Miracle-dz/UniFAR-FTUs huggingface dataset:
Additive Manufacturing of Co3Fe Nano-Probes for Magnetic Force Microscopy

Magnetic force microscopy (MFM) is a powerful extension of atomic force microscopy (AFM), which mostly uses nano-probes with functional coatings for studying magnetic surface features. Although well established, additional layers inherently increase apex radii, which reduce lateral resolution and also contain the risk of delamination, rendering such nano-probes doubtful or even useless. To overcome these limitations, we now introduce the additive direct-write fabrication of magnetic nano-cones via focused electron beam-induced deposition (FEBID) using an HCo3Fe(CO)12 precursor. The study first identifies a proper 3D design, confines the most relevant process parameters by means of primary electron energy and beam currents, and evaluates post-growth procedures as well. That way, highly crystalline nano-tips with minimal surface contamination and apex radii in the sub-15 nm regime are fabricated and benchmarked against commercial products. The results not only reveal a very high performance during MFM operation but in particular demonstrate virtually loss-free behavior after almost 8 h of continuous operation, thanks to the all-metal character. Even after more than 12 months of storage in ambient conditions, no performance loss is observed, which underlines the high overall performance of the here-introduced FEBID-based Co3Fe MFM nano-probes.
High-speed electrooptic deflector and its application to picosecond pulse generation

New types of electrooptic deflectors with high speed and high efficiency, which are useful for ultrafast optical switching and ultrashort optical pulse generation, are described. These deflectors are driven by an X-band standing wave along the microstrip line on an electrooptic crystal. A time-varying spatial slope of the refractive index is induced in the crystal by the electric standing wave. As a result, the ultrafast deflection is carried out. The operation of such deflectors constructed on a LiTaO/sub 3/ crystal using a 514.5-nm CW argon laser and a 9.35-GHz driving frequency was confirmed experimentally. In addition, the optical pulse compression from CW to 9.35 GHz, 16 ps was carried out with a diffraction grating, and picking out the 18.7-GHz, 8-ps pulse train was also carried out using a slit as a temporal window. >
Atividades experimentais no ensino de física: diferentes enfoques, diferentes finalidades

In this paper were analysed the recent publications about the investigations on experimentation as a strategy of Physics teaching, with the objective of improving the understanding about the different possibilities and tendencies of these activities with an eye to subsidise the teachers and researchers activities at the high school level. The data analysis were based on the articles published between 1992 and 2001 in the Revista Brasileira de Ensino de Fisica (SBF), in its annex Fisica na Escola and also in the Caderno Catarinense de Ensino de Fisica (UFSC). The themes and some methodological aspects related with the proposals of experiments, as the applied mathematical emphasis, the intensity of directivity, the employment of new technologies and the relation to the quotidian were investigated. The results obtained show that the experimentation remain been of great interest of researchers, presenting this strategy a wide range of approaches and objectives to the Physics teaching.
Semi-supervised Discriminant Analysis with Tensor Representation ⋆

Discriminant Analysis with Tensor Representation (DATER) is a typical supervised tensor embedding methods which have been used in face recognition and behavior recognition. Commonly, the projection matrixes are obtained by maximizing the interclass scatters and simultaneously minimizing the intraclass scatters. But in practical applications, no sufficient labeled training samples with prior knowledge was provided, so unlabeled image data are eager for incorporating in subspace learning algorithm to improve the identification accuracy. In this paper, we propose a tensor space learning method, which are called Semi-supervised Discriminant Analysis with Tensor Representation (SDATER). The algorithm maximizes the separability of different classes using DATER algorithm, while preserving the local topological manifold structure and the intrinsic geometric property using Tensor Neighborhood Preserving Embedding (TNPE). Therefore, our SDATER algorithm can introduce high order tensor discriminant analysis into simi-supervised learning and avoid the curse of dimensionality problem and the small sample size problem. Experimental results demonstrate that our SDATER algorithm outperform the start-of-art methods.
Accurate Prediction of Cancer Prognosis by Exploiting Patient-Specific Cancer Driver Genes

Accurate prediction of the prognoses of cancer patients and identification of prognostic biomarkers are both important for the improved treatment of cancer patients, in addition to enhanced anticancer drugs. Many previous bioinformatic studies have been carried out to achieve this goal; however, there remains room for improvement in terms of accuracy. In this study, we demonstrated that patient-specific cancer driver genes could be used to predict cancer prognoses more accurately. To identify patient-specific cancer driver genes, we first generated patient-specific gene networks before using modified PageRank to generate feature vectors that represented the impacts genes had on the patient-specific gene network. Subsequently, the feature vectors of the good and poor prognosis groups were used to train the deep feedforward network. For the 11 cancer types in the TCGA data, the proposed method showed a significantly better prediction performance than the existing state-of-the-art methods for three cancer types (BRCA, CESC and PAAD), better performance for five cancer types (COAD, ESCA, HNSC, KIRC and STAD), and a similar or slightly worse performance for the remaining three cancer types (BLCA, LIHC and LUAD). Furthermore, the case study for the identified breast cancer and cervical squamous cell carcinoma prognostic genes and their subnetworks included several pathways associated with the progression of breast cancer and cervical squamous cell carcinoma. These results suggested that heterogeneous cancer driver information may be associated with cancer prognosis.
Characterizing mildly context-sensitive grammar formalisms

