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This paper explores questions surrounding corporeality and heavenly ascent, in texts ranging from 1 Enoch to the Hekhalot literature, including Philo’s works. It examines both descriptions of the heavenly realms and accounts of the ascent process. Despite his Platonic apophaticism, Philo superimposes cosmological and spiritual heavens, and draws upon the biblical imagery of dazzling glory. Although they do not express themselves in philosophical language, the heavenly ascent texts make it clear that human beings cannot ascend to heaven in their earthly bodies, and that God cannot be seen with terrestrial eyes. In terms of ideas they are not so far from the philosopher Philo as might at first appear.
My essay attends to a number of passages in Alexander von Humboldt’s Personal Narrative in which the Prussian explorer expresses anxiety about the apparent dangers posed by the overwhelmingly productive tropical landscapes he observes. In these passages, the excesses of an “exotic nature” threaten European identity and modes of civilization—and they trouble the accuracy of Humboldt’s own observational project. I also explore Humboldt’s related worry that South American vegetable (and visual) overload will exert a destabilizing effect on his aesthetic sensibility, disrupting his ability to represent the “New Continent” accurately in writing. Finally, I sketch the influence of Humboldt’s representations of tropical excess on nineteenth-century British cultural thought and literary practice. Studying the instabilities experienced by Personal Narrative’s expatriates and colonists promises to draw out important tensions latent in Humboldt’s treatment of tropical landscape and to illuminate broader epistemological and aesthetic shifts being worked out during the period.
“One video fit for all”
(2023)
Online learning in mathematics has always been challenging, especially for mathematics in STEM education. This paper presents how to make “one fit for all” lecture videos for mathematics in STEM education. In general, we do believe that there is no such thing as “one fit for all” video. The curriculum requires a high level of prior knowledge in mathematics from high school to get a good understanding, and the variation of prior knowledge levels among STEM education students is often high. This creates challenges for both online teaching and on-campus teaching. This article presents experimenting and researching on a video format where students can get a real-time feeling, and which fits their needs regarding their existing prior knowledge. They have the possibility to ask and receive answers during the video without having to feel that they must jump into different sources, which helps to reduce unnecessary distractions. The fundamental video format presented here is that of dynamic branching videos, which has to little degree been researched in education related studies. The reason might be that this field is quite new for higher education, and there is relatively high requirement on the video editing skills from the teachers’ side considering the platforms that are available so far. The videos are implemented for engineering students who take the Linear Algebra course at the Norwegian University of Science and Technology in spring 2023. Feedback from the students gathered via anonymous surveys so far (N = 21) is very positive. With the high suitability for online teaching, this video format might lead the trend of online learning in the future. The design and implementation of dynamic videos in mathematics in higher education was presented for the first time at the EMOOCs conference 2023.
In 1810, Moses Lackenbacher, together with two of his children, Israel and Heinrich, and Moses Löwenstein created the company “Moses Lackenbacher & Compagnie” with headquarters in Nagykanizsa and a branch in Vienna. The main profile of the company was army purveyance. The business activity resulted in a high spatial mobility which led to socio-cultural acculturation and conversions to Christianity within the kinship. This paper explores the connection between kinship and the operation of the company on the basis of the prominent yet little-researched Lackenbachers in the early 19th-century Habsburg Monarchy. Central questions are how the relatives organized a company during the Napoleonic wars, as well as the impact of operating a business; how familial bonds and kinship links were affected, and, in this context, how relatives together evolved into a multi-religious network of kinship.
“Mason without apron”
(2019)
While the lack of religion in Alexander von Humboldt’s work and the criticism he received is well known, his relationship with Freemasonry is relatively unexplored. Humboldt appears on some lists of “illustrious Masons,” and several lodges carry his name, but was he really a member? If so, when and where did he join a lodge? Are there any comments by him about Freemasonry? Who were the renowned Masons he was surrounded by? This paper examines these questions, but more importantly it analyzes what a membership might have meant for Humboldt’s scholarly work. It looks particularly at the unprecedented success he enjoyed in the United States in the early 19th century and the factors behind it. What could he have gained from these connections and how was he viewed by Masonic leaders and lodges in the trans-Atlantic world?
“Israel am Meere”
(2023)
For Jews in Germany, the period following the Nazis’ rise to power in January 1933 was a period of decision-making on many levels: How should they respond to the persecution? If they decided to emigrate, many more decisions had to be made: How does one leave a country, and where should one go? A key moment in the process and in the cultural practice of emigration is the beginning of the sea voyage – when the need for departure and the hope for a new arrival jointly create a period of liminality. Looking at reports from sea voyages of exploration and emigration from the 1930s, this contribution discusses the question whether, and in what ways, such reflections can be read in the context of religious experiences and in the search for Jewish identities in times of turmoil.
