Computing Residential Heat Demand in Urban Space using QGIS. A Case Study for Shumen, Bulgaria

Smart Cities need Smart Energy Planning. This requires knowledge about the spatial configuration of building heat demand, to facilitate circumspect decisions about where and how to renovate the building stock and what type of heating supply technology to implement. This paper presents a tool for static heat demand computation for residential buildings within the open-source Geographical Information System QGIS. It comes in the form of a Python script that analyses building geometries, accounting for walls shared with neighbouring buildings and computing heat demand according to the German norm DIN-4108-6. The novelty of the approach presented here, compared to standard procedures to compute urban heat demand which rely on building typologies, lies in the individualized computation for each building which allows for the inclusion of building specific characteristics not accounted for in standard building typologies

Inequality and Public Policy: A Country Study for Bulgaria

This paper is an attempt for measuring the impact of public policy on the inequality in Bulgaria. An analysis based on the Bulgarian Household Budget Surveys shows that the tax burden in Bulgaria, nevertheless increasing in the upper quintiles, declined between the beginning of the transition period and the year before the EU accession. Using different inequality measures we have found that despite the limited possibilities of the data, taxation policies also contribute to some extend to inequality reduction in Bulgaria. As regards the social transfers, unemployment benefits and child allowances are found to be the main social payments reducing the inequality among Bulgarian households. Using quantile regression is found that the coefficients of the effective tax rates increase across the quintiles for the entire period. The coefficients associated with the share of VAT expenditures in the total income decrease as one moves from the lowest to the highest quintile of the consumption distribution.

Constitutional control as a factor of market economy maintenance

After the change of the social-political system in Bulgaria during the last decades of the XX century, Bulgaria has been facing a great number of difficulties in the transition from planned to market economy. The adoption of a new democratic Constitution has to do with the introduction of new functions of state authorities and the standing for new principles. The subject of this report is the activity of the Constitutional Court (CC) and its role in the enforcement of the basic principle of the market economy in accordance with the Bulgarian basic law the free business initiative. Key words: Constitutional Court, constitutional control, free business initiative, competitiveness, monopoly, consumer protection.Після зміни соціально-політичної системи в Болгарії протягом останніх десятиліть ХХ століття, Болгарія стикається із численними труднощами при переході від економіки планової до ринкової. Ухвалення нової демократичної Конституції має відношення до введення нових функцій державних властей і підтримки нових принципів. У статті розглянута діяльність Конституційного Суду та його роль в здійсненні основного принципу ринкової економіки відповідно до Болгарського основного закону - вільна ділова ініціатива. Ключові слова: Конституційний Суд, конституційний контроль, ділова ініціатива, конкурентоспроможність, монополія, захист споживача.После изменения социально-политической системы в Болгарии в течение последних десятилетий ХХ столетия, Болгария сталкивается с многочисленными трудностями при переходе от плановой к рыночной экономике. Принятие новой демократической Конституции имеет отношение к введению новых функций государственных властей и поддержки новых принципов. В статье рассмотрена деятельность Конституционного Суда и его роли в осуществлении основного принципа рыночной экономики в соответствии с Болгарским основным законом — свободная деловая инициатива. Ключевые слова: Конституционный Суд, конституционный контроль, свободная деловая инициатива, конкурентоспособность, монополия, защита потребителя

Soft-switching Inverter-fed Single-phase Collector Motor Drive

AbstractThis paper deals with the performance analysis of a hand power tool (HPT). The HPT is being driven by a single-phase collector motor drive fed by a PWM voltage source soft-switching inverter. A mathematical model of an electro-mechanic system of a HPT has been worked out. The dynamic model of an electric motor consists of a system of non-linear differential equations that include the resistance and dynamic inductance of an armature and field winding and spinning E.M.F. The proposed drive system is modeled and its performance is simulated in Matlab/Simulink. The simulation results show that a smaller switching loss and higher conversion efficiency are obtained by the proposed soft-switching inverter. The performance of the drive is improved by using voltage regulator when compared with direct connection to the voltage source

Spatial aggregation and visualisation of urban heat demand using graph theory.: An example from Hamburg, Germany.

