116 research outputs found
The Effectiveness of Nitrogen Rates on Winter Wheat and White Clover Bi-Cropping Grown for Silage
Whole-crop cereals harvested for silage cover c. 500,000 ha in Europe (Wilkins & Kirilov, 2003). Generally dry matter (DM) yield of small-grain cereals is lower than that of maize. In some investigations, DM yield (of high nutritional value) reached 15 t/ha (Balsdon et al. 1997; Clements et al. 1997). Whole-crop silage produced in a bi-cropping system offers more balanced forage compared to pure cereals and legumes. Nitrogen rates can be decreased with bi-cropping. The aim of this investigation was to compare nitrogen effectiveness using two methods of winter wheat cultivation: direct drilling into stubble and bi-cropping with white clover
The Influence of Winter Wheat and White Clover Bi-Cropping System on White Clover Sward Parameters
Whole-crop silage produced in a bi-cropping system represents a low-input forage production system (Clements et al., 1997). Depressing competition of white clover (by mowing or spraying with herbicides) when winter wheat starts its growth is necessary in this system. Winter wheat also competes with white clover during crop growth. The number of growing points as well as the length and weight of stolon are the main parameters that characterise the persistence of white clover (Jorgensen & Ledgard, 1997; Marriott & Haystead 1990). The purpose of the present investigation was to study the effects of a bi-cropping system on some parameters of white clover
DYNAMIC RESPONSE OF A WHEELSET TO VERTICAL FAULTS AT RAIL WELDS
In this paper, localised vertical geometrical faults at rail welds are considered. The aim is
to predict maximum permissible irregularity sizes at such faults, assuming continuously
welded track. To achieve this, the criteria of maximum accelerations and dynamic peak-
wheel-rail forces between welds can be used. Theoretical results were partly controlled by
experiments and discussed in relation to other studies
Dziecko jako osoba i inspiracja samowychowania rodziców
The discussion concerning family upbringing the most often takes into account only those inquiries which are related to the impacts of parents in relation to a child, and it avoids the wide possibilities of feedback interactions when a child becomes an inspiration for parents to improve themselves. This article presents the available areas of activity which parents can use in their pursue to self-improvement. The motive for such actions is not only parents’ concern of the welfare of a child, but also the desire for self-development. Both motives should be harmonized, and never divergent.W rozważaniach o wychowaniu w rodzinie najczęściej uwzględnia się jedynie te dociekania, które odnoszą się do oddziaływań rodziców względem dziecka, natomiast pomija się szerokie możliwości oddziaływań zwrotnych, gdy osoba dziecka staje się inspiracją dla rodziców do pracy nad sobą. Artykuł ukazuje w tym drugim zakresie pewne potencjalnie istniejące obszary aktywności do zagospodarowania przez rodziców. Motywem podjęcia takich działań jest nie tylko troska rodziców o dobro dziecka, lecz także pragnienie własnego rozwoju. Oba motywy powinny być z sobą zharmonizowane, a nigdy rozbieżne
Quantum Electrodynamics of qubits
Systematic description of a spin one-half system endowed with magnetic moment
or any other two-level system (qubit) interacting with the quantized
electromagnetic field is developed. This description exploits a close analogy
between a two-level system and the Dirac electron that comes to light when the
two-level system is described within the formalism of second quantization in
terms of fermionic creation and annihilation operators. The analogy enables one
to introduce all the powerful tools of relativistic QED (albeit in a greatly
simplified form). The Feynman diagrams and the propagators turn out to be very
useful. In particular, the QED concept of the vacuum polarization finds its
close counterpart in the photon scattering off a two level-system leading via
the linear response theory to the general formulas for the atomic
polarizability and the dynamic single spin susceptibility. To illustrate the
usefulness of these methods, we calculate the polarizability and susceptibility
up to the fourth order of perturbation theory. These {\em ab initio}
calculations resolve some ambiguities concerning the sign prescription and the
optical damping that arise in the phenomenological treatment. We also show that
the methods used to study two-level systems (qubits) can be extended to
many-level systems (qudits). As an example, we describe the interaction with
the quantized electromagnetic field of an atom with four relevant states: one S
state and three degenerate P states.Comment: 23 pages, 6 figure
Software design for the control system for Small-Size Telescopes with single-mirror of the Cherenkov Telescope Array
The Small-Size Telescope with single-mirror (SST-1M) is a 4 m Davies-Cotton
telescope and is among the proposed telescope designs for the Cherenkov
Telescope Array (CTA). It is conceived to provide the high-energy ( few TeV)
coverage. The SST-1M contains proven technology for the telescope structure and
innovative electronics and photosensors for the camera. Its design is meant to
be simple, low-budget and easy-to-build industrially.