A quote from Fight Club (Chuck Palahniuk, 1996) may seem unusual for a Classicist. Nevertheless, this famous sentence summarises the contents of this special issue of thersites perfectly. As specialists in classical reception frequently witness, there is a sort of déjà-vu effect when it comes to the presence of Antiquity within popular culture. In 2019, to try to better understand the phenomenon, Antiquipop invited researchers to take an interest in the construction and semantic path of these “masterpieces” in contemporary popular culture, with a particular focus on the 21st century.
“Domestic Foreigners”
(2024)
This paper examines the relationship between the Sephardic Jewish community of Vienna and the Ottoman and Habsburg Empires in the latter half of the 19th century. The community’s legal status was transformed following the emancipation of Austrian Jews, but very few first-hand accounts of these changes exist today. The primary sources analyzed in this paper are Judezmo-language newspapers published in Vienna at that time. The paper emphasizes the historical and political contexts surrounding these sources, particularly the community’s close ties to the Ottoman and Habsburg regimes.
“Creating a Maritime Future”
(2023)
This article explores the importance of the port city of Hamburg in the evolving discourses on the creation of a maritime future, a vision which became influential in the 1930s, 1940s and 1950s. While some Jewish representatives in the city aimed at preserving and intertwining Hanseatic and Jewish traditions in order to secure a Jewish presence in the port city under the pressure of the Nazi regime and thereafter, others wanted to create new emigration opportunities, especially to Mandatory Palestine, and create a Jewish maritime future in Eretz Israel. Different Zionist organizations supported the newly evolving maritime ideas, such as the “conquest of the sea”, and promoted the image of a Jewish seafaring nation. Despite the difficulties in the 1940s, these concepts gained influence post-1945 and led to the foundation of the fishery kibbutz “Zerubavel” in Blankenese/Hamburg. However, the idea of a Hanseatic Jewish future also remained influential and illustrates how differently a “Jewish maritime future” was imagined and used to link past, present and future.
Even though Salonican Jews are not typically associated with the Habsburg Empire, some of them, nonetheless, lived there. This paper aims to examine the formation of these Salonican Jews’ (self-)identification by studying their social interactions with the local Viennese population such as the Viennese Sephardi or the Greek-Orthodox communities. The change of the milieu within which they found themselves subsequently impacted their self-perception. Thus, the issue of the surrounding environment and their relations with other groups became central to their self-understanding, as will be demonstrated. By examining different aspects, like migration patterns, financial decisions and family ties, one can understand how their intersection influenced Salonica Jews’ self-identification, which, at the same time, shaped and was shaped by the surrounding milieu. Within this framework, these people perceived themselves and were perceived as Salonican, Sephardi, Jewish, and as subjects of the Emperor.
‘Crazy Man-Killing Monsters’
(2023)
The Amazons have a long legacy in literature and the visual arts, extending from antiquity to the present day. Prior scholarship tends to treat the Amazons as hostile ‘Other’ figures, embodying the antithesis of Greco-Roman cultural norms. Recently, scholars have begun to examine positive portrayals of Amazons in contemporary media, as role models and heroic figures. However, there is a dearth of scholarship examining the Amazons’ inherently multifaceted nature, and their subsequent polarised reception in popular media.
This article builds upon the large body of scholarship on contemporary Amazon narratives, in which the figures of Wonder Woman and Xena, Warrior Princess dominate scholarly discourse. These ‘modern Amazon’ figures epitomise the dominant contemporary trend of portraying Amazons as strong female role models and feminist icons. To highlight the complexity of the Amazon image in contemporary media, this article examines the representation of the Amazons in the Supernatural episode ‘Slice Girls’ (S7 E13, 2012), where their portrayal as hostile, monstrous figures diverges greatly from the positive characterisation of Wonder Woman and Xena. I also consider the show’s engagement with ancient written sources, to examine how the writers draw upon the motifs of ancient Amazon narratives when crafting their unique Amazon characters. By contrasting the Amazons of ‘Slice Girls’ to contemporary figures and ancient narratives, this article examines how factors such as feminist ideology, narrative story arcs, characters’/audience’s perspectives and male bias shape the representation of Amazons post-antiquity.
