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This paper presents the results of research on the process of grinding dried corn stalks to use them as polylactide filler. Shredding was carried out on a laboratory shredder with the use of a design variant based on discs with cylindrical holes. By selecting the design variant, the appropriate grinding speed and the material pressure on the shredder discs, the most favourable parameters in terms of the quality of the shredded product and low energy consumption were selected. The research was conducted to reduce the energy demand during the shredding process and to obtain the shredded material suitable for further processing steps.

This paper uses break-even analysis to determine the cost of producing patchouli oil in Kete Nilam Hijo (KNH). KNH is an industry engaged in the refining process of patchouli oil, located in South Aceh Regency, Indonesia. One obstacle faced by the KNH is that the costs of producing patchouli oil are not yet known. So far, KNH has never made economic calculations in producing patchouli oil. KNH only relies on production based on profit so that profits are not maximized and always fluctuates. In addition, the break-even point for the production of patchouli oil is also not known with certainty. To determine the break-even point, total costs and total revenue will be calculated first. This research was conducted in several stages, namely preliminary study, data collection, data processing, analysis of results, and finally concluding the results of the study. The results showed that the total production cost of patchouli oil refining at KNH in one year was 1,120,018,250 rupiah. Meanwhile, KNH had to sell 1,600 kilograms of patchouli oil to break-even.

The demand for applying sustainability in the construction industry increases the necessity of using natural materials in concrete production. Plant-based natural fibers are cost effective renewable materials which considered a potential way to support sustainable development in both urban and rural regions. This paper investigates the potential of using sugarcane bagasse, palm trunk and banana fibers as concrete reinforcement by determining the effect of different volume percentages of these fiber on the mechanical properties of concrete. The percentage of fiber used was 0.5%, 1.0% and 1.5% for sugarcane, 1%, 2%, and 3% for Palm Trunk, and 0.3%, 0.5%, 0.7%, and 1% for banana. Results showed that the optimum value of sugarcane, and banana is 0.5%, 4% respectively. In addition, the addition of 1%, 2%, and 3% of palm trunk fiber improved the mechanical properties of concrete.

The paper deals with the design of composition and verification of the properties of heavy-weight concrete for the production of weights. Heavy weights from fine-grained heavy-weight concrete can be used as a substitute for harmful lead weights (sinkers) for fishing purposes. Lead fishing weights contaminate water, posing a risk to aquatic animals and birds. The production of fishing sinkers from heavy-weight concrete seems to be a possible substitute. A significant reduction in the use of lead fishing sinkers in the European Union is currently under preparation. The formulas of heavy-weight concrete from fine aggregate (fractions max. 2mm) were designed and tested. The consistency of concrete was designed for casting. The optimum vibration frequency of concrete compaction was determined at 75 Hz, resulting in a smooth, colourable surface. The density of the dried concrete after 28 days was 4000 kg.m−3 using a magnetite aggregate with an apparent density of 5.07 Mg/m3.

The paper presents experimental investigations of straw cutting in the form of triticale. The cutting was performed using a specialized testing station adapted for mounting on a MTS Insight 50 kN testing machine. It is allows to change the cutting blade, which made it possible to study the effect of changing the rake angle of its blade and the inclination of the cutting edge on cutting force value. The influence of the linear speed of the knife and the size of the gap between the blade and the counter-blade was also investigated. The results obtained allowed to select the most favorable values of the above-mentioned parameters of the cutting process in terms of obtaining the lowest value of the cutting force, which consequently determines the process energy consumption. Obtained results are not only guidelines for machine design and cutting devices, but these can also be used as input data for multicriteria analysis, which can result in looking for other values of process parameters not taken into account in the presented studies, and key ones in the direction of the next ones.

The quickly weariness of petroleum products because of the taking off industrialization and vehicles of the world. The excursion for elective fills has had the option to be unavoidable, looking energy of diesel for transportation portion. Biodiesel has transformed into a key source as usage powers for CI engines. Biodiesel gotten from vegetable oils are totally promising alternative fills for diesel engine. The delivered of Hibiscus Cannabinus biodiesel is blended in with diesel fuel like (Hibiscus Cannabinus biodiesel H100%H80%H60%H40%,andH20%.The ignition, execution and outflow qualities will be assessed at variable burdens and consistent evaluated speed 1500rpm, modified weight extent 16.5:1,fixed weight 200 bar and result will be contrasted and diesel fuel.

