Group algebras whose group of units is powerful

A p-group is called powerful if every commutator is a product of pth powers when p is odd and a product of fourth powers when p=2. In the group algebra of a group G of p-power order over a finite field of characteristic p, the group of normalized units is always a p-group. We prove that it is never powerful except, of course, when G is abelian.Comment: 4 page

Completely simple endomorphism rings of modules

[EN] It is proved that if Ap is a countable elementary abelian p-group, then: (i) The ring End (Ap) does not admit a nondiscrete locally compact ring topology. (ii) Under (CH) the simple ring End (Ap)/I, where I is the ideal of End (Ap) consisting of all endomorphisms with finite images, does not admit a nondiscrete locally compact ring topology. (iii) The finite topology on End (Ap) is the only second metrizable ring topology on it. Moreover, a characterization of completely simple endomorphism rings of modules over commutative rings is obtained.Supported by UAEU UPAR (9) 2017 Grant G00002599.Bovdi, V.; Salim, M.; Ursul, M. (2018). Completely simple endomorphism rings of modules. Applied General Topology. 19(2):223-237. https://doi.org/10.4995/agt.2018.7955SWORD223237192A. V. Arkhangelskii and V. I. Ponomarev, Osnovy obshchei topologii v zadachakh i uprazhneniyakh, Izdat. Nauka, Moscow, 1974.V. I. Arnautov, S. T. Glavatsky and A. V. Mikhalev, Introduction to the theory of topological rings and modules, vol. 197 of Monographs and Textbooks in Pure and Applied Mathematics. Marcel Dekker, Inc., New York, 1996.V. I. Arnautov and M. I. Ursul, Uniqueness of a linearly compact topology in rings, Mat. Issled. 53 (1979), 6-14, 221.N. Bourbaki, Kommutativnaya algebra, Izdat. Mir, Moscow, 1971. Èlementy Matematiki, Vyp. XXVII, XXVIII, XXX, XXXI. [Foundations of Mathematics, No. XXVII, XXVIII, XXX, XXXI], Translated from the French by A. A. Belskii, Edited by E. S. Golod.N. Bourbaki, General topology. Chapters 1-4. Elements of Mathematics (Berlin), Springer-Verlag, Berlin, 1998.N. Bourbaki, Obshchaya topologiya. Izdat. Nauka, Moscow, 1975. Ispolzovanie veshchestvennykh chisel v obshchei topologii. Funktsionalnye prostranstva. Svodka rezultatov. Slovar. [Application of real numbers in general topology. Functional spaces. Resumé of results. Vocabulary], Translated from the third French edition by S. N. Krackovskii, Edited by D. A. Raikov.D. Dikranjan, Minimal topological rings, Serdica 8, no. 2 (1982), 149-165.R. Engelking, General topology, vol. 6 of Sigma Series in Pure Mathematics. Heldermann Verlag, Berlin, ii ed., 1989.H. Freudenthal, Einige sätze über topologische gruppen, Ann. of Math. (2) 37, no. 1 (1936), 46-56. 1936.E. D. Gaughan, Topological group structures of infinite symmetric groups, Proc. Nat. Acad. Sci. U.S.A. 58 (1967), 907-910. https://doi.org/10.1073/pnas.58.3.907M. I. Graev, Theory of topological groups. I. Norms and metrics on groups. Complete groups. Free topological groups, Uspehi Matem. Nauk (N.S.) 5, no. 2 (36) (1950), 3-56.E. Hewitt and K. A. Ross, Abstract harmonic analysis. Vol. I, vol. 115 of Grundlehren der Mathematischen Wissenschaften [Fundamental Principles of Mathematical Sciences]. Springer-Verlag, Berlin-New York, second ed., 1979. https://doi.org/10.1007/978-1-4419-8638-2M. Hochster and J. O. Kiltinen, Commutative rings with identity have ring topologies, Bull. Amer. Math. Soc. 76 (1970), 419-420. https://doi.org/10.1090/S0002-9904-1970-12495-8A. Hulanicki, On locally compact topological groups of power of continuum, Fund. Math. 44 (1957), 156-158. https://doi.org/10.4064/fm-44-2-156-158N. Jacobson, Totally disconnected locally compact rings, Amer. J. Math. 58, no. 2 (1936), 433-449. https://doi.org/10.2307/2371052N. Jacobson, A note on topological fields, Amer. J. Math. 59, no. 4 (1937), 889-894. https://doi.org/10.2307/2371355N. Jacobson, Structure of rings, American Mathematical Society, Colloquium Publications, vol. 37, American Mathematical Society, 190 Hope Street, Prov., R. I., 1956.F. B. Jones, On the first countability axiom for locally compact Hausdorff spaces, Colloq. Math. 7 (1959), 33-34. https://doi.org/10.4064/cm-7-1-33-34I. Kaplansky, Topological rings, Amer. J. Math. 69 (1947), 153-183. https://doi.org/10.2307/2371662I. Kaplansky, Selected papers and other writings, Springer Collected Works in Mathe-matics, Springer, New York, 2013.T. Y. Lam, A first course in noncommutative rings, vol. 131 of Graduate Texts in Mathematics. Springer-Verlag, New York, 1991.H. Leptin, Linear kompakte moduln und ringe, Math. Z. 62 (1955), 241-267. https://doi.org/10.1007/BF01180634R. D. Mauldin, ed., The {S}cottish {B}ook, Birkhäuser/Springer, Cham, second ed., 2015.A. F. Mutylin, Completely simple commutative topological rings, Mat. Zametki 5 (1969), 161-171. https://doi.org/10.1007/BF01098307L. S. Pontryagin, Continuous groups, Nauka, Moscow, fourth ed., 1984.L. Skornjakov, Einfache lokal bikompakte ringe, Math. Z. 87 (1965), 241-251. https://doi.org/10.1007/BF01109942M. Ursul, Topological rings satisfying compactness conditions, vol. 549 of Mathematics and its Applications. Kluwer Academic Publishers, Dordrecht, 2002.R. Ware and J. Zelmanowitz, Simple endomorphism rings, Amer. Math. 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Analisis Dampak Perubahan Arus Pengelasan Terhadap Kekuatan Sambungan Las Pada Material Stainless Steel 316

