Miracle-dz/UniFAR-FTUs huggingface dataset:
Prediction of Compressive Strength for Heterogeneous Mortars from Drilling Resistance Data

ABSTRACT The characterization of historic mortars applied in construction is required in many situations, namely for their conservation. In this sense, the drilling resistance test has been being explored by the scientific community, since it has the unique feature of assessing the material strength in depth with very low intrusion. However, the drilling profiles returned by heterogeneous and weak mortars are very irregular which has been considered a limitation of the technique. This article discusses the reasons for the reported irregularity, showing that this supposed drawback is an inevitable outcome in the case of heterogeneous materials and that the statistical analysis of the drilling data can provide important information on the material characteristics. Additionally, it is shown that compressive strength obtained in conventional tests is also very affected by the material’s heterogeneity. A prediction model for compressive strength is established from drilling data collected on 16 low-strength mortars of diverse strength and heterogeneity degrees. This model, applicable to mortars with compressive strength values below 4–5 MPa, showed a mean error of less than 0.5 MPa. Thus, it is possible to predict the compressive strength for a large number of lime-based mortars with a reasonable confidence. The accuracy of the model is then demonstrated on a different set of mortar specimens, composed of six test cases.
Penrose limits and Green–Schwarz strings

We discuss the Green–Schwarz action for type IIB strings in general plane-wave backgrounds obtained as Penrose limits from any IIB supergravity solutions with vanishing background fermions. Using the normal-coordinate expansion in superspace, we prove that the light-cone action is necessarily quadratic in the fermionic coordinates. This proof is valid for more general pp-wave backgrounds under certain conditions. We also write down the complete quadratic action for general bosonic on-shell backgrounds in a form in which its geometrical meaning is manifest both in the Einstein and string frames. When the dilaton and 1-form field strength are vanishing, and the other field strengths are constant, our string-frame action reduces, up to conventions, to the one which has been written down using the supercovariant derivative.
A microstrip antenna with reduced in-band and out-of-band radar cross-section

This paper proposes a microstrip antenna with reduced in-band and out-of-band radar cross-section (RCS) by subtracting the area of weak scattered current on the ground plane. Fourteen square slots were subtracted from the ground plane, reducing in-band and out-of-band RCS while maintaining radiation performance. Modified and reference antenna surface current distributions were simulated and analyzed in radiating and scattering modes. Two antenna prototypes were fabricated and measured to verify the simulation. The proposed antenna RCS was reduced compared with the reference antenna in the frequency range 1–4.4 GHz, including in-band and out-of-band frequency bands. Maximum in-band and out-of-band RCS reduction was 16.3 dBsm at the working frequency, and 19.3 dBsm at 3.4 GHz, respectively
Photothermal depth profiling: analysis of reconstruction errors

The accuracy of photothermal depth profiling of the thermal conductivity profile of thermally inhomogeneous materials is discussed in detail. The reconstruction error is statistically analysed as a function of depth and noise, for different classes of profiles. The analysis is done in the framework of reconstructions obtained by a neural network approach, thermal wave backscattering theory and a method which is based on a statistical sampling of the chi-squared function in a restricted part of the profile space. The latter analysis yields confidence intervals for the reconstructions.
Power extraction problem in the externally pumped 16 μm gasdynamic lasers: modelling and optimization

Power extraction problem in the gasdynamic lasers is studied by developing a quasi-one-dimensional model. Flow variables and characteristic parameters of the 16 μm output beam are obtained by numerical calculations. It is shown numerically that this type of the gasdynamic lasers can deliver a large amount of energy in high repetition rate. Based on this model, the output energy of the laser is optimized by employing the variational method. The most important parameter, the optimal nozzle-shape, is obtained by defining the family of optimal shapes. It is shown that the supersonic part of each member of this family consists of an acceleration part, an uniformization part which is a curved surface and is smoothly connected to the first part, and a relaxation duct. Finally, numerical optimization with respect to several parameters is carried out.
A Fuzzy Gravitational Search Algorithm to Design Optimal IIR Filters

