Dr. Paulina Szafrańska from the PAS Mammal Research Institute in Białowieża explains why weasels range so greatly in size.

The paper includes a summary and a background of long-time research conducted by a research team in the Institute of Electrical Engineering and Computer Science at SilesianUniversity of Technology. The researchwork has principally been related to selected problems in the field of analysis and synthesis of systems aimed at symmetrisation and improvement of some power quality parameters. This paper constitutes a first part of the report on the research. It has been devoted to effective elimination of higher harmonics and reactive power compensation by means of parallel active power filters. The other problem discussed in this paper is related to this issue and it is very important from the economic point of view; it addresses optimal sizing and placement of active power filters in investigated power networks.

The length of crystalline cones (cc) is proportional to krill body length and this proportion can be described by the equation L cc = L krill x 1.679 + 52.032 ( cc — μm; L krill - mm). By measuring cc one can determine the size of krill with the precision of 2—3 mm. The structure of crystalline cones is not crystal, and the elemental composition includes much of S and Ca. Crystalline cones are often found in the stomach and feces of animals feeding on krill.

This paper presents the optimal sizing of PV/Wind/Fuel Cell/Battery Hybrid Energy System for energizing a Small Scale Industrial Application or a village domestic load of 200 kW. HOMER software is used for simulation of the complete system. The solar radiation data and wind speed data used in this paper are for the place of Coimbatore, Tamil Nadu, India which is located 11.0183° N longitude and 76.9725° E latitude. The optimized sizes of components of Hybrid Power System (HPS) are found based on Levelised Cost of Energy (LCE) and total Net Present Cost (NPC). The results are presented and compared for five different combinations of HPS components. Suggestions are also presented to choose the low cost system which produces energy at low LCE.

Current power grid and market development, characterized by large growth of distributed energy sources in recent years, especially in Europa, are according energy storage systems an increasingly larger field of implementation. Existing storage technologies, e.g. pumped-storage power plants, have to be upgraded and extended by new but not yet commercially viable technologies (e.g. batteries or adiabatic compressed air energy storage) that meet expected demands. Optimal sizing of storage systems and technically and economically optimal operating strategies are the major challenges to the integration of such systems in the future smart grid. This paper surveys firstly the literature on the latest niche applications. Then, potential new use case and operating scenarios for energy storage systems in smart grids, which have been field tested, are presented and discussed and subsequently assessed technically and economically.

The efficient, stable and reliable operation of the blast furnace secures the proper quality of coke, which is one of the basic components of the blast furnace charge. In modern blast-furnace technology, when using substitute fuels, i.e. coal dust, the role of coke is extremely important. For this reason, the demands placed on its quality increase. Domestic coking plants have a limited base of Polish high quality coking coals at their disposal, therefore the full use of their coking properties is extremely important. The grain composition of the coal blend is one of the basic factors affecting the quality of the produced coke. This influence depends on the quantity and quality of coal components that make up the blend. In the conducted research, 21 coking coals, differing significantly in the degree of rank and origin (Polish and overseas coals), it was shown that the separated grain classes differ in properties, both coking properties and the degree of devolatalization during heating. In analyzing the obtained results, it was observed that the grain volume growth occurs essentially in the temperature range between the beginning and the maximum of fluidity. It has been shown that there is a linear correlation between the temperature corresponding to maximum fluidity and the temperature at which the maximum rate of evolution of volatiles enters. The presented phenomena accompany the emergence of coal expansion pressure during the coking process and they are its primary causes. The presented results can be an important guide for preparing the milling of coal for the coking process.

The paper aims at the empirical evaluation of the impact of bank size (as measured by median total assets) on the value relevance of two key accounting variables, i.e. book values of equity and net earnings, in terms of their joint explanatory power in the regression model and the relative responsiveness of bank market values to the changes in those variables. The research is based on the multiple linear regression analysis after controlling for the presence of fixed and random effects. The examined sample covers all domestically-based commercial banks listed on the Warsaw Stock Exchange over the period 1998–2017. The final pooled sample comprises 18 banks and 271 bank-year observations. The findings of the study suggest that the equity investors perceive the joint informational content of book values and earnings of larger banks as more value relevant in comparison to the accounting numbers reported by their smaller peers. The responsiveness of banks’ market values to the changes in each of the explanatory variables seems, however, to be affected by their size in a different way. As expected, book values of equity have turned out to be significantly more informative for smaller banks, whereas the evidence regarding the impact of size on the responsiveness of bank market values to the changes in net earnings is ambiguous. Although larger banks appear to exhibit a higher sensitivity of stock prices to variations in net earnings per share than their smaller peers, the difference between the examined subsamples is not statistically significant.