Company can not be separated from the production process in carrying out its business activities. Therefore, the company strives for the production process to be carried out properly, economically, and to prevent obstacles to the company’s operations. In the production process carried out by AA Company, production operations are the responsibility of the Refinery and Fractionation division. Observations were made at the Refinery Plant 1, where the division has an interest in carrying out a production schedule related to the processing of Crude Palm Oil (CPO) into Refined Bleached Deodorized Palm Oil (RBDPO) with Grade Commerce. Based on field observations, one of the problems that occurred was the RBDPO yield target that was not reached. The company set an RBDPO yield target of 94.50%. But in practice, the yield of RBDPO produced is still below the target set. The idea of problemsolving provided is to analyze the root cause of the problem with Cause and Effect Diagrams, analyze the magnitude of potential failures in the process by using Failure Mode Effect Analysis and provide alternative corrective actions using the 5W + 1H method.

The study on the optimization of hydrogenation and rafination process for cocoa butter substitute (CBS) production using palm kernel oil in small and medium scale industry was conducted. The CBS production process included: hydrogenation, cooling, bleaching, filtering, deodorizing, cooling, and packaging. The optimum condition of the hydrogenation process was obtained using hydrogen with 0.2% nickel catalyst, at 195-200°C, under 2-2.5 bar, using 6.12 hz agitation at 1700 rpm, for 12 hours process. The optimum condition of the rafination process was achieved by bleaching using 2 % bentonite at 80-95°C for 45 minutes and cooling it at 60°C, and deodorizing it at 240°C for 4 hours. The final product of CBS had similar quality characteristics as commercial cocoa butter and was well accepted by consumers. It contained no trans-fatty-acid, 0 nickel, low FFA, and a melting point of 37.1°C.

The aggregate used in the flexible pavement in the city of Sabang must be brought from Aceh Besar Regency. This can affect the high operational cost and the insufficient use of local materials. In anticipation of this, the local mountain rocks used are variated with coconut shell ash as a filler and low-density polyethylene (LDPE) plastic use as asphalt substitution. The method used in this study refers to the 2018 specification of Bina Marga (fourth revision of 2010 version). The research results showed that asphalt concrete wearing course (AC-WC), which filler varied with coconut shells (0% and 25% of the weight), meet all predefined parameters. In terms of AC-WC varied with coconut shell and LDPE, the best combination found in this result was 25% of coconut shell ash and 3% of LDPE. AC-WC varied with this best combination has a stability of 1,780.99 kg, the flow of 2.97 mm, VIM of 4.79%, VMA of 16.51%, and VFA of 70.97%.

PT. XYZ Indonesia is a national company engaged in animal feed production. through the Production Planning Inventory Control (PPIC) department has implemented the Material Requirement Planning (MRP) system for inventory control but in the implementation of the company’s MRP system, the PPIC department only considers the quantity of raw materials that can meet demand without regard to the issue of lot size inventory efficiency, so that the cost of raw material inventory is high. The purpose of this research is to compare the cost of procuring raw materials that have been carried out by the company with the cost of procuring raw materials using the silver meal method and Wagner Within algorithm. From the results of research and analysis conducted a comparison between the methods used by the company with the lot size silver meal method and Wagner Within algorithm in order to obtain the total inventory cost of raw materials in 2016, where yellow corn and rice bran raw materials have the same inventory costs between the methods used by the company, the silver meal method and the Wagner Within algorithm method are Rp. 1,080,000 so they do not have cost savings. As for the inventory of lime stone raw materials, it is more optimal to use the silver meal method and Wagner Within algorithm with a total inventory cost of Rp. 606,394 and can save costs by 35.08%.

