Miracle-dz/UniFAR-FTUs huggingface dataset:
INHERENT COMMITMENT TO SUSTAINABILITY AMONG BASQUE ADVENTURE TOURISM ENTERPRISES DESPITE CRISIS

Existing literature in the field of sustainable tourism highlights a number of barriers that impede the implementation of practices in this area. However, few studies have addressed the case of adventure tourism. Adopting a case study approach, this paper discusses a number of drivers of success identified by adventure tourism enterprise owners in Basque Country to contribute to the implementation of sustainable tourism practices. Adventure tourism has important social, economic, and environmental impacts on sustainability. The study focuses on learning how sustainable practices have changed in these companies because of the COVID-19 crisis. La literatura existente en el campo del turismo sostenible destaca una serie de barreras que dificultan la implementación de prácticas sostenibles en esta área. Sin embargo, encontramos escasos estudios que se centren en el caso del turismo activo. A través de un estudio de caso, este trabajo analiza un número de impulsores o facilitadores de éxito, identificados por los propietarios de empresas de turismo activo en el País Vasco, que contribuyen a la implementación de prácticas sostenibles. El turismo activo tiene importantes impactos en la sostenibilidad económica, social y medioambiental. El estudio se centra en conocer cómo han cambiado las prácticas sostenibles en estas empresas debido a una crisis como la del COVID-19.
Joint RIS Grouping Design Assisted Generalized Quadrature Reflection Modulation

In this paper, a novel joint reconfigurable intelligent surface (RIS) grouping design assisted generalized quadrature reflection modulation (JGD-GQRM) scheme is proposed for a single radio frequency (RF) multiple-input multiple-output (MIMO) system. In JGD-GQRM, a limited number of RIS elements are spatially grouped, and the remaining reflection patterns are utilized for joint mapping to improve the reliability of the transmission. Moreover, it maps additional information bits by full reflection passive beamforming to improve the system's spectral efficiency (SE). In addition to the optimal maximum likelihood (ML) detector that has high computational complexity, a low-complexity sequential greedy detection (SGD) for JGD-GQRM is proposed. Simulation results show that the proposed scheme can achieve better bit error rate (BER) performance than the existing reflection modulation.
A note on acceptance rate criteria for CLTS for Metropolis–Hastings algorithms

This paper considers positive recurrent Markov chains where the probability of remaining in the current state is arbitrarily close to 1. Specifically, conditions are given which ensure the non-existence of central limit theorems for ergodic averages of functionals of the chain. The results are motivated by applications for Metropolis–Hastings algorithms which are constructed in terms of a rejection probability (where a rejection involves remaining at the current state). Two examples for commonly used algorithms are given, for the independence sampler and the Metropolis-adjusted Langevin algorithm. The examples are rather specialized, although, in both cases, the problems which arise are typical of problems commonly occurring for the particular algorithm being used.
Empirical measures for incomplete data with applications

Methods are proposed to construct empirical measures when there are missing terms among the components of a random vector. Fur- thermore, Vapnik-Chevonenkis type exponential bounds are obtained on the uniform deviations of these estimators, from the true probabilities. These results can then be used to deal with classical problems such as statistical classification, via empirical risk minimization, when there are missing covariates among the data. Another application involves the uni- form estimation of a distribution function. AMS 2000 subject classifications: Primary 60G50, 62G15; secondary 62H30.
Optical PCB inspection system based on Hausdorff distance

In this paper, we propose a coarse-to-fine image comparison algorithm based on Hausdorff distance for PCB inspection. The Hausdorff distance can be used in a geometrics-based inspection framework for comparing binary edge maps extracted from the inspection images. To use the Hausdorff distance for image alignment, we need to compute the edge map from the input image as the first step. In some cases, one may use directed Hausdorff distance as a similarity measure in order to reduce the computational cost during the image alignment. Moreover, a modified version of directed Hausdorff distance is employed to enforce robustness against random noises introduced by edge detection. The search for the optimal alignment by minimizing the associated Hausdorff distance is accomplished by an efficient multi-resolutional downhill simplex search algorithm. In addition to the image alignment, we also apply a modified Hausdorff distance to detect defects in PCB. In our inspection system, we apply the partial Hausdorff distance in a local circuit window to reduce the inspection area dramatically, thus making it very efficient for PCB inspection. Experimental results on some PCB inspection examples are shown to demonstrate the accuracy and efficiency of the proposed Hausdorff-distance based inspection system.
Statistical Methods for the Mover-Stayer Model

