Ice accretion on aircraft components starts when an aircraft flies through atmospheric clouds containing super cooled liquid droplets, which have a temperature below freezing point but are still in a liquid state. Ice accretion occurs when water droplets impinge and freeze on the unprotected frontal regions of aircraft surfaces. The accumulated ice on aircraft components degrades the aircraft performance and causes serious flight problems. In this study, a computational fluid dynamics package is developed using open-source software. The created package is used to predict rime and glaze ice shapes on a wing airfoil for different icing condition cases. The results show a satisfactory agreement in ice shape prediction obtained using the OpenFOAM and Octave software with the corresponding data in the literature.

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Corn stalk was used as an adsorbent to observe removal metal ions (Cd2+), loading time and channeling effect in continuous adsorption column. This study investigated solution in concentration 50 ppm with variation influent flow rates (5, 10, 15 mL/min) and shape/size adsorbent (1/4 round shape, 50 mesh, and 70 mesh). Kinetic adsorption has been observed of influent flow rate 5 mL/min with size 70 mesh. The experiment was used corn stalk adsorbent in the column and down flow direction. The effluent samples were collected in every interval 28 mL. The shortest loading time obtained at 15 mL/min with corn stalk adsorbent shape at 1/4 round. Phenomenon of channeling effect was clearly exist in adsorbent shape at 1/4 round. The results showed that % removal efficiency kinetic obtained 100; 100; 71, 3; 45, 34 (%) with sampling volume 112 mL was reach equilibrium. The highest removal efficiency obtained 43, 55 % at flow rate 5 mL/min with adsorbent size 70 mesh.

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N-acyl lysine is a surface-active substance that can reduce interface tension between oil and water. N-acyl lysine was synthesized by calcium oxide amidification of lauric acid and lysine. The study aims to increase lauric acid conversion by observing the effect of substrate ratio, catalyst amount, and solvent ratio, through the preparation and observation of mathematical models using Box Behnken Design and Response Surface Methodology. Optimal conditions are observed in the ratio of lauric acid to lysine 1:2; 1:3; 1:4, catalyst amount 3%; 5%; 7%, and a solvent ratio to lauric acid 1:1; 1:2; 1:3. In this optimal condition, the conversion of lauric acid will increase by more than 80%. The variable amount of catalyst showed a more significant effect in increasing lauric acid conversion. The results showed that all three variables affect the percent conversion with an R2 of 90.32%.

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The estimation of water influx from a surrounding aquifer into a Coalbed Methane (CBM) reservoir is a key parameter in an appropriate reservoir characterization activity since the degree of connection between natural fractures with other reservoir units has an economic impact. The solution of the traditional diffusivity equation for water influx cases has been somehow extended to CBM reservoirs so several ways of estimation the aquifer leakage factor has been introduced; including type-curve matching which involves trial-and-error processes. In this work, three expressions for the estimation of the aquifer leakage factor of CBM reservoirs are introduced using transient pressure analysis by reading characteristic featured taken from the pressure, pressure derivative and second pressure derivative versus time log-log plot. These equations were successfully tested with synthetic examples obtaining absolute deviation errors, in the worst scenario, lower than 10% which is very good for a parameter with such very small values. However, the best results provided errors lower than 1%.

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This paper presents two novel methodological approaches to calculate the extrinsic parameters of cameras and the inverse kinematics of robots, two aspects commonly addressed in autonomous robotic operation that require performing three-dimensional (3D) reconstruction and object gripping. The functionality of these new approaches is demonstrated, and a comparison with current methodologies is performed. The first methodology detail how to calibrate the extrinsic parameters of a camera from linear regression, while the second explains how to find the inverse kinematics using the Newton-Raphson numerical method, also, a metric is presented to define the error between two homogeneous matrices. With this, we can show that it is possible to obtain a matrix of extrinsic parameters with an error of , and observe that the calculation of the inverse kinematics with the proposed method reduces the error on average by 99.8% concerning the conventional way.