The paper discusses the distribution and meaning of the additive particle -m@s in Ishkashimi. -m@s receives different semantic associations while staying in the same syntactic position. Thus, structurally combined with an object, it can semantically associate with the focused object or with the whole focused VP; similarly, combined with the subject it can semantically associate with the focused subject and with the whole focused sentence.
After the mass immigration to Israel from 1948 to 1950, about 2000 Jews remained
in Yemen. These Jews lived in small communities and continued to maintain their
religious environment as it was. In the years that followed, many of them, however, moved from Yemen to Israel with the assistance of the Jewish Agency and the Joint
Distribution Committee (JDC). The community was of a small size and the fact that it
was dispersed throughout the predominantly Muslim areas, created a certain closeness
between the two groups. About ten percent of the Jews chose to convert to Islam, many
of them in groups. In about twenty cases, the husbands chose to convert to Islam while
their wives emigrated to preserve their Judaism. Some of the converts refused to grant
their wives a divorce, because, according to Muslim law, conversion is enough to sever
the marital relationship. This procedure is called ʿAgunot. Meaning, women bound in
marriage to a husband and they no longer lived together, but the husband didn’t formally
‘released’ her from marriage union. The article follows the efforts undertaken
to release the ʿAgunot, and shows that Jewish and Muslim scholars were able to find
solutions to the ʿAgunot problem and, at times, managed to bridge the gap between the
two religions.
Several zwitterionic polymers were prepared by radical homopolymerization of surfactant monomers which bear diallyl, diene or vinylcyclopropane moieties. These polymer systems were complemented by alternating copolymers of appropriate zwitterionic vinyl compounds. Thus, polymers with reduced (as compared with simple vinylic homopolymers, or statistical copolymers) and well defined density of surfactant side groups are obtained. The solubilities found for these polymers are dominated by polymer geometry rather than by the balance of hydrophilic and hydrophobic fragments, thus corroborating a main-chain spacer model proposed recently. All water-soluble polymers exhibit characteristic features of classical polysoaps, as shown by surface tension measurements and by solubilization of hydrophobic dyes. In contrast, the water-insoluble copolymers are capable to form stable monolayers at the air-water interface.
In 1945, Zinovii Shenderovich Tolkatchev (1903–1977), a Soviet artist of Jewish origin, created a striking series of five images entitled “Jesus in Majdanek”. The series was the culmination of Tolkatchev‘s intensive preoccupation with the experience he, as a Red Army soldier, endured upon taking part in liberation of the concentration camps Majdanek and Auschwitz. Shocked by the actual sights he witnessed, he depicted Jesus as an actual camp inmate, wearing a striped uniform marked by every possible defamation sign – the Jewish yellow star, the red triangle of political prisoners, and the individual prison number, the numerical tattoo on his lower arm can also be seen. The different stages of camp life are portrayed as the traditional Passion of Christ. While showing the actual situations the artist based himself upon the well known European Renaissance paintings canonically depicting Jesus‘ suffering. The article places Tolkatchev‘s series in a broader cultural and visual context by exploring the development of the ‘historical Jesus’ in the 19th century European thought and Russian realist art, and by examining the impact of the German avant-garde. By doing so, a deeper understanding of the universal message Tolkatchev’s works entail is offered.
Given a system of entire functions in Cn with at most countable set of common zeros, we introduce the concept of zeta-function associated with the system. Under reasonable assumptions on the system, the zeta-function is well defined for all s ∈ Zn with sufficiently large components. Using residue theory we get an integral representation for the zeta-function which allows us to construct an analytic extension of the zeta-function to an infinite cone in Cn.
rezensiertes Werk: Schwartz, Yigal: Maamin beli Kenessija : 4 Massot al Aharon Appelfeld. - Tel Aviv : Dvir, 2009.- 181 S.
rezensiertes Werk: Shraibman, Yechiel: Sieben Jahre und sieben Monate : meine Bukarester Jahre ; Roman. - Berlin : be.bra, 2009. - 272 S. ISBN 978-3-937233-56-7
We introduce a simple approach extending the input language of Answer Set Programming (ASP) systems by multi-valued propositions. Our approach is implemented as a (prototypical) preprocessor translating logic programs with multi-valued propositions into logic programs with Boolean propositions only. Our translation is modular and heavily benefits from the expressive input language of ASP. The resulting approach, along with its implementation, allows for solving interesting constraint satisfaction problems in ASP, showing a good performance.