The goodness of Infinite Impulse Response (IIR) digital filters design depends on pass band ripple, stop band ripple and transition band values. The main problem is defining a suitable error fitness function that depends on these parameters. This fitness function can be optimized by search algorithms such as evolutionary algorithms. This paper proposes an intelligent algorithm for the design of optimal 8th order IIR filters. The main contribution is the design of Fuzzy Inference Systems able to tune key parameters of a revisited version of the Gravitational Search Algorithm (GSA). In this way, a Fuzzy Gravitational Search Algorithm (FGSA) is designed. The optimization performances of FGSA are compared with those of Differential Evolution (DE) and GSA. The results show that FGSA is the algorithm that gives the best compromise between goodness, robustness and convergence rate for the design of 8th order IIR filters. Moreover, FGSA assures a good stability of the designed filters.
EFFECT OF ULTRAVIOLET-C RADIATION COMBINED WITH UNCONVENTIONAL ATMOSPHERE PACKAGING ON THE QUALITY OF FRESH-CUT ARUGULA (ERUCA SATIVA MILL.)

The combined effects of ultraviolet (UV) light C (0.34 to 20.13 kJ/l 2 ) and superatmospheric O2 (>85%) packaging on the respiration rate, atmospheric composition, microbiological growth and nutritional quality of fresh-cut arugula stored for 10 days at 5C were studied. All treatments performed under increased O2 levels exhibited a reduction in the respiration rate throughout the cold storage. High microbial load of the raw material were found. UV-C radiation enabled an initial reduction of about 1 and 1.5 log units on mesophilic and psychrotrophic counts, respectively. However, this treatment was not effective for mold control. In addition, a noticeable increase occurred in the total antioxidant capacity and polyphenol content without affecting the visual appearance of the leaves. UV-C radiation, as a sanitizing method, in combination with superatmospheric O2 conditions maintains the overall quality of fresh-cut arugula and is a feasible alternative to industrial-scale enforcement.
Disaggregated Servers for Future Energy Efficient Data Centres

The popularity of the Internet and the demand for 24/7 services uptime is driving system performance and reliability requirements to levels that today’s data centres can no longer support. This thesis examines the traditional monolithic conventional server (CS) design and compares it to a new design paradigm known as disaggregated server (DS). The DS design arranges data centres resources in physical pools such as processing, memory and IO module pools; rather than packing each subset in a single server. In this work, we study energy efficient resource provisioning and virtual machine (VM) allocation in the DS based data centres compared to CS based data centres. First, we developed a mixed integer linear programming (MILP) model to optimise VM allocation for DS based data centre. Our results indicate that considering pooled resources yields up to 62% total saving in power consumption compared to the CS approach. Due to the MILP high computational complexity, we developed an energy efficient, fast and scalable resource provisioning heuristic (EERP-DS), based on the MILP insights, with comparable power efficiency to the MILP. Second, we extended the resources provisioning and VM allocation MILP to include the data centre communication fabric power consumption. The results show that the inclusion of the communication fabric still yields considerable power savings compared to the CS approach, up to 48% power saving. Third, we developed an energy efficient resource provisioning for DS with communication fabric heuristic (EERP-DSCF). EERP-DSCF achieved comparable results to the second MILP and with it we can extend the number of served VMs where the MILP scalability for big number of VMs is challenging. Finally, we present our new design for the photonic DS based data centre architecture supplemented with a complete description of the architecture components, communication patterns and some recommendations for the design implementation challenges.
Tracing the Mass during Low-Mass Star Formation. I. Submillimeter Continuum Observations

