Miracle-dz/UniFAR-FTUs huggingface dataset:
Computation of Fan Noise Radiation through an Engine Exhaust Geometry with Flow

This paper outlines a computational model of noise radiation from a realistic engine exhaust geometry with flow. The computational model described allows acoustic waves, propagating inside the bypass duct of a generic aircraft engine, to be admitted into a computational domain that includes the aft duct section, the exit plane of the duct, and the jet flow immediately downstream. The method has three parts: a matching process to admit acoustic waves into the induct propagation region; near field propagation inside the duct and diffraction at the lip of the exhaust duct; and an integral surface for far field directivity. In this model the near field propagation is determined by a numerical solution of a 2.5D form of the linearised Euler equations. The mean flow about which the equations are linearised is assumed to be axisymmetric. The proposed method is illustrated through a case study on the radiation of a typical fan assembly generated acoustic wave from a generic engine bypass duct. Inside the duct, an acoustic wave of circumferential order m = −13 and comprising five radial modes (n = 1 – 5) is admitted into the model as inputs on the boundary of the computation domain. The radiation of the acoustic wave through the exhaust geometry and mean flow is determined, with the effect of acoustic treatment through the inclusion of lined duct sections also examined.
An Accurate Asymptotic Approximation for Experience Rated Premiums

In the Bayesian approach, the experience rated premium is the value which minimizes an expected loss with respect to a posterior distribution. The posterior distribution is conditioned on the claim experience of the risk insured, represented by a n-tuple of observations. An exact analytical calculation for the experience rated premium is possible under restrictive circumstances only, regarding the prior distribution, the likelihood function, and the loss function. In this article we provide an analytical asymptotic approximation as n → ∞ for the experience rated premium. This approximation can be obtained under more general circumstances, it is simple to compute, and it inherits the good accuracy of the Laplace approximation on which it is based. In contrast with numerical methods, this approximation allows for analytical interpretations. When exact calculations are possible, some analytical comparisons confirm the good accuracy of this approximation, which can even lead to the exact experience rated premium.
Active plasmonic and metamaterials and devices

This communication focuses on the integration of organic nonlinear optical and gain materials into plasmonic and metamaterial device architectures and most specifically focuses on the integration of organic electro-optic (OEO) materials into such structures. The central focus is on structures that lead to sub-optical wavelength concentration of light (mode confinement) and the interaction of photonic and plasmonic modes. Optical loss and bandwidth limitations are serious issues with such structures and optical loss is evaluated for prototype device architectures associated with the use of silver and gold nanoparticles and membranes supporting plasmonic resonances. Electro-optic activity in organic materials requires that chromophores exhibit finite noncentrosymmetric organization. Because of material conductivity and integration issues, plasmonic and metamaterial device architectures are more challenging than conventional triple stack all-organic device architectures and electro-optic of a given OEO material may be an order of magnitude less in such structures. Because of this, we have turned to a variety of materials processing options for such integration including crystal growth, sequential synthesis/self assembly, and electric field poling of materials deposited from solution or by vapor deposition. Recent demonstration of integration of silicon photonic modulator and lithium niobate modulator structures with metallic plasmonic structures represent a severe challenge for organic electro-optic material plasmonic devices as these devices afford high bandwidth operation and attractive VμL performance. Optical loss remains a challenge for all structures.
Coloration Modeling and Processing of Commodity Plastic Buttons in Supercritical Carbon Dioxide

We examined the color processing of the commodity plastic buttons made of acrylic, polyester, nylon, and casein with scCO2. The buttons’ dyeing color depth (K/S) was measured over a wide range of scCO2 and correlated accurately with the response surface method. Moreover, we measured the solubility of C.I. Disperse Red 22 in scCO2 to formulate a dye-sorption model for the K/S value in the color processing of the plastic buttons. Finally, the dye-sorption model for the K/S value combining the dye solubility in scCO2 with the dye diffusion inside the buttons successfully represented the color processing of the buttons.
Influence of heating temperature on structural properties of sol-gel materials

In this paper, the influence of heating temperature on the properties of sol-gel materials was investigated . The aim of the study was to examine the production repeatability. All samples were made with factor R = 15, denoting the ratio of the number of precursor (TEOS) moles to solvent (water) moles. The samples were prepared in acid hydrolysis route on water, whereas two groups were considered: in one group the hydrolysis was terminated by addition of NH3·H2O and in the other there was no addition of base. The samples were stored for 1 month at room temperature and then exposed to high temperatures: 1000, 1200 and 1350°C. They were examined by means of scanning electron microscopy (SEM). The electron microphotographs were recorded, digitized and analyzed. The Fisher linear discriminant analysis for evaluation of the microscopic images was exploited. It was shown that the repeatability varied between 83.24% and 95.48%. The analysis demonstrated that the best results were achieved for neutralized samples made at 1000°C.
Influence of surface coverage on the effective optical properties of porous silicon modeled as a Si-wire array

