A problem concerning improved stability of development mine workings under complicated mining and geological conditions of mines in Western Donbas has become extremely important. The tendency is the increase in coal extraction resulting in the fact that KSHPU-arched development mine workings become longer. Analysis of the state of mine workings in Western Donbas mines inclusive of the analysis of expenditures, connected with their construction, and maintenance, shows: the measures to prevent and cure the effects of floor rocks heaving, being a variety of deformation of neighbouring rock mass of mine workings, are the most labour-intensive processes while providing operational state of the mine workings. A process of a frame support bearing forcing in a floor of a mine working can be described in the form of a functional dependence between the reduced time interval of the support operation and a depth of its forcing in the mine working floor. To analyze the developed mathematical model, it is required to perform calculations on 160 combinations of the reduced rock strength and area of a foot bearings being used, i.e. four variations of the reduced strength; and 40 foot bearings (75 to 750 mm2) for each of them. Results of the field studies, described by the paper, have confirmed dependence between area of a support foot bearing and depth of its forcing in a mine working floor. Mathematical model, developed relying upon the data, makes it possible to forecast a depth of a support foot bearing forcing in a mine working floor during its operation in the context of various combinations of rock mass stress-strain properties and geometry of foot bearings being applied.

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The synthesis of surfactant fatty alkanolamide i.e. coco mono-ethanolamide was observed in this study. The fatty acid methyl ester (FAME) resulted from trans-esterification of coconut oil, treated with mono-ethanolamine to be coco mono-ethanolamide, using ZrCl4 as a catalyst and tert-amyl alcohol as a solvent. The observed reaction variables are the solvent ratio and stirring speed, and their effect on the converted FAME. The results showed that the 4:1 (v/w FAME) solvent ratio, and 300 rpm stirring speed gave the best results. Structural tests performed with FT-IR spectroscopy show that the surfactant obtained includes the fatty alkanolamide group. The results of this study are expected to produce cheap fatty alkanolamide surfactants obtained from renewable raw materials.

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Microstrip antenna is one type of antenna that has been widely used in laboratories in universities because it is practical and easy to produce. The author uses different amount of clover-shaped patch on two different microstrip antennas with 3x3 and 5x5 asymmetrical format to analyze the parameters on 2.4 GHz operation frequency. The results of the simulation of VSWR values were consecutively 1.5 and 1.204. The results of simulation for bandwidth were consecutively 368 MHz and 435 MHz. The results of simulation for gain value were consecutively 8.071 dB, and 8.873 dB.

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Continual water supply is one of the most vital daily requirements of communities for industrial, agricultural, commercial, and household uses, e.g., drinking, cooking, and cleaning. It is common for people to get water by using pumps to draw water from an underground water tank and fill an upper tank. However, use of a non-automated switch to turn a pumping machine on and off may sometimes cause water spills or non-due, increased electricity consumption. This paper presents simple, low-cost water tank monitoring system using an Arduino board. The proposed system is constructed from automatic switch module, ultrasonic sensor, pumping machine, turbidity sensor, and Arduino microcontroller so as to automatically switch the water pump on and off according to the level of water in the storage tank. In this system, the tank monitoring results are displayed on LCD screen that, in addition to the water level, shows the water turbidity to monitor suitability of water for household use. This system controls water pumping, eliminates water wastages and leaks, saves electricity, and helps the water users ensure appropriateness of the water for household uses, especially drinking and cooking.

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Jigs provide a means of manufacturing interchangeable parts since they establish a relation with predetermined tolerances, between the work and the cutting tool. Jigs are used on drilling, reaming, tapping, milling and tapping. The objective of this project is optimizing and analyse of the fixable clamping jig for milling machine. The method is modified clamp mechanism of the previous jig, optimize the design of the fixable clamping jig for milling machine, and analyse the result of fixable clamping jig in term of surface roughness. The result of the experiment will be evaluated base of surface roughness by using Portable Surface Roughness Tester, SJ-401. Then, the result will compare with current vise result and fixable clamping result. From the result that have get, the average of Ra value using current vise as a clamping method is higher than using fixable clamping as a clamping method which are 3.468 when using current vise and 1.657 when using fixable clamping for Delrin as a work piece. While for aluminum as a work piece, the average of Ra value using current vise as a clamping method is lower than using fixable clamping as a clamping method using current vise is 3.069 compared to using flexible clamping is 5.908.

