• Title/Summary/Keyword: Leibniz

Search Result 94, Processing Time 0.049 seconds

Leibniz Crossing Borders (탈경 계인' 라이프니츠)

  • Park, Chang-Kyun
    • Journal for History of Mathematics
    • /
    • v.21 no.4
    • /
    • pp.49-60
    • /
    • 2008
  • When a man is called a person crossing borders(PCB), he is a man who pursues communication, coexistence and combination beyond visible and/or invisible borders of nations and disciplinaries. This paper examines Leibniz as a PCB in his life and learning, and how his metaphysics, the pre-established harmony, enabled him to be a PCB.

  • PDF

RELATIVE ROTA-BAXTER SYSTEMS ON LEIBNIZ ALGEBRAS

  • Apurba Das;Shuangjian Guo
    • Journal of the Korean Mathematical Society
    • /
    • v.60 no.2
    • /
    • pp.303-325
    • /
    • 2023
  • In this paper, we introduce relative Rota-Baxter systems on Leibniz algebras and give some characterizations and new constructions. Then we construct a graded Lie algebra whose Maurer-Cartan elements are relative Rota-Baxter systems. This allows us to define a cohomology theory associated with a relative Rota-Baxter system. Finally, we study formal deformations and extendibility of finite order deformations of a relative Rota-Baxter system in terms of the cohomology theory.

Probabilistic vibration and lifetime analysis of regenerated turbomachinery blades

  • Berger, Ricarda;Rogge, Timo;Jansen, Eelco;Rolfes, Raimund
    • Advances in aircraft and spacecraft science
    • /
    • v.3 no.4
    • /
    • pp.503-521
    • /
    • 2016
  • Variances in turbomachinery blades caused by manufacturing, operation or regeneration can result in modified structural behavior. In this work, the scatter of geometrical and material properties of a turbine blade and its influence on structure performance is discussed. In particular, the vibration characteristics and the lifetime of a turbine blade are evaluated. Geometrical variances of the surface of the blades are described using the principal component analysis. The scatter in material properties is considered by 16 varying material parameters. Maximum vibration amplitudes and the number of load cycles the turbine blade can withstand are analyzed by finite element simulations incorporating probabilistic principles. The probabilistic simulations demonstrate that both geometrical and material variances have a significant influence on the scatter of vibration amplitude and lifetime. Dependencies are quantified and correlations between varied input parameters and the structural performance of the blade are detected.

Nanostructure formation in thin films of block copolymers prepared by controlled radical polymerization

  • Voit, B.;Fleischmann, S.;Messerschmidt, M.;Leuteritz, A.
    • Proceedings of the Polymer Society of Korea Conference
    • /
    • 2006.10a
    • /
    • pp.99-100
    • /
    • 2006
  • Orthogonally protected block copolymers of based on p-hydroxystyrene were prepared with high control via nitroxy mediated radical polymerization using an alkoxyamine as an unimolecular initiator. Thin films of partially protected block copolymer were prepared by spin or dip coating. A well defined nanostructure could be observed as a result of phase separation e.g. cylinders in a matrix oriented perpendicular or parallel to the substrate. The nanostructure of the polymeric films can be defined by the block copolymer composition and it determines surface properties and allows further, selective functionalization, e.g. via click chemistry. The thin films can be designed in a way to allow a patterning based on a thermal or photochemical stimulus.

  • PDF

Quantitative Review of Oral Cancer Research Output from Pakistan

  • Khan, Zohaib;Muller, Steffen;Ahmed, Shahzad;Tonnies, Justus;Nadir, Faryal;Samkange-Zeeb, Florence
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.11
    • /
    • pp.4733-4739
    • /
    • 2015
  • Background: Oral cancer is the most common cancer among men and second only to breast cancer among women in Pakistan. For the effective control and prevention of oral cancer, Pakistan needs to recognize the importance of research and generation of the evidence-base which can inform policy making and planning and implementation of intervention programs. The objective of this review was to quantify oral cancer research output in Pakistan. Materials and Methods: A systematic electronic search in "Medline", "ISI-Web of Science" and "Pakmedinet", supplemented by a Google search, was carried out in January and February, 2014, to identify literature from Pakistan relevant to oral cancer. The selection of publications for the review was carried out according to preset criteria. Data were recorded and analyzed using Microsoft Excel. Results: A total of 166 publications comprising 62 case series, 36 cross sectional, 31 case control, 10 basic laboratory research, eleven reviews and two trials, were included in this review. Some 35 % of the publications focused on risk factors for oral cancer. COMSATS Institute of Information Technology was the institution with the highest contribution. Conclusions: There is a lack of research in the field of oral cancer research in Pakistan. Focused efforts should be put in place to improve both quality and quantity of oral cancer research in the country.