This thesis involves the study of formal properties of grammatical formalisms that are relevant to computational linguists. The formalisms which will receive the most attention share the property that they are highly restricted in their generative power. Recent research suggests that Context-Free Grammars (CFG's) lack the necessary expressive power on which to base a linguistic theory. This has led computational linguists to consider grammatical formalisms whose generative power exceeds CFG's, but only to a limited extent. We compare a number of formalisms on the basis of their weak generative capacity, as well as suggesting ways in which they can be compared on the basis of their strong generative capacity. In particular, we consider properties of their structural descriptions (or tree sets); and the types of dependencies (nested, crossed, etc.) that can be exhibited by each formalism. Several formalisms that are notationally quite different (Tree Adjoining Grammars, Head Grammars, and Linear Indexed Grammars) have been shown to be weakly equivalent. We show that Combinatory Categorical Grammars are weakly equivalent to these formalisms. The class of languages generated by these formalisms can be thought of one step up from CFG's, and we describe a number of progressions that illustrate this. The string languages generated by TAL's, HL's, CCL's and LIL's exhibit limited crossed-serial dependencies in addition to those produced by Context-Free Grammars (nested and serial dependencies). By formalizing these crossed-serial dependencies and their relationship with the nested dependencies produced by CFG's we define an infinite progression of formalisms. Our work on structural descriptions leads us to characterize a class of formalisms called Linear Context-Free Rewriting Systems (LCFRS's), which includes a wide range of grammatical formalisms with restricted power. The systems in this class have context-free derivations, and simple composition operations that are linear and nonerasing. We prove that all members of this family generate only semilinear languages that can be recognized in polynomial time.
Numerical simulation of shock propagation in one and two dimensional domains

The objective of this dissertation is to develop robust and accurate numerical methods for solving the compressible, non-linear Euler equations of gas dynamics in one and two space dimensions. In theory, solutions of the Euler equations can display various characteristics including shock waves, rarefaction waves and contact discontinuities. To capture these features correctly, highly accurate numerical schemes are designed. In this thesis, two different projects have been studied to show the accuracy and utility of these numerical schemes. Firstly, the compressible, non-linear Euler equations of gas dynamics in one space dimension are considered. Since the non-linear partial differential equations (PDEs) can develop discontinuities (shock waves), the numerical code is designed to obtain stable numerical solutions of the Euler equations in the presence of shocks. Discontinuous solutions are defined in a weak sense, which means that there are many different solutions of the initial value problems of PDEs. To choose the physically relevant solution among the others, the entropy condition was applied to the problem. This condition is then used to derive a bound on the solution in order to satisfy L2-stability. Also, it provides information on how to add an adequate amount of diffusion to smooth the numerical shock waves. Furthermore, numerical solutions are obtained using far-field and no penetration (wall) boundary conditions. Grid interfaces were also included in these numerical computations. Secondly, the two dimensional compressible, non-linear Euler equations are considered. These equations are used to obtain numerical solutions for compressible flow in a shock tube with a 90◦ circular bend for two channels of different curvatures. The cell centered finite volume numerical scheme is employed to achieve these numerical
Quasimonotone versus pseudomonotone

Under some natural hypotheses, we show that if the (Nemitsky-) operator associated with an elliptic system is pseudomonotone, then the system has to be quasimonotone. Conversely, if the system satisfies a strict quasimonotonicity condition, then an existence proof of K. -W. Zhang contains the arguments to verify the pseudomonotonicity of the operator. We present a simplified proof of this fact under more general assumptions.
Mass Transport in the Stokes Edge Wave for Constant Arbitrary Bottom Slope in a Rotating Ocean

AbstractThe Lagrangian mass transport in the Stokes surface edge wave is obtained from the vertically integrated equations of momentum and mass in a viscous rotating ocean, correct to the second order in wave steepness. The analysis is valid for bottom slope angles β in the interval 0 < β ≤ π/2. Vertically averaged drift currents are obtained by dividing the fluxes by the local depth. The Lagrangian mean current is composed of a Stokes drift (inherent in the waves) plus a mean Eulerian drift current. The latter arises as a balance between the radiation stresses, the Coriolis force, and bottom friction. Analytical solutions for the mean Eulerian current are obtained in the form of exponential integrals. The relative importance of the Stokes drift to the Eulerian current in their contribution to the Lagrangian drift velocity is investigated in detail. For the given wavelength, the Eulerian current dominates for medium and large values of β, while for moderate and small β, the Stokes drift yields the main co.
Theory of saturation spectroscopy including collisional effects