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The removal of nitrate and phosphate ions from wastewater has a major concern nowadays. Excessive intake of nitrates by humans in drinking water and food can induce methemoglobinemia and stomach cancer. Therefore, it is necessary to remove nitrate and phosphate ions from wastewater. Adsorption using nano-adsorbents becomes a promising method for phosphate and nitrate removal from wastewater because of their availability, low cost, stability, large surface area to volume ratio and high adsorption capacity. In this research an industrial waste from El Masryeen Steel factory which is Fume Dust from an Electric Arc Furnace (FD-EAF) is used for simultaneous removal of nitrate and phosphate ions from an aqueous solution. The Maximum nitrate and phosphate ions removal percents 52.74 and 92.38 %, respectively using FD-EAF waste are achieved under these conditions; pH~7, initial nitrate ion concentration = 6 mg/L, initial phosphate ion concentration = 1 mg/L, adsorbent dose = 6.5 g/L and contact time = 90 min. Simultaneous adsorption of nitrate and phosphate ions are well described by pseudo second order kinetic model (R2 = 0.995) with respect to nitrate and (R2 = 0.955) with respect to phosphate as they fit with the experimental results better than the pseudo first order kinetic model (R2= 0.884) with respect to nitrate and (R2=0.868) with respect to phosphate. The rate limiting step is determined using intraparticle diffusion model and Byod plot. Isotherm models are studied for single component and multi-component adsorption systems. For two parameters isotherm model; Langmuir isotherm (R2 = 0.989) fits with the experimental results in case of single phosphate adsorption. In case of single nitrate adsorption from aqueous solutions; Langmuir isotherm (R2 = 0.9957) fits with the experimental results. For three parameters isotherm; Dubinin-Radushkevich isotherm and (R2 = 0.977) and (R2= 0.9849) for single phosphate and single nitrate ion removal from aqueous solutions, respectively fit with the experimental results better than BET isotherm model.

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Urban wetlands play a key role in the ecological structure of cities. Population growth and unsustainable land-use change have led to fragmentation and biodiversity loss in wetlands. The objective of this paper is to show a dynamic modelling study of the influence of land-use change on biodiversity in a wetland of a Latin American megacity (Bogota D.C., Colombia). A multispectral analysis of satellite images was applied to study the change in land use. A dynamic simulation model that considered the relationship between population size, and change in land use, biodiversity, and eutrophication level was also developed. The results suggested as the main indicator variable of the change in land use to population size. During the dynamic simulation, an exponential population growth was observed. Conversely, natural and transition areas of the wetland decreased by 99.6% and 100%, respectively. In this prospective simulation scenario, natural area of the wetland decreased by 5.95 ha/year. Dynamic simulation allowed the development of exponential (R2 = 0.927), exponential (R2 = 0.938), and logarithmic (R2 = 0.998) regression models between the population size, and natural area, biodiversity, and eutrophication level, respectively. This study is relevant for deepening knowledge regarding the use of dynamic models that seek to simulate the conditions of change in land use and biodiversity in urban wetlands.

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Smart Agriculture aims to develop a technology-based agricultural system that addresses climate resiliency, sustainability, and productivity of upland rice. The application of the internet of things to agricultural production effectively convey contemporary farm production to warrant food security. The agile model methodology was used in this study in developing an agricultural system that automates and controls temperature, relative humidity, and soil moisture. Microcontrollers are programmed to gather environmental data remotely utilizing internet technology. Environmental data was used as a stimulus to trigger irrigation and cooling system. Descriptive statistics had been used to assess the functional suitability, performance quality, compatibility, usability, reliability, security, maintainability and portability of the system developed by IT experts and upland rice farmers of Isabela. In general, in descriptive statistics, mean and standard deviations had been used to analyse the data relating to the reliability of the application produced and the assessment of IT experts and farmers. The developed application was found to adhere to ISO 25010 in terms of ISO 25010 compliance.

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The objectives of this study were to improve the surface hardness of specimens and maintenance of JIS G3141 SPCC steel specimens by coating with TH450 Chrome Nickel Amorphous using wire arc spray and to compare the cooling rates of specimens under difference conditions. Mechanical testing was performed using Micro Vickers Hardness Tester for hardness measurement, which revealed that the average surface hardness ranged between 560-600 HV. HAZ of coated areas had different effects on cooling rate on SCCW and SCCNT specimens which showed the hardness between 155–160 HV and also showed slightly changes in microstructure. While SCCO and SCCS specimens were most affected by heat, their hardness decreased and ranged between 80-90 HV. The tensile test of uncoated and coated specimens cooled under different conditions was then conducted and it was found that the ultimate tensile strength of plain specimens was 283.35 MPa which was slightly different. However, %elongation of coated specimen was higher than that of all other specimens. On the other hand, notched and coated specimen showed the ultimate tensile strength of 342.41 MPa and was higher compared to those of all uncoated specimens. However, %elongation showed no difference. According to One-Way ANOVA, P-value in F-test was 0.000 which was statistically significant at a level of 0.01. Tukey’s multiple comparison test results and confidence levels showed the differences which were found that spray coating increased % elongation and tensile strength.