We have obtained 850 and 450 μm continuum maps of 21 low-mass cores with SEDs ranging from pre-protostellar to Class I (18 K < Tbol < 370 K), using SCUBA at the JCMT. In this paper we present the maps, radial intensity profiles, and photometry. Pre-protostellar cores do not have power-law intensity profiles, whereas the intensity profiles of Class 0 and Class I sources can be fitted with power laws over a large range of radii. A substantial number of sources have companion sources within a few arcminutes (two out of five pre-protostellar cores, nine out of 16 Class 0/I sources). The mean separation between sources is 10,800 AU. The median separation is 18,000 AU including sources without companions as a lower limit. The mean value of the spectral index between 450 and 850 μm is 2.8 ± 0.4, with pre-protostellar cores having slightly lower spectral indices (2.5 ± 0.4). The mean mass of the sample, based on the dust emission in a 120'' aperture, is 1.1 ± 0.9 M☉. For the sources fitted by power-law intensity distributions (Iν(b)/Iν(0) = (b/b0)m), the mean value of m is 1.52 ± 0.45 for Class 0 and I sources at 850 μm and 1.44 ± 0.25 at 450 μm. Based on a simple analysis, assuming the emission is in the Rayleigh-Jeans limit and that Td(r) ∝ r-0.4, these values of m translate into power-law density distributions (n ∝ r-p) with p ~ 2.1. However, we show that this result may be changed by more careful consideration of effects such as beam size and shape, finite outer radii, more realistic Td(r), and failure of the Rayleigh-Jeans approximation.
Performance Prediction of a Slender Half-Displacement Passenger Craft for Inland Navigation

The design of a small passenger craft for Venice is presented. The paper deals with hydrodynamic aspects mainly concerning resistance prediction in shallow water for subcritical, critical and supercritical regimes. Open literature usually provides methods for the subcritical regime only. Here, a procedure for the estimation of added resistance in subcritical, critical and supercritical regimes is presented within the slender body approximation. The developed procedure is suitable to be used in the early design stage to predict a preliminary speed-power curve. A test case based on the designed half-displacement craft is thoroughly exposed.
Calibration of the MAGIC Telescope Using Muon Ring Images

The new 17m MAGIC telescope will operate at extremely low energy threshold for Air Cherenkov detectors. In order to restore primary spectra, it is necessary to have an absolute light calibration of the telescope camera. A system for such optical calibration is already realized in the MAGIC project. One can use muon ring images as another possibility to perform the calibration. Cherenkov light from local muons and gamma-induced showers has the similar spectrum. Parameters of muon (energy, impact parameter, inclination angle) can be obtained from the muon ring image. Using these muon parameters one can calculate the total amount of Cherenkov light in the telescope camera analytically. Thus, a conversion factor from photons to ADC count can be determined. In this report we present a method of the MAGIC telescope calibration with muon rings.
Theoretical analysis of the processes involved in lightning attachment to earthed structures

A theoretical analysis is presented for the processes involved in natural lightning attachment to earthed structures. This analysis is based on physical criteria for upward leader inception and propagation during the approach of the downward lightning leader. Analytical expressions for the equivalent voltages and their time variation are obtained for earthed structures before and after upward leader inception. Equivalent voltages in lightning rods of varying height are calculated for different values of the peak stroke current of lightning, taking into account the process of upward leader development. Significant values of equivalent voltages and their derivatives at the final jump phase of a downward leader are predicted. It is shown that there is a time interval between the moment of upward leader inception and the time when the upward leader propagation condition is fulfilled. The implications of these results for testing in a high voltage laboratory are also discussed.
Holographic gratings recorded in polymer hydrogels - an original application as a sensor in aqueous environment

The degree of swelling of a polymer hydrogel depends on the aqueous solution in which it is immersed, among other factors. When a volume phase hologram is engraved in a hydrogel film, the dependence of its diffraction efficiency on osmosis in saline solution can be used as a probe for measuring the concentration of the solute. The sensitivity of this in-line control technique is better than 20 mg of KBr.
Perturbation theory approach for the power spectrum: from dark matter in real space to massive haloes in redshift space

