Miracle-dz/UniFAR-FTUs huggingface dataset:
A Comparative Analysis of Neural Networks in Anticipatory Transportation Planning

Anticipatory transportation planning (ATP) problems can be formalized as sequential decision-making problems under uncertainty, where expected future consequences are included in current decision-making. Approximate dynamic programming (ADP) and reinforcement learning (RL) are popular machine learning techniques used for sequential decision-making problems, often used in conjuction with a parametric value function approximation (VFA). The most widely used form of such a VFA is linear regression (LVFA), although we may use more complex, non-linear predictors to represent a VFA, e.g., neural network VFAs (NNVFA). Alternatively, we may represent the policy directly, using a neural network policy function approximation (NNPFA). The use of (deep) neural networks (NNVFA or NNPFA) seems promising but is underex-posed in ATP research. The possible advantages of NNVFAs or NNPFAs over LVFAs are poorly understood, as are the disadvantages. Therefore, we compare three different policies: (i) LVFA, (ii) NNVFA, and (iii) NNPFA and explore whether neural network based policies can deliver value beyond LVFAs, and if so, what the accompanying disadvantages are. This paper presents a structured comparison in terms of performance, robustness, and computational efficiency. We compare policies on several stylized variants of the dynamic vehicle routing problem with stochastic customer requests, which is a much studied and typical ATP problem. We also compare using a realistic case that involves the routing of robots in an automated storage an retrieval system (AS/RS) warehouse of a Norwegian electronic equipment retailer. We show that (i) whether neural network policy based approaches or linear based VFAs are better depends subtly on problem characteristics, (ii) the potential ability of neural networks to improve upon LVFAs is drawn from their ability to include interaction effects between features, but (iii) comes at the expense of longer computational times. Furthermore, we show that (iv) in most cases, neural network PFAs (NNPFAs) outperform neural network VFAs (NNVFAs), but NNVFAs are significantly faster and more robust to problem changes.
Measurement of Lattice Temperature of Silicon during Pulsed Laser Annealing

A classical time-of-flight method was used to determine the temperature of evaporated Si atoms and thus the lattice temperature of Si during pulsed laser annealing. The resulting temperatures between 1200 and 3000 K for energy densities between 1.0 and 2.5 J/${\mathrm{cm}}^{2}$ clearly support a strictly thermal annealing model including melting of the surface region of Si.
Ratio of Land Consumption Rate to Population Growth Rate in the Major Metropolitan Areas of Romania

In 2015, the 2030 Agenda for Sustainable Development was adopted by all United Nations Member States and includes a set of 17 Sustainable Development Goals. The indicator, “Ratio of land consumption rate to population growth rate” (indicator 11.3.1) was proposed for the monitoring of urban development. The present study proposes the analysis of the built-up space evolution in relation to the demographic growth in the main metropolitan areas of Romania using the 11.3. 1 indicator. Land consumption rate and population growth rate (LCRPGR) is used to assess the sustainability of urban growth, which takes into account both the change in the built-up area and in the population. LCRPGR is calculated as the ratio of land consumption rate (LCR) and the population growth rate (PGR). The analysis was conducted at the metropolitan area level for the 2006–2009, 2009–2015 and 2015–2020 periods. LCR and PGR proved to be very useful indicators for the monitoring of the intensity of built-up changes in the eight metropolitan areas both in time and in space and are useful for the local and central administrations, in both the context of achieving the sustainable development targets and goals and in conducting urban design and planning.
Early Readmission and Reoperation After Percutaneous Transforaminal Endoscopic Decompression for Degenerative Lumbar Spinal Stenosis: Incidence and Risk Factors