In order to study the effect of different mechanical juice extraction methods on the quality of fresh-squeezed apple juice, the optimal fresh-squeezed apple juice processing method was selected. The fresh-squeezed apple juice is processed by three kinds of mechanical juice extraction methods: squeezed juice, spiral juicer and broken juice. Five main evaluation indexes of soluble solid content, titratable acid content, value of b*, value of a* and 625nm transmittance of fresh-squeezed apple juice obtained by three mechanical juice extraction methods were determined. Through the analysis and research of the data obtained from the five indicators, the influence of different mechanical juice extraction methods on the quality of fresh-squeezed apple juice was determined, and the mechanical juice extraction method suitable for processing fresh-squeezed apple juice was determined.

At present, the main factor affecting the quality of the silage of the silage machine is the shredding roller. Therefore, a theoretical model based on single-page hyperboloids and a shredding roller with a herringbone arrangement are designed. Then, the theoretical analysis of each key parameter was carried out. The consumption of energy and throwing height of the shredding roller can be targeted, and the orthogonal simulation was performed on each parameter combination. The optimal parameter combination was obtained as the rotational speed of 1426r/min, the rake angle is 53°, the sliding-cutting angle is 8°, and the influence of each factor and level on the consumption of energy and the throwing height is analyzed successively. The verification of experiment that the shredding loss rate was reduced by 5% compared with the pre-optimization, the optimized of broken stems is 25% higher than pre-optimization, the throwing height was 30mm higher than the pre-optimization, and the consumption of energy was reduced by 3.1% compared with the pre-optimization. The optimized of objective was within the prescribed range.

The increasing demand for Crude Palm Oil (CPO) makes palm oil production companies continue to improve production planning continuously in order to meet customer demand. Companies that are engaged in CPO production in the Medan city experience problems are not optimal due to companies are often faced with a situation in the form of a production mismatch with the volume of demand due to demand fluctuation. Therefore it is necessary to optimize the procurement of CPO by using linear programming methods. This method is used to maximize or minimize the resources owned by the company with several decision variables, objective functions and constraint functions. The results shows that the decision variables used are CPO cost, the cost of procurement using their own FFB, purchasing FFB cost and processing costs. The objective function is the maximization of company resources and constraint functions consisting of the maximum capacity of the factory, the availability of purchase FFB, the purchase quota of FFB, the availability of direct labor, processing transfers and processing costs.

The use of local bamboo biomass bricket is very effective and eficient to be used as an alternative fuel. This reasearch aimed to (1) evaluate the proximation and calor value of three types of local bamboo based on the variasi jenis bambu, (2) to determine therma efficiency of the bamboo charcoal bricket. This research applied experimental method by using three types of material through efficiency evaluation on the bricket stove. The result of experiment on the comparison of calor value was found that bricket type B1 (Petung Bamboo) has the highest calor value as 5176,333 cal/gram, B2 (Wulung Bamboo) has the value calor as 4873 cal/gram, and B3 (Apus Bamboo) has value of the calor as 5025 cal/gram. Meamwhile, the result of burning experiment on the stove showed that B1 (Petung Bamboo) is the best in terms of the ability to boil water for five (5) times by thermal efficiency l in the amount of 56,91%.

The article describes an innovative approach of the grinding heterogeneous frozen meat raw materials on the basis of single-stage milling method. In the technological cycle, in comparison with the traditional solution, the one shredder is used instead of three meat-cutting machines. The high quality of the finished product is achieved by modeling the grinding parameters. As a result of the analysis of the experimental data of the “new” technological process of meat grinding, an intelligent control system for the production of minced meat with machine quality control is proposed. Promising technology will reduce the cost of production of mass demand products that meet quality standards.

The granulometric composition of Pumpkin seeds of the “Samson” variety used as feedstock for food and vegetable oils producing industry are studied. Their geometric dimensions and physical indices are obtained experimentally. Results and dependencies necessary for designing and dimensioning of drying ovens from installation for vegetable oils production are obtained.

