Miracle-dz/UniFAR-FTUs huggingface dataset:
The origin of dust in galaxies revisited: the mechanism determining dust content

The origin of cosmic dust is a fundamental issue in planetary science. This paper revisits the origin of dust in galaxies, in particular, in the Milky Way, by using a chemical evolution model of a galaxy composed of stars, interstellar medium, metals (elements heavier than helium), and dust. We start from a review of time-evolutionary equations of the four components, and then, we present simple recipes for the stellar remnant mass and yields of metal and dust based on models of stellar nucleosynthesis and dust formation. After calibrating some model parameters with the data from the solar neighborhood, we have confirmed a shortage of the stellar-dust-production rate relative to the dust-destruction rate by supernovae if the destruction efficiency suggested by theoretical works is correct. If the dust-mass growth by material accretion in molecular clouds is active, the observed dust amount in the solar neighborhood is reproduced. We present a clear analytic explanation of the mechanism for determining dust content in galaxies after the activation of accretion growth: a balance between accretion growth and supernova destruction. Thus, the dust content is independent of the uncertainty of the stellar dust yield after the growth activation. The timing of the activation is determined by a critical metal mass fraction which depends on the growth and destruction efficiencies. The solar system formation seems to have occurred well after the activation and plenty of dust would have existed in the proto-solar nebula.
Why do descending Shells around Cumulus Clouds exist

In search of better descriptions of shallow cumulus clouds, the main focus lies more and more on the dynamical properties and microphysical structure of the clouds and on its interaction with the environment (e.g. (Siebesma and Cuijpers, 1995)). For this type of study, sufficient statistics of the three dimensional flow are needed, which is usually better provided by Large Eddy Simulations (LES) than by experimental data, which often can provide one(e.g. airplane measurements) or two-dimensional (satellites) data. While LES has proven to be an extremely useful tool to investigate these cloud dynamics, comparisons between LES and experimental remains desireable. Usually, (e.g. (Siebesma et al., 2003), (Stevens et al., 2001) and (Neggers et al., 2003)) only slab-averaged fields and derived quantities are compared with observations. This study focuses on detailed lateral profiles of the main (thermo)dynamic variables, conditionally averaged over clouds and surroundings similar to the study by (Rodts et al., 2003) on observational data (From here onwards referred to as [RDJ03]). The method of post-processing used by [RDJ03] is based on a method where the 1-D data is conditionally averaged over the cloud and its environment. This resulted in lateral profiles of the various properties of the cloud as a function of the normalized horizontal position in the cloud. Not only the average values were obtained in this way, but also the variance around these averages, which can be seen as an estimate for the turbulence. Comparing [RDJ03] with LES provides a new and interesting validation of the detailed dynamical structure of the simulations. To obtain optimal comparison, the post processing of the numerical results is closely modeled to the method used for the observational data enabling direct comparison and providing insight in a natural way. Emphasis will be placed on the role of a shell of descending air found around shallow cumulus clouds not only by [RDJ03], but also reported in earlier studies (e.g. (Jonas, 1990), abbreviate as [J90]). Discussion on this shell is usually directly linked to the significance of lateral mixing over cloud edge. In literature (e.g. (Paluch, 1979), (Blyth, 1993)), lateral mixing is considered to be of much less importance to cloud dynamics than cloud-top mixing. If this also holds for this shell, as [J90] suggested, the shell has to be driven by a mechanical forcing through the pressure-gradient force. However, this is questioned by [RDJ03], who advocates that the descending motion is driven by evaporative cooling following lateral mixing
An optimized energy harvester for moving mass induced vibration

This paper presents a piezoelectric energy harvester by which the vibration energy induced by a moving mass is converted to electrical energy through the piezoelectric effect. An electromechanically coupled finite element model (FEM) based on the Euler–Bernoulli beam theory is employed to estimate the electrical energy that can be generated by the energy harvester. The effects of mass ratio, beam length, travel time and load resistance on the energy output are examined. Experiments are conducted to verify the numerical model. The experimental results are in good agreement with the numerical prediction. In the design stage, the nonlinear conjugate gradient (CG) algorithm is applied for the calculation to maximize the energy throughput from the energy harvester. Results have shown that the harvested energy depends heavily upon the optimal choice of load resistance and travel time of the moving mass. In addition, the longer the beam or the higher the mass ratio, the higher the energy throughput that can be achieved.
Flows, Bits, Relationships: Construction of Deep Spatial Understanding

