1,897 research outputs found
Extraction of the proton charge radius from experiments
Static properties of hadrons such as their radii and other moments of the
electric and magnetic distributions can only be extracted using theoretical
methods and not directly measured from experiments. As a result, discrepancies
between the extracted values from different precision measurements can exist.
The proton charge radius, , which is either extracted from electron proton
elastic scattering data or from hydrogen atom spectroscopy seems to be no
exception. The value fm extracted from muonic hydrogen
spectroscopy is about 4% smaller than that obtained from electron proton
scattering or standard hydrogen spectroscopy. The resolution of this so called
proton radius puzzle has been attempted in many different ways over the past
six years. The present article reviews these attempts with a focus on the
methods of extracting the radius.Comment: Mini review, 14 pages, 1 figur
Deontological considerations on academic collaboration in Poland
The author conducted deontological deliberations concerning collaboration
among academic workers in the reality of Polish universities. In the view of potential
irregularities that threaten this cooperation, it has been investigated what answer is
brought in this regard by the ethical codes of universities but also how this problem is
perceived by the students who tend to be critical and keen observers. As far as
codification is concerned of standards related to the issue in question, Polish academic
environment is not in a bad condition. It seems that the problem has been noticed.
However, when those documents are perceived as a collection of not so much written, but rather actually recognized values, then the quoted remarks of the students would prove that there is more work to be performed in this respect, which should be deepened under
studies of quantitative and qualitative nature. One clear conclusion is drawn from the
performed analyses. Namely undermining the authority of one academic by another - in
particular in the eyes of the students - results not only in weakening the authority of the
humiliated person but mainly of the humiliating individual. Moreover, it contributes to
straining the authority of an academic as such
Przeciwdziałanie mobbingowi w Służbie Więziennej w Polsce
The paper deals with the problem of workplace mobbing in the Polish Prison Service. The introduction points out to the multifaceted character of mobbing behaviours. It also mentions their harmful effect on the victim’s personal, family and professional life. Further on, the issue is analysed from the perspective of the Polish labour law by reference to relevant provisions on these matters. Then, the basic issue of the paper is discussed, i.e. mobbing among prison personnel, pointing out that uniformed services are an emanation of the society and can be affected by the same phenomena, including negative ones. To this end, the procedures that are in force in the Prison Service with regard to reacting to mobbing behaviours are described; also, light is cast on appropriate preventing measures, including trainings for management staff, officers, and other personnel of correctional facilities. Finally, reference is made to the criticism formulated against the abovementioned procedures and relevant recommendations are presented, mentioning that counteracting mobbing should take place within the scope of internal regulations of the institution, the practice of management, and the accepted ethics and culture.W artykule podjęto problem mobbingu w Służbie Więziennej w Polsce. We wstępie wskazano na wieloaspektowy charakter zachowań mobbingowych. Zasygnalizowano ich szkodliwy wpływ na życie osobiste, rodzinne i zawodowe ofiary oraz przeanalizowano zagadnienie z perspektywy polskiego prawa pracy, odwołując się do stosownych zapisów. Następnie przystąpiono do omówienia mobbingu wśród personelu zakładów penitencjarnych, wskazując, że służby mundurowe stanowią emanację społeczeństwa i mogą w nich występować identyczne zjawiska, włącznie z negatywnymi. W związku z tym opisano obowiązujące w Służbie Więziennej procedury dotyczące reagowania na zachowania mobbingowe oraz naświetlono adekwatne działania profilaktyczne, m.in. szkolenia dla kadry kierowniczej, funkcjonariuszy i pozostałych członków personelu zakładów penitencjarnych. Na koniec przywołano zarzuty formułowane w stosunku do wyżej wspomnianych procedur oraz przedstawiono stosowne rekomendacje, podkreślając, że przeciwdziałanie mobbingowi powinno się odbywać w wymiarze prawa wewnętrznego danej instytucji, praktyki zarządzania, ale też w obszarze przyjętej etyki i kultury
Sensitivity analysis for shape perturbation of cavity or internal crack using BIE and adjoint variable approach