Purpose: To identify the incidence rates and risk factors for early readmission and reoperation after percutaneous transforaminal endoscopic decompression (PTED) for degenerative lumbar spinal stenosis (DLSS). Patients and Methods: A total of 1011 DLSS patients who underwent PTED were retrospectively evaluated. Of them, 58 were readmitted, and 31 underwent reoperation. The patients were matched with 174 control patients to perform case-control analyses. The clinical and preoperative imaging data of each patient were recorded. Univariate analyses were performed using independent sample t -tests and Fisher’s exact tests. Furthermore, the risk factors for early readmission and reoperation were analyzed using multivariate logistic regression analyses. Results: The incidence rates of readmission and reoperation within 90 days after PTED were 5.7% and 3.1%, respectively. Age (odds ratio [OR]=1.054, p=0.001), BMI (OR=1.104, p=0.041), a history of lumbar surgery (OR=3.260, p=0.014), and the number of levels with radiological lumbar foraminal stenosis (LFS, OR=2.533, p<0.001) were independent risk factors for early readmission. The number of levels with radiological LFS (OR=5.049, p<0.001), the grade of surgical-level facet joint degeneration (OR=2.010, p=0.023), and a history of lumbar surgery (OR=10.091, p<0.001) were independent risk factors for early reoperation. Conclusion: This study confirmed that aging, a higher BMI, a history of lumbar surgery, and more levels with radiological LFS were associated with a higher risk of early readmission. More levels with radiological LFS, a higher grade of surgical-level facet joint degeneration, and a history of lumbar surgery were predictors of early reoperation. These results are helpful in patient counseling and perioperative evaluation of PTED.
On Usable Security and Verified Password Managers

Password Managers (PMs) are useful tools to manage pass-words but they are not widely used. Studies indicate usability problems and distrust from users as the reasons for the low adoption of PMs. As such, we propose extending an existing PM by implementing relevant usability best practices and increasing transparency by educating users about how PMs work. This project is part of the PassCert research project, which aims to build a formally verified PM. Therefore, another goal is to explore ways that effectively convey to users the formally verified properties. We performed user studies that suggest that our solution improves the usability of the PM and that we were able to convey relevant information about its formally verified features. We contribute with the first study on users perceptions of formal verification on PMs and hope that our findings can help the formal verification security community better communicate with end-users
Approximate inverse systems of compacta and covering dimension.

Approximate inverse systems of metric compacta are introduced and studied. The bonding maps in these systems commute only up to certain controlled values. With every such system X = (X a , ε a , p aa ' > A) are associated a limit space X and projections p a : X —> X a A compact Hausdorff space X has covering dimension dim X < n if and only if it can be obtained as the limit of an approximate inverse system of compact polyhedra of dimension < n. The analogous statement for usual inverse systems is known to be false.
MOSSBAUER STUDY OF HYPERFINE FIELDS AND ISOMER SHIFTS IN THE Fe-Rh ALLOYS

Hyperfine fields and isomer shifts of Fe/sup 57/ in the Fe-Rh system were investigated by the Mossbauer technique in the composition range between 0 and 52 at. % Rh. When the Rh concentration exceeds 20%, chemical ordering of CsCl type develops and two distinct hyperfine fields are observed, corresponding to Fe on Fe sites and Fe on Rh sites. For example, H/sub i/(I) = 277 kOe and H/sub i/ (II) = 384 kOe in an alloy containing 48% Rh. Neutron diffraction study of this alloy gave FeI = 3.2 /sub B/, but no direct measurement is available for FeII. It is suggested that Fe II, which is surrounded by 8 Fe nearest neighbors, may have a smalier magnetic moment than FeI despite its higher hyperfine field. The alloy with 50% Rh transforms, on cooling, from ferromagnetic to antiferromagnetic at 65 c- C. At this phase transition the hyperfine field shows a disconti nuous decrease of 14 kOe. (auth)
A likelihood ratio test for a shift in the lifelength distribution

In this article, we discuss the problem of detecting the effect of a shock occurring in a life test experiment involving n test specimens. It is assumed that a shock occurs at the (n – r)th failure where r is known. Such a shock is suspected to have altered the parameters of the remaining lifelengths of the surviving specimens. Under this set-up, a test based on likelihood ratio criterion is discussed. It has been shown that when the lifelength distribution is exponential, the null distribution of the proposed test statistic is beta of type I with parameters r and (n – r). The distribution of the proposed test statistic under alternate hypothesis and the exact form of the power function have been derived. A power comparison of the proposed test statistic is also made with a prediction-based test statistic discussed in the literature.
Radial Positive Definite Functions Generated by Euclid's Hat