The effective dielectric function, effective absorption coefficient and effective refractive index for a model of porous silicon (PS) are calculated using the volume and surface averaging method. The model consists of periodic Si wires with different surface coverages. This approach allows to obtain analytical results within certain approximations. The method uses experimental parameters to characterize the bulk and the surface. We choose the bulk c-Si, and cover it with three different possible surface skins: siloxanes, a-Si:H and SiO2. The results are compared with PS experimental data and other theoretical approaches for silicon wires. We obtain good agreement for certain coatings. Our results emphasize the important role of surface coatings in the effective response of porous silicon.
One-Shot Bargaining Mechanisms

We consider the situation that two players have cardinal preferences over a finite set of alternatives. These preferences are common knowledge to the players, and they engage in bargaining to choose an alternative. In this they are assisted by an arbitrator (a mechanism) who does not know the preferences. Our main positive result suggests a satisfactory-alternatives mechanism wherein each player reports a set of alternatives. If the sets intersect, then the mechanism chooses an alternative from the intersection uniformly at random. If the sets are disjoint, then the mechanism chooses an alternative from the union uniformly at random. We show that a close variant of this mechanism succeeds in selecting Pareto efficient alternatives only, as pure Nash equilibria outcomes. Then we characterize the possible and the impossible with respect to the classical bargaining axioms. Namely, we characterize the subsets of axioms can be satisfied simultaneously by the set of pure Nash equilibria outcomes of a mechanism. We provide a complete answer to this question for all subsets of axioms. In all cases that the answer is positive, we present a simple and intuitive mechanism which achieves this goal. The satisfactory-alternatives mechanism constitutes a positive answer to one of these possibility cases (arguably the most interesting case). Our negative results exclude the possibility of an efficient mechanism with unique equilibrium outcome, and exclude the possibility of an efficient symmetric mechanism which is invariant with respect to repetition of alternatives.
Hierarchical Ordering of Schematic Knowledge Relating to Area-of-Rectangle Problems.

Schematic knowledge was assessed by asking 195 9th- and 10th-grade students to classify area-of-rectangle problems in terms of whether the text of each problem provided insufficient, sufficient, or irrelevant information for solution. Problems involving adjacent sides information were most accurately classified, followed in increasing order of difficulty by problems involving one side and the ratio of sides, one side and the perimeter, and one side and the diagonal. Students rarely demonstrated awareness of the structure of a more difficult problem after having failed on classification of a less difficult problem. When confronted with a problem for which they lacked the relevant schema, students often attempted to meet task requirements by inappropriately using a lower order template
Improvement of residents’ happiness index in tourism destinations based on guiding significance and tourism development

ABSTRACT Tourism has been widely recognized as a powerful tool for economic growth in rural communities around the world. The growth of rural tourism has always been a significant start in targeting poverty alleviation and promoting economic change in rural China. Rural tourism development is the participation of rural people in tourism and full integration into tourism development. Rural tourism development depends on the participation and support of rural residents. Therefore, this research explores the influencing factors of rural tourism residents’ happiness and their influence on tourism support. The sample was selected from Anren Town, Chengdu City, China, and the research subjects were residents of Anren Town. In this study, data were collected from 370 residents of Anren Town via a questionnaire survey. The results show that Community Involvement (CI) and Community Attachment (CA) positively affect residents’ Authentic Happiness (AH). This research found that improving residents’ support for tourism development can promote the development of rural tourism. The study finding provides a new perspective for the treatment of residents’ problems in tourism development and has guiding significance for the improvement of residents’ happiness index in tourism destinations. If the community is better, the happiness of the residents will be stronger.
Quantile dependence of Bitcoin with clean and renewable energy stocks: new global evidence

ABSTRACT This paper examines the time-varying spillover effects and connectedness of the Bitcoin price with clean and renewable energy stocks using the quantile VAR framework. We use daily price indices spanning from 1 January 2014, to 18 October 2022. Before probing the quantile spillover effects between the markets examined, we first examine the mean-based averaged connectedness. These results indicate that Bitcoin receives more shocks from markets in the system than it transmits. Additionally, Bitcoin emerges as a net receiver of return shocks with index evolution among the markets examined, driven mainly by own shocks. Shifting to the results obtained using the QVAR approach, evidence reveals that Bitcoin acts as a net recipient of shocks under different quantiles in the system. In addition, Bitcoin returns strongly correlate with renewable energy stock returns under extreme events. We also confirm the dominance of renewable energy markets over Bitcoin and that the magnitude of their connectedness is time and event dependent. These findings confirm the diversification potential and safe-haven properties of Bitcoin for portfolio investors.
Long-term stability of a quasiperiodic Ta/Al multilayer: Disintegration at room temperature analyzed by grazing angle x-ray scattering and photoelectron spectroscopy

