Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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Valuation of costs and change in returns of seedling technology and shallot planting distance: A case study in Grobogan Regency, Central Java, Indonesia
Get PDFThe increasing rate of shallot production of Central Java Province for the last ten years was lower than the national rate, indicated the need for new technology development. The study aims to determine the economic feasibility of the newly seedling planting technique in three planting distances (10 x 10 cm, 10 x 15 cm, and 15 x 15 cm). In that case, farmers use seed bulbs. The research was carried out in Padang Village, Tanggungharjo Subdistrict, Grobogan Regency, from August to October 2018. Financial analysis, consisting of BCR, MBCR, break-even point of both production and price, and competitive advantage of the techniques were analyzed. The results showed that the newly seedling technologies and planting distance were able to increase the productivity of shallots ranging from 12,685 to 21,088 kg. At the price of shallot bulbs at IDR 10,000 per kg, 10x10 cm planting distance resulted in the highest profit (IDR 180,790,100/ha). It was much higher compared to the farmers\u27 technology (IDR 9,299,000/ha). Based on break-even point analysis, seedling planting technology has a tolerance limit of production and prices decreasing between 67.24% to 71.44% compared to existing technology (16.03%). Seedling planting technology has a competitive advantage with a net profit ratio of 13.76 to 19.44 and a minimum selling price of IDR 3,239 to IDR 3,622 to obtain the same profit as existing technology. Thus, the technology of planting shallot seedlings at a spacing of 10 x 10 cm is recommended to increase the production and profits of shallot farming
Designing a passive-cooling, sustainable windcatcher in hot, dry area
Get PDFThis research article presents possibility of designing a sustainable windcatcher within the concept of earth-"air heat exchange" (EAHE) natural ventilation and passive cooling in hot, dry climate (Baghdad city) and to examine the impact of increasing area of the windcatcher and movement of air through buried pipe that end inside the building, and it is used for natural air movement the building is located in Baghdad. An experimental device was assigned to determine the temperature at different points during the airway that appeared from the introduction of an airflow, measured in July 2019. The results were compared with a computer simulation program (Trnsys 16), the presence of similarities was confirmed. To improve performance heat exchange (EAHE), various variables were simulated, including tube length, diameter, vertical path length, and burial depth. The heat exchange has proven important in a hot, dry climate, and passive cooling one of the most acceptable concepts and it\u27s economical too. The proposed design achieves thermal comfort and natural ventilation for a sustainable building and a source of renewable energy
Green wall design to mitigate highway pollution
Get PDFRecent studies showed that Baghdad City suffers from highly polluted environment. The enormous traffic congestion and highly number of vehicles, especially during peak hours, is the main source of this pollution. This study is focused on stopping this deterioration by suggesting a green infrastructure to the one of main arterial road of the city (Mohamed Al-Qasim Expressway). The amount of pollutants resulted from traffic fleet have been estimated. It was found that the level of pollution is exceeded the acceptable levels. A combination of vegetation (trees) and green wall (shrubs) has been proposed for designing the green infrastructure for a selected section. Three types of trees namely: Neem tree, Ficus benjamina and Conocarpus have been selected after review many types that can be used for this purpose and resist the extreme hot weather. Two types of shrubs: Myrtus communis and Dodonaea viscosa were proposed due to their suitability for this function of filtering the particulate matters. The maximum ideal annual amount of CO2 sequestration for 1km of trees planted on road sides and median was about 43.2, 10.5, and 9.25 Tonne for the Neem tree, Ficus benjamina, and Conocarpus, respectively
Hydrotreating unit models based on statistical and fuzzy information
Get PDFThis paper presents the results of mathematical models’ development for hydrotreating reactor, stripping соlumn, absorbers and hydrotreating furnace which are basic units of hydrotreating block in catalytic reforming unit. Since these objects of modeling in reforming unit of Atyrau refinery operate in conditions of insufficiency and fuzziness of the initial information, their mathematical models are developed on the basis of a systematic approach, using available information of different nature (experimental-statistical data, fuzzy information from the experts), with appropriate methods of construction for mathematical models. Mathematical models, describing the dependence of the production output from the hydrotreating reactor, columns and furnace, are designed as a nonlinear regression models based on experimental-statistical data. Whereas models, evaluating the quality indicators of generated products from the hydrotreating reactor and columns, i.e., hydrogenation, hydrogen-containing and hydrocarbon-containing gases are built based on fuzzy information from specialists-experts in the form of fuzzy multiple regression equations. We have plotted the graph for the dependence of hydrogenation products output on the temperature in the hydrotreating reactor. To describe the dependence of the optimum temperature value in hydrotreating process on raw material quality, a linguistic model is designed based on compositional rules of inference and fuzzy information. Membership functions of fuzzy parameters are constructed for linguistic models