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This study compared the effects of single stage sous vide (55 or 59°C for 12 h), double stage sous vide (55 or 59°C for 6 h, then 70°C for 6 h), and conventional cooking (75°C for 30 min) on the physicochemical, textural properties, microbial, and odor of loin steak from swamp buffalo. Local markets provided a total of 25 buffalo beef samples. They were shipped, chilled, trimmed, cut, weighed, and pH and color checked. They were then vacuumed, cooked, chilled, and evaluated for quality, texture, safety, and odor. The findings showed that meat from TC75 looked lighter and yellower (P<0.05). Cooking with the SV55 treatment reduced cooking loss (CL), transversal shrinkage (TS), Warner-Bratzler shear force (WBSF), toughness, and almost all texture profiles (P<0.05). Multi-step sous vide treated samples had higher CL and longitudinal shrinkage (LS) (P<0.05), except for total color difference (?E*). Meat from TC75 was tougher meat and stronger smell. All cooking procedures were justified as producing meat safe to eat. PCA may be used to determine the quality of beef prepared in various methods. We concluded that the buffalo meat in sous vide cooked at 55°C for 12 h had the potential desirable outcome of upholding moisture level and physical form, producing tender meat, lower carbon footprint, lesser odor of steaks than other treatments.

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A mathematical model of heat exchange of the process of production of granular fertilizers in the fluidized bed was developed. The mathematical models of the fluidization and granulation process in the fluidized bed are analyzed. The main processes affecting the production of granular mineral fertilizers - heat exchange, mass transfer, vaporization, crystallization - are determined. Transient characteristics of air temperature, temperature of granules and moisture content of granules were obtained. The computer experiment confirmed the adequacy of the proposed mathematical model of the process of production of granular mineral fertilizers in the fluidized bed. The main characteristics that affect the production of pellets in a fluidized bed are air temperature and pellet temperature. To obtain a fertilizer of a given quality, it is necessary to control the moisture content of the granules. The proposed mathematical model of heat transfer of the process of production of granular fertilizers in the fluidized bed together with the controller can be used to build an automated process control system.

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The main aim of this study is to develop a high strength cement mortar with a new composite material of cement matrix. This study focuses on the flexural behavior of textile reinforced concrete with hybrid fabrics (Basalt fabric and S Glass fabric) under elevated temperatures at 100°C, 200°C and 300°C. To evaluate the flexural performance, tests were conducted on conventional mortar beam which is a reference mix, one layer of basalt textile reinforced beam specimens, one layer of S-glass textile reinforced beam specimens and two layers of basalt and S-glass textile reinforced beam specimens which are treated at 100°C, 200°C and 300°C. On experimentally comparing the textile fabric reinforced specimens with non-reinforced specimens, the textile fabric with the combination of basalt and S Glass fabric reinforcement have higher flexural strength in all the temperatures compared to reference specimens.

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Most bus companies in developed countries have provided web or mobile application-based services for their customers. Unfortunately, such services cannot be offered in many countries, including Indonesia, due to technology infrastructure limitations or a poor accessibility/usability of the internet. This paper aims to identify potential web or mobile application users for bus passengers in Indonesia based on the city from which they reside and their age. This paper analyses real bus passenger data between Bandung and Cirebon on the Indonesian island of Java. Identifying potential users of web or mobile-based applications for bus passengers based on their city of residence and age can be reliably studied using the simplification of correspondence analysis. One can also utilize many of the features for such a study including confidence regions that can be circular or elliptical in shape. This paper shows that there is great potential for Indonesians to use online or mobile-based applications if bus companies, or the government, provide them with such resources freely.

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The SAT problem is a very important topic in the computer science, its condition of NP problem has been a focus of studies and approaches for resolving it in a low computational cost as well in time as in space, e.g., the International SAT competition that started in 1992 and remain in force until the date. Its importance stems from the fact that resolves decision problems that can be very complex because of its number of restrictions. This paper presents a novel strategy based on clusters of literals that conforms the nodes of a dynamic tree that resolves the SAT problem, the implementation of which includes the clause as the cluster and a heuristic function to select it. In addition, the implementation is compared against recognized solvers that has been winners of competitions of SAT solvers.

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