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This paper aimed at analyzing the response of the feasibility of guiding principles of Basic Physics II using Augmented Reality (AR) technology on electrical and geometric optical circuit material. This research is a part of research and development with the development model used that is 4D Development, which are Define, Design, Develop and Dissemination adapted. Response questionnaire practicum responses were given to students of the University of Bengkulu Physical Education Study Program in a small group of 20 people. Analysis of the feasibility test used the Rasch model using the Winsteps program. The analysis includes the respondent's ability, the response item's ability, the level of correspondence of the respondent and the suitability of the response item. From the results of the feasibility test analysis of the practicum guide shows that the practicum guide is feasible to use. This is indicated by data from the variable map data which shows the majority of respondents are in the logit value of the respondent is +2.4 and is above the response item. Overall respondent's ability is higher than the difficulty of the item response. It means that almost all respondents agreed on all aspects of the response items provided.

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Cloud computing is a popular technology where all applications and files are hosted on a cloud. One of the most challenging issues in cloud computing is load balancing which needs to be investigated for its perfect realization. Resource Intensity Aware Load Balancing (RIAL) was proposed for load balancing in cloud computing. Based on the dynamic weight assignment to resources, the RIAL selected the Virtual Machines (VMs) from heavily loaded PMs to migrate out and placed those VMs in lightly loaded destination PMs. An Improved RIAL was proposed to consider both the lightly loaded and heavily loaded PMs for selection of destination PMs. However, some important measures such as power consumption, temperature, and traffic were not considered in IRIAL while the selection of migration VMs and destination PMs. So, Power Consumption Aware- Traffic Aware- IRIAL (PCA-TA-IRIAL) method was proposed which considered power consumption, temperature and traffic measures to select the migration VMs and destination PMs. For an optimal selection of migration VMs and destination PMs, optimization algorithms such as Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Artificial Plant Optimization (APO) are introduced in this paper. Based on the crossover and mutation process, GA optimally selects the migration VMs and the destination PMs. PSO algorithm optimally selects the migration VMs to the destination PMs by updating the position and velocity of each particle in the population based on the cost value. APO algorithm is inspired by a tree’s growing process. Based on the light intensity and photosynthesis, each branch of the tree in APO optimally selects the migration VMs and destination PMs. Thus the optimization algorithms optimally map the migration VMs and the destination PMs effectively for load balancing.

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In this work, the square root of the matrix of variances in stochastic point kinetics is analytically deduced using Cholesky decomposition. The system under study is solved numerically using the implicit Milstein scheme, the variance of the neutron population density and the concentration of precursors can be reduced, and better approximations of the expected values are obtained through the implementation of a new independent Brownian motion. The results obtained comprise different configurations of the reactivity parameters, precursor population, time steps, Brownian motion and initial conditions. The results were compared with those reported in the literature, being consistent with them, which is a manifestation of the efficiency of the proposed method.

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Precision control is essential in most engineering applications, which affecting the outcome of the product. In order to achieve precise motion during the positioning tracking, controller playing vital roles that lead to a better outcome. In this paper, three different control strategies are proposed. The widely-known Proportional-Integral-Derivative (PID) is first designed. Then, the improved PID controller, which is so called Fractional Order (FO-PID) is designed. Followed by the designs of the robust Sliding Mode Control (SMC). The main objective of this paper is to evaluated and compared the performance of these controllers, implemented for positioning or trajectory tracking. The results show that SMC capable to generates most precise trajectory tracking compared with others.

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MODIS global evapotranspiration was used widely in the world as terrestrial evapotranspiration for agriculture. This research aimed to evaluate the performance of MODIS global evapotranspiration product as terrestrial evapotranspiration in West Papua. A total of 32 MODIS global evapotranspiration image recording from 2016 to 2018 were used. Four (4) statistical parameters, i.e., mean error (ME), root mean square error (RMSE), relative bias (RBIAS), and mean bias factor (MBIAS) are used to compare value from MODIS Global evapotranspiration product and value of evapotranspiration calculated by climatological data. The results show that MODIS global evapotranspiration value tends to overestimate and have lower deviation than climate data analysis. Statistical analysis present the ME = 0.43 mm/day, RMSE = 0.57 mm/day, RBIAS = 0.18, and MBIAS = 0.85. Based on statistical performance, MODIS global evapotranspiration can estimate evapotranspiration in Manokwari - West Papua with reasonable accuracy.