Nata de coco is a bacterial cellulose produced by Acetobacter xylinum in the process of fermenting coconut water. It is renowned for its high fiber content. The chewiness of nata de coco is proportional to the fiber content. There are many brands of nata de coco available in the market. Six different brands are included in this study. The mechanical strengths have been evaluated using a Universal Testing Machine. Based on the tensile test results, the lowest Young’s modulus is 3 MPa, attributed to the brand labeled as F as the most elastic nata de coco among the six brands. The degree of elasticity of nata de coco also corresponds to the sugar content. Further, the optical properties have been observed using a UV/Vis Spectrometer. Clearer nata de coco yields higher transmittance value. Meanwhile, the turbidity commensurate the nitrogen content.

Jasmine essential oil has been studied and widely used for many centuries in many countries throughout the world. However, relatively little is explored about jasmine essential oil application. Here, we produced essential oil of jasmine by hydrodistillation method. The effect of distillation time, distillation temperature, feed size, water-raw material ratio to the yield of the distillation process was analyzed and recorded. With 6 hours, 120°C, grind fresh and ratio of 2:1 the yield was 0.092%. Antibacterial compounds of Jasmine essential oil were determined by measuring Gas Chromatography-Mass Spectrometry equipment. Jasmine essential oils are applied to develop the facial cleanser product that is safe for human. Jasmine facial cleanser will be a new product in Viet Nam’s cosmetic with many potentials.

The high level of consumption of processed beef products is a promised business opportunity to be developed. The shift in people’s consumption patterns in consuming processed meat products from fresh meat into ready to eat processed products has encouraged some parties to develop technology in terms of processing beef. The way of making shredded meat is still conventional, using bare-hands, knives or forks to slice meat after cooked into a shredded part. Obviously, the process of making shredded meat is taking times, more power, and by pounding using forks is considered to be less safe for workers. The purpose of this study was to obtain a simpler beef machine for raw materials to make shredded meat using 1.5 horsepowers (hp) drive motor. Modified the design of construction by designing the casing cylinder, the hopper inlet and outlet, the tub and the table, developing a new machine that is able to be tested. 1 kg of beef so that the results of the measurement of the sound texture of the fiber consisted of 0.5 mm fiber thickness, 30mm length; 1mm fiber thickness, 35mm long and 1.5mm fiber thickness, 35mm long. The capacity of the results of beef steaming is 3.3 ounces/minute or 1kg per 3 minutes. Therefore, it can be concluded that the more the gap in the casing, the better the smoother the results could be.

Turmeric oil has many uses in the field of medicine and food. There are many methods of extracting essential oils from plants. However, every traditional method has limitation regarding the heat transfer, time or quality of the oil obtained. In this study, the combination of microwave extraction and response surface methodology are used to extract turmeric oil and optimize the factors that influence the extraction process. The results showed that optimal influencing factors such as the ratio of water to the raw materials were 2.99:1 (mL/g), the microwave power used at 456.60 (W) for the extraction time was 102.43 (min) for the essential oil yield of 0.95 (%) with 100 % reliability.

Orange oil with many applications in food and beautify people. In this sense, traditional methods of extracting essential oils have been less effective and gradually replaced by more optimal methods. The combination of microwave assisted hydro-distillation and treated with response surface methodology are considered as a new and modern method for extracting oranges and optimizing the factors that influence the extraction process. The results showed that influencing factors such as the ratio of water to the raw materials were 3.2: 1 (mL/g), the microwave power used at 465 (W) for the extraction time was 96.63 (min) for the essential oil yield of 4.0 (%) with 99.5 % reliability.

The paper presents the change of functional parameters defined on the Abbott-Firestone curve in order to evaluate the surface quality of the balls from the four ball tester, after tests done with several vegetable oils. The tests were done using two grades of rapeseed oil (degummed and refined) and two grades of soybean oil (coarse and degummed) and a common transmission oil (T90). Test parameters were 200 N and 0.576 m/s (1500 rpm) for 60 minutes. For the refined rapeseed oil, the changes in shape of the Abbott-Firestone curves are more dramatic, these being characterized by high values of Spk (the average value for the wear scars on the three balls), thus being 40% of the sum Svk + Sk + Spk, percentage also obtained for the soybean oil, but the value Spk being lower. For the degummed soybean oil, the profile height of the wear scars are taller than those obtained after testing the coarse soybean oil, meaning that the degumming process has a negative influence on the worn surface quality and the lubricating capacity of this oil. Comparing the surface quality of the wear scars on fixed tested balls is a reliable method to point out the lubricant properties of the vegetable oils, especially if they are compared to a "classical" lubricant as a non-additivated transmission mineral oil T90. The best surface after testing was obtained for the soybean oil, followed by T90 oil and the degummed grades of the soybean oil and rapeseed oil (these three giving very close values for the functional parameters), but the refined rapeseed oil generated the poorest quality of the wear scars on the balls, under the same testing conditions.

