This research was conducted to determine the effect of increasing temperature on the compressive strength of geopolymer concrete. The specimens used in this study is cylindrical concrete with a diameter of 150 mm and a height of 300 mm and the design compressive strength, f'c is 30 MPa. The variable in this study was the molarity of the NaOH solution in the geopolymer with variations of 4M, 6M, and 8M. Before the compressive strength test, some of the specimens were burned at a temperature of 1000°C. In this study, some of the specimens are coated with fire-retardant additives on its surface. The results of this study indicate that the 8M NaoH geopolymer concrete with fire-retardant coating shows highest residual compressive strength at 54.7 %. It can be stated that the molarity value of NaOH and fire-retardant additive coating will be able to provide geopolymer concrete structure resistance to elevated temperature due to fire accident.

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Higher energy absorption efficiency and better crashworthiness performance are always the primary goals of researchers. This paper aims to study the bending collapse bahaviour of polygonal cross-sectional thin wall beam (TWB) under quasi statics bending. TWB are commonly used as energy absorbers in automobiles due to their light weight and high energy absorption capacity. TWB that is circular or square is frequently used inside vehicle doors. This beam deforms and absorbs the maximum impact energy in the event of a side collision than other components of doors. The crashworthiness of polygonal cross-section TWBs subjected to bending load was investigated using numerical simulations, and they were compared to the corresponding circular and square cross-section TWBs. In this work polygonal TWB ranging from the pentagon to the dodecagon are considered for analysis. To evaluate the bending collapse performance of beams, specific energy absorption and crash force efficiency crashworthiness indicators are used. Finite element simulations were conducted in ABAQUS explicit dynamic software, and all polygon plastic hinges and flattening patterns were examined. The results show that heptagon, octagon, and nonagon cross-section TWB outdo square and circular TWB in crashworthiness performance.

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The purpose of this research is to use a factorial experimental design to disinfect total coliform bacteria present in treated urban wastewater using solar disinfection processes. The multilevel factorial design (4321) was used to study the influence of factors and interaction between factors on total coliform removal. The four factors considered were Solar energy, Volume of Sample, Exposure time and type of reactor at two markedly different levels: solar energy (1100,1300, 1500 and 1700 W.h/m2), volume of sample (0.2,0.5,1 and2L), exposure time (0.5,1,2 and 3 hrs.) and type of reactor (Open air and Solar reactor). The experimental results of the solar disinfection process were analyzed statistically using the student’s t -test, analysis of variance, F -test, and lack of fit to define the most important process variables affecting total coliform removal. It is observed that the type of reactor is the variable with the greatest influence on the response factor (percentage of total coliform removed), although other variables also have a significant influence. Furthermore, a mathematical model (regression equation) has been obtained taking into account the influence of variables of total coliform removal. The model adequately describes the total coliform removal from treated urban wastewater using solar disinfection.

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The disruption caused due to the current pandemic situation in the areas of supply chains, tourism, aviation, hospitality, sports and fashion is enormous. This effect is more visible in manufacturing sector especially in fashion, appeal and garment industry. This resulted in the companies emphasizing on the effective utilization of resources and enhanced productivity. Although, the concept of lean manufacturing, value stream mapping (VSM), Jidoka, Kaizen, 5S, Kanban, Poka Yoke, line balancing and many more are available in the literature, that can enhance productivity, the incorporation of data analytics and software-based simulations as a method to support decision making in real time production activity to enhance productivity is the need of the hour. The aim of the research paper is to develop a framework of model driven decision support system (MD-DSS) where real time data is fed to the system and data simulation and communication technologies help in improving the productivity of the manufacturing process. An empirical study was conducted at AL Apparel Manufacturing PLC, Addis Ababa (Ethiopia) garment manufacturing facility to demonstrate the proposed model. Data is collected through observations, document studies, and time study measurements for skimmer trouser having 34 operations. The assembly line is balanced using discrete event Arena simulation program. The results indicated that the proposed model has high line efficiency and increased productivity.

