Miracle-dz/UniFAR-FTUs huggingface dataset:
A Kind of Boundary-Layer 'Flutter': The Turbulent History of a Fluid Mechanical Instability

The transition from laminar to turbulent flow has been a notorious riddle in fluid dynamics since the nineteenth century. Hydrodynamic instabilities were regarded as a cause for the onset of turbulence, but their theoretical investigation led to paradoxical results. I focus on studies about the instability of laminar boundary-layer flow along a flat plate. The experimental discovery of boundary-layer oscillations (Tollmien-Schlichting waves) in the USA during World War II vindicated a long-disputed theory developed in Germany in the 1920s and 1930s. However, the instability which causes these oscillations marks only the initial phase of the onset of turbulence; higher-order instabilities had to be assumed in order to extend the analysis to the regions of the transition zone where more complex phenomena (such as "turbulent spots") mark the onset of turbulence. There is still no theory to describe these processes in a satisfactory manner. The emphasis on the fundamental character of the problem, however, tends to obscure the practical interests which motivated the study of boundary-layer instabilities throughout its long history. The disputed theories played a role in the quest for "laminar airfoils" and other practical applications. Theory and practice are entangled more intimately than it would appear from the rhetoric about the fundamental character of the "turbulence problem".
From the Henderson Poverty Inquiry to the Cashless Debit Card: Alternatives to the Reframing of Poverty as Welfare Dependency in Australia

The recent announcement of a Senate inquiry into the ‘extent and nature of poverty in Australia’ reminds us that poverty policy in Australia has long been a contested concept in terms of identification of causes and potential solutions. The 1972–1975 Henderson Commission of Inquiry into Poverty led by Ronald Henderson arguably represented the high point of Australian poverty research and policy discourse. That inquiry established a framework for measuring poverty based on a link to the minimum wage, and incorporating housing costs which has informed all subsequent research.
INDIVIDUAL DIFFERENCES IN MULTIDIMENSIONAL SCALING

Applications of Tucker and Messick's model of individual differences in multidimensional scaling have suggested the occasional appropriateness of a refinement of that model. The refinement is to consider just one multidimensional stimulus space for all persons (or sets of persons) and with each person having a “weight” for each axis. This paper presents a formal description of this model and a least squares solution for its parameters. The solution has yet to be tested empirically.
Exact solutions of the bound Dirac and Klein Gordon equations in non co propagating electromagnetic plane waves

A new class of exact solutions of the bound Dirac and bound Klein Gordon equations in non co propagating plane waves is found. The solutions are based on the physical principle of maintaining local gauge invariance in the Furry picture Lagrangian when N external fields can undergo independent gauge transformations. The solutions can be expressed in terms of the Hamilton Jacobi action and a gauge invariant effective particle momentum in the ensemble of external fields. Rotations of the effective particle momentum, which preserve local gauge invariance, are introduced into the action using matrix calculus. The set of such rotations provides the class of new solutions constituting a family of Volkov like solutions for one external field. When applied to two or more non co propagating external fields, the rotational symmetry provides counter terms which decouple the fields. The bound state equations of motion become solvable for any number of non co propagating external fields. Through angular spectral decomposition, which represents electromagnetic fields of any form as a spatial Fourier series of non co propagating plane waves, the new solutions described here can be applied to strong field physics problems in any external electromagnetic field.
Optical/Near-IR spatially resolved study of the H ii galaxy Tol 02