Management of corporate responsibility in the business environment: Socio-psychological aspect
Get PDFThe article considers the methodological approach and recommends practical provisions for the management of corporate responsibility of professionals in the business environment, taking into account the socio-psychological components that ensure the trajectory of stable professional development in the food market. It is substantiated that the trajectory of professional stability with a corporate consciousness of development is not a process of continuous action, but a consistent and purposeful project with a certain result, limited in time and resources. Dividing activities into a series of projects allows specifying goals, increasing the accuracy of plans and forecasts. Social trust becomes a certain basis for understanding social relations and responsibility for the process of integration of professional development and stable business activities in the market. The psychological support of stable professional development of employees of the enterprise with corporate responsibility of the business environment is developed. Guidelines and standardized norms of the management at “professional mobility – professional stability” are defined. Signs of intensification of professional development of specialists of the enterprise on the scale of psychological well-being are interpreted. Empirical procedures for qualitative and quantitative analysis of the integral components of the professional potential of employees of the enterprise with a certain level management of corporate responsibility in the business environment are presented. A methodical approach to determining the level of influence of the social component on the corporate responsibility of professional specialists of the enterprise in the market business environment is proposed
Obtaining a composite material based on quartz woven filler and pyrolysis matrix of organosilicon resin
Get PDFThe relevance of the study is conditioned by the fact that the most popular and irreplaceable materials that have found wide application in the aerospace industry are composites based on quartz materials. These materials are distinguished by their high mechanical and electrical strength, chemical and corrosion resistance. In this regard, it is of interest to obtain a composite material that combines a low specific gravity, processability of polymers, and thermal stability of ceramics. The aim of this work was to study the effect of the temperature of thermal oxidative destruction of a polymer binder, which is a semi-finished product of a pyrolysis matrix, on the electrophysical parameters of a composite material. The paper investigates a composite material based on woven quartz material with a pyrolysis matrix of an organosilicon binder and functional additives. This composite was considered as a material for creating an electric rocket engine chamber. Thermogravimetric analysis was used to evaluate the effect of the temperature of thermooxidative degradation of the polymer binder on the electro-physical parameters of the obtained material. The tests were carried out according to standard test methods on an Instron 5969 universal testing machine with Bluehill software until the samples failed. In the course of the study, it was found that the processes that occur up to 400°C are mainly associated with the course of the reaction for non-entered functional groups, the telomerisation reaction, intramolecular rearrangement of macromolecules and the removal of low-boiling substances. According to the results of the study, the obtained characteristics of the test material turned out to be suitable for its use in structural elements of electric propulsion engines
Simulation of a control system for the accident-free flight of three UAVs in the V formation in a heterogeneous environment
Get PDFModern methods of creating groups of unmanned aerial vehicles (UAVs) require the use of complex (generalised) criteria, introduced mathematical models in the process of optimising the parameters of the UAV components. Such models should simulate the operation of an unmanned aerial vehicle when performing its task. The study considers strategies for diverging dangerously approaching UAVs using areas of dangerous courses and speeds. First, procedures were performed to establish the dangerous course areas of one UAV and the speeds of the second UAV, taking into account their ratio of speeds and dynamics. The areas for the case of UAV with insignificant transients of changes in courses and speeds, the duration of which can be neglected, is provided. In addition, procedures of the establishment of areas of dangerous courses of one UAV and the speeds of the second UAV with significant inertia are considered. Methods of the establishment of