Radial positive definite functions are of importance both as the characteristic functions of spherically symmetric probability distributions, and as the correlation functions of isotropic random fields. The Euclid's hat functionhn(? x? ),x? Rn, is the self-convolution of an indicator function supported on the unit ball in Rn. This function is evidently radial and positive definite, and so are its scale mixtures that form the classHn. Our main results characterize the classesHn,n? 1, andH∞=? n? 1Hn. This leads to an analogue of Polya's criterion for radial functions on Rn,n? 2: If? :[0,∞)? R is such that? (0)=1,? (t) is continuous, limt? ∞? (t)=0, and(? 1)kdkdtk[? (t)]is convex fork=[(n? 2)/2], the greatest integer less than or equal to (n? 2)/2, then? (? x? ) is a characteristic function in Rn. Along the way, side results on multiply monotone and completely monotone functions occur. We discuss the relations ofHnto classes of radial positive definite functions studied by Askey (Technical Report No. 1262, Math. Res. Center, Univ. of Wisconsin? Madison), Mittal (Pacific J. Math.64(1976), 517? 538), and Berman (Pacific J. Math.78(1978), 1? 9), and close with hints at applications in geostatistics.
A spectroscopic study into accretion in Herbig Ae/Be stars

This thesis presents a spectroscopic study of the stellar properties, accretion rates, and emission lines of 91 Herbig Ae/Be stars. Medium resolution spectra and optical photometry are used to spectrally type a sample of 91 Herbig Ae/Be stars in a homogeneous fashion. Stellar parameters of temperature, surface gravity, mass, radius, luminosity, distance, age, and reddening are determined using the above in combination with pre-main sequence tracks. The temperatures are in agreement with previous assessments, while new distance and mass estimates for some objects constitute a large improvement. Measurements of the UV-excess across the Balmer jump region are made, and they are modelled within the context of magnetospheric accretion. Accretion rates are derived from the fitting. Seven Herbig Be stars could not be fitted within this context, suggesting a possible breakdown of magnetospheric accretion towards the higher mass Herbig Ae/Be stars. Different relationships between accretion rate and age are observed for the cases of Herbig Ae stars and Herbig Be stars; this is suspected to be an evolutionary effect of both the star approaching the main sequence and the pre-main sequence lifetime of the star itself. Line luminosities are measured for 32 different emission lines ranging from 4000-21700 Angstrom. All lines are observed to be correlated with the accretion luminosity, providing multiple new accretion diagnostics. The mean power-law relationship between accretion luminosity and line luminosity is observed to be the same between HAeBes and CTTs, within the errors. However, a line by line comparison between the two, demonstrates deviation in 80% of comparable lines. This deviation appears greatest in the Herbig Be regime. Further investigation is required into the line profiles and current scatter observed in relationships for different classes of pre-main sequence stars.
Continuous and first-order wetting transition from the van der Waals theory of fluids

The transition between incomplete wetting and complete wetting of an attractive substrate in contact with a gas at gas-liquid coexistence is studied. Within the framework of the systematic van der Waals (mean-field) theory of fluids, it is shown that both a continuous wetting transition, as found by Sullivan, and a first-order transition with a prewetting line, previously found by other methods, are possible. The relative magnitude of the various characteristic lengths in the problem is shown to be of relevance in this context. Beyond the model calculations, purely thermodynamic arguments show that in general the prewetting line, if it exists, joins the bulk coexistence line tangentially in the $T\ensuremath{-}\ensuremath{\mu}$ phase plane. The manner in which the difference in slope vanishes as bulk coexistence is approached is closely related to the nature of the forces.
Some remarks on the problem of source identification from boundary measurements

We consider the problem of determining a source term from boundary measurements, in an elliptic problem. In general, this source is unattainable except for its harmonic component. We then turn ourselves to the problem in some special cases when a priori information is available. In particular, when separation of variables is possible.
The adjoint process of a diffusion with reflecting barrier