A three-component Fibonacci (3CF) Ta/Al multilayer has been reinvestigated by specular and diffuse x-ray reflectivity and x-ray photoelectron spectroscopy (XPS) after 41 months of storage at room temperature. The specular reflectivity shows drastically suppressed diffraction peaks, whose positions and intensities are explained by severe interdiffusion of the Ta/Al bilayers building the 3CF sequence. Nonspecular reflectivity scans still indicate a high degree of interfacial roughness correlation in the growth direction that is attributed to the long spatial Fourier components of the interface profiles, which are substantially less affected by interdiffusion. The angle-resolved XPS spectra show that the Ta capping layer is completely oxidized and interdiffused by Al, whereas below the oxide layer Ta and Al coexist in metallic form in the same film. Both x-ray reflectivity and XPS yield an oxide layer of ∼30 A thickness. Despite the severe structural disintegration, the multilayer diffraction spectrum can st.
Simultaneous Trapping and Manipulation of Micro-Specimens Using an All-Dielectric One-Dimensional Photonic Crystal

We demonstrate a platform where optical evanescent vortex has been realized by focusing a laser beam with orbital angular momentum (OAM) onto an all-dielectric one-dimensional photonic crystal (1DPC). This platform can simultaneously trap and manipulate various micro-scale specimens (i.e., polymer microsphere, inorganic microwire, yeast cells and Escherichia coli cells). The working principle lies in the low loss of the excited Bloch surface waves (BSWs) that propagate on the dielectric 1DPC and form a virtual probe for trapping the specimens. The OAM encoded by the BSWs will then simultaneously manipulate the specimens, such as inducing the rotation or orbital motion. Both experimental and simulation results verify that the capability of this new platform is due to the two kinds of optical force induced by the BSWs, which presents a different mechanism from that by the commonly optical electric-field vortex. Optical trapping or manipulation of micro & nano specimens play important roles in physics, life and materials sciences, thus, this new platform will find applications in microscale assembly, cell-cell interaction, bioprinting and biosensing research, and also expand our understanding of the physics interaction between vector beam and BSWs.
A nuanced look into youth journeys of gender transition and detransition

Some media have suggested that many youths who have previously completed a gender transition are “ detransitioning ” . Their experience is often framed around the idea of regrets but rare are the articles that provide a nuanced examination of their journey. This article presents the perspectives of youths who have detransitioned or discontinued a transition regarding their experiences and feelings on their journey from transition to detransition. Semi-structured interviews were conducted with 20 youths between the age of 16 and 25 years who were recruited on social media and who transitioned and detransitioned or discontinued their transition. Data were analysed according to thematic analysis. Regrets and feelings of satisfaction can both coexist. The processes of transition and discontinuation or detransition appear to be non-linear and participants do not necessarily return to a cisgender identity. Ambiguous loss theory is applied to frame youth experiences and feelings and to suggest way forward for intervention
Stellar evolution models at the Magellanic Cloud metallicities

Abstract The Magellanic Clouds are great laboratories to study the evolution of stars at two metallicities lower than solar. They provide excellent testbeds for stellar evolution theory and in particular for the impact of metallicity on stellar evolution. It is important to test stellar evolution models at metallicities lower than solar in order to use the models to predict the evolution and properties of the first stars. In these proceedings, after recalling the effects of metallicity, we present stellar evolution models including the effects of rotation at the Magellanic Clouds metallicities. We then compare the models to various observations (ratios of sub-groups of massive stars and supernovae, nitrogen surface enrichment and gamma-ray bursts) and show that the models including the effects of rotation reproduce most of the observational constraints.
Stress analysis in continuous media with an edge dislocation by finite element dislocation model

In this paper, a finite element dislocation model is proposed, based on well‐known mathematical dislocation model. As application examples, the stress distributions around an edge dislocation in infinite homogeneous and inhomogeneous regions are calculated and compared with the analytical results. The FEM results coincide well with the exact solutions. The results show an applicability and a usefulness of finite element dislocation model, and further, a possibility of analysing a dislocation problem in finite region with complicated shapes and boundary conditions. Copyright © 2002 John Wiley & Sons, Ltd.
The Impact of Continued Watching English Movie Series on Students’ English Capability (Case Study: Peaky Blinder and Friends)