Abstract : A theory of saturation spectroscopy in three-level gas vapor systems, including collisional effects, is presented. Using a model of collisions in which they are phase-interrupting in their effect on level coherences and velocity-changing in their effect on level population densities, we calculate the absorption profile of a weak probe field on a given transition when an arbitrarily strong pump field acts on a coupled transition. Line shapes are derived for an arbitrary collision kernel describing the velocity-changing collisions, and these line shapes are evaluated for the collision kernel proposed by Keilson and Storer. Various limiting forms for the line shapes are derived and representative line shapes are displayed. Several new features of the line shapes, including collisionally-induced increased probe absorption are discussed. The line shapes are seen to reflect the various collisional processes that may occur in atomic or molecular systems. (Author)
Coupled‐Mode Laser Oscillation

A set of general equations describing the time‐dependent behavior of a laser is derived. The derivation is based on a density matrix description of a homogeneously broadened laser transition and a semiclassical treatment of the radiation field, consisting of an arbitrary number of modes. The resulting equations resemble ordinary rate and energy conservation equations but contain additional interference terms which, in general, couple all of the modes. The strength of this coupling depends on the inhomogeneity of the population inversion as well as on the mode frequencies. The energy conservation equations imply that absorption and stimulated emission in such a system can apply, strictly speaking, only collectively to the system of modes as a whole. In addition, the threshold inversion is affected by mode coupling. Stability analysis carried out in the two‐mode case indicates that a spatial inhomogeneity in the pumping rate is required for undamped oscillations. It is also concluded that coupling of off‐ax.
Admissible Control Laws for Constrained Linear Power Flow: The General Case

Linearized power flow with line flow and voltage constraints can be modeled as a system of linear inequalities depending on the power injections. When some injections are controlled by the grid operator while others are determined exogenously, robust control aims at determining grid operator's actions under imperfect system observability such that the grid state is feasible for all possible realizations of the exogenous actions. It was shown how to design and analyze such admissible control policies efficiently for the subclass of affine control laws, but this paper shows that there are important cases that require more general control policies. We show that, for the constrained linear power flow setting, general admissible control policies can always be chosen as piecewise affine (PWA) mappings. The PWA mapping can be explicitly characterized offline or control actions can be computed online by solving an optimization problem given a current observation. For the latter setup, we provide an algorithm that verifies offline that the online control scheme is admissible. This verification step is a crucial precondition to apply the online control scheme in real, safety-critical power grids. The proposed framework is demonstrated with applications to voltage regulation in active distribution grids subject to uncertain prosumers and low observability.
The Schubert calculus

An enumerative problem asks the f o l l o w i n g type of question; how many f i g u r e s ( l i n e s , planes, conies, c u b i c s , etc.) meet t r a n s v e r s e l y (or are tangent to) a c e r t a i n number of other f i g u r e s i n general p o s i t i o n ? The l a s t century saw the development of a c a l c u l u s f o r s o l v i n g t h i s problem and a l a r g e number of examples were worked out by Schubert, a f t e r whom the c a l c u l u s i s named. The c a l c u l u s , however, was not r i g o r o u s l y j u s t i f i e d , most e s p e c i a l l y i t s main p r i n c i p l e whose modern i n t e r p r e t a t i o n i s that when c o n d i t i o n s of an enumerative problem are v a r i e d continuously then the number of s o l u t i o n s i n the general case i s the same as the number of s o l u t i o n s i n the s p e c i a l case counted w i t h m u l t i p l i c i t i e s . Schubert c a l l e d i t the p r i n c i p l e of conservation of number. To date the p r i n c i p l e has been v a l i d a t e d i n the case where the f i g u r e s are l i n e a r spaces i n complex p r o j e c t i v e space, but only i s o l a t e d cases have been solved where the f i g u r e s are curved. H i l b e r t considered the Schubert c a l c u l u s of s u f f i c i e n t importance to request i t s j u s t i f i c a t i o n i n h i s f i f t e e n t h problem. We tra c e the f i r s t foundation of the c a l c u l u s due p r i m a r i l y to Lef s c h e t z , van der Waerden and Ehresmann. The i n t r o d u c t i o n i s h i s t o r i c a l , being a summary of Kleiman's ex p o s i t o r y a r t i c l e on H i l b e r t -s f i f t e e n t h problem. We describe the Grassmannian and i t s Schubert s u b v a r i e t i e s more fo r m a l l y and describe e x p l i c i t l y the homology of the Grassmannian which gives a foundation f o r the c a l c u l u s i n terms of a l g e b r a i c c y c l e s . F i n a l l y we compute two examples and b r i e f l y mention some more recent developments.
Investigations Concerning Heavy Metals Dynamics in Reynoutria japonica Houtt.-Soil Interactions

