Initial public pensions are indexed to the economy-wide average wages, butpensions in progress are indexed to prices, average wages or their combinations– varying across countries and periods. We create a simple overlapping cohortsframework to study the properties of indexing pensions in progress – emphasizinga neglected issue: close wage paths should imply close benefit paths even at realwage shocks. This robustness criterion of an equitable pension system is onlysatisfied by wage indexing, which in turn requires the adjustment of the accrualrate. To minimize the redistribution from low-earning short-lived citizens tohigh-earning long-lived ones, progression should be introduced.

The results of a research into the scale and consequences of the degradation of aquatic ecosystems in Ukrainian Polesie have been detected in article, and the areas of increased anthropogenic pressure have been identified which greatly affect the condition and number of aquatic macrophytes. The biodiversity of sites with different anthropogenic load was evaluated using the biodiversity criteria. In the research, the structural and functional features of macrophytic species diversity within Teteriv River ecological corridor as a typical river landscape of Ukrainian Polesie were determined and described, the floristic composition was determined. Within the ecological zones, the number of species and their projective coverage in areas with different anthropogenic pressures within Teteriv River ecological corridor were determined. The basic criteria for the implementation of deferred biomonitoring based on the analysis of the dynamics of the spe-cies composition of the phytocoenoses of Teteriv River ecological corridor on the indicators of ecological stability and plasticity using the species-specific criteria, are: Margalef species richness index, Sørensen–Dice index, Shannon diversity index, Simpson’s index, and Pielou’s evenness index. Based on the results, correlation dependencies have been constructed, which will allow to obtain data on the stability of the development of aquatic ecosystems according to the data of species surveys. Interconnections between biodiversity indicators and indicators of surface water quality within the Ukrainian Polesie were found; they are the fundamental component of a long-term monitoring of the stability in the development of aquatic phytocenoses.

Drought is known as a normal part of climate and including in a slow-onset natural hazard which may have several im-pacts on hydrology, agriculture, and socioeconomic. Drought monitoring, including its severity, spatial and duration is re-quired and becomes an essential input for establishing drought risk management and mitigation plan. Many drought indices have been introduced and applied in regions with different climate characteristics in the last decades. This paper aims to compare standardized precipitation index (SPI) and rainfall anomaly index (RAI) along with standardized streamflow index (SSI) in Pekalen River Basin, East Java, Indonesia. The statistical association analyses, included the Pearson correlation (r), Kendal tau (τ), and Spearman rho (rs) were performed to examine the degree of consistency between monthly and annual drought index of SPI and RAI. Additionally, the comparative analysis was performed by overlapping both monthly and an-nual drought index from the SPI and RAI with the SSI at hydrological years. The study revealed that the characteristic of the annual drought index between the SPI and RAI exhibits pattern similarity which indicated by the high correlation coeffi-cient between them. Further, the comparative analysis on each hydrological year showed that the SPI and RAI were very well correlated and exhibited a similar pattern with the SSI. Overall, the SPI shows better performance than the RAI for es-timating drought characteristic either monthly or annual basis. Hence, the SPI is considered as a reliable and effective tool for analyzing drought characteristic in the study area.

The use of phytoplankton as an indicator of water pollution is a promising tool for assessment of water quality. The purpose of this study was to determine whether diversity indices, including the species richness and diversity of phyto-plankton, could be used for reliable assessment of water quality in the Wadaslintang Reservoir in Indonesia. Surveys were conducted monthly at eight sites, from July 2019 to October 2019. Phytoplankton was collected during the day at 10:00 until approximately 15:00 in the euphotic zone. The parameters investigated were species richness and the abundance of phytoplankton, as well as water quality parameters listed in Government Regulation Number 82 of 2001. The level of pol-lution was represented biologically by the Shannon–Wiener diversity index and physicochemically by the STORET (stor-age and retrieval of water quality data) index. Moreover, the two indices were compared to determine whether a particular diversity index was more effective for assessment of this reservoir. The results showed that during the dry season, 22 taxa of phytoplankton were present, belonging to Cyanophyta, Chlorophyta, Chrysophyta, and Euglenophyta. During the wet season, 29 taxa were found, belonging to Cyanophyta, Chlorophyta, and Chrysophyta. Based on the Shannon-Wiener index and STORET index, water quality was better during the wet season than during the dry season. The results of water quality assessment using both indices were consistent, but the diversity index was a more sensitive indicator of pollution levels. Therefore, the Shannon–Wiener index is a useful tool for assessment of water quality in the Wadaslintang Reservoir.

