Позиціонування вугільної галузі у зовнішньому енергетичному балансі України

Здійснено формування зовнішнього енергетичного балансу з розрахунком показника чистого експорту. Виконано комплексну оцінку співвідношення обсягів виробництва та споживання вугілля в Україні. Виявлено невідповідність обсягів виробленого та спожитого вугілля та його акумуляцію в Україні. Обґрунтовано необхідність зменшення обсягів імпорту вугілля. Ключові слова: виробництво, зовнішній баланс, імпорт, комплексна оцінка, споживання, формування, чистий експорт.Осуществлено формирование внешнего энергетического баланса с расчетом показателя чистого экспорта. Выполнена комплексная оценка соотношения объемов производства и потребления угля в Украине. Выявлены несоответствие объемов произведенного и потребленного угля и его аккумуляция в Украине. Обоснована необходимость уменьшения объемов импорта угля. Ключевые слова: внешний баланс, импорт, комплексная оценка, потребление, производство, формирование, чистый экспорт.Under present-day conditions it is important to maximize the consumption of energy resources produced in Ukraine, in particular coal resources. It will contribute to solving several macroeconomic problems of Ukraine like raising the energy assurance level as a component of national security of Ukraine, improving the competitiveness of domestic enterprises and the trade balance of Ukraine. At the present stage of development the most popular energy resources are oil and natural gas which is conditioned by their high heating and ecological characteristics. At the same time the reduction of these resources, irregularity of their deposits and other objective factors make for consumption of local energy resources, in particular coal resources. It is defined that foreign energy balance is an index system that shows the demand-consumption ratio of an energy resource in a given period of time inside the country. A foreign energy balance model has been designed which includes calculation of the net export and makes it possible to clear up the modern tendencies that established in our country’s external economic relations of energy resources trade. It has been proved that the basic factor reducing the net export of energy resources is a great volume of imported natural gas though the trade balance of coal and peat operations is negative as well. A complex evaluation of production and consumption ratio of coal in Ukraine based on reduction coefficient to oil equivalent has been carried out which makes it possible to reveal the discrepancy between the volume of coal produced and the volume of coal consumed with its latter accumulation in Ukraine. The necessity of reducing the volume of coal import is proved. Keywords: foreign energy balance, import, complex evaluation, consumption, production, formation, net export

A stochastic model of congestion caused by speed differences

The authors study interaction on a two-lane road between the trips of two types of drivers who differ by their desired speeds. The difference in desired speeds causes congestion, because slow vehicles force fast vehicles to reduce their speed. Results for this type of congestion with respect to tolling are very different from those of the classic Pigou--Knight model, where the marginal external costs are an increasing function of the number of road users. In our model we find the opposite result: the marginal external costs of slow vehicles are a decreasing function of the number of slow vehicles. This leads to rather different policy recommendations

A stochastic model of congestion caused by speed differences

We study interaction between the trips of two types of drivers on a two-lane road who differ by their desired speeds. The difference in desired speeds causes congestion, because slow drivers force fast drivers to reduce their speed. An interesting aspect of this type of congestion is that results with respect to tolling are very different from those of the classical Pigou-Knight model where the marginal external costs are an increasing function of the number of road users. In our model we find the opposite result: the marginal external costs of slow drivers are a decreasing function of the number of slow drivers. This leads to rather different policy recommendations. In many situations either laissez faire (no tolling or traffic restrictions) or prohibition of slow drivers to enter the road is in practice (i.e. taking into account costs associated with tolling) the optimal policy. This conclusion hardly changes if the possibility of overtaking is introduced into the model

Remote sensing of water constituent concentrations using time series of in-situ hyperspectral measurements in the Wadden Sea

This study aimed to investigate the capability of the two-stream radiative transfer model 2SeaColor for the simultaneous retrieval of Chlorophyll-a (Chla), Suspended Particulate Matter (SPM) and Colored Dissolved Organic Matter (CDOM) concentrations from remote sensing measurements under various conditions (i.e., solar zenith angle values (SZAs) and water turbidity levels). For this evaluation, a time series of diurnal in-situ hyperspectral measurements of remote sensing reflectance (Rrs) concurrent with in-situ measured Chla and SPM concentrations between 2008 and 2010 by the NIOZ jetty station (the NJS), located in the Dutch part of the Wadden Sea, was used. Validation of the model retrievals against in-situ measurements showed an acceptable accuracy (Chla: R2= 0.80 and RMSE = 2.98 [mg m−3]; SPM: R2= 0.89 and RMSE = 2.53 [g m−3]) with good agreement between the temporal trends of measured and retrieved concentration values over multiple years. However, the model inversion results yielded less good estimates at SZA > 60° during winter. Furthermore, the effect of the tide on the variation of daily time series of Chla and SPM concentrations was analyzed. At the particular NJS location, the tidal effects on the concentrations of SPM and Chla were found to be small. The capability of the 2SeaColor model to retrieve reliable estimates, and the favorable location of the NJS, which is little influenced by tidal phase variations, contribute to a better understanding of the long-term variability of Chla and SPM concentrations. The results of this study may support the ongoing efforts on Sentinel-3 Ocean and Land Color Instrument (OLCI) calibration and validation at the Dutch Wadden Sea