92 research outputs found
Plasma assisted fabrication of zinc oxide based nanostructures
ZnO/Ag nanocomposite structures were prepared by using a discharge with an atmospheric-pressure mi-croplasma cathode and a solid metal anode immersed in an electrolyte solution and their properties were studied. The effect of Ag on the microstructure and optical properties of ZnO has been discussed
Exploring the use of 25 leading business practices in transitioning market supply chains
Purpose - In the global economy, managers of organizations are constantly innovating with their use of available supply chain management tools. Some tools, like strategic planning and customer segmentation, have gained strong global acceptance while others are less universal. In this study, we focus our contribution on the organizational factors that predict firm usage of supply chain management tools in two Eastern Europe countries, Slovenia and Croatia, while also comparing them to the global use of similar management tools. Design/methodology/approach - This research provides an empirical analysis of supply chain management tool usage from a survey of 155 firms in Slovenia and 185 firms in Croatia while also comparing these findings to results from a global Bain & Company survey. Findings - The 25 most commonly used supply chain management tools in our Eastern European survey were found to be relatively similar to those used across Europe and North America. However, further analysis of five selected tools reveals important differences. Evidence is found to support that particular organizational factors have a significant influence on supply chain management tool usage, of specific importance is the education level of the organization manager. Research limitations/implications - The research study is limited to the research question, selective literature review, and survey sample from Eastern Europe. Practical implications - As firms assess their supply chain management tool usage, the findings presented here might serve as a guide to improve their understanding of why organization managers employ particular tools more consistently than others. Originality/value - The findings are useful for business practice in understanding the influences of organizational factors on supply chain management tool usage. Also, the research is original as previous management literature has not provided a similar approach to researching management tools and their usage
Poincar\'e recurrence theorem and the strong CP-problem
The existence in the physical QCD vacuum of nonzero gluon condensates, such
as , requires dominance of gluon fields with finite mean action
density. This naturally allows any real number value for the unit ``topological
charge'' characterising the fields approximating the gluon configurations
which should dominate the QCD partition function. If is an irrational
number then the critical values of the parameter for which CP is
spontaneously broken are dense in , which provides for a mechanism
of resolving the strong CP problem simultaneously with a correct implementation
of symmetry. We present an explicit realisation of this
mechanism within a QCD motivated domain model. Some model independent arguments
are given that suggest the relevance of this mechanism also to genuine QCD.Comment: 8 pages, RevTeX, 3 figures. Revised after referee suggestions. Now
includes model independent argument
Spectral density in resonance region and analytic confinement
We study the role of finite widths of resonances in a nonlocal version of the
Wick-Cutkosky model. The spectrum of bound states is known analytically in this
model and forms linear Regge tragectories. We compute the widths of resonances,
calculate the spectral density in an extension of the Breit-Wigner {\it ansatz}
and discuss a mechanism for the damping of unphysical exponential growth of
observables at high energy due to finite widths of resonances.Comment: 13 pages, RevTeX, 6 figures. Revised version with typographical
corrections and additional comments in conclusion
Impact of the strong electromagnetic field on the QCD effective potential for homogeneous Abelian gluon field configurations
The one-loop quark contribution to the QCD effective potential for the
homogeneous Abelian gluon field in the presence of external strong
electromagnetic field is evaluated. The structure of extrema of the potential
as a function of the angles between chromoelectric, chromomagnetic and
electromagnetic fields is analyzed. In this setup, the electromagnetic field is
considered as an external one while the gluon field represents domain
structured nonperturbative gluon configurations related to the QCD vacuum in
the confinement phase. Two particularly interesting gluon configurations,
(anti-)self-dual and crossed orthogonal chromomagnetic and chromoelectric
fields, are discussed specifically. Within this simplified framework it is
shown that the strong electromagnetic fields can play a catalysing role for a
deconfinement transition. At the qualitative level, the present consideration
can be seen as a highly simplified study of an impact of the electromagnetic
fields generated in relativistic heavy ion collisions on the strongly
interacting hadronic matter.Comment: 9 pages, 4 figure
Weyl group, CP and the kink-like field configurations in the effective SU(3) gauge theory
Effective Lagrangian for pure Yang-Mills gauge fields invariant under the
standard space-time and local gauge SU(3) transformations is considered. It is
demonstrated that a set of twelve degenerated minima exists as soon as a
nonzero gluon condensate is postulated. The minima are connected to each other
by the parity transformations and Weyl group transformations associated with
the color su(3) algebra. The presence of degenerated discrete minima in the
effective potential leads to the solutions of the effective Euclidean equations
of motion in the form of the kink-like gauge field configurations interpolating
between different minima. Spectrum of charged scalar field in the kink
background is discussed.Comment: 10 pages, 1 figure, added references for sections 1 and
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