This study presents a flow pump technique usually used for evaluating the permeability of soils, which was, for first time, applied to measure the water permeability of concrete. Additionally, a new easy-to-apply method to determine permeability is proposed, based on a modification of Valenta’s formula. In the calculations, the apparent air content of concrete mixes was taken into account. An additional purpose of the conducted research was to determine the influence of a new generation of polycarboxylate superplasticizer and chemically active admixtures on the permeability, compressive strength, and other properties of concrete. The following four types of concrete were tested: concrete without admixtures, concrete with an admixture to increase the compressive strength, concrete with a superplasticizer, and concrete containing two admixtures simultaneously. The results showed that the proposed method allows to obtain reliable measurements within a very short period of time. The obtained results confirmed that new method may be very useful in engineering practice, particularly in terms of the watertightness of hydrotechnical concretes and the properties of the concretes used in bridge construction, underground parts of office buildings, or sealed tanks.

Surfaces exposed to the night sky cool to temperatures below that of the air.This cooling is due to the nature of the atmospheric thermal radiation. Materials with dissimilar spectral characteristics behave differently.The purpose of the Radiative Cooling Test Facility is to provide a means for quantitative measurement of the cooling rates of exposed surfaces and assemblies. Emphasis is placed upon assemblies which are specifically designed to produce radiative cooling and which therefore offer promise for the reduction of temperatures and/or humidities in occupied spaces.This report documents the hardware and software used to operate the facility, and presents the results of the first comprehensive experiments.A microcomputer-based control/data acqu~s~t~on system was employed to study the performance of two prototype radiator surfaces: 4 mil aluminized polyvinyl fluoride (PVF) and white painted surfaces set f Current Address:American University, Beirut, Lebanon. Princeton University, Princeton, NJ 08540.below polyethylene windscreens.The tested were determined and can be equation Computer simulations of radiative cooling assemblies were used to confirm that, with proper measurement techniques, the measured values of the constants a and b are nearly independent of the magnitudes of wind speed, air temperature, and sky radiance. Thus the cooling performance equation given in this abstract is applicable to a wide range of conditions, requiring only the sky radiance and the absolute air and surface temperatures as input values.-2-CONTENTS

No abstract

The objective of this article is to determine changes in municipal waste management in rural areas after introduction of a new waste management system in 2012. The study includes rural districts of Bielski and Hajnowski administrative districts. The results show that the changes made have contributed to the improvement of waste management in rural areas. The amount of municipal waste collected increased by about 42 kg/inhabitant/year. A considerable part of the population (above 93%) started to separate waste. The new waste management system resulted in considerable costs increase. In a two-person households, which constitute the most in this analysis, the charges for municipal waste disposal increased from 51 to 533%, depending on the rural district and the method of waste collection (mixed waste, separated waste).

Streszczenie: Celem pracy jest określenie ekonomicznej efektywności poprawy termoizolacyjności ścian zewnętrznych murowanego domu jednorodzinnego. W artykule przedstawiono koszt wykonania systemu ETICS w dwóch najczęściej stosowanych technologiach: z płytami polistyrenu EPS oraz z płytami wełny mineralnej. Określono koszty zmienne ogrzewania budynku w kilku wariantach związanych z zastosowaniem różnych systemów grzewczych. Uzyskane wyniki wykazują ekonomiczną efektywność poprawy termoizolacyjności ścian zewnętrznych. Najwyższe wskaźniki uzyskano w przypadku domu ogrzewanego energią elektryczną. Poprawa termoizolacyjności ścian zewnętrznych przy zastosowaniu polistyrenu charakteryzuje się wyższą ekonomiczną efektywnością niż w przypadku wełny mineralnej. Efektywność rozpatrywanej inwestycji spada wraz ze wzrostem izolacyjności cieplnej ścian osłonowych budynku.Słowa kluczowe: izolacyjność cieplna ścian zewnętrznych, system ETICS, zapotrzebowanie budynku na energię, ekonomiczna efektywność termoizolacji, koszt termoizolacji. Summary:The objective of this study is to determine the economic efficiency of increasing the thermal insulation in the external walls of a brick detached house. The paper presents the cost of performing the ETICS system in two most commonly used technologies: with polystyrene and mineral wool boards. The variable costs of heating the model house have been determined in a few variants associated with various heating systems. The obtained results showed that the economic efficiency of improving the thermal insulation of external walls is achieved. The highest indexes were obtained in the case of a model house heated by electricity. The improvement of external walls thermal insulation using polystyrene EPS Ekonomiczna efektywność termoizolacji ścian zewnętrznych murowanego domu mieszkalnego 385shows more economic efficiency than using mineral wool (MW). The effectiveness of the investment considered decreases when the thermal insulation of the external walls inecreases.