The main goal of this study is to characterise the stellar populations in very low metallicity galaxies. We have obtained broad U, B, R, I, J, H, K, intermediate Stromgren y and narrow H{\alpha} and [OIII] deep images of the Wolf-Rayet, Blue Compact Dwarf, H II galaxy Tol 02. We have analysed the low surface brightness component, the stellar cluster complexes and the H II regions. The stellar populations in the galaxy have been characterised by comparing the observed broad band colours with those of single stellar population models. The main results are consistent with Tol 02 being formed by a 1.5 Gyr old disk component at the centre of which a group of 8 massive $>10^4 \, M_{\odot}$ stellar cluster clumps is located. Six of these clumps are 10 Myr old and their near infrared colours suggest that their light is dominated by Red Supergiant stars, the other two are young Wolf-Rayet cluster candidates of ages 3 and 5 Myr respectively. 12 H II regions in the star-forming region of the galaxy are also identified. These are immersed in a diffuse H{\alpha} and [OIII] emission that spreads towards the North and South covering the old stellar disk. Our spatial-temporal analysis shows that star formation is more likely stochastic and simultaneous within short time scales. The mismatch between observations and models cannot be attributed alone to a mistreat of the RSG phase and still needs to be further investigated.
Settings in The 2019 Teenagers’ Historical Novels Competition “Wira Demokrasi” by Nor Azida Ishak

Historical novels are getting less popular these days due to its content of story on historical events. To which it does not interests a lot of readers. Most of the historical novel readers are mainly adults in their 30s up to the elderlies in the late 50s to 70s. Therefore, our youngsters are not that interested in reading historical novels as compared to other kinds of novels like romance, comedy and many others. For such reason, authors tend to change their perspective and started to write about historical novels for teenagers. The content and elaboration of the novel should be able to attract the interest of the youngsters in reading the historical novels. Thus, the objective of this study is to identify settings in the 2019 teenagers’ historical novels competition “Wira Demokrasi” by Nor Azida I shak. The samples of the study consisted of the “Wira Demokrasi” teenagers’ historical novel itself. The “Wira Demokrasi” teenagers’ historical novel were chosen from the 2019 teenagers’ historical novels competition and won the consolation price out of the 8 novels who competed in the competition. This study is a quantitative study whereby the number of settings that took place in the novel in each chapter were taken into account. The different settings used in each chapter of the novel were further elaborated into 3 different situations which are the place, time and society which were involved in each setting. The settings used in the novel were captured and analysed by using Discourse Analysis Theory by Normaliza Abd Rahim (2019; 2021). The result of the study showed that setting plays an important role in elaborating the detail of the storyline. It helps to identify the actual surrounding and environment that the character of the story had to go through or face during certain situation. It also helps the reader to understand more in depth of what is happening in the storyline which mainly focused on the place, time and society involved. It is hoped that further studies will focus on other important aspects that needs further elaboration in the teenagers’ h istorical novel.
MEDIA ROLE ON IPO SHARE RETURN DURING THE COVID-19 PANDEMIC

The Covid-19 pandemic has had an impact on various sectors, particularly in the financial sector. One of the triggers is the limitation of activities from the community so that it affects business activities which have an impact on the economy. The company's solution in seeking funds is to conduct an Initial Public Offering (IPO). Companies that conduct IPO have a high risk. This is because investors tend to choose to save their funds in savings, invest in gold and foreign currencies during the pandemic. Moreover, the role of the media today is closely related to the investor decisions. The purpose of this study is to analyze the role of the media on the considerations of investors in buying IPO shares and to analyze the requirement of company performance to conduct an IPO. This study uses a sample of 52 companies that conduct IPOs from March 2020 to May 2021. Secondary data collection uses company financial statements obtained through the IDX official website and Thomson Reuters. This study finds that the role of the media has a positive effect on investors' considerations in buying IPO shares and company size, profitability and leverage ratios are required for companies to conduct IPO.
Limit theorems and estimation theory for branching processes with an increasing random number of ancestors

This paper deals with a Bienaymé-Galton-Watson process having a random number of ancestors. Its asymptotic properties are studied when both the number of ancestors and the number of generations tend to infinity. This yields consistent and asymptotically normal estimators of the mean and the offspring distribution of the process. By exhibiting a connection with the BGW process with immigration, all results can be transported to the immigration case, under an appropriate sampling scheme. A key feature of independent interest is a new limit theorem for sums of a random number of random variables, which extends the Gnedenko and Fahim (1969) transfer theorem.
A new formulation of the Type Ia supernova rate and its consequences on galactic chemical evolution