This study investigates the impact of watching the English-language series of Peaky Blinders and Friends towards the improvement language ability in terms of word pronunciation, long-sentence listening, and grammatical analysis. This point outs the impact of continued exposure to English media to improve the student’s capability of learning English. The study has been arranged for 3 months by involving high school students from SMA 999 in Jakarta with a total sample of 25 students. The data were then gathered through conventional paper-based testing for Listening and grammar proficiency which encapsulated into Reading and Writing section. Speaking assessment was conducted through an interview. The tests were conducted in three main stages, the pre- test, mid-tests and post-test. The mid-tests were held after the first 2 week of the month. The result of the study showed that there were notable improvements in the English skills among 25 students, particularly in the Listening aspects as shown by one-way ANOVA and Tukey HSD analysis. However, the data from other aspects such as Reading, Writing and Speaking despite showed an upward trend, did not produce improvement as significant as Listening aspects. This phenomenon might be caused by the lack of students’ knowledge foundation regarding several language aspects therefore most students require longer time to completely improve their ability. From this point, this study can suggest that using movie series could be a great tool for English education to improve the students’ awareness of English and therefore would naturally improve their English.
Will Chinese students stop coming to the UK? A push–pull analysis among Chinese graduates from UK’s taught master’s programs 20 years apart

ABSTRACT China is a major source country of students in the UK’s taught Master’s programs. The reliance on China as a major source country has caused some concerns over its sustainability. Will the Chinese students continue to come? To answer this question, a push–pull factor analysis is conducted on the perceptions of Chinese students who graduated from the UK around the year 2000 and 2020. The goal is to explore the major pull factors for Chinese students’ mobility to the UK and whether there have been changes in the past 20 years. The findings of this pseudo longitudinal study suggest that, though most of the UK’s pull factors have stayed stable, the declining weight of the UK’s higher education reputation should be concerning. To sustain the UK’s attractiveness, the UK universities should slow the neoliberal expansion of international recruitment and strengthen the desirable Socratic approach to teaching and learning.
Improvement on the numerical dispersion of 2-D ADI-FDTD with artificial anisotropy

In this letter, by introducing artificial anisotropy into computational space, a simple and efficient approach to reduce numerical dispersion of the two-dimensional alternating direction implicit finite-difference time-domain (ADI-FDTD) method is proposed. It is shown that performance of the ADI-FDTD method can be improved significantly for both single frequency simulations and relatively wideband problems. Consequently, the usefulness and effectiveness of the ADI-FDTD method can be notably enhanced.
Capacitevely loaded bowtie antenna for ultrawideband impulse radio

The impact of an azimuthal slot in the antenna flair on the performance of a bowtie antenna has been analyzed. It has been shown that the slot is equivalent to resistance‐capacitance loading. The resistance of the slot is physically caused by radiation of electromagnetic energy from the slot. Equivalent resistance and capacitance of the slot have been analyzed against geometrical parameters and frequency. The azimuthal slot has been used to improve the bowtie performance and to optimize this antenna for an ultrawideband impulse radio system under development. After optimization, the antenna exhibits a better performance than the conventional bowtie in terms of efficiency, late‐time ringing, and matching to the generator/receiver. The performance of the optimized antenna has been verified experimentally; good agreement between theory and experiment has been observed.
Association of Metabolically Healthy Obesity and Risk of Cardiovascular Disease Among Adults in China: A Retrospective Cohort Study

Purpose Previous studies have shown that metabolically healthy obesity (MHO) and changes in its status are connected to an increased incidence of cardiovascular disease (CVD). Yet, fewer studies have been conducted in China, especially for the middle-aged and elderly population, a high-risk group. The purpose of the study was to investigate the association between metabolic health status and CVD events. Patients and Methods A total of 46,055 participants were categorized into 6 subgroups with different metabolic states according to the existence of metabolic syndrome and body mass index (BMI). The changes in obesity and metabolic health status were defined from baseline to follow-up outcomes with a combination of overweight and obesity. Cox proportional hazards models estimated the association of CVD events and each BMI–metabolic groups. Results MHO and metabolic abnormality normal weight (MANW) subjects had a higher HR of CVD, 1.62 (95% CI, 1.36–1.92) and 1.24 (95% CI, 1.07–1.44), respectively, than their metabolically healthy normal weight (MHNW) counterparts. Then, more than 50% and 30% of the metabolically healthy overweight or obesity (MHOO) populations maintained their status and converted to a metabolically unhealthy state, respectively. Stable MANW, MHOO and metabolically abnormal obesity (MAO) were associated with a higher risk for CVD, 1.68 (95% CI, 1.37–2.05),1.26 (95% CI, 1.08–1.47) and 1.65 (95% CI, 1.45–1.88), respectively, than stable MHNW. Conclusion Despite being of normal weight, MANW status is in fact a risk factor for CVD, as well as MHO, especially for the Chinese middle-aged and elderly population. Furthermore, metabolic health is a transient state for partial middle-aged and elderly Chinese individuals, and MAO has the highest risk of CVD, including coronary heart disease (CHD) and stroke.