Reynoutria japonica Houtt (RJ) is an extremely invasive plant species, found nowadays in a wide range of habitats, including those polluted with heavy metals (HM). The aim of this study was to investigate HM dynamics in RJ–soil interactions in five habitats historically polluted with HM located in Baia Mare city, Romania. The concentrations of major metal elements (Cd, Cu, Pb, Zn) in plant tissues (roots, stems, leaves) and soil samples collected from the study sites were analyzed via portable ED-XRF spectroscopy (converted), and the translocation factor (TF) and bioconcentration factor (BCF) were calculated. The mean values of HM in soil samples collected from the study sites exceeded the threshold limit values established by Romanian legislation. Generally, the highest concentration of Cd was recorded in the above-ground part of the plant (stem and leaves), while for Cu, Pb and Zn, the highest values (with few exceptions) were recorded in the root. The metal transfer was highly effective from soil to RJ, such that all four of the HM studied exceeded the normal range of metals in a plant. Analysis of metal concentrations in plant tissues showed an efficient movement of Cd and Zn to the above-ground parts of the plant, a tendency particularly pronounced in the case of Cd (TF and BCF > 1), while Pb was the least bioaccumulated HM. It may be concluded that RJ is able to tolerate high concentrations of HM, being a good phytoextractor for Cd and Zn.
Antibonding molecular orbitals under the influence of elliptically polarized intense light

The strong-field dynamics of diatomic molecules with antibonding valence orbitals is investigated within classical and quantum mechanical model calculations. Due to the orbital symmetry, ejected electrons never return to the core if a linearly polarized laser field acts perpendicularly to the molecular axis. However, elliptical polarization can be used to achieve recollision so that high-order above-threshold ionization and high-order harmonic generation become maximal at nonzero ellipticity. Smaller ellipticities favour higher harmonic orders. For given ellipticity the probability for electron recollisions depends strongly on the orientation of the molecule. Thus, ellipticity can be used as a control parameter to select a range of orientations for recollision-induced processes.
Data Acquisition Control for UAV-Enabled Wireless Rechargeable Sensor Networks

In the realm of Internet of Things (IoT), wireless sensor networks (WSNs) have been the subject of ongoing research into the use of energy harvesting to capture ambient energy, and wireless power transfer (WPT) via a mobile charger to overcome the energy limitations of sensors. Moreover, to mitigate energy imbalance and reduce the number of hops, strategies have been developed to leverage cars or unmanned aerial vehicles (UAVs) as mobile sinks. The primary objective of this work is to increase network lifetime by reducing energy consumption of hotspot nodes and increasing the amount of data acquired from all sensors in an environment that combines the methods mentioned above.To achieve this objective, the proposed method involves developing multiple minimum depth trees (MDTs) for all nodes, considering the energy of the UAV and sensor nodes. Parent nodes prevent their own energy depletion and ensure data transmission without imbalance by adaptively controlling the data sensed at the nodes and their child nodes. Consequently, the energy depletion of nodes in hotspots is prevented, more sensory data is acquired, and balanced data collection from all nodes is achieved. Simulation results demonstrate that the proposed scheme outperforms other state-of-the-art methods in terms of reduced energy depletion, increased network connectivity, and the amount of data collected at the sink node. This scheme will be applied to applications that collect environmental data outdoors, such as climate measurement, to collect data uniformly and increase the lifespan of the network, thereby reducing network maintenance costs while collecting data effectively.
Fast Simulation of Analog Spiking Neural Network With Device Non-Idealites

We present a method for spiking neural network simulation with hardware realistic device non-idealities present in the neuron and synapse circuits as an alternative to time-consuming spice simulation. Neuromorphic machine learning algorithms for spiking neural networks are often simulated with an ideal mathematical description of spiking neurons and synapses. However, silicon implementations of spiking neurons differ significantly from their ideal mathematical models because of device non-idealities and restrictions in the range of device operation. These non-idealities affect the performance of chip implementations of spiking networks. The dynamical system phase plane of the neuron and synapse circuit is used to create a compact representation of the neuron dynamics that captures device non-idealities for simulation of spiking neural networks. The proposed method would allow hardware-aware optimization of neuromorphic algorithms using standard machine learning tools and provide simulated network prediction close to what would be expected from a chip implementation.