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In this paper, we propose using a Hexagonal lens with Massive beamspace MIMO. Which it can significantly reduce the number of the (RF) chains, which leads to reduce the energy of the Radiofrequency. The proposed expected for future wireless communication systems. Therefore, we required channel links without loss of performance in the system. In this research, we discuss the Loss of energy from the beam problem. There is an essential issue in this paper to discuss; which is the angle of departures (AoD) for channel paths cannot precisely map on spatial specimen points. Consequently, it degrades the sum rate and energy efficiency of the system. We present the deploying energy-efficient for phase shifter and zero-forcing (EE-PS-ZF). To get a more efficient performance EE and SE, by use in mm Wave Massive MIMO and support by the Hexagonal lens antennas array. The benefit of PS is that it uses a phase shifter to the transformer. Which it can choose various beams by applying a single, but, in traditional precoder, each can choose only one pole. Simulation results show that proposed algorithms perform better by developing method spectral and energy efficiency as opposed to conventional algorithms. The effects also prove this proposed systematic formulation is better than the traditional method.

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The electrical properties of prepared polystyrene/oil shale composites with different concentration: 0, 5, 10, 20, 30 wt. % of oil shale were studied in this paper, under various measuring conditions including filler content and applied electric field frequency. The dependence of AC-electrical properties of polystyrene/oil shale composites on filler content and frequency were studied using the AC impedance technique. The impedance measurements were performed in the frequency range (100 kHz - 1.5 MHz) at room temperature (30oC). Impedance, dielectric constant and AC-conductivity showed frequency and filler content dependencies. The relaxation time were determined for different filler concentrations .The study includes application of some models to explain the observed results. The universal power law of the AC conductivity behaviour is satisfied for different concentration.

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The aim of the work was to study the experience and effectiveness of applying various methods of gas drainage in the mining of a thick coal-seam 52 in the geological conditions of the Kotinskaya mine, Russia. The range of gas drainage methods used at the mine included: preliminary methane drainage (predrainage) of the working seam, drainage from the goaf by vertical wells drilled from the earth's surface; drainage from the goaf by horizontal wells drilled through the pillar from the roadway; drainage from the goaf using a main gas drainage pipeline, installed behind a brattice and connected to a gas-exhausting fan mounted on the earth's surface. During the work, the gas control equipment data and the longwall face productivity data were analyzed. As a result of the studies, the dynamics of the emitted gas of the longwall face was established, the dependences of gas content of the longwall face output were obtained, and the relative cost of various gas drainage methods was established. The conclusion is that the low efficiency of predrainage of the working seam. The scientific novelty of the work is to establish the influence between zones of geological dislocations and the speed of advance of the longwall face and the volume of emitted gas of the block.

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The impact of pollution on the environment requires activities to forestall adverse effects, by the use of various approaches including approaches to predict the effects of pollutants on the environment, determine measures to mitigate the adverse effects and promote the beneficial activities. This research conducted water quality analysis on river Yingi, in Jos, the capital of Plateau State in Nigeria by the assessment of the stream water quality after the effluent from soap industry is disposed into the water body to determine level of pollution in water. Physical, chemical and bacteriological parameters were analyzed, results show that the value of the Biochemical Oxygen Demand of 325mg/l for the polluted water samples at the point of discharge of effluent into the surface water indicates high organic loading into the water body. The average Total Suspended Solids value of 156.44mg/l was reduced to 75.33mg/l at second sampling point, while Total Dissolved Solids value of 679.2mg/l was reduced to 230.25 mg/l by the self purification of the water body; however, there is still need for further treatment to meet standards for various uses. Sodium Absorption ratio of 15.80 shows that the surface water does not meet requirement for use in irrigation purposes. Waste stabilization ponds were designed to reduce the strength of the effluent to a maximum of 25mg/l of Biochemical Oxygen Demand before disposal into the surface water.