We are observing an increase in development activity of the cities with poviat rights nowadays. It is visible especially in the area of obtaining European funds, financial policy, infrastructure or entrepreneurship. Those matters, especially experience of cities with poviat rights as the main beneficiaries became an interesting research area now. The aim of the article is to assess the competitiveness and development level of the cities with poviat rights in voivodships of Eastern Poland. For the purposes of this article, a synthetic measure has been used. Taking into account the availability and comparability of data as well as statistical criteria, the variables describing: financial situation, economy and infrastructure in the system of cities with poviat rights in voivodships of Eastern Poland were adopted. Data from the Local Data Bank of the Central Statistical Office for 2008, 2012 and 2016 were the main source of the article.

Geographical Information Systems have become essential tools for land analysis and the subsequent decision making in many fields of human activity. In the field of mining, GIS applications have appeared in ore deposit modelling, environmental pollution, or planning of mining spaces. In this research, the powerful multicriteria tools of GIS platforms have been applied for the determination of an index that has been called “Exploitability Index”. This index allows analyzing a series of outcrops of industrial aggregates, to help in the selection of the most adequate one to be enhanced from a mining approach. The multicriteria analysis has been applied for its determination, and as a result of this research, a model is proposed. The main criteria that condition the decision have been established in this model, along with their subsequent hierarchization and their weighting. The proposed model is applied to a specific case: the analysis of a series of outcrops of industrial aggregates (ophites) in Cantabria, Spain. After defining the Exploitability Index for those ophitic outcrops, it has been observed that the only deposit that has been classified as very suitable for its exploitation is the only one that has been really exploited, supporting the proposed methodology.

The presented article examines aspects of a PV module testing using natural sunlight in outdoor conditions. The article discusses the physical sense of indexes: atmosphere purity, diffused component content, beam clear sky index. Procedures for their determination are given in relation to both instantaneous and daily values. Their close connection with the values of solar irradiance spectral distribution such as Average Photon Energy and Useful Fraction is demonstrated, as well as their usefulness in module testing in outdoor conditions. Their influence on the conversion of modules made from various absorbers and various technologies is demonstrated

The major impacts on aquatic ecosystems worldwide caused by land use lead to changes in their natural conditions and limitation of water use for various needs. This paper presents the results of the study of the physical and chemical parame-ters and macroinvertebrate assemblage in the White Drin River (or: the Drim River, Alb. the Drini i Bardhë River) basin, the largest in Kosovo. Macroinvertebrate sampled at 11 sites in the river resulted in 5946 collected benthic organisms, which in taxonomic terms belong to 12 orders and 51 families. Of the total number of organisms, 72.28% were Insects, 25.39% Amphipoda crustaceans and 2.33% were Annelide worms and Mollusk. The used biotic indices Biological Moni-toring Working Party (BMWP), Ephemeroptera, Plecoptera, and Trichoptera (EPT), average score per taxon (ASPT) and Stroud Water Research Center (SWRC) classify water quality in excellent category in the sampling site S1 near the source of the White Drin River, whereas in other sampling sites, as a result of pollution, water quality varies on category II–IV. The Pearson's correlation analyses shown that the physical and chemical parameters affect the water quality and the com-position of macroinvertebrates. Our results show that the parameters that adversely affect the BMWP, EPT and ASPT bio-tic indices as well as the Shannon–Wiener, Mergalef and Menhinik diversity indices are: pH, electrical conductivity (EC), total suspended solids (TSS), nitrates (NO3–) and chlorides (Cl–). We can conclude that the anthropogenic impact on White Drin basin affects the physical, chemical and biological parameters of the water therefore these parameters should be con-stantly included in Biomonitoring and Management plans for water resources in Kosovo.

The corporate cost of capital is used by valuators to discount future flows of income from an entity in order to derive a present-day, forward-looking value of that entity. The cost of capital is therefore determined as the weighted cost of the various sources of funding, being typically equity, debt and preference instruments. The tricky and important part is estimating the cost of equity, which usually needs the application of finance models. The study on the texts on mineral valuation or mineral project evaluation demonstrates that the capital asset pricing model (CAPM) is a general model for estimating the cost of equity. However, according to shortfalls and problems relating to it a relatively similar and simpler model i.e. the single-index market model is proposed. The single index market model is an important tool in contemporary research in finance. Much of the importance of the model follows from its 'beta' parameter which, ideally, measures the sensitivity of returns on a security to changes in a market model. To estimate the cost of equity of the mining and cement companies listed in Tehran Stock Exchange (TSE) The single-index market model is selected because of the shortfalls and problems of the CAPM as well as the lack of commercial services for determining the market premium. The regression analysis as well as the statistical analysis is carried out using Excel spreadsheet. The statistic significance of the model is tested using t and F test statistics. The results showed that the independent variable (the rate of return on the market index) has a genuine effect on the dependent variable (the rate of return for the stock) and there is a statistically significant linear relationship between the two variables at significance level of 5%. Finally, the cost of equity formining and cement companies is estimated 25.0% and 31.0% respectively. Knowing the cost of equity, calculating the discount rate will not be very difficult.