Artykuły z różnych czasopism

Type: Collection of articles

Collection items (262)

Difficulties with existing fish passes and their renovation. The pool fish pass on Dłubnia river in Krakow

Radecki-Pawlik, Artur, Voicu, Răzvan, Plesiński, Karol Krystian, Gajda, Grzegorz, Radecki-Pawlik, Bartosz, Voicu, Liliana, Książek, Leszek
2019 - 2019
The aim of study The aim of study was to determine, how the pool fish pass located on the Dłubnia River operates and to formulate recommendations, due to which it will work effectively and will not be an obstacle for migrating fish. Materials and methods Field work. Identification of elements of fish pass that may restrict fish migration on the grounds of standard geometrical dimensions. An attempt to design its repair. Results and conclusions The fish pass does not operate effectively. The paper presents recommendations for its improvement.

Anomalous quartic term in the expansion of the symmetry energy

Zabari, Noemi, Kubis, Sebastian, Wójcik, Włodzimierz
The quartic term in the framework of relativistic mean-field theory with inclusion of scalar meson interactions is investigated. It is shown that the quartic term in the asymmetric expansion of nuclear matter energy may reach very large values. This makes the even power expansion of asymmetry questionable and suggests possible nonanalytic contributions to the energy of matter.

Historic Gardens’ Mosaic in Carpathian Basin. A Transylvanian case study

Fekete, Albert, Hodor, Katarzyna
This is an overview of a study of 100 castle gardens in Transylvania. The research has been undertaken by a substantial number of students, teachers and professionals in the Faculty of Landscape Architecture and Urbanism Budapest, Szent István University. The object was to explore and document the surviving parts of the gardens and estates of the chosen locations while evidence still exists, to complete a missing chapter in European garden history. All the available historic material was assembled, site surveys completed and a full record compiled. The result is a comprehensive overview of 400 years of garden history in the region, relating them to wider historical trends in the area and human use of the wider landscape. Also it acts as an inventory of the current state of the gardens, enabling renewal and maintenance plans to be put in place. The research won the Europa Nostra Prize in 2014.

Development strategy in the field of transport of perishable food products based on the SWOT analysis

Gajewska, Teresa
A rise in international trade has increased the need for the transportation of perishable products from producers to end-users in distant locations. Such transportation requires extensive logistics planning to ensure the integrity of the goods transported. The article aims to identify and highlight key strengths and weaknesses of the company, and to identify opportunities and threats that can contribute to improving the competitiveness and thus the quality of services provided. The scope of the data included domestic and international transport of two product groups: food and agricultural products. Data were obtained from Eurostat and the Polish Central Statistical Office (GUS) for the years 2010–2015. In order to determine the strategy and enterprise that specializes in the transport of food products, a SWOT analysis was used. The SWOT analysis points clearly to the direction of the business’s development towards strong expansion in the market which is demonstrated by the high figures for the strengths and opportunities (9.48). Compared with 2014, 2015 saw a 14.2% increase in the proportion of foods with a parallel drop in the transport of domestic agricultural produce by nearly 5%. The volume of road transport expressed in tonne/kilometre was 14.5% of the total of EU transport which places Poland second amongst the 28 EU states, after Germany and before Spain and France. The paper demonstrates that the most advantageous development strategy for a domestic transport provider is an aggressive (maxi–maxi) strategy to fully benefit from the opportunities with the use of its strengths.

New lupeol esters as active substances in the treatment of skin damage

Malinowska, Magdalena, Mirosław, Barbara, Sikora, Elżbieta, Ogonowski, Jan, Wojtkiewicz, Agnieszka, Szaleniec, Maciej , Pasikowska-Piwko, Monika, Eris, Irena
The purpose of the research was to obtain new derivatives of natural triterpene lupeol and to evaluate their potential as active substances in the treatment of skin damage. Four new lupeol esters (propionate, succinate, isonicotinate and acetylsalicylate) and lupeol acetate were obtained using an eco-friendly synthesis method. In the esterification process, the commonly used hazardous reagents in this type of synthesis were replaced by safe ones. This unconventional, eco-friendly, method is particularly important because the compounds obtained are potentially active substances in skin care formulations. Even trace amounts of hazardous reagents can have a toxic effect on damaged or irritated tissues. The molecular structure of the esters were confirmed by 1H NMR, 13C NMR and IR spectroscopy methods. Their crystal structures were determined using XRD method. To complete the analysis of their characteristics, physicochemical properties (melting point, lipophilicity, water solubility) and biological activity of the lupeol derivatives were studied. Results of an irritant potential test, carried out on Reconstructed Human Epidermis (RHE), confirmed that the synthesized lupeol derivatives are not cytotoxic and they stimulate a process of human cell proliferation. The safety of use for tested compounds was determined in a cell viability test (cytotoxicity detection kit based on the measurement of lactate dehydrogenase activity) for keratinocytes and fibroblasts. The results obtained showed that the modification of lupeol structure improve its bioavailability and activity. All of the esters penetrate the stratum corneum and the upper layers of the dermis better than the maternal lupeol. Lupeol isonicotinate, acetate and propionate were the most effective compounds in a stimulation of the human skin cell proliferation process. This combination resulted in an increase in the concentration of cells of more than 30% in comparison to control samples. The results indicate that the chemical modification of lupeol allows to obtain promising active substances for treatment of skin damage, including thermal, chemical and radiation burns.