Energy demand increases every day, while the energy source especially fossil energy depletes increasingly. One of the solutions to overcome the energy depletion is to provide renewable energies such as biogas. Biogas can be generated by corn cob and food waste. In this study, biogas production was carried out by solid-state anaerobic digestion. The steps of biogas production were the preparation of feedstock, the solid-state anaerobic digestion, and the measurement of biogas volume. This study was conducted on TS content of 20%, 22%, and 24%. The aim of this research was to compare kinetic models of biogas production from corn cob and food waste as a co-digestion using the linear, exponential equation, and first-kinetic models. The result showed that the exponential equation had a better correlation than the linear equation on the ascending graph of biogas production. On the contrary, the linear equation had a better correlation than the exponential equation on the descending graph of biogas production. The correlation values on the first-kinetic model had the smallest value compared to the linear and exponential models.

This research focuses on the problem occurred in the reactive dye synthesis process of a global manufacturer in Thailand which producing various chemicals for reactive dye products to supply global industries such as chemicals, textiles and garments. The product named "Reactive Blue Base" is selected in this study because it has highest demand and the current chemical yield shows a high variation, i.e. yield variation of 90.4% – 99.1% (S.D. = 2.405 and Cpk = -0.08) and average yield is 94.5% (lower than the 95% standard set by the company). The Six Sigma concept is applied aiming at increasing yield and reducing variation of this process. This approach is suitable since it provides a systematic guideline with five improvement phases (DMAIC) to effectively tackle the problem and find the appropriate parameter settings of the process. Under the new parameter settings, the process yield variation is reduced to range between 96.5% – 98.5% (S.D. = 0.525 and Cpk = 1.83) and the average yield is increased to 97.5% (higher than the 95% standard set by the company).

The process of cooking oil production generally is started by grating the ripe coconut meat, then pressing the grated meat to obtain coconut milk, and finally heating the coconut milk to obtain the cooking oil. Pressing mechanism to obtain coconut milk is a very important step and decisive in the process of producing cooking oil. The amount of milk produced depends on the pressure applied at the time of pressing grated coconut. The higher the pressure, the more milk is obtained. Some commercial mechanical pressing tools that available in the market are not efficient due to the working steps too much and take long time per cycle of work. The aims of this study was to design and manufacture a power screw squeezer for the collection of coconut milk. Power screw produces a compressive force in the cylinder to push and press the grated coconut until the end of the cylinder while the coconut milk and coconut dregs flow out simultaneously. Screw press was designed using straight shaft configuration with square profile. Performance test was done to investigate the actual capacity and yield of milk produced. The results showed that squeezer of grated coconut worked well with capacity an average of 13,63 kg/h and coconut milk yield of 58%.

It has been well established that non-torque main shaft loads influence the internal drive train loads. This paper proposes a scheme that compensates for non-torque loads in the blade pitch controller. The compensation scheme is implemented on a dynamic model developed in FAST/Simulink. Three wind conditions of 8, 11.4 and 20 m/s are examined. The dynamic analysis of the bending moment in the low-speed shaft showed a reduction in bending moment by 3 % for the rated wind speed (11.4 m/s) and 1.8 % for the above-rated wind speed (20 m/s), highlighting the effectiveness of the proposed scheme. However, a reduction in bending moment also slightly decreased the shaft’s speed by 2.3 % and 0.5 %, respectively. Similarly, the turbine power was decreased by 9 % and 1 %, respectively. In comparison, further gain scheduling within the compensation scheme reduces the power loss to as low as 0.3 %. The 2 to 3 % reduction in the low-speed shaft bending moment can significantly influence the drive train loads and easily outweigh any loss resulting in the shaft rotational speed and turbine power. Thus, this paper shows that using bending moment error as feedback within the compensation scheme positively affects the low-speed shaft’s bending moment with the eventual potential of reducing drivetrain loads.

