470 research outputs found
On the stability of weight spaces of enveloping algebra in prime characteristic
By the result of Dixmier, any weight space of enveloping algebra of Lie
algebra L over a field of characteristic 0 is adL stable. In this paper we will
show that this result need not be true, if F is replaced by a field of prime
characteristic. A condition will be given, so a weight space will be adL
stable
Algebraic families of subfields in division rings
We describe relations between maximal subfields in a division ring and in its
rational extensions. More precisely, we prove that properties such as being
Galois or purely inseparable over the centre generically carry over from one to
another. We provide an application to enveloping skewfields in positive
characteristics. Namely, there always exist two maximal subfields of the
enveloping skewfield of a solvable Lie algebra, such that one is Galois and the
second purely inseparable of exponent 1 over the centre. This extends results
of Schue in the restricted case. Along the way we provide a description of the
enveloping algebra of the p-envelope of a Lie algebra as a polynomial extension
of the smaller enveloping algebra.Comment: 9 pages, revised according to referee comments, new titl
Children's sleep, health and behaviour
Käesoleva uurimustöö eesmärk oli uurida lasteaedade lapsi – kuidas nende päevase uinaku pikkus ja kvaliteet on seotud ööune pikkuse ja kvaliteediga ning kuidas mõlemad on seotud tervise- ja käitumisprobleemidega. Valim koosnes 112st Tartu linna ja maakonna lapsest. Uuring oli küsimustikupõhine. Lapse kohta täitsid küsimustikud nii uuritava lapse vanemad kui lasteaia rühma õpetajad. Uuringu tulemused aitavad kaardistada päeva- ja ööune mustrite seoseid probleemsete valdkondadega, mis annavad aluse täpsemateks ja mahukamateks uuringuteks. Tulemused ei näidanud statistiliselt olulisi seoseid lõuna- ja ööune vahel. Küll aga oli lühem ööuni ema hinnangul seotud kehvema tervisega, rohkemate valude ja negatiivse meeleoluga. Vanusega laste vastandlik käitumine küll vähenes, kuid rohkem vastandlikku käitumist oli seotud ka lühema lõunaunega. Käitumisprobleemid olid seotud ka uneprobleemidega üldiselt
The Weberian Concept of “Labor Constitution”: The Recent Case of Delivery Workers
The concept of Arbeitsverfassung labor Constitution was developed by Max Weber early in his career when he was considered a specialist in agrarian affairs 1 that is between 1891 and 18962 In his early works this concept is tied to social organization Historically it dates back to the transition from working conditions under slavery to capitalistic forms of work In this paper I will first describe the emergence of Weber s concept of Arbeitsverfassung and how he used it in the context of his analysis of the labor situation of agricultural workers in the cases of Germany east of the Elbe River specifically and in the province of Entre R os in the Argentine Mesopotamia I will then compare the cases Weber analyzes with a contemporary empirical case based on ongoing research on the concepts of freedom work and alienation among delivery workers So this paper is organized as follows In section two I will provide a fairly detailed account of the concept Weber discovered and developed through his observation I will then briefly discuss some of the theoretical relationships between the concepts of alienation work and freedom section three Section four will apply those concepts to the current neoliberal global context of flexibilization of labor relations Section five will take that application even further looking at the figure of the platform worker as expression of the self-entrepreneu
Otthein Rammstedt and the Bliss of Sociability
Early one morning in fall of 2002, I met Otthein Rammstedt and Angela Rammstedt at the Buenos Aires airport. In the evening, I picked them up at their hotel, and we walked a few blocks before going into a bar. Professor Rammstedt ordered us each a Campari and orange juice (one part Campari to three parts juice, the formula—he explained—used in many Italian cities for evening aperitifs). From the moment the drinks came until well after midnight, we talked nonstop about Simmel. For the most part, I asked questions and Rammstedt provided generous and thorough responses, sometimes with the encouragement of Angela. Our conversation began with Simmel’s travels in Italy, and then his essay on the experience of sharing spiritual meals and drinks1 . It continued with possible Spanish-language editions of Simmel’s works, and culminated with the idea of doing a sociological study of the current Cuban embargo according to Simmel’s theory of conflict...Fil: Vernik, Esteban Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones "Gino Germani"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Carrera de Sociología; Argentina. Universidad Nacional de la Patagonia Austral; Argentin
Nations, imperialism and the circulation of the secret: some reflections on the Snowden case
O episódio ao qual irei me referir deve ser considerado por alguns ângulos particularmente interessantes: 1) o segredo e as sociedades secretas, e 2) as nações e as formas atuais de imperialismo, este último no sentido geral de intervenção de um país na soberania do outro.Fil: Vernik, Esteban Jorge. Universidad Nacional de la Patagonia; Argentina. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Stocator: A High Performance Object Store Connector for Spark
We present Stocator, a high performance object store connector for Apache
Spark, that takes advantage of object store semantics. Previous connectors have
assumed file system semantics, in particular, achieving fault tolerance and
allowing speculative execution by creating temporary files to avoid
interference between worker threads executing the same task and then renaming
these files. Rename is not a native object store operation; not only is it not
atomic, but it is implemented using a costly copy operation and a delete.
Instead our connector leverages the inherent atomicity of object creation, and
by avoiding the rename paradigm it greatly decreases the number of operations
on the object store as well as enabling a much simpler approach to dealing with
the eventually consistent semantics typical of object stores. We have
implemented Stocator and shared it in open source. Performance testing shows
that it is as much as 18 times faster for write intensive workloads and
performs as much as 30 times fewer operations on the object store than the
legacy Hadoop connectors, reducing costs both for the client and the object
storage service provider
Ultra-Low-Power Superconductor Logic
We have developed a new superconducting digital technology, Reciprocal
Quantum Logic, that uses AC power carried on a transmission line, which also
serves as a clock. Using simple experiments we have demonstrated zero static
power dissipation, thermally limited dynamic power dissipation, high clock
stability, high operating margins and low BER. These features indicate that the
technology is scalable to far more complex circuits at a significant level of
integration. On the system level, Reciprocal Quantum Logic combines the high
speed and low-power signal levels of Single-Flux- Quantum signals with the
design methodology of CMOS, including low static power dissipation, low latency
combinational logic, and efficient device count.Comment: 7 pages, 5 figure
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