In a situation of increasing urbanization in the capital, the demand for decent and quality housing is also increasing rapidly. This increase was in line with increasing market demand for specific construction products such as railings, doors and windows which are of good quality. The research method and data collection will start from nine pairs of 316 stainless steel plates which will be welded using SMAW welding. Welding on stainless steel plates will be carried out with varying welding currents of 60 A, 70 A and 80 A. Each of these welding currents will be carried out on three stainless steel plates. The results showed that the use of a higher variation of welding current in the welding process resulted in a higher strength of the welded joint. The elastic modulus can decrease due to several factors such as the presence of microscopic cracks, changes in crystal structure, or changes in the bonds between atoms or molecules of the material. The strength of welded joints in stainless steel 316 material can also be affected by other factors besides variations in welding current. Parameters such as mains voltage, welding time and type of electrode also contribute to the strength of the welded joint

EFEKTIVITAS MEDIA PEMBELAJARAN DIGITAL KIMIA ANALISA KUALITATIF DALAM MENINGKATKAN KEMAMPUAN KOGNITIF DAN KREATIVITAS MAHASISWA DI MASA PANDEMI COVID-19

Pelaksanaan akademik salah satunya merupakan Interaksi pembelajaran dosen dengan mahasiswa, yaitu sharing knowledge materi perkuliahan yang dilaksanakan. Oleh sebab itu sangat di butuhkan media pendukung pembelajaran agar perkuliahan terlaksana secara optimal. Dimasa pandemi covid-19 saat ini media digital menjadi alternative  sebagai media pembelajaran yang relevan. Penelitian ini menyajikan data kuantitatif dan kualitatif yang diperoleh melalui quisioner dan pengujian nilai kelayakan media pembelajaran digital sesuai dengan indikator kelayakan mengacu pada Badan Standar Nasional Pendidikan (BSNP) dan untuk kuantitative diperoleh dari hasil pengujian efektifitas Efektivitas Media Pembelajaran Digital Kimia Analisa Kualitatif Dalam Meningkatkan Kemampuan Kognitif Dan Kemandirian Mahasiswa Di Masa Pandemi Covid-19. Populasi penelitian ini adalah seluruh mahasiswa program studi farmasi universitas Efarina semester II TA. 2020/2021. Perhitungan  data diperoleh dengan melakukan tes hasil kognitif mahasiswa. Data dianalisa dengan aplikasi SPSS 17.0 unuk signifikan alfa sebesar 0,05. Pengujian validasi penentuan kelayakan media pembelajaran digital diperoleh hasil: (1) Diperoleh media pembelajaran digital sesuai standar kelayakan merujuk pada Kurikulum Farmasi(2) Media pembelajaran digital hasil pengembangan susdah sesuai standard an dapat digunakan sesuai hasil standarisasi diperoleh: standar kelayakan isi sebesar 3.68, standar kelayakan bahasa sebesar 3,58, standar kelayakan penyajian sebesar 3,76, standar kegrafikaan sebesar 3,79 (3) Terdapat peningkatan yang dignifikan kemampuan hasil belajar kognitif mahasiswa dengan menggunakan media pembelajaran digital. (Sig.hitung<  α (0,0267 < 0,05)) (4) Terdapat hasil yang dignifikan peningkatan kreativitas mahasiswa dengan menggunakan media pembelajaran digital. (Sig. hitung<  α (0,0176 < 0,05))

Effect of the Mass Conversion Degree of an Oxygen Carrier on Char Conversion and Its Implication for Chemical Looping Gasification