areas in the event of a decrease in the speed of the second UAV by active or passive braking are developed. Examples of choosing a safe manoeuvre in a situation of dangerous convergence of two UAVs are given. A more complex situation of approaching two UAVs in the presence of an interfering third UAV is also considered, and a method for choosing a safe manoeuvre is proposed, taking into account the interfering third UAV. Moreover, for such a situation, two alternative procedures for choosing a safe manoeuvre are proposed. The result of solving this problem was a method for establishing the area of dangerous courses and speeds of UAVs, taking into account the inertia-braking characteristics when determining a safe joint divergence manoeuvre taking into account the presence of a third UAV that provides interference
Design and implementation of PSO/ABC tunned PID controller for Buck converters
Get PDFIn the recent years, Buck converters have been widely involved in a variety of the everyday applications such as smartphones and PCs. Buck converters can provide better and steadier performance when integrating a control system in the design. Therefore, it is interesting to work on this integration and gain the required efficiency in term of the gained voltage. In this paper, PID controller is adopted to control the output voltage of the Buck converter. An optimization is achieved on the performance of the Buck converter using two bio-inspired algorithms namely, Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC). The voltage controlled Buck converter system is simulated using Matlab environment to validate the proposed PID controller system. In this study, the voltage regulation process of Buck converter is investigated based on many working disturbances such as the change in the supply voltage, reference voltage, and load resistance in order to verify the robustness of the proposed PID controller. Finally, the feedabck voltage control system of the Buck converter is implemented experimentaly in real-time to validatde the simulated PID controller
A new labour safety in construction management based on artificial intelligence
Get PDFConstruction management is considered a very important field in civil engineering. A lot of tracks had in civil engineering that achieve construction management, such as risk, time, material and labour. One of the best tracks that achieve construction is risk management in modern civil applications. Moreover, this vital track is connected directly with labour life for this it is a very important issue. Hence, the main cause of death and injuries of labour during working is decline safety measures and sometimes building control management has been utilising traditional risk monitoring. It is considered a major concern of civil engineers. In this paper, a new labour safety system in construction management is proposed to provide a safe environment. However, risk management is designed that based on the fall detection approach of labour during working or walking at high-rise buildings. In other words, online monitoring risk is proposed to support and enhance construction management in civil engineering. The proposed system will play an important role by notifying the console panel on time that helps to reduce the death rate. However, the detection system is heavily based on real pictures received from the cameras. These cameras will be distributed randomly in the building area. These pictures will be analysed at the control panel in construction management for civil engineering. In other words, the decision-maker is strongly dependent on received pictures from these cameras. According to the experimental results, outstanding results is achieved from risk monitoring in construction management. 
Optical performance assessment of a handmade prototype of linear Fresnel concentrator
Get PDFThis article aims to evaluate the optical behavior of a small handmade prototype of a linear Fresnel concentrator (LFC). The system was developed and tested as a water heater and steam generator at the Unidades Tecnológicas de Santander university, located in Bucaramanga, Colombia. Optical factors of the thermo-solar system studied were taken into account, such as concentration ratio and optical efficiency relationships. The Monte Carlo ray tracing method (MCRT) was carried out as an optical evaluation tool through the application of the free access software "SolTrace" and "TONATIUH" to later contrast the results obtained with both simulation tools. At the same time, the performance output from the simulations was compared with the optical performance of the experiments previously carried out with the device LFC, with the aim of evaluating the reliability and accuracy of the analysis developed through the MCRT methodology. The results obtained showed that the number of reflective mirrors or area of reflection has a direct impact on the optical efficiency of the prototype, where it is evidenced that there is a higher optical efficiency and a higher CR when the reflection area is larger. Similarly, direct solar radiation (DNI) has the same trend, showing that higher levels of direct solar radiation (DNI) increase optical efficiency. Finally, it was observed that the variation in the number of rays used in the simulations (10,000,000 and 5,000,000) does not influence the optical performance of the device