Nelson [8] introduced the notion of the adjoint process and discussed the adjoint process of a recurrent diffusion without boundary. We shall construct the adjoint process, which is unique by the uniqueness of its invariant measure, of a diffusion with reflecting barrier, a typical recurrent diffusion with boundary and prove that it is again a diffusion with reflecting barrier and that the results proved by Nelson [8] for self-adjoint diffusion remain valid. Then, we shall determine the adjoint process of "the Markov process on the boundary" of the diffusion with reflecting barrier introduced by Ueno [11] (cf. [3]) in connection with the construction of diffusions with WentzelPs boundary conditions. A comment will be given about processes with more general boundary conditions. The author wishes to express his thanks to Prof. H. Umegaki, Mr. T. Ueno, Mr. K. Satδ, and Prof. N. Ikeda who took interests in the problem and gave him many suggestions in preparing this paper.
Faint emission lines in the spectrum of the Orion Nebula and the abundances of some of the rarer elements

CCD spectra were obtained of a region just north of the Trapezium in NGC 1976, the Orion Nebula, in overlapping exposures covering the wavelength region λλ3180-11000. Approximately 225 emission lines were measured at a resolution of about 6 A. A total of 35 H I lines and 57 He I lines were identified. Most of their measured intensities, corrected for interstellar extinction, agree relatively well with the recombination-line theory. At the faintest levels there are discrepancies, probably resulting from observational uncertainties
Mixed Type Duality for Multiobjective Variational Problems

The concept of mixed-type duality has been extended to the class of multiobjective variational problems. A number of duality relations are proved to relate the efficient solutions of the primal and its mixed-type dual problems. The results are obtained for ρ-convex (generalized ρ-convex) functions. These studies have been generalized to the case of ρ-invex (generalized ρ-invex) functions. Our results apparently generalize a fairly large number of duality results previously obtained for finite-dimensional nonlinear programming problems under various convexity assumptions.
SURFACE PHOTOMETRY OF LOW SURFACE BRIGHTNESS GALAXIES

Low surface brightness (LSB) galaxies are galaxies dominated by an exponential disc whose central surface brightness is much fainter than the value of mu(B)(0) = 21.65 +/- 0.30 mag arcsec(-2) found by Freeman. In this paper we present broadband photometry of a sample of 21 late-type LSB galaxies. The median central surface brightness of the sample is mu(B)(0) = 23.2 mag arcsec(-2) and the median scale length is 3.2 kpc, showing that LSB galaxies are normal-sized galaxies. We find colours that are comparable to or bluer than those of the more widely studied 'normal' high surface brightness (HSB) galaxies. LSB galaxies are therefore not faded discs that have no current star formation. The colours cannot on the other hand be ascribed entirely to metallicity effects, but we can explain them by assuming a sporadic star formation rate scenario. LSB galaxies hence appear to be unevolved and quiescent objects, which give us an insight into the evolution of galaxies in an unperturbed environment.
Surface Structure and Three-Dimensional Motion from Image Flow Kinematics

This study concerns a new formulation and method of solu tion of the image flow problem. It is relevant to the maneu vering of a robotic system through an environment containing other moving objects or terrain. The two-dimensional image flow is generated by the relative rigid-body motion of a smooth, textured object along the line of sight to a monocular camera. By analyzing this evolving image sequence, we hope to extract the instantaneous motion (described by six degrees of freedom) and local structure (slopes and curvatures) of the object along the line of sight. The formulation relates a new local representation of an image flow to object motion and structure by twelve nonlinear algebraic equations. The repre sentation parameters are given by the two components of image velocity, three components of rate of strain, spin, and six independent image gradients of rate of strain and spin, evaluated at the point on the line of sight. These kinematic variables are motivated by the deformation of a finite element of flowing continuum. A method for solving these equations was devised and successfully implemented on a VAX com puter. A number of examples were explored revealing two classes of ambiguous scenes (i.e., nonunique solutions are ob tained). A sensitivity analysis was conducted to estimate noise levels in the representation parameters that still yield acceptable solutions; indications are that the method is quite stable. Finally, an approach is suggested by which the kine matic variables may be extracted from evolving contours in an image sequence.
The IRAS bright galaxy sample. II - The sample and luminosity function