Abstract The mover-stayer model, a generalization of the Markov chain model, assumes that there are two types of individuals in the population under consideration: (a) the “stayer,” who with probability one remains in the same category during the entire period of study; (b) the “mover,” whose changes in category over time can be described by a Markov chain with constant transition probability matrix. The transition probability matrix for movers, and the proportion of stayers among the individuals in each category at, say, the initial point in time, are unknown parameters. Various estimators of these parameters are presented herein, and the accuracy of these estimators is compared. We show, for example, that the estimators of these parameters used by Blumen, Kogan, and McCarthy [3] are not consistent estimators, while the estimators recommended herein are. In addition, tests of several hypotheses concerning the mover-stayer model are presented herein. The methods developed in this paper can be applied to t.
Research on the Use of Silicon-Ethanol Composite in Actuators

Silicon-ethanol is a relatively new smart composite in the category of phase-change materials (PCM). It consists of liquid ethanol entrapped in bubbles spread into a silicone rubber matrix, i.e., during cooling. The composite is able to expand significantly when heat is applied and shrink when it is removed. The properties of this material can be used in a new type of actuator. In this paper, the basic equations that describe the properties of actuators with a silicon-ethanol composite are given. Using them, two solutions of unidirectional actuators with a composite inserted into polycarbonate tubes and metal bellows are designed and investigated. In the study, actuators with different geometric dimensions and applied composite volumes are investigated. The elongations of the actuators and the blocking forces are measured. The theoretical relationships given at the beginning of the paper that describe the properties of the composite are validated using the performed experimental results of the built actuators. The tube actuators achieved elongation between 32% and 35% at a temperature of 75 degrees Celsius, that is, less than that predicted according to equations from earlier publications. Due to this, a modified equation that includes the influence of friction was proposed and compared with experimental results. The performance of the tube actuator deteriorates rapidly. In the case of bellow actuators, they stabilize after a few cycles of heating and cooling.
Design of tunable wavelength selector with fiber Bragg gratings with cladding made of Electro-optic materials

A new tunable wavelength selector based on the fiber Bragg grating with cladding made of LiNbO3 with optical axis running along the axis of fiber Bragg grating was investigated. The calculated results indicate that the reflected wavelength can be tunable from 1550.921 nm to 1548.9668 nm with variation of electric field running along the fiber axis from 107 to 108V/m, the reflectivity varies from 99.8252% to 99.9715%. The tunable wavelength range will be large with the electric field increases. These rules indicate that the new tunable wavelength selector based on the fiber Bragg grating with cladding which is made of uniaxial anisotropic electro-optic crystal material can be achieved through adjusting the electric field intensity while keeping the fiber grating length, periodicity and the other parameters as constants.
On the equivalent systems for concurrent springs and dampers – Part 2: Small out-of-plane oscillations

Concurrent linear springs belonging to systems that perform small out-of-plane oscillations around a stable equilibrium position are considered with a view to obtaining equivalent systems of three mutually orthogonal linear springs. Theorems defining their stiffness coefficients as well as their position, i.e. the position of the principal stiffness axes for which the potential energy does not contain mixed terms, are stated and proven. So far unknown invariants related to the sum of original and new stiffness coefficients are provided. In addition, the equivalent system of three mutually orthogonal dampers is obtained for any system of out-of-plane concurrent linear viscous. The theorem defining their damping coefficients and their directions, collinear with the principal damping axes for which the dissipative function does not contain mixed terms, is provided. The corresponding invariant for damping coefficients is presented, too. An ellipsoid of displacement and an ellipsoid of stiffness are discussed. Three illustrated examples are given.
Grain shape effects on dielectric and electrical properties of rocks

Recently there has been a considerable interest in the effect of anisotropy in the grain shape in the electrical and dielectrical properties of rocks and other inhomogeneous media (Sen 1981a, b; Sen et al, 1981; Mendelson and Cohen, 1982; and Kenyon, 1983). In this note I point out that equation (34) of Mendelson and Cohen (MC) is incorrect. The dc limit of MC equation (34) for the conductivity of rock σ, in terms of porosity ϕ and water conductivity σw, gives lnϕ=mˆ-1lnσσw, or σ=σwϕmˆ, where mˆ-1=〈1+2(1-3L)2(5-3L)(1+3L)-3L(1-L)1+3L〉. L is the depolarization factor along the principal axis of spheroidal grain and 〈 〉 denotes an average over the distribution in L. This value of mˆ is in disagreement with the correct value of m in equation (28) of MC [equation (6) below]. [When the sign mistakes in equations MC (33)–(34) are corrected, mˆ=〈3(1-L2)/(5-3L)〉-1. This agrees with equation (6) below for the case when L has a single value and averaging is redundant. ] This inconsistency arises from an incorrect rep.
AN INVESTIGATION OF PHOTOELECTRIC RADIAL-VELOCITY SPECTROMETERS AS USED IN THE ANALYSIS OF CEPHEID VARIABLES.