We provide a detailed analysis of a unifying theoretical framework forinnovation and corporate dynamics that encompasses the Gibrat’s Law of Proportionate Effect and the Simon growth process as particular instances. The predictions of the model are derived in terms of (i) firm size distribution, (ii) the distribution of firm growth rates, and (iii-iv) the relationships between firm size and the mean and variance of firm growth rates. We test the model against data from the worldwide pharmaceutical industry and find its predictions tobe in good agreement with empirical evidence on all four dimensions. Our unifying stochastic framework can also be used to describe corporate dynamics in different industries and as a benchmark for discriminating among alternative data generating processes.

Experiences of subregional cities in programming of urban renewal. The aim of the article is to analyze and evaluate the experience of selected subregional cities in revitalization programming. At the beginning, the strategic policy of the state towards subregional centers was defined. The guidelines from the National Spatial Development Concept, the National Urban Policy and the Strategy for Responsible Development were pointed out. Then, examine in detail the activities carried out so far in 4 cities, which as a result of the administrative reform in 1999 lost the status of the provincial city, i.e. in Ciechanów, Legnica, Piła and Przemyśl. Current documents have been characterized, in particular, the specificity of areas covered by revitalization has been described. Next, the leading directions of transformations of these areas were presented, resulting from the adopted revitalization policy. This allowed for the formulation of certain generalizations about the specificity of the process of renewal of degraded areas in subregional centers in Poland.

The problem of of the use of fly ash still constitutes a research and exploration area for scientists. This is due to the fact that, 6,000,000 Mg of coal combustion by-products (CCB) are storage on landfills yearly in Poland alone. One of the potential directions of using fly ash is to use it as a substrate in hydrothermal syntheses of mesoporous materials (synthetic zeolites). Zeolites are aluminosilicates with a spatial structure. Due to their specific structure they are characterized by a number of specific properties among others molecular-sieve, ion-exchange and catalytic that can be used in engineering and environmental protection. So far, the synthesis has been carried out using coal combustion by-products such as fly ash or microsphere. The article analyzes whether separation from the fly ash of the appropriate fraction (below 63 μm) will affect the formation of zeolite grains. The syntheses were carried out using class F fly ash and the fraction separated from it, which was obtained by sieving the ash through a 63 μm sieve. Chemical (XRF) and mineralogical (XRD, SEM-EDS) analyzes were carried out for substrates as well as the obtained reaction products. In the case of substrates, the analysis did not show any significant differences between the ash and the separated fraction. However, in products after synthesis (Na-X zeolite with a small amount of Na-P1 zeolite, and small amounts of quartz and unreacted aluminosilicate glass - mullite) higher aluminum and sodium contents were observed from the separated fraction, with a lower calcium and potassium content. A small proportion of illite was observed on the diffraction curve of the zeolite from the fraction. Observations of grain morphology showed no differences in formation. Based on the conducted analyzes, it can be stated that, considering the economics of the synthesis process, the separation of fine fractions from the fly ash does not affect the quality of the synthesis process.

There are more and more new development challenges emerging in Polish cities and regions recently. Because of those challenges we can observe an increase of the role of cities and associated environments. The concept of cities’ impact on the environment is a result of many processes, such as: suburbanization, reurbanization, increasing population mobility, development of transport systems, innovation, or entrepreneurship. A city is a complex entity, it is a subject to dynamic changes, to understand which we need interdisciplinary knowledge or the combination of many different approaches along with an attempt to draw many conclusions. We can find numerous theoretical examples describing city-regional environment relations in the literature. In general, these models explain the relationship between economically strong cities (metropolis) and the regions. However, there is not much literature and research explaining the nature and strength of relationships with medium-sized cities. There are also very few ideas for developing the potential of medium-sized cities in polish national policy. The aim of the article is to present disproportions in the development of medium-sized cities in voivodships of Eastern Poland in 2010-2017. The author will also present the possibility of using a synthetic measure to assess and recognize the spatial diversity of medium-sized cities development.

