Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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Urban regeneration through post-war reconstruction: Reclaiming the urban identity of the old city of Mosul
Full text linkThis paper attempts to shed light on conserving local architectural heritage through the redevelopment and reconstruction of a city suffering from post-war devastation, while maintaining local identity. The city of Mosul is the 2nd largest city in Iraq, with a population of 1.8 million in the year 2014 before the ISIS occupation of the area. This study intents to recommend urban regeneration strategies, to be taken upon during the redevelopment of the old city of Mosul. A set of strategies that may ensure the preservation of the urban identity of the area, while redeveloping and coping with today’s environmental, socio-economic and political changes. A thorough theoretical analysis was carried out by the researchers to conclude a set of indicators of urban regeneration strategies to ensure memory, identity and development. The recommendations emphasized on the integration of the new designs with the old urban fabric, also harmonizing the physical environment with the original buildings whether withstanding or destructed. They also referred to the importance of buildings with historical and symbolic values and their role in reclaiming the urban identity and promoting the sense of belonging
Reviving urban spaces through tactical urbanism in baghdad: Five common tactics
Full text linkThis research investigates the socio-spatial causes and consequences of tactical urbanism practices in Baghdad. It attempts to identify the main creators of these practices and their motivations. It recognizes five common practices of tactical urbanism in Baghdad, public art, pop-up rest areas, pavement plazas, guerrilla gardening, and open streets. This research argues that the applications of tactical urbanism in Baghdad could revive urban spaces and positively impact local communities, and that it could have various implications for urban policies. This article examines evidence from fieldwork and interviews with individuals involved in tactical urbanism projects. It also employs a questionnaire which addresses the opinions of individuals in the profession of architecture and urban design regarding the impact of tactical urbanism
Homeostaticity of energy systems: How to engineer grid flexibility and why should electric utilities care
Full text linkToday’s power generation and distribution industry is being faced with a number of issues, from violent weather phenomena to earthquakes, fires and landslides; including acts of arson, terrorism and vandalism, all of which pose serious concerns for the sustainability of the distribution and supply of electricity. Electric utilities like ENEL are cognizant of this fact and know they must take action. Moreover, they are required by law to be prepared and act proactively to prevent service disruption, by responding to such challenges rapidly and effectively so as to preserve stability and continuity of operation. Homeostaticity of energy systems seeks just that: to bring about a rapid, effective and efficient state of equilibrium between energy supply and expenditure at all times, whatever the circumstances, to preserve stability of systems operation. The paper presents a prescriptive energy homeostaticity model being considered by ENEL as a means to further the incorporation of renewables in the electricity generation and distribution industry. The aim is to enhance control and energy management systems in distributed generation installations tied to the grid for urban and rural communities, in order to complement and diversify their electric power distribution services. The theoretical groundwork underlying the subject as well as other relevant contextual factors are also discussed and simulation results are presented under different tariff scenarios, and energy storage alternatives, in order to compare the proposed model with the actual case. Energy storage (ES) is found to be of paramount importance in the overall analysis of the results as it enhances and reinforces thriftiness on energy consumption
Analytical unequal-spreading factor DCSK: A robust chaotic modulation framework for noisy channels
Full text linkIn the present paper, an Analytical Unequal-Spreading Factor Differential Chaotic Shift Keying (USF-DCSK) modulation scheme is proposed to enhance the reliability and energy efficiency of chaotic communications in noisy and fading propagation environments. The proposed system contains an analytical beta-allocation function that adjusts the spreading factor dynamically both as a function of the instantaneous signal-to-noise ratio (SNR) and the perceptual significance of each bit-plane. This adaptive allocation balances robustness and power efficiency, providing improved protection for perceptually important bits while simultaneously reducing redundancy in good channel conditions. Simulation trials run over additive white Gaussian noise (AWGN) and Rayleigh fading channels support the model efficiency and show the maximum mean-square-error (MSE) reduction of 94% and 12 dB peak signal-to-noise ratio (PSNR) improvement in the AWGN case and a consistent 36% MSE reduction and approximately 1.5 dB PSNR improvement in the Rayleigh fading channel. Besides performance improvement, the modulator itself provides an additional degree of data confidentiality by its non-uniform chaotic spread, which makes statistical interception significantly harder than without this overhead. Furthermore, it is found in the investigation that wireless sensor networks (WSNs) and wireless visual sensor networks (WVSNs) are especially favorable application domains for the proposed modulation framework. These networks are mainly battery powered, so the use of energy-efficient modulation is the key to increasing the lifetime of nodes; additionally, because they are static or semi-static networks, it is possible to make approximate predictions of the channel conditions at the transmitter, thus allowing the practical and cost-effective implementation of adaptive chaotic spreading without the need for frequent feedback. The results validate the idea that the USF-DCSK model provides a theoretically valid and practical solution for robust, energy-aware, and perceptually optimized wireless multimedia communication solutions
Perfecting of mathematical tools for forecasting the country development vectors on the basis of economic and demographic parameters system analysis
Full text linkUnder the conditions of activeglobe community activitiesaimed atsolving systemic problems in socio-economic development the scientific and practical interest to the study of demo-economic processes applying mathematical tools increases objectively. This issue is especially actual for Ukraine, which hadeconomic conditions similar to many EU countriec, but got unsatisfactory results in the market economy functioning. Therefore, it is the task of paramount importance to establish cause-effect relationships between key demo-economic indicators of Ukraine and a country with a set of similar conditions of development (Poland) to adjust the strategic goals of sustainable development of Ukraine towards the meeting of EU demographic standards.The results of the analysis of the demo-economic situation in Ukraine and Poland in 2000-2017 revealed opposite trends in development. The human factor proved to be a strong component of development for both countries. The methodical approach to the assessment of the regional level of human development, based on the improvement of the mathematical tools for forecasting the development vectors of the country, is proposed. It is based on the grouping of country regions according to certain demographic parameters. Common and peculiarissues of human development indifferent regions of Ukraine are systematized upon the basis of clusterization. The established regularities of demo-economic development of entire Ukraine and regional features, the levers of state regulation of human potential formation of Poland were taken into account and laid as the basis of scientific and practical recommendations for adjusting the Strategy of Sustainable Development of Ukraine