In recent papers, Mannucci et al. and Mannucci, Della Valle & Panagia suggested, on the basis of observational arguments, that there is a bimodal distribution of delay times for the explosion of Type Ia supernovae (SNe). In particular, a percentage from 35 to 50 per cent of the total Type Ia SNe should be composed by systems with lifetimes as short as 10 8 yr, whereas the rest should arise from smaller mass progenitors with a much broader distribution of lifetimes. In this paper, we test this hypothesis in models of chemical evolution of galaxies of different morphological type: ellipticals, spirals and irregulars. We show that this proposed scenario is compatible also with the main chemical properties of galaxies. In this new formulation, we simply assume that Type Ia SNe are originating from C-O white dwarfs in binary systems without specifying if the progenitor model is the single-degenerate or the double-degenerate one or a mixture of both. In the framework of the single-degenerate model, such a bimodal distribution of the time delays could be explained if the binary systems with a unitary mass ratio are favoured in the mass range 5-8 M ⊙ , whereas for masses -2.0 dex, relative to the old models. For a typical elliptical of 10 11 M ⊙ of luminous mass, the new rate produces average [a/Fe] ratios in the dominant stellar population still in agreement with observations. The Type Ia SN rate also in this case shows an earlier peak and a subsequent faster decline relative to the previous results, but the differences are smaller than in the case of our Galaxy. We have also checked the effects of the new Type Ia SN rate on the evolution of the Fe content in the intracluster medium (ICM), as a consequence of its production from cluster ellipticals and we found that less Fe in the ICM is produced with the new rate, due to the higher fraction of Fe synthesized at early times and remaining locked into the stars in ellipticals. For dwarf irregular galaxies suffering few bursts of star formation, we obtain [O/Fe] ratios larger by 0.2 dex relative to the previous models.
Paradox of integration — Dynamics of two-dimensional status

According to Peter M. Blau (Exchange and Power in Social Life, Wiley and Sons, 1964, p. 43), the process of integration of a newly formed group has a paradoxical aspect: most attractive individuals are rejected because they raise fear of rejection. Often, their solution is to apply a self-deprecating strategy (SDS), which artificially raises the social statuses of their opponents. Here, we introduce a two-dimensional space of status, and we demonstrate that with this setup, the SDS can efficiently prevent the rejection. Examples of application of this strategy in the scale of a society are provided.
Figure Rotation of Cosmological Dark Matter Halos

We have analyzed galaxy- and group-sized dark matter halos formed in a high-resolution ΛCDM numerical N-body simulation in order to study the rotation of the triaxial figure, a property in principle independent of the angular momentum of the particles themselves. Such figure rotation may have observational consequences, such as triggering spiral structure in extended gas disks. The orientation of the major and minor axes are compared at five late snapshots of the simulation. Halos with significant substructure or that appear otherwise disturbed are excluded from the sample. We detect smooth figure rotation in 288 of the 317 halos in the sample. The pattern speeds follow a lognormal distribution centered at Ωp = 0.148 h km s-1 kpc-1 with a width of 0.83. These speeds are an order of magnitude smaller than required to explain the spiral structure of galaxies such as NGC 2915. The axis about which the figure rotates aligns very well with the halo minor axis in 85% of the halos and with the major axis in the remaining 15% of the halos. The figure rotation axis is usually reasonably well aligned with the angular momentum vector. The pattern speed is correlated with the halo spin parameter λ but shows no correlation with the halo mass. The halos with the highest pattern speeds show particularly strong alignment between their angular momentum vectors and their figure rotation axes. The figure rotation is coherent outside 0.12rvir. The measured pattern speed and degree of internal alignment of the figure rotation axis drops in the innermost region of the halo, which may be an artifact of the numerical force softening. The axis ratios show a weak tendency to become more spherical with time.
Escape of ionizing radiation from high-redshift dwarf galaxies: role of AGN feedback