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An increase in the carbon content in cast iron and steel during melting is obtained by means of adding carbonaceous materials–carburizers (carburizing agents) to furnace charge [1-5]. To optimize the fastest and complete carbon recovery a carburizer should have a minimal level of impurities and low-ash content. As the ash content of the carburizer decreases, the amount of bottom slag also decreases, which, in turn, increases the durability of the furnace lining. To avoid excessive sulfur saturation of cast iron, the carburizer must contain a minimum amount of sulfur [6, 7]. Currently, coals and natural graphites as carburizers find wide application [1–5]. In comparison with other carbonaceous materials, natural graphites are currently of limited use because of their high sulphur content, which is presented by pyrite (polysulfide form) or available in the sulfide form presented by inclusions and sinters of 2×1 mm in size. Due to the fact that the graphite raw material was formed of sapropelic coals, the mineral components are unevenly distributed within the bulk of the ore in the form of attachments to the main carbon material and micron-sized siltstone. This explains the position of the process men, based on the fact that graphite ore is difficult to enrich, including sulfur [8, 9]. The efficiency of removing sulfur compounds from graphite depends on numerous factors, the main ones being the physical and chemical characteristics of sulfides (crystal structure, stoichiometric composition, magnetic susceptibility, etc.); the total content and ratio of various types of sulfur in graphite; the nature and form of inclusions of sulfides in graphite; the distribution of sulfur compounds according to size classes; the degree of disclosure of iron sulfides attachments to graphite during grinding, crushing; the accuracy of separation in enrichment processes; applied equipment and desulfurization technology [10]. The objective of this paper is to develop technologies for graphite desulfurization, which allows reducing the sulfur content to 0.05 %.

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Building effective systems for information exchange, compression and storage of information requires the use of reliable codes with certain properties that can be easily implemented in information systems. The paper considers a mathematical model based on a class of continuous functions with fractal properties defined by a three-character representation (coding). This mathematical model is used for encoding of digital data source. For the mathematical apparatus, the theorem that prove the uniqueness of the functional equation solution under initial conditions is offered, which in turn allows to construct an algorithm for encoding and decoding information. There are also examples of applications of this apparatus, which in particular have the property of decoding uniformity. The proposed model allows to develop a new fractal coding technology for efficient transmission and processing of data over communication channels in geographic information systems.

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The article provides information on the state of the environmental load, which has a significant impact on life and the environment in the industrial region of the south of the Republic of Kazakhstan. The results of the analysis and examination of the standards of maximum permissible emissions of one of the phosphorus enterprises, including the technological chain “raw material warehouse, crushing and drying department, preparation of raw materials, technological redistribution are given. The materials are presented that substantiate the need to optimize the process of reducing the environmental load and improving the living conditions in the production of fertilizer mixture, in connection with the need for the utilization and processing of various natural and man-made raw materials. The analysis and calculations of the identified parameters affecting the dust and gas emissions formed during the heat treatment of raw materials are presented, with the development of a functional dependence of the dust content reduction indicators.

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The paper considers the field of software engineering related to the parametric synthesis of neural networks based on an evolutionary approach and its application in the diagnosis of diabetes. As a result of the research, an intelligent decision support system for diagnosing diabetes was developed, which is based on machine learning models. The model of parametric optimization of the neural network due to the use of genetic algorithm and particle swarm method is implemented. A modified genetic method for optimizing neural network parameters to solve the problem of predicting the risk of diabetes has been developed. Modification of a simple genetic algorithm, which is implemented as part of the project. allows you to speed up the selection of learning parameters of neural networks, and increase the resulting accuracy compared to the basic version of a simple genetic algorithm, by modifying the mutation operator, as well as a changed approach to the selection of individuals for crossing. The developed model is intended for use in the field of medical care and allows to determine with some accuracy the presence of the risk of diabetes in patients by clinical indicators of health. The result of this model is to reduce the likelihood of a doctor's error, increase the doctor's confidence in the decision made in the diagnosis and more lives saved, by making a correct and timely diagnosis. The developed model is intended for use in the field of medical care and allows to determine with some accuracy the presence of the risk of diabetes in patients by clinical indicators of health. The result of this model is to reduce the likelihood of a doctor's error, increase the doctor's confidence in the decision when making a diagnosis and more lives saved, by making a correct and timely diagnosis. The developed model is intended for use in the field of medical care and allows to determine with some accuracy the presence of the risk of diabetes in patients by clinical indicators of health. The result of this model is to reduce the likelihood of a doctor's error, increase the doctor's confidence in the decision when making a diagnosis and more lives saved, by making a correct and timely diagnosis.