Modelling tax consciousness evaluation in the context of economic development uncertainty
Full text linkThe aim of this study is to compare a finite set of subjects of taxation by means of evaluating their relative importance by tax consciousness levels using a scale in T. Saaty’s analytic hierarchy process. As a result, the highest value is obtained for large taxpayers, followed by the government, then controlling bodies, and the lowest value is obtained for small taxpayers. The values of the cognitive component for all subjects of taxation are high due to the high accessibility of education, lifelong learning, and development of advisory functions of controlling bodies. Middle-high values of emotional and volitional component are determined by the subjective nature of managerial decision-making and the degree of trust in government and taxation system. Low values of the behavioral component are determined by the subject’s socio-economic role which affects the availability of tax behavior alternatives and their risks in a certain area of activity. It has been proved that there are no standard values for the structural elements and tax consciousness as a whole as they simultaneously represent the cause and effect of imbalances in the functioning and development of the socio-economic system of the country
Modelling multifractal properties of cryptocurrency market
Full text linkThe paper focuses on the study of the effect of long memory and the analysis of the multifractal properties of the time series of the most capitalized cryptocurrencies for the period from 2010 to 2018. To do this, the Hurst exponent is calculated by both R/S analysis and the Detrended Fluctuation Analysis being more stable in the case of non-stationary time series. Our results show that time series of cryptocurrencies to be persistent during almost the whole study period that do not allow accepting the hypothesis concerning the efficiency of the cryptocurrency market. We also found that (i) time series became anti-persistent during the periods of market crisis phenomena and turbulence; (ii) the Hurst exponents showed significant fluctuations about the value of 0.5. In addition, we conduct a multifractal analysis of cryptocurrency time series that allows us to assess the state and stability of the market.The calculated spectrum of multifractality shows that the cryptocurrency market comes out of a crisis state, since the width of the multifractality spectrum has the maximum value for all cryptocurrencies
The marketing channel structure: A case of chemical industry company
Full text linkThe subject of the research are peculiarities of marketing channels structure of industrial company that operates in the chemical industry. The main research activities were focused on the basis of Ukrainian power and chemical association PJSC “Sumykhimprom”. The methodical approach of the study is based on analytic and descriptive approach and is aimed at providing a case study. Thus, the goal of the study is to provide an empirical study on auditing the company’s marketing channel system and on identifying the current status of marketing channels members. The study suggests that marketing channels function effectively when taking into account the interests of all marketing channel members (manufacturer, intermediaries, end users). The choice of a marketing channel depends on the company\u27s planned sales and profits, available resources, positioning strategies, the intensity of geographical coverage, industry specifics. Marketing channels of PJSC “Sumykhimprom” are grouped in terms of distribution geography into three groups: 1) distributors in the European market; 2) distributors in Ukrainian market and in neighboring countries; 3) distributors in the market of distant foreign countries. The research results allow to form the optimal structure of marketing channels, which simultaneously takes into account the interests of the manufacturer, as well as the consumer. Recommendations to transform the marketing channels structure of PJSC “Sumykhimprom” are formed
Competitiveness of the national economy: current aspects of management
Full text linkcompetitiveness depending on the hierarchy of the object of study in the national economic system, as well as to highlight the level of the research of the object of competitiveness taking into account the functioning of the business entity, to identify the pattern between the competitiveness of the national economy of the country and its subjects - enterprises. The considered approach to the structuring of research activities of an enterprise as an economic object, allows you to select the internal and external competitiveness of the enterprise depending on the level of its assessment, which requires the formation of a system of indicators for its assessment. In the context of the study, another aspect of the analysis of the essence of competitiveness is the study of existing methods of its assessment at the enterprise, and as a result of suggestions for improvements, a methodical approach to the analysis of the competitiveness of an industrial enterprise, taking into account factors influencing the external environment in which it operates - CEF analysis allows you to conduct a comprehensive analysis of the competence and efficiency of the enterprise with the help of a system of performance indicators, to identify reserves and develop recommendations to ensure its competitiveness. Effective management of enterprise competitiveness is possible through the improvement of the structure of the organizational and economic system of managing it, described and improved by us
Adaptive hybrid technique for face recognition
Full text linkOne of the most important biometric features for personal identification is the face. In current paper, a new method of face verification upon on singular value decomposition (SVD) and standard deviation (SD) would be described. Due to many variations in real-life such as pose, illumination, or facial expression, there would be difficulty of face recognition. It should be mentioned that there are many approaches for face recognition, however, there is no one could be considered as the most suitable for many situations. One of the methods used is Singular value vector for an image detecting, but the drawback of this approach is the low rate of recognition, where one scale singular value vector is used for face acknowledgment. There an algorithm has been developed to expand the rate of the recognition. In this paper, an approach has been proposed to associate two feature sets obtained from SVD and SD method. It has noticed a good recognition rate could be obtained from the experimental results, where approximately more that 97.5% recognition rate has obtained on the ORL data base. The results from current proposed method have matched with some techniques and it has shown that this method is better than the existing approaches. An extensive experiment has demonstrated not only better performance, but it offers a great likely to achieve equivalent performance to other categories of state-of-the-art method