The authors have used synthetic stellar spectra to simulate observations of Cepheid variables with photoelectric radial-velocity spectrometers. They have found that the projection factor used to convert radial velocities to pulsation velocities depends on stellar temperature, overall stellar radial velocity, and pulsational velocity, as well as the method used to determine the radial velocity from the cross-correlation dip. The shape of the cross-correlation dip has been found to vary with the pulsation velocity and with the parameters of the stellar models.
Mitigation of exploding-wire-generated blast-waves by aqueous foam

In this work, we implement an exploding wire technique to generate small-scale cylindrical blast waves in aqueous foam. The exploding wire system offers an easy to operate and effective tool for studying blast-wave/foam interaction related phenomena in real explosion scenarios. The mitigation of blast waves as a function of the thickness of the foam barrier is discussed and quantified. A fluid mixture pseudo-gas based numerical approach with the aid of the point explosion theory is used to separate the mitigation mechanisms into the near- and the far-field related groups and to analyze the contribution of each group to the overall losses of the blast wave energy.
QoS-Aware Joint Task Scheduling and Resource Allocation in Vehicular Edge Computing

Vehicular edge computing (VEC) has emerged in the Internet of Vehicles (IoV) as a new paradigm that offloads computation tasks to Road Side Units (RSU), aiming to thereby reduce the processing delay and resource consumption of vehicles. Ideal computation offloading policies for VEC are expected to achieve both low latency and low energy consumption. Although existing works have made great contributions, they rarely consider the coordination of multiple RSUs and the individual Quality of Service (QoS) requirements of different applications, resulting in suboptimal offloading policies. In this paper we present FEVEC, a Fast and Energy-efficient VEC framework, with the objective of realizing an optimal offloading strategy that minimizes both delay and energy consumption. FEVEC coordinates multiple RSUs and considers the application-specific QoS requirements. We formalize the computation offloading problem as a multi-objective optimization problem by jointly optimizing offloading decisions and resource allocation, which is a mixed-integer nonlinear programming (MINLP) problem and NP-hard. We propose MOV, a Multi-Objective computing offloading method for VEC. First, vehicle prejudgment is proposed to meet the requirements of different applications by considering the maximum tolerance delay related to the current vehicle speed. Second, an improved Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is adopted to obtain the Pareto-optimal solutions with low complexity. Finally, the optimal offloading strategy is selected for QoS maximization. Extensive evaluation results based on real and simulated vehicle trajectories verify that the average QoS value of MOV is improved by 20% compared with the state-of-the-art VEC mechanism.
First phytoplankton community assessment of the Kong Håkon VII Hav, Southern Ocean, during austral autumn

Abstract. We studied phytoplankton and protozooplankton community composition based on light microscopy, flow cytometry, and photosynthetic pigment data in the Atlantic sector of the Southern Ocean during March 2019 (early austral autumn). Sampling was focused on the area east of the prime meridian in the Kong Håkon VII Hav, including Astrid Ridge, Maud Rise, and a south–north transect at 6∘ E. Phytoplankton community composition throughout the studied area was characterized by oceanic diatoms typical of the iron-depleted high-nutrient, low-chlorophyll (HNLC) Southern Ocean. Topography and wind-driven iron supply likely sustained blooms dominated by the centric diatom Chaetoceros dichaeta at Maud Rise and at a station north of the 6∘ E transect. For the remainder of the 6∘ E transect, diatom composition was similar to the previously mentioned bloom stations, but flagellates dominated in abundance, suggesting a post-bloom situation and likely top-down control by krill on the bloom-forming diatoms. Among flagellates, species with haptophyte-type pigments were the dominating group. At Astrid Ridge, overall abundances were lower and pennate diatoms were more numerous than centric diatoms, but the community composition was nevertheless typical of HNLC areas. The observations described here show that C. dichaeta can form blooms beyond the background biomass level and also fuels both carbon export and upper trophic levels within HNLC areas. This study is the first thorough assessment of phytoplankton communities in this region and can be compared to other seasons in future studies.
Theories, Models, and Equations in Biology: The Heuristic Search for Emergent Simplifications in Neurobiology

This article considers claims that biology should seek general theories similar to those found in physics but argues for an alternative framework for biological theories as collections of prototypical interlevel models that can be extrapolated by analogy to different organisms. This position is exemplified in the development of the Hodgkin‐Huxley giant squid model for action potentials, which uses equations in specialized ways. This model is viewed as an “emergent unifier. ” Such unifiers, which require various simplifications, involve the types of heuristics discussed in Wimsatt’s writings on reduction, but with a twist. Here, the heuristics are used to generate emergent rather than reductive explanations.
Spatial Patterns for Discrete Models of Diffusion in Excitable Media