Each device subsystem of an SST-1M telescope is made visible to CTA through a
dedicated industrial standard server. The software is being developed in
collaboration with the CTA Medium-Size Telescopes to ensure compatibility and
uniformity of the array control. Early operations of the SST-1M prototype will
be performed with a subset of the CTA central array control system based on the
Alma Common Software (ACS). The triggered event data are time stamped,
formatted and finally transmitted to the CTA data acquisition.
The software system developed to control the devices of an SST-1M telescope
is described, as well as the interface between the telescope abstraction to the
CTA central control and the data acquisition system.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
Prototype of the SST-1M Telescope Structure for the Cherenkov Telescope Array
A single-mirror small-size (SST-1M) Davies-Cotton telescope with a dish
diameter of 4 m has been built by a consortium of Polish and Swiss institutions
as a prototype for one of the proposed small-size telescopes for the southern
observatory of the Cherenkov Telescope Array (CTA). The design represents a
very simple, reliable, and cheap solution. The mechanical structure prototype
with its drive system is now being tested at the Institute of Nuclear Physics
PAS in Krakow. Here we present the design of the prototype and results of the
performance tests of the structure and the drive and control system.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
DigiCam - Fully Digital Compact Read-out and Trigger Electronics for the SST-1M Telescope proposed for the Cherenkov Telescope Array
The SST-1M is one of three prototype small-sized telescope designs proposed
for the Cherenkov Telescope Array, and is built by a consortium of Polish and
Swiss institutions. The SST-1M will operate with DigiCam - an innovative,
compact camera with fully digital read-out and trigger electronics. A high
level of integration will be achieved by massively deploying state-of-the-art
multi-gigabit transmission channels, beginning from the ADC flash converters,
through the internal data and trigger signals transmission over backplanes and
cables, to the camera's server link. Such an approach makes it possible to
design the camera to fit the size and weight requirements of the SST-1M
exactly, and provide low power consumption, high reliability and long lifetime.
The structure of the digital electronics will be presented, along with main
physical building blocks and the internal architecture of FPGA functional
subsystems.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
Using muon rings for the optical throughput calibration of the SST-1M prototype for the Cherenkov Telescope Array
Imaging Atmospheric Cherenkov Telescopes (IACTs) are ground-based instruments
devoted to the study of very high energy gamma-rays coming from space. The
detection technique consists of observing images created by the Cherenkov light
emitted when gamma rays, or more generally cosmic rays, propagate through the
atmosphere. While in the case of protons or gamma-rays the images present a
filled and more or less elongated shape, energetic muons penetrating the
atmosphere are visualised as characteristic circular rings or arcs. A
relatively simple analysis of the ring images allows the reconstruction of all
the relevant parameters of the detected muons, such as the energy, the impact
parameter, and the incoming direction, with the final aim to use them to
calibrate the total optical throughput of the given IACT telescope. We present
the results of preliminary studies on the use of images created by muons as
optical throughput calibrators of the single mirror small size telescope
prototype SST-1M proposed for the Cherenkov Telescope Array.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
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