A complete sample of 324 extragalactic objects with 60 μm flux densities greater than 5.4 Jy has been selected from the IRAS catalogs. Only one of these objects can be classified morphologically as a Seyfert nucleus; the others are all galaxies. The median distance of the galaxies in the sample is ~ 30 Mpc, and the median luminosity vL,(60 μm) is ~ 2 x 10^(10) L_☉ . This infrared selected sample is much more "infrared active" than optically selected galaxy samples. The range in far-infrared luminosities of the galaxies in the sample is 10^8 L_☉ -2 x 10^(12) L_☉ The far-infrared luminosities of the sample galaxies appear to be independent of the optical luminosities, suggesting a separate luminosity component. As previously found, a correlation exists between 60 μm/100 μm flux density ratio and far-infrared luminosity. The mass of interstellar dust required to produce the far-infrared radiation corresponds to a mass of gas of 108-10^(10) M_☉ for normal gas to dust ratios. This is comparable to the mass of the interstellar medium in most galaxies. The infrared luminous galaxies are found to be an important component of extraglactic objects, being the most numerous objects in the local universe at luminosities L > 10^(11) L_☉, and producing a luminosity density of ~ that of the observed starlight in normal galaxies. Approximately 60%-80% of the far-infrared luminosity of the local universe is likely attributed to recent or ongoing star formation. If the infrared active phase (L_(FIR) > 10^(11) L_☉ ) is a nonrecurring event of duration less than 108 yr in galaxy evolution, then more than 10%, and perhaps all of the galaxies with blue luminosities greater than 10^(10) L_☉ must undergo such an event.
Observation and Modeling of the Solar Transition Region. I. Multi-Spectral Solar Telescope Array Observations

We report on observations of the solar atmosphere in several extreme-ultraviolet and far-ultraviolet bandpasses obtained by the Multi-Spectral Solar Telescope Array, a rocket-borne spectroheliograph, on flights in 1987, 1991, and 1994, spanning the last solar maximum. Quiet-Sun emission observed in the 171-175 Å bandpass, which includes lines of O V, O VI, Fe IX, and Fe X, has been analyzed to test models of the temperatures and geometries of the structures responsible for this emission. Analyses of intensity variations above the solar limb reveal scale heights consistent with a quiet-Sun plasma temperature of 500,000 ≤ Te ≤ 800,000 K. The structures responsible for the quiet-Sun EUV emission are modeled as small quasi-static loops. We submit our models to several tests. We compare the emission our models would produce in the bandpass of our telescope to the emission we have observed. We find that the emission predicted by loop models with maximum temperatures between 700,000 and 900,000 K are consistent with our observations. We also compare the absolute flux predicted by our models in a typical upper transition region line to the flux measured by previous observers. Finally, we present a preliminary comparison of the predictions of our models with diagnostic spectral line ratios from previous observers. Intensity modulations in the quiet Sun are observed to occur on a scale comparable to the supergranular scale. We discuss the implications that a distribution of loops of the type we model here would have for heating the local network at the loops' footpoints.
Experimental Investigation of the Wall-Effect on a Cylindrical Obstacle Moving in a Viscous Fluid at Low Reynolds Numbers

The force and moment acting on a cylindrical obstacle moving in a viscous fluid bounded by two parallel plane walls are investigated experimentally at Reynolds numbers ranging from 10 -1 to 10 -5 . The important points resulting from the experiments are that (1) the drag and the lift coefficients are exactly proportional to the reciprocal of the Reynolds number for a fixed wall distance; (2) the minimum drag is obtained when the obstacle is located halfway between the walls and the central line between the two walls; (3) the minimum lift is obtained when the obstacle is located on the central line between the two walls; (4) when δ (the distance of the obstacle from a wall) is small, a small change in the incidence produces a large change in the movement of the center of pressure; (5) for a fixed incidence, the center of pressure moves forward first, then moves backward as δ is increased; (6) the streamline pattern is unaltered even if the direction of motion is reversed.
EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTIONS FOR SECOND-ORDER STURM-LIOUVILLE AND MULTI-POINT PROBLEMS ON TIME SCALES

In this paper, a class of second-order boundary value problems with Sturm-Liouville boundary conditions or multi-point conditions is considered. Some existence and uniqueness theorems of positive solutions of the problem are obtained by using monotone iterative technique, the iterative sequences yielding approximate solutions are also given. The results are illustrated with an example.