A simulation-based study under partial shading condition is presented for a photovoltaic (PV) module in this paper. In a solar photovoltaic module, some of its cells may fall into the shadow. With multiple peaks, the PV characteristic gets more complex under partial shading conditions. The purpose of this paper is to demonstrate the effects which can cause partial shading in a PV module. Where is done through Simulation by MATLAB / Simscape. Under partial shading and uniform irradiation, the characteristics of the PV module are compared. All results are displayed in graphical forms to demonstrate the outcomes.

In the present scenario the period of rivalry and financial disturbance, a wide range of organizations are using the various optimization techniques or strategies that are helpful for keeping up and enhance the quality and efficiency. In this paper the outline on, the improvement of various boundaries in milling and drilling operation is discussed through some research survey. The ANOVA technique was used to found the significance control factors which help to measure the required surface roughness parameter. The response surface methodology and DOE methods are generally utilized in the various research study on milling and drilling operation. The quality of machining process are depends on various machining parameters like cutting speed, feed rate, tool diameter and structure, cutting depth, work piece material etc. The all above parameters are the key factors for machining optimization process and discussed through this review paper surface roughness has been analyzed Taguchi strategy.

Fractional calculus relates with derivatives, integrals, and differential equations of order not integers. The Bernoulli Differential Equation is a form of the first-order ordinary differential equation. This paper aims to solve the Bernoulli Differential Equation with α fractional-order using the Adomian Decomposition Method, where 0 < α ≤ 1. The fractional derivative used in this paper is the fractional derivative of Caputo. Based on several numerical examples presented in this paper, the results show that the Adomian Decomposition Method is easy and very effective to use for solving Bernoulli Differential Equations with fractional order α.

The paper solves the problem of selecting optimal methods and combining them when performing a complex calculation of all sections of the Laval nozzle. The problem is significant, since different flow modes are realized in different areas of the nozzle and it is impossible to use a single method for the full calculation. Solving the direct problem, parameters in the flow of gas are determined. Solving the reverse problem determine the profile of the Laval nozzle. Profiling is an important applied task for calculating the nozzles of rocket and aircraft engines, or designing experimental turbines. In this paper, we consider a two-dimensional plane axisymmetric flow of an inviscid perfect gas (on the example of dry air). The problem is solved starting with an accelerating subsonic flow via using methods of establishing and finite elements. For subsonic flow found an exact solution (Prandtl-Mayer flow). Solving the problem in a supersonic flow via using proximate methods (the method of characteristics and interpolation for the grid normalization). The solution is supplemented by a method that allows taking into account the features of axisymmetric flow in the nozzle to expand the applicability of the solution for real nozzles. The results obtained – the gas velocity field and the coordinates of nodes. Results allows estimation of the optimal size of the Laval nozzle for the given conditions, its shape, and obtain a flow profile depending on its initial characteristics defined in the previous section of the nozzle. The results of flow simulation can be applied to calculate the flow in circular sections, which are the most common in the current application. The results are confirmed by the solution using the finite element method, and the convergence of the solution in the diffuser is described in the current work. Theoretically, the solution can be applied to a mixture of gases, if peculiarities of physical and chemical transformations and the participation of combustion products are taken into consideration. In this case instead of parameters in the pre-chamber, the parameters of the combustion chamber and the products in it should be used as initial conditions. This calculation will be carried out in future studies of the authors.

It is well-known in the literature that fatigue failures originate from the weakest element within the component loaded volume. In particular, for metallic materials the fatigue crack typically nucleates from the most critical surface defect in the High-Cycle-Fatigue (HCF) region; whereas, it generally nucleates from the most critical internal defect in the Very-High-Cycle-Fatigue (VHCF) region, at stress amplitudes below the so-called ‘transition stress amplitude’. Therefore, regardless of the fatigue region, the P-S-N curves must necessarily take into account the random distribution of the critical defect size. However, in the literature, there are few statistical models that can model the dependency between the fatigue life and the defect size or that can take into account the presence of different failure mechanisms (e.g., surface crack nucleation in HCF and internal crack nucleation in VHCF). In the present paper, a new software for the estimation of the P-S-N curves is proposed. The statistical P-S-N models recently proposed by the authors and implemented in the software are described in the paper. The procedure for the parameter estimation is also explained in detail and the software is finally validated with experimental datasets collected by the authors or available in the literature.