In a spatially homogeneous environment an excitable media is characterized by a globally stable equilibrium state, and also by a threshold mechanism which produces a large amplitude response to a sufficiently large stimulus. This response is temporary, however, and the system soon returns to its equilibrium configuration. Such media are to be distinguished from oscillatory ones; the latter support self-excited spatially homogeneous oscillations. In this paper we show how spatial inhomogeneities in an excitable media tend to organize themselves to produce spatial patterns which oscillate periodically in time.
Throughput Enhancement of Dynamic Full-Duplex Cellular System by Distributing Base Station Reception Function

In-band full-duplex (IBFD) is a promising technology for improving spectral efficiency beyond 5G and 6G. The dynamic duplex cellular (DDC) system has been proposed as a method for the phased introduction of IBFD into cellular systems while maintaining backward compatibility. Although previous studies have shown that DDC systems can improve the average user throughput, twice the spectral efficiency compared to half-duplex (HD), ideally expected for IBFD, has not been achieved. The main component that disturbs throughput enhancement is the residual component of self-interference (SI) at the base station (BS), which SI cancellers cannot entirely suppress. In this study, we propose a DDC system with a dedicated transmitter (DT) and multiple distributed receivers called remote receivers (RRs) for the BS to reduce the effective SI and enhance uplink reception quality. We implement user equipment scheduling and power control for the DDC system in the topology with DT and multiple RRs and improvement by IBFD. evaluate its performance using computer simulations in a single-cell environment. The proposed DDC system with receiver-distributed topology achieves up to 96% improvement in average user throughput of uplink and downlink from the HD system with the same topology, which is close to the ideal performance.
Microwave noise field: active radiometry principles and applications

Principles of Active Radiometry are presented. Noise radiators are used to generate the low-coherence microwave noise field, and radiometers to evaluate its intensity, polarization and coherence. Several types of noise radiators are described as well as radiometers and antennas. The following applications are introduced: Material evaluation where insertion loss and reflectivity of grainy, irregular and moving objects are preferable. Microwave Coherence Tomography allowing the depth irregularity to be detected in low-loss objects. Near-Field antenna testing, field coherence evaluation, and spatial combining of noise radiators.
Asymptotics of the multipositon–soliton τ function of the Korteweg–de Vries equation and the supertransparency

The asymptotics of the τ function generating the N‐positon–M‐soliton solution of the Korteweg–de Vries equation is calculated. This allows to prove that solitons do not experience any phase shift in a collision with positons. The positons themselves survive mutual collisions unchanged. This phenomenon is called the supertransparency or super‐reflectionless property of the multipositon solutions. The linear aspects of this phenomenon are also discussed. It is demonstrated that positons acquire two additional but always finite phase shifts in collision with solitons. This result admits a natural extension to any number of solitons and positons in interaction.
Recent advances in regenerative biomaterials

Abstract Nowadays, biomaterials have evolved from the inert supports or functional substitutes to the bioactive materials able to trigger or promote the regenerative potential of tissues. The interdisciplinary progress has broadened the definition of ‘biomaterials’, and a typical new insight is the concept of tissue induction biomaterials. The term ‘regenerative biomaterials’ and thus the contents of this article are relevant to yet beyond tissue induction biomaterials. This review summarizes the recent progress of medical materials including metals, ceramics, hydrogels, other polymers and bio-derived materials. As the application aspects are concerned, this article introduces regenerative biomaterials for bone and cartilage regeneration, cardiovascular repair, 3D bioprinting, wound healing and medical cosmetology. Cell-biomaterial interactions are highlighted. Since the global pandemic of coronavirus disease 2019, the review particularly mentions biomaterials for public health emergency. In the last section, perspectives are suggested: (i) creation of new materials is the source of innovation; (ii) modification of existing materials is an effective strategy for performance improvement; (iii) biomaterial degradation and tissue regeneration are required to be harmonious with each other; (iv) host responses can significantly influence the clinical outcomes; (v) the long-term outcomes should be paid more attention to; (vi) the noninvasive approaches for monitoring in vivo dynamic evolution are required to be developed; (vii) public health emergencies call for more research and development of biomaterials; and (viii) clinical translation needs to be pushed forward in a full-chain way. In the future, more new insights are expected to be shed into the brilliant field—regenerative biomaterials.
The Impact of Macroeconomics Factors on the Jakarta Composite Index

This study aims to assess the relationship between macroeconomics factors on the Jakarta Composite Index. The multiple linear regression is employed to examine the impact of four macroeconomics variables namely GDP growth, inflation, interest rate spread, and broad money (money supply) on the Jakarta Composite Index. The result presents that Jakarta Composite Index is negatively affected by inflation and interest rates, while the increase in money supply boost the Jakarta Composite Index. In this study GDP growth has no significant influence on the Jakarta Composite Index. Investors may take advantage of this circumstance, notably they can purchase blue chips when inflation and interest rates rise and sell their shares when the money supply is expanding.