We investigate the accuracy of Eulerian perturbation theory for describing the matter and galaxy power spectra in real and redshift space in light of future observational probes for precision cosmology. Comparing the analytical results with a large suite of N-body simulations (160 independent boxes of 13.8 (Gpc/h)3 volume each, which are publicly available), we find that re-summing terms in the standard perturbative approach predicts the real-space matter power spectrum with an accuracy of ≲2% for k ⩽ 0.20 h/Mpc at redshifts z≲1.5. This is obtained following the widespread technique of writing the resummed propagator in terms of 1-loop contributions. We show that the accuracy of this scheme increases by considering higher-order terms in the resummed propagator. By combining resummed perturbation theories with several models for the mappings from real to redshift space discussed in the literature, the multipoles of the dark-matter power spectrum can be described with sub-percent deviations from N-body results for k ⩽ 0.15 h/Mpc at z≲1. As a consequence, the logarithmic growth rate, f, can be recovered with sub-percent accuracy on these scales. Extending the models to massive dark-matter haloes in redshift space, our results describe the monopole term from N-body data within 2% accuracy for scales k ⩽ 0.15 h/Mpc at z≲0.5; here f can be recovered within < 5% when the halo bias is known. We conclude that these techniques are suitable to extract cosmological information from future galaxy surveys.
Performance Characteristics of the Solar-B Spectro-Polarimeter

The Focal Plane Package (FPP) of the Solar Optical Telescope (SOT) includes the first precision Spectro-Polarimeter (SP) for solar space observations. The FPP/SP will provide high precision measures of the vector magnetic field in the solar photosphere. Here we present some as-built performance specifications for the entire system of telescope + polarimeter. The FPPSP system represents significant gains in several aspects over existing spectropolarimetric systems; notably, angular resolution, polarimetric accuracy, spectral purity, and most importantly, temporal continuity of stable, high angular resolution. In this short summary of the poster, a few of the performance characteristics of the SP are presented.
A time–distance domain transform method for Lamb wave dispersion compensation considering signal waveform correction

In Lamb wave identification, time–distance domain mapping (TDDM) is one of the most popular methods for dispersion compensation. However, it is found that the processed signal waveforms are easily deformed by TDDM. To improve the compensation effect, a time–distance domain transform (TDDT) method is presented in this paper. In TDDT, both dispersion removal and signal waveform correction are accomplished to result in more convenience of dispersive signal interpretation. Instead of the complex back-propagation concept, only the basic Fourier transform (FT) properties are used to study the principle of TDDT. The realization of TDDT under broadband excitation and narrowband excitation is discussed, in which the signal waveform maintenance is of particular interest and the reason for TDDM disturbance of the signal waveforms is also investigated. Numerical simulations on A0 or S0 mode signals are implemented for the primary validation of TDDT. Then, in association with the traditional delay-and-sum algorithm, a high spatial resolution imaging method based on TDDT is developed. An experimental study is finally arranged to demonstrate the efficiency of TDDT and the TDDT-based imaging method.
Time-optimal quantum computation

Given any quantum error correcting code permitting universal fault-tolerant quantum computation and transversal measurement of logical X and Z, we describe how to perform time-optimal quantum computation, meaning the execution of an arbitrary Clifford circuit followed by a layer of independent T gates and any necessary feedforward measurement determined corrective S gates all in the time of a single physical measurement. We assume fast classical processing and classical communication, and argue the reasonableness of this assumption. This enables fault-tolerant quantum computation to be performed orders of magnitude faster than previously thought possible, with the execution time independent of the error correction strength.
Robust, Gain-Scheduled Control of Wind Turbines