While low mass, star forming galaxies are often considered as the primary driver of reionization, their actual contribution to the cosmic ultraviolet background is still uncertain, mostly because the escape fraction of ionizing photons is only poorly constrained. Theoretical studies have shown that efficient supernova feedback is a necessary condition to create paths through which ionizing radiation can escape into the intergalactic medium. We investigate the possibility that accreting supermassive black holes in early dwarf galaxies may provide additional feedback and enhance the leakage of ionizing radiation. We use a series of high resolution cosmological radiation hydrodynamics simulations where we isolate the different sources of feedback. We find that supernova feedback prevents the growth of the black hole, thus quenching its associated feedback. Even in cases where the black hole can grow, the structure of the interstellar medium is strongly dominated by supernova feedback. We conclude that, in the dwarf galaxy regime, supermassive black holes do not appear to play a significant role in enhancing the escape fraction and in contributing to the early UV background.
On Solutions of Forward‐Backward Stochastic Differential Equations with Poisson Jumps

Abstract In this paper, we use a purely probabilistic approach to study forward‐backward differential equations with Poisson jumps with stopping time as termination. Under some weak monotonicity conditions and Lipschitz conditions, the existence and uniqueness results of solutions are obtained, it may be served as the generalized results contrast to FBDE with Brownian motion. We also derive the convergence theorem of the solutions.
Constraints on the pre-impact orbits of Solar system giant impactors

We provide a fast method for computing constraints on impactor pre-impact orbits, applying this to the late giant impacts in the Solar System. These constraints can be used to make quick, broad comparisons of different collision scenarios, identifying some immediately as low-probability events, and narrowing the parameter space in which to target follow-up studies with expensive N-body simulations. We benchmark our parameter space predictions, finding good agreement with existing N-body studies for the Moon. We suggest that high-velocity impact scenarios in the inner Solar System, including all currently proposed single impact scenarios for the formation of Mercury, should be disfavoured. This leaves a multiple hit-and-run scenario as the most probable currently proposed for the formation of Mercury.
Environmental factors and stochasticity affect the fungal community structures in the water and sediments of Hulun Lake, China

Abstract Aquatic fungi form both morphologically and ecologically diverse communities. However, lake ecosystems are frequently overlooked as fungal habitats, despite the potentially important role of fungi in matter cycling and energy flow. Hulun Lake is a typical example of a seasonal glacial lake; however, previous studies have only focused on bacteria in this ecosystem. Therefore, in the current study, internal transcribed spacer ribosomal RNA (ITS rRNA) gene high‐throughput sequencing was used to investigate the fungal communities in paired water and sediment samples from the Hulun Lake Basin in China. A significant difference was found between the fungal communities of the two sample types. Across all samples, we identified nine phyla, 30 classes, 78 orders, 177 families, and 307 genera. The dominant phyla in the lake were Ascomycota, Basidiomycota and Chytridiomycota. Our results show that both water and sediments have very high connectivity, are dominated by positive interactions, and have similar interaction patterns. The fungal community structures were found to be significantly affected by environmental factors (temperature, chemical oxygen demand, electrical conductivity, total phosphorus, and pH). In addition, the dispersal limitations of the fungi affected the structure of the fungal communities, and it was revealed that stochasticity is more important than deterministic mechanisms in influencing the structure and function of fungal communities. This study provides unique theoretical support for the study of seasonally frozen lake fungal communities and a scientific basis for the future management and protection of Hulun Lake.
Synthetic Observations of 21 cm H i Line Profiles from Inhomogeneous Turbulent Interstellar H i Gas with Magnetic Fields

