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Search Results: 1 - 10 of 30986 matches for " ?…??lipek Z. "
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Influence of moisture content and number of mechanical impacts, upon the energy and sprouting capacity of wheat grains
Fr???…czek J.,?…??lipek Z.
International Agrophysics , 1998,
Abstract: The most frequent reason for the damage inflicted on cereal grains results from the shock and mechanical impact of harvesting, cleaning and transport. The characteristic of these processes of that the applied forces is operate in a relatively short time and change in an unpredictable way. The present research aims to define the impact of multiple loads and the moisture content of wheat grains upon the change in its biological value assessed through the energy and force of germination. The simulation of loads was performed in a specially constructed impact unit, using the elastic deformation energy of a spring. The grains where hit, successively 1, 5, 10, 15, 20,25 and 30 times are subjected to a germination test. The research shows a statistically significant influence of moisture content and multiple mechanic impacts upon the biological value of wheat grains subjected to dynamic loads. The implemented regression analysis shows the highest decline of biological value in the interval 1 to 20 impacts. The harvesting and post-harvest processing of wheat grains ought to be effected at a moisture content level below 18%.
Fatigue strength of wheat grains. Part 2. The fatigue strength index for wheat grain
Fr???…czek J.,?…??lipek Z.
International Agrophysics , 1999,
Abstract: In the presented research, fatigue tests were conducted in which a load was applied in the from of a mechanic impact. In the authors opinion, it is the best method to simulate natural conditions, where grains are subjected to multiple stress during the entire technological cycle. Significant emphasis in relation to the quality of sowing material requires the application of precise me-thods for the assessment of changes in biological quality (usually estimated through the strength and energy of germination) in the course of technological processes. However, such analysis requires a number of germination tests. The presented research results are a continuation of the scholarly search aimed at defining an objective, rapid method for assessing the fatigue resistance of wheat grain. The fatigue measurements conformed to the methods proposed in part one. The statistical analysis was made to define the correlation between resistance indicators and corresponding values of germination capacity and energy. The above revealed that the index, calculated following the 5th impact, best describes grain behavior - from the viewpoint of fatigue resistance.
Fatigue strength of wheat grains. Part 1. The analysis of grain deformation at multiple loads
Fr???…czek J.,?…??lipek Z.
International Agrophysics , 1999,
Abstract: In the majority of studies concerning the evaluation of grain resistance, the authors usually make use of the method of visual evaluation of grain condition - with respect both to external and internal damage (X-ray radiographical method). However, it is a subjective method and its application excludes the possibility of comparing the results acquired by different people. Therefore, in the research carried out an analysis was conducted on the process of deformation of single wheat grains of different moisture content, subject to multiple loads of percussive, in order to determine an objective resistance index. Wheat grain husked manually from ears was used in the research. A sample of selected grain was loaded on a spe- cial percussive stand. During impact (deformation) was regis- tered as well as the corresponding input (reaction) value.
Interaction of individual surface microridges in the course of friction between construction walls and plant material
Fr???…czek J.,Kaczorowski J.,?…??lipek Z.
International Agrophysics , 1999,
Abstract: The paper presents the analysis of a typical example of plastic micro-contact in the course of mutual slide of processed vegetative material and construction surface. One of the theories of border load capacity was applied; i.e., the method of integration along-side the feature curves. In effect, the border load capacity of single surface microridges was defined, in the course of mutual friction between the construction and processed vegetative material.
Measurement of grain surface roughness
Fr???…czek J.,Kaczorowski J.,?…??lipek Z.
International Agrophysics , 2000,
Abstract: In the research on the friction of vegetative grain-structure, an essential problem lies in the appropriate determination of the condition of the surface layer of elements in mutual contact. The analysis must define both tensile strength parameters and the surface topography. Most frequently, surface geometry is defined by roughness. Compared to the traditional methods applied for the construction materials, the measurement of roughness in this case is more difficult due to the cellular structure and multifarious shapes of individual skeletons, while low surface hardness (especially at significant humidity) excludes the possibility of applying mechanical methods. For these reasons, an attempt was made to develop a rapid and simple method for the measurement of grain surface roughness relying on the optical procedure. The measurement bench consists of a stereo-microscope with a trinoculare and a camera linked to the computer through an analogue-digital processor. The entire measurement set is equipped with a MultiScan software, where a special picture processing was applied as described below in the paper. A computer analysis of the picture allows to carry out an automatic and precise measurement of the profile roughness in any selected point on the grain surface.