xMOOCs
(2023)
The World Health Organization designed OpenWHO.org to provide an inclusive and accessible online environment to equip learners across the globe with critical up-to-date information and to be able to effectively protect themselves in health emergencies. The platform thus focuses on the eXtended Massive Open Online Course (xMOOC) modality – contentfocused and expert-driven, one-to-many modelled, and self-paced for scalable learning. In this paper, we describe how OpenWHO utilized xMOOCs to reach mass audiences during the COVID-19 pandemic; the paper specifically examines the accessibility, language inclusivity and adaptability of hosted xMOOCs. As of February 2023, OpenWHO had 7.5 million enrolments across 200 xMOOCs on health emergency, epidemic, pandemic and other public health topics available across 65 languages, including 46 courses targeted for the COVID-19 pandemic. Our results suggest that the xMOOC modality allowed OpenWHO to expand learning during the pandemic to previously underrepresented groups, including women, participants ages 70 and older, and learners younger than age 20. The OpenWHO use case shows that xMOOCs should be considered when there is a need for massive knowledge transfer in health emergency situations, yet the approach should be context-specific according to the type of health emergency, targeted population and region. Our evidence also supports previous calls to put intervention elements that contribute to removing barriers to access at the core of learning and health information dissemination. Equity must be the fundamental principle and organizing criteria for public health work.
X-ray spectroscopy is a sensitive probe of stellar winds. X-rays originate from optically thin shock-heated plasma deep inside the wind and propagate outwards throughout absorbing cool material. Recent analyses of the line ratios from He-like ions in the X-ray spectra of O-stars highlighted problems with this general paradigm: the measured line ratios of highest ions are consistent with the location of the hottest X-ray emitting plasma very close to the base of the wind, perhaps indicating the presence of a corona, while measurements from lower ions conform with the wind-embedded shock model. Generally, to correctly model the emerging Xray spectra, a detailed knowledge of the cool wind opacities based on stellar atmosphere models is prerequisite. A nearly grey stellar wind opacity for the X-rays is deduced from the analyses of high-resolution X-ray spectra. This indicates that the stellar winds are strongly clumped. Furthermore, the nearly symmetric shape of X-ray emission line profiles can be explained if the wind clumps are radially compressed. In massive binaries the orbital variations of X-ray emission allow to probe the opacity of the stellar wind; results support the picture of strong wind clumping. In high-mass X-ray binaries, the stochastic X-ray variability and the extend of the stellar-wind part photoionized by X-rays provide further strong evidence that stellar winds consist of dense clumps.
We summarize Chandra observations of the emission line profiles from 17 OB stars. The lines tend to be broad and unshifted. The forbidden/intercombination line ratios arising from Helium-like ions provide radial distance information for the X-ray emission sources, while the H-like to He-like line ratios provide X-ray temperatures, and thus also source temperature versus radius distributions. OB stars usually show power law differential emission measure distributions versus temperature. In models of bow shocks, we find a power law differential emission measure, a wide range of ion stages, and the bow shock flow around the clumps provides transverse velocities comparable to HWHM values. We find that the bow shock results for the line profile properties, consistent with the observations of X-ray line emission for a broad range of OB star properties.
Using a code that employs a self-consistent method for computing the effects of photoionization on circumstellar gas dynamics, we model the formation of wind-driven nebulae around massive Wolf-Rayet (W-R) stars. Our algorithm incorporates a simplified model of the photo-ionization source, computes the fractional ionization of hydrogen due to the photoionizing flux and recombination, and determines self-consistently the energy balance due to ionization, photo-heating and radiative cooling. We take into account changes in stellar properties and mass-loss over the star's evolution. Our multi-dimensional simulations clearly reveal the presence of strong ionization front instabilities. Using various X-ray emission models, and abundances consistent with those derived for W-R nebulae, we compute the X-ray flux and spectra from our wind bubble models. We show the evolution of the X-ray spectral features with time over the evolution of the star, taking the absorption of the X-rays by the ionized bubble into account. Our simulated X-ray spectra compare reasonably well with observed spectra of Wolf-Rayet bubbles. They suggest that X-ray nebulae around massive stars may not be easily detectable, consistent with observations.∗
WR Time Series Photometry
(2015)
We take a comprehensive look at Wolf Rayet photometric variability using the MOST satellite. This sample, consisting of 6 WR stars and 6 WC stars defies all typical photometric analysis. We do, however, confirm the presence of unusual periodic signals resembling sawtooth waves which are present in 11 out of 12 stars in this sample.