Argument Structure of Leibniz's Theodicy (라이프니츠 변신론의 논증 구조)

  • Lee, Nam-won
    • Journal of Korean Philosophical Society
    • /
    • v.131
    • /
    • pp.273-301
    • /
    • 2014
  • This study aims to reconstruct Leibniz's theodicy. Theodicy is to defense of the highest wisdom of the creator against the charge which reason brings against it for whatever is the evil in the world. For this defense, Leibniz created his own new kind of concepts: the principle of sufficient reason, the principle of perfection, the best of all possible worlds, moral necessity. Leibniz's theodicy is developed as following. Most good and wisest God created this world freely by moral necessity. God's will was to choose the goods antecedently. But God's will could not create goods only. For God's final purpose is to create the best. For this reason, it happens that the evils may come about by concomitance, and as a result of other greater goods. Therefore the evils are necessary in the world. And evil consists in imperfection. Man has free will as God. Freedom, according to Leibniz, consists in intelligence, which involves a clear knowledge of the object of deliberation. Man has freedom, but man's freedom is imperfect. Evil is originated in man's imperfect freedom.

Properties of polypropylene fibers using the green chemical orotic acid as nucleating agent

  • Vogel, Roland;Brunig, Harald;Haussler, Liane
    • Advances in materials Research
    • /
    • v.4 no.4
    • /
    • pp.207-214
    • /
    • 2015
  • It has been reported in the technical literature that orotic acid can be used in order to induce improved crystallization of biodegradable and biocompatible polymers like poly(L-lactic acid), polyhydroxybutyrate and poly(hydroxybutyrate-co-hydroxyhexaonat). The expected advantage of the changed crystalline structure is a reinforcing effect of the polymers. A lot of papers reported about the application of inorganic and organic agents for acceleration of heterogeneous nucleation. This study reports on an attempt to use orotic acid as appropriate non-toxic nucleating agent for improving mechanical properties of isotactic polypropylene. Special attention is given to demonstrate the effect of nucleation in a typical melt spinning process in order to improve the mechanical properties. The effects were demonstrated using rheology, thermal analysis and tensile testing.

A REMARK ON THE CONJUGATION IN THE STEENROD ALGEBRA

  • TURGAY, NESET DENIZ
    • Communications of the Korean Mathematical Society
    • /
    • v.30 no.3
    • /
    • pp.269-276
    • /
    • 2015
  • We investigate the Hopf algebra conjugation, ${\chi}$, of the mod 2 Steenrod algebra, $\mathcal{A}_2$, in terms of the Hopf algebra conjugation, ${\chi}^{\prime}$, of the mod 2 Leibniz-Hopf algebra. We also investigate the fixed points of $\mathcal{A}_2$ under ${\chi}$ and their relationship to the invariants under ${\chi}^{\prime}$.

FURTHER EXPANSION AND SUMMATION FORMULAS INVOLVING THE HYPERHARMONIC FUNCTION

  • Gaboury, Sebastien
    • Communications of the Korean Mathematical Society
    • /
    • v.29 no.2
    • /
    • pp.269-283
    • /
    • 2014
  • The aim of the paper is to present several new relationships involving the hyperharmonic function introduced by Mez$\ddot{o}$ in (I. Mez$\ddot{o}$, Analytic extension of hyperharmonic numbers, Online J. Anal. Comb. 4, 2009) which is an analytic extension of the hyperharmonic numbers. These relations are obtained by using some fractional calculus theorems as Leibniz rules and Taylor like series expansions.