This paper deals with the application of the adjoint variable approach to sensitivity analysis of objective functions used for defect detection from knowledge of supplementary boundary data, in connection with the use of BIE/BEM formulations for the relevant forward problem. The main objective is to establish expressions for crack shape sensitivity, based on the adjoint variable approach, that are suitable for BEM implementation. In order to do so, it is useful to consider first the case of a cavity defect, for which such boundary-only sensitivity expressions are obtained for general initial geometry and shape perturbations. The analysis made in the cavity defect case is then seen to break down in the limiting case of a crack. However, a closer analysis reveals that sensitivity formulas suitable for BEM implementation can still be established. First, particular sensitivity formulas are obtained for special shape transformations (translation, rotation or expansion of the crack) for either two- or three-dimensional geometries which, except for the case of crack expansion together with dynamical governing equations, are made only of surface integrals (three-dimensional geometries) or line integrals (two-dimensional geometries). Next, arbitrary shape transformations are accommodated by using an additive decomposition of the transformation velocity over a tubular neighbourhood of the crack front, which leads to sensitivity formulas. This leads to sensitivity formulas involving integrals on the crack, the tubular neighbourhood and its boundary. Finally, the limiting case of the latter results when the tubular neighbourhood shrinks around the crack front is shown to yield a sensitivity formula involving the stress intensity factors of both the forward and the adjoint solutions. Classical path-independent integrals are recovered as special cases. The main exposition is done in connection with the scalar transient wave equation. The results are then extended to the linear time-domain elastodynamics framework. Linear static governing equations are contained as obvious special cases. Numerical results for crack shape sensitivity computation are presented for two-dimensional time-domain elastodynamics
Effects of drip irrigation on the yield of strawberry plants grown under arable conditions
ArticleThe study investigated the effects of drip irrigation on the yield of ‘Honeoye’
strawberry plants for commercial purposes grown under arable conditions throughout the harvest
season. The plants were irrigated at irregular intervals depending on natural precipitation. Crop
yields and fruit parameters (diameter, length, individual weight, count per plant) were compared
on several harvest dates. Statistical analysis has shown that irrigation has a significant impact on
yield and fruit parameters. The irrigated plants yielded more strawberries, which also had a larger
diameter, length, and individual weight
Gravitational Equilibrium in the Presence of a Positive Cosmological Constant
We reconsider the virial theorem in the presence of a positive cosmological
constant Lambda. Assuming steady state, we derive an inequality of the form rho
>= A (Lambda / 4 pi GN) for the mean density rho of the astrophysical object.
With a minimum at Asphere = 2, its value can increase by several orders of
magnitude as the shape of the object deviates from a spherically symmetric one.
This, among others, indicates that flattened matter distributions like e.g.
clusters or superclusters, with low density, cannot be in gravitational
equilibrium.Comment: 7 pages, no figure
A note on the Cops & Robber game on graphs embedded in non-orientable surfaces
The Cops and Robber game is played on undirected finite graphs. A number of
cops and one robber are positioned on vertices and take turns in sliding along
edges. The cops win if they can catch the robber. The minimum number of cops
needed to win on a graph is called its cop number. It is known that the cop
number of a graph embedded on a surface of genus is at most ,
if is orientable (Schroeder 2004), and at most , otherwise
(Nowakowski & Schroeder 1997).
We improve the bounds for non-orientable surfaces by reduction to the
orientable case using covering spaces.
As corollaries, using Schroeder's results, we obtain the following: the
maximum cop number of graphs embeddable in the projective plane is 3; the cop
number of graphs embeddable in the Klein Bottle is at most 4, and an upper
bound is for all other .Comment: 5 pages, 1 figur
Evidence of Pentaquark States from K+ N Scattering Data?
Motivated by the recent experimental evidence of the exotic B = S = +1
baryonic state Theta(1540), we examine the older existing data on K+ N elastic
scattering through the time delay method. We find positive peaks in time delay
around 1.545 and 1.6 GeV in the D03 and P01 partial waves of K+ N scattering
respectively, in agreement with experiments. We also find an indication of the
J=3/2 Theta* spin-orbit partner to the Theta, in the P03 partial wave at 1.6
GeV. We discuss the pros and contras of these findings in support of the
interpretation of these peaks as possible exotics.Comment: 10 pages, 4 figure
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