The need to decrease energy use represents a challenge particularly in developing countries, including Kosovo, considering the unsustainable, insufficient, and inconsistent energy supply. This contribution presents a simplified yet comprehensive approach to evaluate the energy performance improvement potential of three selected multi-family residential buildings using building energy models generated from calibrated and simplified input parameters. To this end, alternative retrofit measures were tested via a simulation-based parametric study. The energy benefit of each retrofit alternative was estimated and analyzed. Results are expected to provide valuable information towards outlining design guidelines for energy-efficient residential buildings in Kosovo.
The paper compares different metaheuristics for using heat exchangers as a benchmark to estimate the best design parameter values using optimization efficient algorithms. Many MATLAB algorithms are used in this study. Also, an engineering equation solver, which is commercial software, is used to solve the issue. The design calculates three variables, which are the length, and inner and outer pipe diameter of the heat exchanger. The results showed that the best algorithms are particle swarm optimization, and when using this algorithm, the optimal design of the double pipe heat exchanger is as follows: the pipe length is 5.6734·10−1 m, the pipe inner diameter is 8.0203·10−3 m, and the pipe outer diameter is 2.2439·10−2 m.
Application of leaf extracts in alkyd extract primer (AEP) to inhibit corrosion of mild steel was compared with performance of alkyd conventional primer (ACP) containing zinc phosphate and zinc chromate as inhibitors. The investigations were carried out through Gasometric technique in 5 °C steps of temperature increase from 25 to 50 °C in 1.0 M HCl as corrodent. The AEP of 34.24 percent actives compared with ACP of 56.57 percent actives gave the same inhibition efficiencies of 76.5%. Extract primer of lower percent active compared with conventional primer were cost effective and more potent than conventional primer.
The air temperature in school buildings significantly affects the ability of students and teachers to focus on the educational process. Students usually begin to feel an increase the temperature in room. The purpose of this study is to find the limit of the temperature rise in the classroom when people no longer feel the temperature rise in the room. For this reason, several experimental measurements of indoor air parameters were carried out: air temperature, relative humidity and carbon dioxide concentration. Measured temperature differences and individual subjective ratings of audiences determined the dependence using mathematical statistics, from which can be determined the critical level of increase in air temperature at which people no longer perceive the change in air temperature.
The design of pollution-free energy recovery systems has become an important goal by researchers as renewable energy is an alternative to traditional energy that depends on fossil fuels. In this work, a multifunctional electromechanical speed bump was invented to be used on the streets to generate clean, sustainable energy by utilizing and investing the kinetic energy of vehicles passing on the roads. The current model was designed to perform three functions simultaneously.
To measure the performance of the innovative speed bump system, a (simplified) prototype was made that simulates the work of the multifunctional bump. The results showed that the proposed initial speed bump model is a promising technology that can be applied as a clean, renewable energy source that can be easily applied in crowded streets.
Multilevel inverters performance enhancement is a major topic, which has attracted the attention of most of the researchers, to evolve with newer topologies and modulation strategies. In this manuscript, two novel hybrid bidirectional multilevel inverter structures, which are suitable for bidirectional loads, are proposed. An enhancement in the voltage levels and reduction of the component count are achieved for these newly introduced structures. Modular expansion and series cascading are suggested systems for extension of the voltage levels. The prime requirement in most of the industrial drives is a controlled output. VSI fed induction motor drive satisfies this requirement. The Multicarrier PWM technique has been applied to the basic bidirectional seven level models and nine level model and its performance with induction motor as load has been analyzed for various modulation indices. The simulated results of the proposed structures are verified using MATLAB/SIMULINK platform. The characteristics such as stator current, rotor current speed and torque plots achieved as above model affirm that its performance is good. By then, the tracking time of the proposed work during reference speed change, load change and constant reference change is 0.185, 1.094 and 1.5 s. The tracking time of the VSI during reference speed change, load change and constant reference change is 0.5 s, 3.8 and 3.5 s. The tracking time of the MLI during reference speed change, load change and constant reference change is 0.2 s, 1.8 and 2 s.
Owing to their elevated absorption coefficient, superior resistance to radiation and reduced effective electron mass, gallium antimonide (GaSb) semiconductors were documented to be suitable for photovoltaic systems applications. However, they were found to suffer from low efficiency. This work has been dedicated to enhance the design of GaSb based single-junction solar cells having window and back surface field made from AlGaAsSb material. The purpose is to maximize their electrical performance by considering doping and thickness of layers as design variables. A methodology of optimization was proposed. It is based on computer aided design through simulations performed under SILVACO-ATLAS software and a numerical procedure that was developed to achieve optimal design of this particular solar cell. The approach encompasses analysis of variance and derivation of response surface models to get explicit expression of the objective function corresponding to efficiency. The obtained results have shown an efficiency which is higher than all the previous known values established in literature.
The demand for community involvement during the planning process is growing. Kosovo, to be in step with global development trends in the field of planning, has developed various projects in the name of public participation. The pilot project for the Brekoci informal settlement in Gjakova is an example of community-based planning. The purpose of this paper is to show the way of community involvement through unique methods explicitly designed for this community, as the tool “Express”, “Mark” and “Vote” and how the data obtained from these tools through spatial systems as Geographical Information System and DepthMapX, have generated the community's vision, which has resulted in the drafting of the urban regulatory plan. This plan represents a reflection of the local cultural context.
Public space is the most important place for social life, but it is also part of the identity of the local community. This is particularly true in Komló, where the mining past is still a perceptible and integral part of local identity. Petőfi Square is the central square of Komló's Kökönyös district, an urban district center that preserves the memories of its past, but has not evolved with changing needs in the city for some time. The renewal of Petőfi Square and its surroundings was an environmental architecture task that built on local values, responded to the needs of local people and helped the development of community life, and had to cope with a number of parallel demands.
The article is devoted to research of properties of the round convective air jet. The aim of this work is to establish universal graphical dependencies and empirical formulas for describing velocity and temperature fields over the entire range of development of round convective exhaust ventilation jet; development of an algorithm for solving the transcendent problem of determining the surface temperature of a heat source; introduction of velocity and temperature attenuation coefficients for round convective jet; visualization of its characteristics in the form of a 3D image; achieving reduction of metal consumption of the local exhaust ventilation system due to the overall optimization of the velocity and temperature fields of the round convective air jet.