This paper describes a surprising problem encountered in the numerical solution of the Adjoint Euler equations. The basic result presented here is that certain two and three dimensional numerical solutions to the adjoint Euler equations have a value at and near the surface of wings and airfoils that depends strongly on the mesh density and which does not converge as the mesh is refined. The purpose of this paper is to characterize this problem and offer insights as to the possible explanation of this unusual behavior.

Many automotive companies are adding new devices and features to the latest generation of cars. Some changes such as the addition of an adds-on device and car design lead to changes in the aerodynamic characteristics of the vehicle. this study will be carried out on the changes in the aerodynamic properties of the 3 generations of Model cars: Model 1, Model 2 and Model 3 in 2 D Steady state simulation. The car simulated in various numbers of velocities in 40 km/h, 60 km/h, 80 km/h and 100 km/h. The characteristics of aerodynamic force around the car are discussed in this paper from the qualitative and quantitative data. The quantitative which used as measurable data are Coefficient of drag (CD). Quantitative data has better visual explanation of the stream characteristic. The qualitative data which used in this paper are path line and velocity contours. The validation process is conducted with the previous research and the average error was 5%. The results showed that Model 2 has the most aerodynamic design than the other type due to the drag coefficient was lower than the other type.

The agricultural industry is one of the most important sectors for a country because its supports food production. One of the agricultural industries that can increase food productivity is the fertilizer industry. Fertilizers have many varieties. The variant of a fertilizer can be identified by its color. There are 3 types of fertilizers such as NPK fertilizer, Calcium fertilizer and Potassium fertilizer. These fertilizers have different colors. NPK fertilizer has blue color, Calcium fertilizer has yellow color and Potassium fertilizer has red color. Red, Green, Blue (RGB) color spaces and Hue, Saturation, Value (HSV) color spaces are used as extraction of color features on fertilizers which used as fertilizer color features. The color characteristic of the fertilizer is used to classify fertilizer. This paper aims to classify fertilizer based on its color. Fertilizers that have been successfully classified are displayed on the monitor screen. There are 75 fertilizer samples which consists of 3 types of fertilizers and 25 samples for each type of fertilizer used in this paper. Test results show that fertilizer can successfully identified 3 types of fertilizer based on its color. The value accuracy is obtained 100% in the RGB color with the range of RGB color are (40,60,70) to (120,160,170) for NPK fertilizer, (140,120,20) to (210,210,100) for Calcium fertilizer and (20,50,0) to (150,180.20) for Potassium fertilizer.

The aim of the paper is analyze of a new linkages used in Light_Sport_Aircraft control, flaps control, on bases of the aerodynamics, structural modelling of linkages with Multibody System method (MBS) and resistance calculus of wing. In virtual prototyping of the aircraft, these linkages have to be modelled by a minimum number of bodies (MBS min). In this paper is described one concrete mechanical flaps control. This will be the bases for virtual modelling and prototyping of these subsystems as parts of the whole product (airplane).

In the paper the authors used results of static load tests of piles that have been conducted in a full range of loads in order to verify the analytically calculated parameters obtained for a continuous load-settlement curve. For a description of continuous static load test curve of a pile the authors have used Meyer-Kowalow method (M-K method). The result of a static load test is a load-settlement set {N i, si } which is the background for further calculations of M-K curve parameters. Calculations that are presented in the paper were carried out using an original computer program and the authors compared M-K curve parameters, specifically limit the bearing capacity of a pile calculated and measured values obtained from the static load test performed in a full range of load. The research was done in order to determine the optimal method of calculating bearing capacity of pile based on static load test which later can be practically used in the M-K method to obtain full range continuous Q-s curve. Results obtained during the analysis performed by the authors show that the values of the limit bearing capacity of a pile can be calculated with sufficient for practical use accuracy from different parts of the data set, as an example using just the chosen part of the set. The research conducted by the authors points the fact that the limit bearing capacity which is the most important parameter determining safety, can be effectively obtained for different M-K curves using least squares method, even in cases when static load tests were not performed in a full load range. After determining M-K curve parameters it can later be used for further analysis of the pile-soil interactions.