The control of wind turbines is a very challenging task becau se it requires multi-objective control that needs to take into account effects like structu ral fatigue, power production/quality, and slip in the generator. In this thesis, a nu mber of linear parameter varying (LPV) design methods are investigated for use with medium to large scale systems and a method has been found to provide a numerically reliable comp utation of the controller. The thesis begins with an introduction to the control of wind turbines and provides an overview of the different methods that have been applied. Th is introduction is followed by a general introduction to LPV systems and the base for the a vailable design methods. The application of the LPV framework to the control of nonlin ear systems requires a method for describing the system by a LPV model. For doing th is there are two main directions: Jacobian-based linearisation or quasi-LPV mo dels through a substitution of nonlinearities by parameters. In the latter method the sche duling parameter is a function of the state vector which can introduce conservatism. This i ssue is investigated in the thesis leading to a proposed procedure with focus on frozen p arameter dynamics. The numerics in the design algorithms is one of the key issues for getting the methods working for medium to large scale systems. For the associate d optimisation problem, a grid-based method has been found promising and it has been fo und that the choice of state space realisation plays a very important role and a sim ulation based method has been developed for choosing a proper realisation for contro ller design. For closed loop analysis a Gramian-based method has been found promising. The construction of the LPV controller can be very challengi ng from a numerical point of view. Several algorithms have been investigated an d a method based on a classical result fromH∞ control has been found superior from a numerical point of vie w. This method does not directly produce a parameterised contr oller and another method (which can calculate a parameterised controller) has been m odified to enhance numerical performance. The numerical performance of this modifie controller is still not as strong as the first method, which makes the choice of construc tion algorithm a trade-off between numerical performance and calculating a parameter is d controller. A graphical design tool has been developed on the basis of the numerical findings for conditioning of algorithms for the design of LPV control lers. This tool provides an easy user interface which makes it possible for non-experts to design LPV controllers without worrying about matrix inequalities, construction algorithms, etc. The designer only needs to enter the model, weighting functions, tolerat ed rate of variation and basis functions for the storage (Lyapunov) functions. Then the co ntroller can be designed automatically by pressing a few buttons. Large scale design problems can be very difficult to solve fro m a numerical point of view. For these systems the tool provides a number of numeric al tuning handles with
A Survey of Immersive Systems for Shape Manipulation

Immersive modelling systems have predominantly used non-natural interfaces and devices for shape modification. The new technologies for gesture and speech interaction can provide more familiar interface and reduce the cognitive complexity of current user interfaces of traditional visualization and modelling systems, making it possible manipulating and modifying the shape in a simple and effective manner even by non-expert users. In this paper, we present a survey of existing approaches for immersive shape modelling and manipulation. Current approaches are analyzed according to three characterizing key aspects: input method, supported operations and type of representation of the shape. Finally, the paper briefly introduces our current approach to verify the existence of consistency in hand motions/gestures among different users for 3D modelling tasks in virtual environment, as a first step for the creation of natural interfaces in immersive shape manipulation.
The uncertainty of experimental derivatives: application to strain measurement

A procedure is presented to evaluate the uncertainty of derivatives computed from polynomial curves or surfaces fitted to experimental data. The procedure takes into account the uncertainties in the dependent and independent variables and agrees with international recommendations. It is valid independent of the experimental technique from which data are obtained. The application of the procedure is demonstrated by evaluating the uncertainty of strains calculated by differentiation of whole-field displacement data obtained by moiré interferometry.
Resonant heteroclinic cycles and singular hyperbolic attractors in models for skewed varicose instability

We consider a system of differential equations proposed by Busse et al (1992 Physica D 61 94–105) to describe the development of spatio-temporal structures in Rayleigh–Bénard convection, near the skewed varicose instability. Numerical computations make it clear that the global bifurcations are organized by a codimension two bifurcation with heteroclinic cycles and a double principal stable eigenvalue at the origin. We carry out the bifurcation study and prove in particular the occurrence in the unfolding of robustly transitive strange attractors akin to Lorenz attractors. In contrast to the actual Lorenz attractors, these attractors contain two equilibria.