Parton transverse momenta and Drell-Yan dilepton production
Szczurek, Antoni; lipek, Gabriela
High Energy Physics - Phenomenology , 2008, DOI: 10.1103/PhysRevD.78.114007
Abstract: The differential cross section for the dilepton production is calculated including Fermi motion of hadron constituents as well as emission from the ladders in the formalism of unintegrated parton distributions. We use unintegrated parton distributions which fulfil Kwieci\'nski evolution equations. Both zeroth- and first-order (for matrix element) contributions are included. We calculate azimuthal angular correlations between charged leptons and deviations from the $p_t(l^+) = p_t(l^-)$ relation. We concentrate on the distribution in dilepton-pair transverse momentum. We find incident energy and virtuality dependence of the distribution in transverse momentum of the lepton pair. We study also azimuthal correlations between jet and dilepton pair and correlation in the $(p_{1t}(jet),p_{2t}(l^+ l^-))$ space. The results are compared with experimental data of the R209 and UA1 collaborations.
Historical and mathematical aspects of iterative solutions for Monte Carlo simulations
Was, Z.
High Energy Physics - Phenomenology , 2008,
Abstract: Over the last 25 years Monte Carlo programs were being developped in Cracow in the group guided by Prof. Stanislaw Jadach. Many of those programs became standard in their application domains. In the following let us review some aspects of such projects which were probably at the foundation of their success. We will concentrate on mathematical aspects of their design and history of their construction. It is rather difficult to cover 25 years of the research in a single talk. That is why, I have organized my presentation around Monte Carlo PHOTOS but stressing its relation to other activities and projects often realized together with Prof. Jadach. Many of omitted aspects will find their way into other perentations collected in this volume. I will concentrate on issues related to phasespace parametrization and spin amplitudes as used in our Monte Carlo programs such as MUSTRAAL, TAUOLA or KKMC and their similarities and differences with respect to solution used in PHOTOS.
Trefoil knot and ad-hoc classification of elementary fields in the Standard Model
Z. Was
Physics , 1997, DOI: 10.1016/S0370-2693(97)01346-4
Abstract: We present an arbitrary model based on the trefoil knot to construct objects of the same spectrum as that of elementary particles. It includes `waves' and three identical sets of sources. Due to Lorentz invariance, `waves' group into 3 types of 1, 3 and 8 objects and `sources' consists of 3 identical sets of 30+2 elements, which separate into: 1 * 1 * 2 + 1 * 2 * 2 + 3 * 2 * 2 + 3 * 1 * 2 + 3 * 1 * 2 and another 1 * 1 * 2 group (which does not match classification of the Standard Model fields). On the other hand, there is no room in this construction for objects directly corresponding to Higgs-like degrees of freedom.
TAUOLA the library for tau lepton decay, and KKMC/KORALB/KORALZ/... status report
Z. Was
Physics , 2000, DOI: 10.1016/S0920-5632(01)01200-2
Abstract: The status of the Monte Carlo programs for the simulation of the $\tau$ lepton production in high energy accelerator experiments and decay is reviewed. In particular, the status of the following packages is discussed: (i) TAUOLA for tau-lepton decay, (ii) PHOTOS for radiative corrections in decays, (iii) KORALB, KORALZ, KKMC packages for tau-pair production in e+e- collisions and (iv) universal interface of TAUOLA for the decay of tau-leptons produced by``any'' generator. Special emphasis on requirements from new and future experiments is given. Some considerations about the software organization necessary to keep simultaneously distinct physics initializations for TAUOLA are also included.
New hadronic currents in TAUOLA: for confrontation with the experimental data
Z. Was
Physics , 2012, DOI: 10.1016/j.nuclphysbps.2012.02.040
Abstract: The status of implementation of new hadronic currents into the Monte Carlo system for simulation of tau-lepton production and decay in high-energy accelerator experiments is reviewed. Since the tau-lepton conference in 2010 substantial progress was achieved: (i) For the TAUOLA Monte Carlo generator of tau-lepton decays, automated and simultaneous use of many versions of form factors for the calculation of optional weights for fits was developed and checked to work in the Belle and BaBar software environment. Alternative parameterizations of hadronic currents based on the Resonance Chiral approach are available now. This was achieved for more than 88% of the total tau hadronic width. (ii) the TAUOLA universal interface based on HepMC (the C++ event record) is available. This is the case for C++ users of PHOTOS Monte Carlo for radiative corrections in decays, as well. An algorithm for weighted events to explore spin effects in analysis of hard processes was prepared. (iii) Kernels featuring a complete first-order matrix element are available now for PHOTOS users interested in decays of Z and W bosons. New tests with different options of matrix elements for those and for Kl3 decays are available as well. Presented results illustrate the status of the projects performed in collaboration with Zofia Czyczula, Nadia Davidson, Tomasz Przedzinski, Olga Shekhovtsova, Elzbieta Richter-Was, Pablo Roig, Qingjun Xu and others.
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