Author(s): Sandoval Olascoaga, Carlos; Faichney, John | Abstract: The number of variables acting upon urban landscapes is numerous and interconnected, closely resembling complex systems in constant dynamic transformation. Current analytical methods and descriptions of the city are domain specific, limited in scope, and discretize the city into quantifiable individual representations, resulting in an equally limited urban policy and design. If we are to produce urban systems capable of contributing to the robustness and resiliency of cities, we ought to understand and represent the comprehensive network of actors that construct contemporary urban landscapes. On one hand, the natural sciences approach the analysis of complex systems by primarily focusing on the development of models capable of describing their stochastic formation, remaining agnostic to the contextual properties of their individual components and oftentimes discretizing the otherwise continuous relationships among parts. signers work in groups. They need to share information either synchronously or asynchronously as they work with parametric modeling software, as with all computer-aided design tools. Receiving information from collaborators while working may intrude on their work and thought processes. Little research exists on how the reception of design updates influences designers in their work. Nor do we know much about designer preferences for collaboration. In this paper, we examine how sharing and receiving design updates affects designers’ performances and preferences. We present a system prototype to share changes on demand or in continuous mode while performing design tasks. A pilot study measuring the preferences of nine pairs of designers for different combinations of control modes and design tasks shows statistically significant differences between the task types and control modes. The types of tasks affect the preferences of users to the types of control modes. In an apparent contradiction, user preference of control modes contradicts task performance time.
INVESTIGATING STUDENTS’ LEARNING DIFFICULTIES IN INTEGRAL CALCULUS

The study aims to investigate the students’ learning difficulties in Integral Calculus, specifically in calculating integrals. The mixed methods research design was employed to gather quantitative data from the student s’ answers in the examination and collect qualitative data from them through open-ended interviews and scrutiny of their solutions. Findings of related previous investigations were documented to understand more the nature of the difficulties in the subject as experienced by others. Participants of the study were given the examination in indefinite integrals composed of items that require solely the use of integration formulas and items in which integration techniques should be applied. The quantitative data disclosed, after subjecting the index of difficulties to statistical treatment, that the learners have experienced the same level of difficulties in dealing with the two types of integrals. The qualitative data revealed, as viewed by the participants and as reflected in their solutions, that many of the errors pertain more to the learners’ ability in trigonometric manipulation rather than with the integration per se. It was further concluded as highlighted from previous studies, that the learners’ difficulties in integration are evidently attributed to the inherent mathematical knowledge and skills acquired by the students from basic mathematics.
Influence of temperature on food consumption and utilization parameters of the common cutworm, Spodoptera litura (Fab.) (Lepidoptera: Noctuidae)

Laboratory experiments were conducted to assess the influence of controlled temperature regimes (20, 25 and 30 oC) on the nutritional parameters of different host plants (castor, cabbage and tomato) by the last larval instar of Spodoptera litura (Fab.) on dry weight basis. The results of the present study indicated that the temperature (30 °C) was favourable for the food consumption and utilization of castor, cabbage and tomato by the 6 instar S. litura larva. The pattern of the nutritional indices on the three host plants at 30 oC revealed high feeding and food assimilation activities as characterized by significantly higher values for relative consumption rate (RCR), relative growth rate index (RGR), the efficiency of conversion of ingested food (ECI) and digested food (ECD). The values of larval approximate digestibility (AD) on the three host plants were significantly higher at 2 5oC and least at 30oC. The reduced food consumption and utilization by 6 instar S. litura at 20 oC was evidenced by the low feeding activity as well as the relatively reduced capacity to assimilate the food materials.
Three new fossil landbirds from the early Paleogene of Denmark

Well-preserved remains of fossil modern birds are rare, especially from the earliest stages of their evolution. In this paper we describe three new fossil specimens that can be referred to two of the major clades of extant ‘landbirds’, namely Apodiformes (‘swifts’) and Coliiformes (‘mousebirds’). Because the fossils presented here are from the earliest tertiary of Denmark, they represent some of the oldest certain records for both these major clades of modern birds (Neornithes). This new material, from the Paleocene – Lower Eocene Fur Formation (Isle-of-Mors, Jutland, Denmark) is referred to the fossil apodiform genus Eocypselus Harrison, 1984 and the coliiform genus Chascacocolius Houde & Olson, 1992. Eocypselus has been referred to within the clade Hemiprocnidae (‘tree and crested swifts’) and Chascacocolius to the Sandcoleidae, a clade of stem representatives of extant Coliiformes. The description of Chascacocolius from the Danish early tertiary increases the known diversity of stem-lineage coliiforms (Sandcoleidae) known from European deposits. New fossil material of Eocypselus shows that this taxon was a perching bird as are extant hemiprocnids – the hindlimb and foot of Eocypselus is elongate and anisodactyl, with digit III the longest of the pedal digits. Swifts and mousebirds are known to have been diverse in the earliest tertiary of Europe and North America; both these neornithine clades have a much lower extant diversity in terms of known species than that evidenced by their global fossil records, a temporal effect perhaps related to global cooling throughout the latest tertiary.
Reduction of the Weaving Process Set-up Time through Multi-Objective Self-Optimization