We carried out synthetic observations of interstellar atomic hydrogen at 21 cm wavelength by utilizing the magnetohydrodynamic numerical simulations of the inhomogeneous turbulent interstellar medium. The cold neutral medium (CNM) shows a significantly clumpy distribution with a small volume filling factor of 3.5%, whereas the warm neutral medium (WNM) has a distinctly different and smooth distribution with a large filling factor of 96.5%. In projection on the sky, the CNM exhibits a highly filamentary distribution with a subparsec width, whereas the WNM shows a smooth, extended distribution. In the H i optical depth, the CNM is dominant and the contribution of the WNM is negligibly small. The CNM has an area covering factor of 30% in projection, while the WNM has a covering factor of 70%. This means that the emission–absorption measurements toward radio continuum compact sources tend to sample the WNM with a probability of 70%, yielding a smaller H i optical depth and a smaller H i column density than those of the bulk H i gas. The emission–absorption measurements, which are significantly affected by the small-scale large fluctuations of the CNM properties, are not suitable for characterizing the bulk H i gas. Larger-beam emission measurements that are able to fully sample the H i gas will provide a better tool for that purpose, if a reliable proxy for hydrogen column density, possibly dust optical depth and gamma rays, is available. The present results provide a step toward precise measurements of the interstellar hydrogen with ∼10% accuracy. This will be crucial in interstellar physics, including identification of the proton–proton interaction in gamma-ray supernova remnants.
Using Reader Response Strategy and Affective Learning Domain in Teaching Literature to Enhance Critical Thinking

Reading comprehension has been a perennial problem for Filipino students which was reflected in the Program for International Student Assessment (PISA) and in San Bartolome Integrated High School’s Secondary Reading Inventory (SRI) which showed that 281 out of 920 students were at the frustration level of reading. The strategy used by the teacher and reading interest of the students affect students’ learning. This experimental study aimed to find out the effect of Reader Response Strategy in teaching literature and affective learning domain on the level of critical thinking competence among grade 11 senior high school students at San Bartolome Integrated High School for school year 2019-2020. Forty (40) randomly selected grade 11 students served as respondents. Researcher-made 40-item pre-test and posttest on critical thinking competence, and as affective learning inventory were used as instruments. The respondents perceived that the first three levels of affective learning domain namely receiving, responding and valuing are evident in them. They are unsure of their perception of their organizing domain. They do not perceive characterizing is in their system. The respondents showed improvement in three out of four critical thinking competencies namely defining, classifying and drawing conclusions after exposure to Reader Response Strategy. However, there was no improvement in the respondents’ skills in finding relationships. There is no significant relationship between the respondents’ critical thinking competencies and their affective learning domain. It is recommended that Reader Response Strategy may be adopted for a longer period of time to ensure positive results in learners’ overall reading comprehension skills.
Very Thin Disc Galaxies in The SDSS Catalog of Edge-on Galaxies

We study the properties of galaxies with very thin discs using a sample of 85 objects whose stellar disc radial-to-vertical scale ratio determined from photometric decomposition, exceeds nine. We present evidences of similarities between the very thin disc galaxies (VTD galaxies) and low surface brightness (LSB) disc galaxies, and conclude that both small and giant LSB galaxies may reveal themselves as VTD, edge-on galaxies. Our VTD galaxies are mostly bulgeless, and those with large radial scale length tend to have redder colors. We performed spectral observations of 22 VTD galaxies with the Dual Imaging Spectrograph on the 3.5m telescope at the Apache Point Observatory. The spectra with good resolution (R ~ 5000) allow us to determine the distance and the ionized gas rotation curve maximum for the galaxies. Our VTD galaxies have low dust content, in contrast to regular disc galaxies. Apparently, VTD galaxies reside in specific cosmological low-density environments and tend to have less connection with filaments. Comparing a toy model that assumes marginally low star formation in galactic discs with obtained gas kinematics data, we conclude that there is a threshold central surface density of about 88 Mo/pc**2, which we observe in the case of very thin, rotationally supported galactic discs.