For some years now, spectroscopic measurements of massive stars in the amateur domain have been fulfilling professional requirements. Various groups in the northern and southern hemispheres have been established, running successful professional-amateur (ProAm) collaborative campaigns, e.g., on WR, O and B type stars. Today high quality data (echelle and long-slit) are regularly delivered and corresponding results published. Night-to-night long-term observations over months to years open a new opportunity for massive-star research. We introduce recent and ongoing sample campaigns (e.g. ∊ Aur, WR 134, ζ Pup), show respective results and highlight the vast amount of data collected in various data bases. Ultimately it is in the time-dependent domain where amateurs can shine most.
Diversity is a term that is broadly used and challenging for informatics research, development and education. Diversity concerns may relate to unequal participation, knowledge and methodology, curricula, institutional planning etc. For a lot of these areas, measures, guidelines and best practices on diversity awareness exist. A systemic, sustainable impact of diversity measures on informatics is still largely missing. In this paper I explore what working with diversity and gender concepts in informatics entails, what the main challenges are and provide thoughts for improvement. The paper includes definitions of diversity and intersectionality, reflections on the disciplinary basis of informatics and practical implications of integrating diversity in informatics research and development. In the final part, two concepts from the social sciences and the humanities, the notion of “third space”/hybridity and the notion of “feminist ethics of care”, serve as a lens to foster more sustainable ways of working with diversity in informatics.
Recent research has shown that the early lexical representations children establish in their second year of life already seem to be phonologically detailed enough to allow differentiation from very similar forms. In contrast to these findings children with specific language impairment show problems in discriminating phonologically similar word forms up to school age. In our study we investigated the question whether there would be differences in the processing of phonological details in normally developing and in children with low language performance in the second year of life. This was done by a retrospective study in which in the processing of phonological details was tested by a preferential looking experiment when the children were 19 months old. At the age of 30 months children were tested with a standardized German test of language comprehension and production (SETK2). The preferential looking data at 19 months revealed an opposite reaction pattern for the two groups: while the children scoring normally in the SETK2 increase their fixations of a pictured object only when it was named with the correct word, children with later low language performance did so only when presented with a phonologically slightly deviant mispronunciation. We suggest that this pattern does not point to a specific deficit in processing phonological information in these children but might be related to an instability of early phonological representations, and/or a generalized problem of information processing as compared to typically developing children.
In this review, I discuss the suitability of massive star progenitors, evolved in isolation or in interacting binaries, for the production of observed supernovae (SNe) IIb, Ib, Ic. These SN types can be explained through variations in composition. The critical need of non-thermal effects to produce He I lines favours low-mass He-rich ejecta (in which ^56 Ni can be more easily mixed with He) for the production of SNe IIb/Ib, which thus may arise preferentially from moderate-mass donors in interacting binaries. SNe Ic may instead arise from higher mass progenitors, He-poor or not, because their larger CO cores prevent efficient non-thermal excitation of He i lines. However, current single star evolution models tend to produce Wolf-Rayet (WR) stars at death that have a final mass of > 10 M⊙. Single WR star explosion models produce ejecta that are too massive to match the observed light curve widths and rise times of SNe IIb/Ib/Ic, unless their kinetic energy is systematically and far greater than the canonical value of 10^56 erg. Future work is needed to evaluate the energy/mass degeneracy in light curve properties. Alternatively, a greater mass loss during the WR phase, perhaps in the form of eruptions, as evidenced in SNe Ibn, may reduce the final WR mass. If viable, such explosions would nonetheless favour a SN Ic, not a Ib.
Wolf-Rayet (WR) stars, as they are advanced stages of the life of massive stars, provide a good test for various physical processes involved in the modelling of massive stars, such as rotation and mass loss. In this paper, we show the outputs of the latest grids of single massive stars computed with the Geneva stellar evolution code, and compare them with some observations. We present a short discussion on the shortcomings of single stars models and we also briefly discuss the impact of binarity on the WR populations.
I review our current understanding of the interaction between a Wolf-Rayet star's fast wind and the surrounding medium, and discuss to what extent the predictions of numerical simulations coincide with multiwavelength observations of Wolf-Rayet nebulae. Through a series of examples, I illustrate how changing the input physics affects the results of the numerical simulations. Finally, I discuss how numerical simulations together with multiwavelength observations of these objects allow us to unpick the previous mass-loss history of massive stars.