Real (physical) objects melt together with information-processing (virtual) objects. These blends are called Cyber-Physical Production Systems (CPPS). The German government identifies this technological revolution as the fourth step of industrialization (Industry 4.0). Through embedding of intelligent, self-optimizing CPPS in process chains, productivity of manufacturing companies and quality of goods can be increased. Textile producers especially in high-wage countries have to cope with the trend towards smaller lot sizes in combination with the demand for increasing product variations. One possibility to cope with these changing market trends consists in manufacturing with CPPS and cognitive machinery. This paper focuses on woven fabric production and presents a method for multiobjective self-optimization of the weaving process. Multi-objective self-optimization assists the operator in setting weaving machine parameters according to the objective functions warp tension, energy consumption and fabric quality. Individual preferences of customers and plant management are integrated into the optimization routine. The implementation of desirability functions together with Nelder/Mead algorithm in a software-based Programmable Logic Controller (soft-PLC) is presented. The self-optimization routine enables a weaving machine to calculate the optimal parameter settings autonomously. Set-up time is reduced by 75% and objective functions are improved by at least 14% compared to manual machine settings.
Informational Quality of Financial Systems and Economic Development: An Indicators Approach for East Asia

The relation between the "informational quality" of financial systems and economic development is assessed for 21 OECD and 34 emerging market economies (EMEs) following Asia's 1997-98 crisis. Institutional economics suggest that the heart of any financial system is its institutional-informational infrastructure and long-term contracting capabilities. Twenty-seven microeconomic and institutional indicators are assessed to gauge the informational aspects of financial systems for 1995-1998 (with preliminary data for 1985). Recent institutional reforms are assessed vis-a-vis a statistical benchmark. This suggests disproportionate gains in per capita GDP from improving social infrastructure and that better enforcement rather than origins of legal systems are critical.
Automatic Measurement of Semantic Similarity among Arabic Short Texts

Documents that are dealing with the same topic include normally many identical words. Accordingly, surface words co-occurrence similarity measures has been applied successfully to measure the similarity between these documents. However, the problem is not a trivial task when dealing with short texts that carry the same or close meaning but with different vocabularies. Toward solving this problem, researchers have been investigating methods for word analysis at the semantic level. We introduce a new method to measure the semantic similarity between short texts. In the proposed method, semantic distribution and lexical similarity measures are combined to determine the degree of similarity between two words. The similarity between two words is measured as the lexical similarity between the vectors of similar words extracted from corpus as a second order word vector. The proposed method was applied to measure the semantic similarity between Arabic short texts. The experiments performed showed that the best accuracy achieved by the proposed method was 97% compared to 93% recorded for the second order distribution similarity.
A study on discrimination of SIFT feature applied to binary images

Scale Invariant Feature Transform (SIFT) since its first apparition in 2004 has been (and still is) extensively used in computer vision to classify and match objects in RGB and grey level images and videos. However, since the descriptor used in SIFT approach is based on gradient magnitude and orientation, it has always been considered as texture feature and received less interest when treating binary images. In this work we investigate the power of discrimination of SIFT applied to binary images. A theoretical and experimental studies show that SIFT can still describe shapes and can be used to distinguish objects of several classes.
The Effect of Seed Size Variation in Quercus pacifica on Seedling Establishment and Growth 1

Quercus pacifica, the island scrub-oak, is the dominant species in oak chaparral on the three largest California Channel Islands. While the population on Santa Cruz Island has experienced a strong recovery, the populations on Santa Rosa and Santa Catalina islands are of conservation concern, and managers are actively restoring oak habitat by planting acorns. Previous work shows that acorn size, a factor that is known to affect planting success, varies significantly across the range of the species. To determine whether acorn size in Q. pacifica affects early seedling growth, I planted over 600 acorns from Santa Cruz Island in a greenhouse. Our results show that larger acorns are more likely to germinate, and that acorn mass had strong effects on root mass, shoot mass, seedling height and leaf surface area. Assuming that acorn size may have a similar effect on Santa Rosa and Santa Catalina, I suggest that managers plant larger acorns to maximize the effect of restoration efforts.
Piecewise Negative Binomial Regression in Analyzing Hypoglycemic Events with Missing Observations