Chemical looping gasification (CLG) is an emerging process that aims to produce valuable chemical feedstocks. The key operational requirement of CLG is to limit the oxygen transfer from the air reactor (AR) to the fuel reactor (FR). This can be accomplished by partially oxidizing the oxygen carrier in the AR, which may lead to a higher reduction degree of the oxygen carrier under the fuel conversion. A highly reduced oxygen carrier may experience multiple issues, such as agglomeration and defluidization. Given such an interest, this study examined how the variation of the mass conversion degree of ilmenite may affect the conversion of pine forest residue char in a fluidized bed batch reactor. Ilmenite was pre-reduced using diluted CO and then underwent the char conversion at 850, 900, 950, and 975 degrees C. Our investigations showed that the activation energy of the char conversion was between 194 and 256 kJ/mol, depending upon the mass conversion degree of ilmenite. Furthermore, the hydrogen partial pressure in the particle bed increased as the oxygen carrier mass conversion degree decreased, which was accompanied by a lower reaction rate and a higher reduction potential. Such a hydrogen inhibition effect was confirmed in the experiments; therefore, the change in the mass conversion degree indirectly affected the char conversion. Langmuir-Hinshelwood mechanism models used to evaluate the char conversion were validated. On the basis of the physical observation and characterizations, the use of ilmenite in CLG with biomass char as fuel will likely not suffer from major agglomeration or fluidization issues

Performance of iron sand as an oxygen carrier at high reduction degrees and its potential use for chemical looping gasification

Iron sand as an industrial by-product has a reasonable iron content (35 wt% Fe) and low economical cost. The reactivity of iron sand as an oxygen carrier was examined in a bubbling fluidized bed reactor using both gaseous and solid fuels at 850–975 \ub0C. Pre-reductions of iron sand were performed prior to fuel conversion to adapt the less-oxygen-requiring environment in chemical looping gasification (CLG). Based on the investigations using CO and CH4, iron sand has an oxygen transfer capacity of around 1 wt%, which is lower than that of ilmenite. The conversion of pine forest residue char to CO and H2 was higher when using iron sand compared to ilmenite. Depending on the mass conversion degree of iron sand, the activation energy of pine forest residue char conversion using iron sand was between 187 and 234 kJ/mol, which is slightly lower than that of ilmenite. Neither agglomeration nor defluidization of an iron sand bed occurred even at high reduction degrees. These suggests that iron sand can be utilized as an oxygen carrier in CLG. Furthermore, this study presents novel findings in the crystalline phase transformation of iron sand at various degrees of oxidation, altogether with relevant thermodynamic stable phases

Determining Call-To-Entry Rate and Recruitment Barriers in Clinical Studies For Community Clinics Serving Low-income Populations: a Cohort Study

BACKGROUND: Recruitment for clinical studies is challenging. to overcome barriers, investigators have previously established call-to-entry rates to assist in planning. However, rates specific to low-income minority populations are needed to account for additional barriers to enrolment these individuals face. OBJECTIVE: to obtain a call-to-entry rate in a low-income uninsured Hispanic population with chronic disease. METHODS: We used data from four of our randomised clinical studies to determine the call-to-entry rate for individuals (n=1075) with or at risk for type 2 diabetes: participants needed/potential participants contacted=recruitment rate (yield). Research staff contacted potential participants to enrol in a study that evaluated 6 month diabetes programmes at community clinics from 2015 to 2020. We recorded call-to-entry rates, reasons for declining the study, show rates, and attrition. RESULTS: The call-to-entry rate was 14.5%. Forty per cent of potential participants could not be contacted, and 30.6%, 19.1%, and 5.4% responded CONCLUSIONS: We described a call-to-entry rate and detailed recruitment data, including reasons to decline the study. This valuable information can assist investigators in study planning and overcoming enrolment barriers in low-income populations. Telehealth-based or strategies that limit transportation needs may increase participant involvement. TRIAL REGISTRATION NUMBER: NCT03394456

Até que Ponto Sistemas Inteligentes Podem Tomar Decisões Sem Ferir a Ética

O vigente artigo busca explorar observações sobre a imersão da inteligência artificial no nosso cotidiano e como suas aplicações se relacionam com questões éticas. Através de um estudo empírico, este trabalho aborda a forma como as aplicações de IA no âmbito social são vistas pelo público em geral. No mais, importante observar como este público percebe a forma como os carros autônomos se envolvem em processos de tomada de decisões como também os sistemas de inteligência artificial são passíveis de herdar e propagar um viés preconceituoso presente em sua base de dados. Fazendo uso de um questionário para analisar o conhecimento das pessoas acerca do tema abordado, a fim de obter um panorama do entendimento desse público e assimilar esses resultados com as ideias dos autores estudados, além de contribuir com o debate sobre o tema. Palavras-chave: Inteligência artificial; Ética; Carros autônomos