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One of the ways to reduce the cost of casting is to smelt pig iron on a cheap stock, that is, to replace expensive foundry-iron and steel-making iron with steel scrap with its further carbonization. Steel waste is basically much better than foundry-iron and steel-making iron in terms of materials, free from harmful impurities and inclusions. The absence of free carbon in the metal stock makes it possible to obtain any of its content in synthetic iron affecting the structure and properties of cast iron. The process of metal carbonization is the most significant stage in the production of synthetic iron. It largely determines the structure and quality of castings. Therefore, it is very important to study the patterns of dissolution of carbon in the melt. In the course of the study, there were established changes in the parameters of the crystal lattice of quartzite while it was drying using different temperature regimes. These changes further affect the lining resistance during the carburization of the melt. This is due to the fact that the production of synthetic iron from one steel scrap leads to a significant increase in the number of carbonizer (to 40 kg by 1 ton of the alloy), and forces the carbonizing process to proceed at elevated temperatures. For this reason, the sintered lining layer should consist of cristobalite, since it can withstand higher melting temperatures.

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In the article it is offered to use chemical reagents for extraction of residual hard-to-recover oil, existing traditional methods. Such reagents can serve as surface-active substances of nonionic character. The advantage of the latter is their solubilization and lower adsorption value compared to ionogenic analogues.

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In this research work, steel plate girders (SPGs) having the web openings with the elliptical shape are analysed. The finite element ABAQUS software is applied. An experimentally tested SPG is used for the modelling verification. Then, the SPGs are developed. Three-dimensional (3D) finite element models of the SPGs are analysed nonlinearly considering various variables. The variables are adopted in order to deeply examine the performance of the SPGs using the finite element method. These variables include: 1) number of the openings, 2) arrangement of the openings, 3) using steel frame around the openings, 4) utilising diagonal steel stiffeners to connect the steel frame around the openings to the corners of the SPGs, and 5) thicknesses of the steel frame and the diagonal steel stiffeners. The obtained results are compared and discussed considering the effects of the variables. It is concluded that increasing the number of the openings has an adverse impact on the ultimate strength of the SPGs. The arrangement of the openings in the SPGs significantly affects their performance. The horizontal openings are superior to the vertical ones. Utilising the steel frame around the openings and/or the steel stiffeners improves the ultimate strength. Enhancing the thickness of the steel frame and/or stiffeners increases the ultimate strength. The assessment of the failure modes of the SPGs is also done.

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The purpose of this study is to identify and describe the health quality of stone carving workers exposed to noise by production machine. A total of 30 workers consisting of 29 men and 1 woman with an average age of 42.2 years, were selected using the saturation sampling method. The respondent had worked for approximately14.4 years (8 hours/day), with 83.3% possessing elementary-junior high school education, and 56.7% had never worn personal protective equipment while working. Their health quality was measured using the physiological and psychological aspect, which includes blood pressure and hearing quality, as well as workers’ comfort. The observation found an average noise level of 117.93 dB, 110dB, and 111.3dB from saw, grinding, and turning machine, respectively. This level is over from the Threshold Value set in the Minister of Manpower Decree, Republic of Indonesia Number 51/Men/1999 is 85 dB for a maximum work time of 8 hours/day. The average blood pressure (systole and diastole) of the respondents was 126.2 and 85.8, in the condition of prehypertension. The hearing quality of 43.3% of the respondents was in a moderate condition in both left and right ears, with an increased hearing threshold on average between 41-60 dB, which led to permanent deafness or Permanent Threshold Shift (PTS). Furthermore, 36.7% of respondents were quite disturbed by noise from the work environment, 50.1% had communication problems, 53% were often fatigue, and 46.7% had muscle tension for the past 4 years. Psychologically, noise in the work environment caused disturbance towards 36.7% of respondents. Therefore, it is concluded that the health quality of stone carving workers in Muntilan Subdistrict, Indonesia, is quite poor. Suggestions from this research are implementing a health literacy program accompanied by assistance and empowerment. As a result, the stone carving workers have a high awareness of access and apply various health information in their daily lives, especially when working.

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An educational computer program called Armadura2D was developed for matrix analysis of plane trusses, which is intended for engineering students. The program has a great advantage over commercial software, since it is designed to assist step-by-step matrix analysis of plane trusses calculation; this is essential for the lessons of the Structure Analysis course, in the civil engineering undergraduate program. This paper provides a conceptual and mathematical model, a pseudocode of the computational model developed in FORTRAN, the verification of the accuracy of the computer program with a classic problem extracted from a classical book and results are compared with Ansys^® simulation software. In conclusion, this application is an alternative support that enhances the traditional teaching-learning process inside classrooms, and the autonomous learning of civil engineering students of the matrix analysis, particularly for plane trusses.

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