In diabetes clinical trials, hypoglycemia can be captured. Negative binomial regression is emerging as a standard method for analyzing hypoglycemic events by considering overdispersion. However, in negative binomial regression for hypoglycemic events, variability of the subjects lost to follow up due to dropout is adjusted through an offset parameter, which assumes that dropout is missing completely at random and constant hypoglycemia rate over time. This assumption is vulnerable because dropout may be due to the excessive observed hypoglycemic events and the hypoglycemic event rate may change over time. In addition, the traditional way of using negative binomial regression to analyze hypoglycemic events only compares the counts of hypoglycemic events during a specified period. However, researchers may be interested in comparing hypoglycemic event rates between treatment groups at different time periods to understand the trend over time. Fitting a negative binomial model for each time period ignoring data from other periods may decrease testing power and introduce bias if the assumption of missing completely at random does not hold. We propose piecewise negative binomial regression to incorporate multiple time periods in one model through a generalized linear mixed-effect model. Due to clinical interest, we considered multiple weighting methods to estimate the overall relative rate of hypoglycemia over multiple periods between treatments. Simulations showed that piecewise negative binomial regression performed better than the traditional negative binomial regression in preserving Type I error. As an illustration, piecewise negative binomial regression was implemented in analyzing real data from a Type 2 diabetes clinical trial.
Optimization of shrimp shell waste deacetylation for chitosan production

Article history: Received 12 August 2016 Received in revised form 5 October 2016 Accepted 11 October 2016 Chitosan, a versatile natural polymer is an amino polysaccharide prepared by processing shrimp shell waste which involved deacetylation of chitin. To obtain high degree of deacetylation (DDA), several parameters should be performed during alkaline treatment. The present study was undertaken at different time of soaking treatment (once and twice) and temperature (60oC and 80oC) to optimize the deacetylation process to produce chitosan with high solubility and degree of deacetylation. It was observed that the highest solubility and degree of deacetylation were obtained when deacetylation process was repeated twice and temperature of 80oC, with 99.48% and 97.63%, respectively. It can be concluded that by repeating the deacetylation twice with the support of heating treatment, a better quality of chitosan with higher solubility and degree of deacetylation can be produced.
EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH CERN AB DIVISION

Modern RF structures make great demands on both materials and fabrication techniques. In addition to high required precision, they need to be compatible with ultra high vacuum, high power RF and the presence of particle beams. We introduce materials compatible with these demands and summarize their relevant characteristics. Methods of forming and joining follow, again with emphasis on those suited for the fabrication of accelerating structures, and we point out their limitations. We mention different tests which will be designed into the fabrication process, and describe in some detail the testing of the RF properties of accelerating structures. The following overview is non-exhaustive and limited to normalconducting structures; many of the examples relate to a possible next-generation linear collider.
The multifrequency emission of Mrk 501 From radio to TeV gamma-rays

We present two-epoch, multifrequency complete modeling of Mrk 501 broad band emission from the radio frequencies up to the very high gamma ray regime as observed during April 1997 outburst. To reproduce the X-ray and the gamma-ray radiation we assume an homogeneous Synchrotron-Self-Compton (SSC) model and approximate the electrons energy distribution by a broken power-law function with a sharp cut-o at high energy. We assume also spherical geometry of the emitting region (a blob) and uniform magnetic eld. For this scenario we derive constrains on physical parameters obtained from the observable quantities and can reproduce very well the observed Very High Energy (VHE) spectra. We nd that the two dierent high energy states cannot be explained by varying the particle energy distribution only. To obtain good spectral ts we have to change additionally one of the global parameters which describe the emitting blob: the magnetic eld intensity (B), the radius (Rb )o r the Doppler factor (b). We use a model of an inhomogeneous conical jet to explain radiation from the low radio frequencies up to the ultraviolet. A part of the physical parameters of this jet can be constrained from our ts of the high energy emission. The remaining parameters are estimated independently from other observations. We assume that the blob is placed somewhere inside the jet, relatively close to the central engine. Within this \blob- in-jet" scenario we analyze the eect of External Inverse-Compton (EIC) scattering of low energy synchrotron photons from the jet and thermal radiation surrounding the central engine. We show that EIC scattering can also very well explain VHE emission of Mrk 501 when external radiation is dominated by photons from the jet itself, which is an interesting alternative of the \blob-in-jet" scenario. Additional inverse-Compton scattering of relatively weak thermal external radiation cannot explain alone the spectra but can signicantly modify them, especially in the sub-TeV range, in comparison to spectral shape generated only with SSC model. We also analyze the absorption eect due to pair-production inside the source, which appears almost negligible. The same eect in the Intergalactic Infrared Background (IIB) may introduce signicant changes to the observed VHE spectra. In the infrared and optical parts of the spectrum, the contribution of the host galaxy is well reproduced by an elliptical galaxy evolution model. Three miniflares of Mrk 501 occurred in ten days between 7 and 16 April 1997 at the X-ray and gamma-ray frequencies. They can be well reproduced by simple variation of the break in the electron energy distribution function on time scale of a few hours, superposed to variation of the blob radius and of the particle density on time scale of about two days.