Because of the physical properties of heat energy, information about the spatial pattern of building heat demand is important for designing climate protection measures in the heating sector (efficiency improvements and renewable energy integration). Many cities in Germany currently prepare ‘heat demand cadastres’ – thematic maps, depicting building heat demand. The growing trend towards open data points into the direction of making these cadastres public, so that different actors can make use of them. However, making such data public may violate the legal requirement of protecting private data. We present a way of tackling this problem with an approach for the aggregation of spatially represented heat demand. Using an algorithm based on graph theory, we group buildings such that the tracing of energetic characteristics and behaviour to individuals is rendered unfeasible. Our method also allows additional constraints to be introduced, for example, aggregating with respect to plot boundaries. We discuss how the building groups can be visualised in a map by presenting a method of generating customised geometries for each group. Finally, we present a visualisation of both specific heat demand (in kWh/(m2*a)) and total heat demand (in kWh/a) in one and the same map. This aids the analysis of more complex questions involving energy efficiency and heat supply

Analysis of Analog Neural Network Model with CMOS Multipliers

The analog neural networks have some very useful advantages in comparison with digital neural network, but recent implementation of discrete elements gives not the possibility for realizing completely these advantages. The reason of this is the great variations of discrete semiconductors characteristics. The VLSI implementation of neural network algorithm is a new direction of analog neural network developments and applications. Analog design can be very difficult because of need to compensate the variations in manufacturing, in temperature, etc. It is necessary to study the characteristics and effectiveness of this implementation. In this article the parameter variation influence over analog neural network behavior has been investigated

INVESTIGATING THE POSSIBILITY OF ALLOYING AN ALLOY ALSI25CU5CR WITH CO, CR AND MO USING METAL POWDER

A base aluminium-silicon alloy AlSi25Cu5Cr was used to investigate the possibility of alloying aluminium alloys with hard-to-melt elements. The alloying elements Co, Cr and Mo were introduced into the melt using metal powder from a hard-melting dental cobalt-chromium-molybdenum alloy. The metal powder was packed in aluminium foil and introduced into the melt of the studied alloy at a temperature of 810º C. After alloying and mechanical stirring of the melt, it stood for 30 min. at a temperature, raised to 850º C and experimental castings were cast from it. After spectral analysis, the degree of absorption of the alloying elements by the aluminium melt was determined. The structure and mechanical properties of the thus obtained alloy were investigated

INVESTIGATION OF THE INFLUENCE OF THE MODIFIERS P, SR, TI AND COMBINATIONS OF THEM ON THE STRUCTURE AND MECHANICAL PROPERTIES OF ALSI25 ALLOY

The most commonly used elements to modify primary silicon crystals in the structure of hypereutectic aluminum-silicon alloys are phosphorus and sulfur. Phosphorus has been shown to have the highest coefficient of modification with respect to the primary silicon and is therefore a preferred modifier. There are also data on the positive effect of the modifiers Sb, Sr, Ti, and B on the silicon crystals in the structure of this type of alloys. The influence of the modifiers phosphorus, strontium, titanium and combinations of them on the size and shape of both the primary silicon crystals and the silicon crystals in the composition of the eutectic of the AlSi25 alloy has been studied in this work. Mechanical tests have been performed to determine both the strength and the plastic parameters of the investigated alloy (in unmodified and modified state). The classic for this type of alloys modifier - phosphorus - has been introduced into the melt by the ligature CuP10. Strontium has been introduced by the ligature AlSr10, and titanium - by the ligature AlTi5B1, the two ligatures in the form of rods. The investigated alloy has also been modified by combinations of the used modifiers: phosphorus and strontium, phosphorus and titanium.The influence of the used modifiers on the structure and mechanical properties of AlSi25 alloy has been discussed

A STUDY ON THE SELECTIVITY AND EFFICIENCY OF A GROUP OF HERBICIDES IN "DUNAVIYA" WHEAT VARIETY

In the experimental field of the Institute of Agriculture and Seed Science "Obraztsov Chiflik", Ruse, in 2017 - 2018, a study was conducted to determine the reaction of "Dunaviya" wheat variety, treated with herbicides for foliar fertilization at optimal and double doses - metasurfuron - methyl, fenoxaprop-P-ethyl, 2.4 amine salt. They did not have negative effects on the plants. Regarding destroyed weeds, all the three tested vegetation herbicides (metasurfuron - methyl, fenoxaprop-P-ethyl and 2.4 amine salt), applied at optimal and increased doses, showed high herbicidal efficiency against annual cereal and deciduous weeds. The use of metasurfuron - methyl, fenoxaprop-P-ethyl and 2.4 amine salt herbicides led to higher grain yield, compared to the untreated control