This article considers designing of a renewable electrical power generation system for self-contained homes away from conventional grids. A model based on a technique for the analysis and evaluation of two solar and wind energy sources, electrochemical storage and charging of a housing area is introduced into a simulation and calculation program that aims to decide, based on the optimized results, on electrical energy production system coupled or separated from the two sources mentioned above that must be able to ensure a continuous energy balance at any time of the day. Such system is the most cost-effective among the systems found. The wind system adopted in the study is of the low starting speed that meets the criteria of low winds in the selected region under study unlike the adequate solar resource, which will lead to an examination of its feasibility and profitability to compensate for the inactivity of photovoltaic panels in periods of no sunlight. That is a system with fewer photovoltaic panels and storage batteries whereby these should return a full day of autonomy. Two configurations are selected and discussed. The first is composed of photovoltaic panels and storage batteries and the other includes the addition of a wind system in combination with the photovoltaic system with storage but at a higher investment cost than the first. Consequently, this result proves that is preferable to opt for a purely photovoltaic system supported by the storage in this type of site and invalidates the interest of adding micro wind turbines adapted to sites with low wind resources.

In agriculture, the mixing of pesticides in tanks is a common practice. However, it is necessary to previse possible physical-chemical implications of this practice, which may affect the efficiency of the treatments performed. Therefore, the objective of this study was to evaluate the effects of the addition of acaricide to insecticidal spray mixtures on the formation of spray droplets and the interaction with citrus leaves. The experimental design was totally randomized, in a (2 × 3 + 1) factorial scheme for seven treatments. Factor A corresponded to the spray mixture used (isolate or in the mixture). Factor B corresponded to the insecticides tested (lambda-cyhalothrin + thiamethoxam, phosmet, and imidacloprid) and the control consisted of a spray mixture with spirodiclofen only. Nine replications were performed for characterization of the spray droplet size spectrum and four replications for the analysis of the surface tension and the contact angle. The mixture of pesticides showed positive results in terms of application safety. The addition of acaricide to insecticide spray mixtures reduced the surface tension and contact angle of droplets on the adaxial surface of orange leaves. There was an increment in volume median diameter (VMD), a significant reduction in the volume of droplets with drift-sensitive size and improvement in the uniformity of droplet size. Therefore, the addition of acaricide to an insecticide spray mixture positively influenced spray droplet formation and the interaction with citrus leaves providing better coverage and droplet size fractions with an appropriate size for safe and efficient application.

It is challenging to obtain proper leaf wetting. An angled spray could overcome this impediment, but which spray angle is best suited to droplet size is still unknown. In an outdoor pot experiment, seven doses of cycloxydim and sethoxydim were sprayed with single-orifice standard, anti-drift, and air induction (having a fine, medium, and extremely coarse spray quality, respectively) flat fan nozzles, using spray angles of 10°, 20° backward, 0° (vertical), 10°, 20°, 30°, 40°, 50°, and 60° forward relative to the direction of nozzle trajectory on wild barley at the three-leaf stage. Generally, the forward angled spray was better than the backward angled spray. With a standard flat fan nozzle, the forward angling of spray from 0° to 20° reduced the ED50 from 60.24 to 39.85 g a.i. ⋅ ha−1 for cycloxydim and from 150.51 to 81.13 g a.i. ⋅ ha−1 for sethoxydim. With an anti-drift flat fan nozzle, the forward angling of spray from 0° to 30° reduced the ED50 from 72.57 to 50.20 g a.i. ⋅ ha−1 for cycloxydim and from 181.94 to 104.51 g a.i. ⋅ ha−1 for sethoxydim. With an air induction flat fan nozzle, the forward angling of spray from 0° to 40° reduced the ED50 from 102.96 to 45.52 g a.i. ⋅ ha−1 for cycloxydim and from 209.91 to 92.80 g a.i. ⋅ ha−1 for sethoxydim. More angling did not improve the efficacy of these herbicides. Our results revealed that larger spray droplets needed more spray angle than smaller spray droplets to achieve an equal control.