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The generalize distribution from a classical distribution is performed by adding more parameters to the distribution that makes the distribution more flexible in analyzing empirical data and able to adjust the shape of empirical data. The generalization of this distribution produces a Beta Generalized of the first kind distribution or a GB2 distribution with three and four parameters. This paper will discuss the GB2 distribution with four parameters namely a, p and q as shape parameters while parameter b is the scale parameter. In statistical inference, especially parameter estimation, is needed in analyzing empirical data with this distribution. Obviously the estimation results obtained are expected to be a sound estimator, namely to meet the criteria of unbiasedness and minimum variance. The estimation results of the GB2 distribution parameters through simulations using the methods of moment, the Maximum Likelihood Estimation, and the Probability Weighted Moment. Based on the results from the simulation of the three estimation methods that the estimation of parameters by using the Maximum Likelihood Estimation is better than the method of Probability Weighted Moment and the method of moment where in a larger sample size gives a smaller bias and MSE value.

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Transportation modeling in the concept of movement generation is connecting one characteristic with other characteristics. Such as socio-economic characteristics with movement behavior from one zone to another. The transportation system is a form of interrelatedness between actors within its scope such as users, goods, infrastructure and facilities together, both natural and planned. This system aims to coordinate movement with components that use the media in a measurable transportation process. Formulate and evaluate transportation infrastructure facilities and traffic signs at intersections so that the right way to make decisions is based on the criteria set out in the research methodology. From the five research points and based on the SWOT analysis, the selected criteria with factors were obtained. that the Bogor city government and the Bogor district government have a Strength-Opportunity (SO) strategy of 7,156 so that this most powerful concept is the driving force for establishing a good city concept, that it can optimize the development of transportation infrastructure and the TULLAK area to meet transportation needs between regions and support regional development . There is a synchronization of the transportation sector in regional development and economic development and the development of existing transportation networks in the area based on the potential geographic location and natural resources of the city of Bogor and Bogor district by looking at opportunities from the transportation sector and tourism sector.

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Information is provided on the waste of mining and manufacturing enterprises formed during the extraction, preparation and processing of raw materials for the target products. In particular, off-balance, substandard P2O5 content, phosphate-siliceous and carbonate - siliceous phosphate ores of the Karatau basin. Materials on phosphogypsum related to the technological costs of obtaining extraction phosphoric acid (EPA) by the method of leaching sulfuric acid phosphorus by the dehydrate method are presented. The concepts of chemistry occurring in the electro thermal, in the presence of a coolant and a flux, as well as chemical, with the use of H2SO4, methods of extracting phosphorus from phosphorus-containing raw materials are given. The data of differential thermal analysis of phosphogypsum are shown. The mineralogical and chemical compositions of phosphogypsum, the main technogenic waste of the process of the dihydrate method of obtaining EPA, which in the process of storage in dump dumps can lead to a violation of the ecological equilibrium state of industrial regions in the form of dust-gaseous substances, are presented.

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Long distance power transfer is one of the major problems of renewable energy source located in far-off and secluded areas from the major load center. This is due to the increase in power loss along the transmission caused by the length of the transmission medium used for the power transfer of such distances. LTSpice was used to simulate the circuit and the results were plotted using MATLAB in order to conjure the result of the trials with respect to distance. Having 10 trials, the distance increments by 25 where the resulting voltage is directly proportional to the increase in each trial. The present study aims to study and develop an external cable compensator in minimizing the voltage loss for the supply of power source for CCTV cameras.

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This work shows for the first time the structure of Lake Bolshoye Bele bottom sediments, one of the lakes investigated as a part of grant ?671-2020-0049 in in the sphere of scientific activities. These works were carried out to detect bottom sediments in lakes and for further sampling of core columns for reconstruction paleoclimatic changes based on these sediments. The results were obtained using the high-resolution seismoacoustic method (single-channel 3 kHz sub-bottom profiler) and coring campaign (gravity corer). This data set enables detailed characterization of the sedimentary subsurface. This paper focused on the central part of the Lake Bolshoye Bele, in which significant thickness of sediments up to 20 m was found, which was divided into 3 seismic facies.

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