for the equivalence of schemes are given, and it is shown that two systems are topological equivalent if and only if their schemes are equivalent. Figures: 4. Bibliography: 18 titles.