An overview of the known Wolf-Rayet (WR) population of the Milky Way is presented, including a brief overview of historical catalogues and recent advances based on infrared photometric and spectroscopic observations resulting in the current census of 642 (vl.13 online catalogue). The observed distribution of WR stars is considered with respect to known star clusters, given that ≤20% of WR stars in the disk are located in clusters. WN stars outnumber WC stars at all galactocentric radii, while early-type WC stars are strongly biased against the inner Milky Way. Finally, recent estimates of the global WR population in the Milky Way are reassessed, with 1,200±100 estimated, such that the current census may be 50% complete. A characteristic WR lifetime of 0.25 Myr is inferred for an initial mass threshold of 25 M⊙.
Ismar Elbogen (1874–1943) and Franz Rosenzweig (1886-1929) were both pioneers in Jewish thought and culture. Elbogen authored the most comprehensive study on Jewish liturgy, while Rosenzweig’s magnum opus The Star of Redemption has emerged as one of the twentieth century’s most innovative and elusive works of Jewish thought. Even though Rosenzweig is not known for his work on or appreciation for the Wissenschaft des Judentums, this article will explore this overlooked aspect of his thought by exploring the influence of Ismar Elbogen. Commentaries to Rosenzweig’s views on prayer are numerous, yet none mention the work of Elbogen. This is a problem. By comparing Elbogen’s work on Jewish liturgy with Rosenzweig’s writings on prayer in the Star, we are able to demonstrate how methods seminal to the Wissenschaft des Judentums helped articulate several of Rosenzweig’s most innovative contributions to Jewish thought.
Luminous Blue Variables show strong changes in their stellar wind on time scales of typically years to decades when they expand and contract radially at approximately constant luminosity. Micro-variability on shorter time scales and amplitudes can be observed superimposed to the larger scale radial changes. I will show long-term time series of high resolution spectra which we have collected in the past 20 years for many of the well known LBVs together with a few time series of weekly sampling (HR Car, R40, R71, R110, R127, S Dor) covering a time windows of up to a few months. Wind variability is seen on short and intermediate time scales with the line profiles changing from P Cygni to inverse P Cygni and double peeked profiles sometimes for the same star and spectral line. On longer time scales the ionisation levels for all chemical elements change drastically due to the strong change of the temperature on the stellar surface. While on the long term the characteristic radial changes may have impact on the over all mass loss rates, the variabilities and asymmetries on short and intermediate time scales may cause false estimates of the mass loss rates when confronting models with the observed line profiles
The most massive stars are those with the shortest but most active life. One group of massive stars, the Luminous Blue Variables (LBVs), of which only a few objects are known, are in particular of interest concerning the stability of stars. They have a high mass loss rate and are close to being instable. This is even more likely as rotation becomes an important factor in stellar evolution of these stars. Through massive stellar winds and sometimes giant eruptions, LBV nebulae are formed. Various aspects in the evolution in the LBV phase lead, beside the large scale morphological and kinematical differences, to a diversity of small structures like clumps, rims, and outflows in these nebulae.
We discuss the results of time-resolved spectroscopy of three presumably single Population I Wolf-Rayet stars in the Small Magellanic Cloud, where the ambient metallicity is $\sim 1/5 Z_\odot$. We were able to detect and follow numerous small-scale wind-embedded inhomogeneities in all observed stars. The general properties of the moving features, such as their velocity dispersions, emissivities and average accelerations, closely match the corresponding characteristics of small-scale inhomogeneities in the winds of Galactic Wolf-Rayet stars.
The influence of the wind to the total continuum of OB supergiants is discussed. For wind velocity distributions with β > 1.0, the wind can have strong influence to the total continuum emission, even at optical wavelengths. Comparing the continuum emission of clumped and unclumped winds, especially for stars with high β values, delivers flux differences of up to 30% with maximum in the near-IR. Continuum observations at these wavelengths are therefore an ideal tool to discriminate between clumped and unclumped winds of OB supergiants.
Clustering in education is important in identifying groups of objects in order to find linked patterns of correlations in educational datasets. As such, MOOCs provide a rich source of educational datasets which enable a wide selection of options to carry out clustering and an opportunity for cohort analyses. In this experience paper, five research studies on clustering in MOOCs are reviewed, drawing out several reasonings, methods, and students’ clusters that reflect certain kinds of learning behaviours. The collection of the varied clusters shows that each study identifies and defines clusters according to distinctive engagement patterns. Implications and a summary are provided at the end of the paper.
A survey has been carried out in the Computer Science (CS) department at the University of Baghdad to investigate the attitudes of CS students in a female dominant environment, showing the differences between male and female students in different academic years. We also compare the attitudes of the freshman students of two different cultures (University of Baghdad, Iraq, and the University of Potsdam).