Energy conversion in small water plants with variable speed PM generator

Sobczyk, Tadeusz, Mazgaj, Witold, Szular, Zbigniew, Węgiel, Tomasz
The Small Hydro Power Plants allow to increase the energy amount from re-newable sources, especially from small rivers in mountainous areas. This paper presents a new concept of a energy conversion system for application in a Small Hydropower Plant (SHP) which is based on a permanent magnet generator (PM generator) with a pro-peller turbine integrated with the generator rotor. The PM generator can work at a vari-able speed and therefore energy produced by the PM generator has to be converted by means of a power electronic unit to fit to the three-phase power grid parameters. For this concept, dimensions and parameters of the PM generator were specially designed on ac-count of integration with water turbine. The paper precisely describes elements of energy conversion system and also presents the results of numerical tests for chosen working conditions. An original algorithm of control strategy for power electronic unit was used to adjust generated energy to the required parameters of the three-phase grid.

Small Hydropower Plant with variable speed PM generator

Mazgaj, Witold, Szular, Zbigniew , Węgiel, Tomasz , Sobczyk, Tadeusz
This paper presents a new concept of a Small Hydropower Plant (SHP) which is based on a permanent magnet generator (PM generator) with a propeller turbine integrated with the generator rotor. The PM generator can work at a variable speed and therefore energy produced by the PM generator has to be converted by means of a power electronic unit to fit to the three-phase power grid parameters. The paper describes elements of the energy conversion system and it also presents the results of numerical calculations of this system working.

Aspekty „pracy” w programach preorientacji i orientacji zawodowej oraz doradztwa edukacyjno-zawodowego w systemie oświaty

Piekarski, Marian
2018 - 2019
Artykuł ma na celu pokazanie aspektów „pracy” obecnych w nowych programach preorientacji, orientacji i doradztwa zawodowego wprowadzanych do systemu edukacji. Proaktywna postawa dzieci i młodzieży wobec pracy jest odpowiedzią na dynamiczne zmiany cywilizacyjne i społeczne, które na nadchodzące lata formułują nową definicję pracy.

Analysis of fatigue behavior of composite structures with circular internal delamination

Składanowska, Katarzyna, Sanetra, Izabela, Muc, Aleksander
The aim of the paper is to demonstrate and describe the fatigue failure mechanisms of eight-layer glass-epoxy composites with a central circular delamination, numerical description of the delamination problems and a possible optimal design. There are a few variables (tension and compression forces, number of cycles, construction of the tested plates) which can be changed during the experiment that will very likely provide different results. The problem is to find the link among all those variables to fully describe their influence on the physical behavior of the epoxy plate which is the subject of the experiment. The results are illustrated with the use of the numerical analysis method. Thanks to that, it is possible to describe how the number of cycles, tension force and stress variations affect the whole fatigue process.

Analysis of the rotational capability of the utilization of range of spherical joint used in a passenger automobile McPherson suspension

Kuranowski, Aleksander, Para, Sławomir
In this paper a method is presented how to determine the utilization of range of rotational ability of a ball joint used in a passenger automobile McPherson suspension. A portable measurement arm was used to measure some vehicle’s suspension geometry points as well as the geometry of suspension components. Based on the initial measured data a simulation model was used to estimate the real geometric parameters of the suspension and of the attachment points at the chassis. The damper module’s top mount movement as well as the stiffness characteristics of the control arm bushing allow to simulate the utilization of range of motion capability of the spherical joint as result of the suspension movement under external loads. These loads can result from pass over a bump or cornering movements. The rotational ability of the ball joint and its applied loads can be input for further stiffness analyses by making use of FEM software.