250 research outputs found
Isomorphic and isometric structure of the optimal domains for Hardy-type operators
We investigate structure of the optimal domains for the Hardy-type operators
including, for example, the classical Ces\`aro, Copson and Volterra operators
as well as for some of their generalizations. We prove that, in some sense, the
abstract Ces\`aro and Copson function spaces are closely related to the space
, namely, they contain "in the middle" a complemented copy of ,
asymptotically isometric copy of and also can be renormed to contain
an isometric copy of . Moreover, the generalized Tandori function
spaces are quite similar to because they contain an isometric copy
of and can be renormed to contain an isometric copy of
. Several applications to the metric fixed point theory will be
given. Next, we prove that the Ces\`aro construction does not
commutate with the truncation operation of the measure space support. We also
study whether a given property transfers between a Banach function space
and the space , where is the Ces\`aro or the Copson operator. In
particular, we find a large class of properties which do not lift from
into and prove that the abstract Ces\`aro and Copson function spaces are
never reflexive, are not isomorphic to a dual space and do not have the
Radon--Nikodym property in general.Comment: 34 pages; we changed the title and added some corrections compared to
the first versio
Conformational degrees of freedom and stability of splay-bend ordering in the limit of a very strong planar anchoring
We study the self-organization of flexible planar trimer particles on a
structureless surface. The molecules are made up of two mesogenic units linked
by a spacer, all of which are modeled as hard needles of the same length. Each
molecule can dynamically adopt two conformational states: an achiral
bent-shaped (cis-) and a chiral zigzag (trans-) one.
Using constant pressure Monte Carlo simulations and Onsager-type density
functional theory (DFT), we show that the system consisting of these molecules
exhibits a rich spectrum of (quasi-)liquid crystalline phases. The most
interesting observation is the identification of stable smectic splay-bend
() and chiral smectic A () phases. The phase is also
stable in the limit, where only cis-conformers are allowed. The second phase
occupying a considerable portion of the phase diagram is with chiral
layers, where the chirality of the neighboring layers is of opposite sign. The
study of the average fractions of the trans- and cis-conformers in various
phases shows that while in the isotropic phase all fractions are equally
populated, the phase is dominated by chiral conformers (zigzag), but
the achiral conformers win in the smectic splay-bend phase. To clarify the
possibility of stabilization of the nematic splay bend () phase for
trimers, the free energy of the and phases is calculated
within DFT for the cis-conformers, for densities where simulations show stable
. It turns out that the phase is unstable away from the phase
transition to the nematic phase, and its free energy is always higher than that
of , down to the transition to the nematic phase, although the
difference in free energies becomes extremely small when approaching the
transition
Sphinx: Monte Carlo Program for Polarised Nucleon-Nucleon Collisions
This program can be used to simulate polarised nucleon - nucleon collisions
at high energies. Spins of colliding particles are taken into account. The
program allows to calculate cross sections for various processes.Comment: 33pp, LaTe
Phenomenology of diphoton photoproduction at next-to-leading order
We develop the analysis of diphoton exclusive photoproduction in the
kinematics where a collinear QCD factorization framework applies, namely nearly
forward large invariant mass diphoton production. We work at the leading twist
level and at the next-to-leading order (NLO) in the strong coupling constant
. We compare our predictions for cross-sections with Born order
calculations for the experimental conditions accessible to JLab experiments and
show the interesting sensitivity of our results to various models of
generalized parton distributions (GPDs). The NLO corrections are rather large
and negative but do not prevent the studied reaction from being a promising
tool for the extraction of C-dd GPDs, which do not contribute to either
spacelike or timelike deeply virtual Compton scattering amplitudes
Creating reliable and resilient logistics organizations for unpredictable conditions and unexpected future
PURPOSE: The objective of this paper is to develop a general concept for creating resilient
logistics organizations under the deep uncertainty that arises from unpredictable conditions
and unexpected future, and to integrate it with a framework for ensuring the reliable operation
of these organizations under conditions of predictable change.DESIGN/METHODOLOGY/APPROACH: The research methodology was based on a transdisciplinary
approach because logistics organizations have the nature of complex systems with different
types of systems such as physical, cybernetic and social ones. The research approach used is
based on a critical analysis of the literature and case studies from the authors' own experience.
The research is supported by Ackoff's 'idealized design' approach and assumptions from The
IRGC Risk Governance Framework.FINDINGS: It was found that complex logistics organizations can be successfully modelled as
Engineered System of Systems and managed according to the principles applicable to such
systems. Furthermore, it was shown that it is possible to combine two different concepts,
namely High Reliability Organization and Resilient Enterprise, into one coherent whole in the
form of a Reliable and Resilient Logistics Organization.PRACTICAL IMPLICATIONS: For practical use of the developed concept, a framework was designed
in the form of an algorithm describing the process of creating Reliable and Resilient Logistics
Organization in the form of successive stages of action and decisions.ORIGINALITY/VALUE: The concept of the Reliable and Resilient Logistics Organization is wholly
original and is the result of many years of our research into the behavior of complex sociotechnical systems under uncertainty. The added value of the work is the model developed,
which in the form of a framework can be used in practice in logistics organizations to ensure
their continuous and effective operation under various conditions, both predictable and
unpredictable changes in the environment.The project is funded under the program of the Minister of Science and
Higher Education titled “Regional Initiative of Excellence” in 2019-2022, project number
018/RID/2018/19, the amount of funding PLN 10 788 423,16.peer-reviewe
Collectivist logic in comparative genocide studies and in the battles for memory
The article aims to present the mechanisms of collectivist logic as it functions in
three areas: (1) in the historical comparative analysis of genocides – the basic method of genocide
studies; (2) in the activities of the organizations of victims and survivors, as well as in actions
undertaken by animal rights activists; (3) in nationalist discourses and in the politics of memory.
Collectivist logic is a set of operations that address human communities – groups of individuals
linked together by significant social bonds and interests, and perceived as culturally distinctive –
as the subject of history. As a result of the application of such logic, we may think about collective
guilt and collective merit. The article discusses the advantages and disadvantages of historical
comparative analysis as an essential methodological tool of genocide studies. The argument
further focuses upon the use of the symbolic capital attributed to the term “genocide” in studies
involving analyses comparing other crimes – as well as the industrial exploitation of animals –
to genocides. Finally, the author describes the relationship between the state policy of memory,
nationalist discourses, and the academic integrity of genocide scholars
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