This paper focuses on the numerical method for the geometrically nonlinear buckling analysis of truss with initial member length imperfection. The solution of nonlinear buckling problem of truss with imperfection using a displacement-based finite element is dependent on the imperfection implemented. Generally, the operation of incorporating the initial imperfection to the master stiffness equation develops by master-slave elimination method, penalty augmentation method or Lagrange multiplier adjunction methods. Obviously, the initial imperfection considerably increases the difficulty in finite element formulation nonlinear buckling problem. This research proposes a novel approach to formulate the nonlinear buckling problem of truss with imperfection using mixed finite element method. The mixed balanced equation of truss is formulated using the principle of stationary potential energy. The paper presents novel mixed finite truss element, including initial member length imperfection, considering large displacement. Using the arc length technique, the research develops a new incremental-iterative algorithm for solving the nonlinear buckling problem of truss with initial imperfection in different cases of model formulation, including displacement-based finite element and mixed finite element formulation. The numerical test is presented to investigate the equilibrium path for plan truss with initial member length imperfection. The calculation results in solving problem formulated in both displacement and mixed finite model are converged showing the efficiency and reliability of the proposed method.

The static load test is the most reliable method of indicating the actual pile bearing capacity. Within the pile load increments, the settlement is measured and set of points Q-s (load – settlement) is plotted. The ways of executing the pile load test and their interpretation are far from optimal and have many different approaches. Usually, the pile test does not allow evaluating the bearing capacities within the measured range and extrapolation of the results within the Q-S curves is necessary. None of the present interpretation models includes the influence of imperfections in the pile load test. The paper presents the results of calculations with the model that takes into account the occurrence of imperfections during the test execution. The analysis is based on the modified Meyer-Kowalow curve model, proposed by Meyer and Wasiluk, and on the field test obtained on many construction sites for piles in different technologies, few of them loaded up to the failure. The model considered in the paper allows extracting statistical imperfections in the collected set of points. Imperfections should be understood as mechanical changes of the pile and pile-soil interaction. All phenomena are gathered within one imperfection. The imperfections are due to changing soil and pile skin when the soil body bends according to the Kirchhoff’s principle. Calculations indicate the influence of imperfections on the pile limit load and other parameters of the Q-s curves according to the basic model that exists. Performed analysis based on approximately 65 piles defines three main groups, first with a relatively small influence of imperfections, second with changes of the limit load for the entire pile and the pile toe without the large change of pile character (ratio of skin friction and pile toe resistance) and the third with a significant change in limit loads and pile bearing capacity components ratio (skin and toe). Values measured during the pile load test can be corrected within extract imperfections. Presented model in many cases determines more critical values for designers than basic models suggest.

Since Newton time, Differential Equations have been used to comprehend most of physical, geometrical, and vital science in addition to their participation in the study of arithmetic analysis. Furthermore, they have been used in economical and social aspects. They have been developed and got significant position in various sciences. This paper presents for the non-homogeneous ordinary differential equations with the second order. This idea starts in chapter one which talks about the notion of those equations, their orders, in addition to the study of the linear differential equation with the first order and its solution. Whereas the second chapter studies the ordinary differential equations (homogeneous and non-homogeneous) and their solution. Each chapter is supported by solved examples that cover most of the aspects of the topic and we hope that this paper will make a good reference for those who would like to study this topic furtherly.

In this paper the fundamental concept of repeated linear interpolation and its possible applications in computer-aided geometric design, and start considering basic constructive methods for curves and surfaces. We discuss here a repeated linear interpolation method that we commonly find in computer graphics and geometric modelling. Repeated linear Interpolation means to calculate a polynomial by using several points. For a given sequence of points, this means to estimate a curve that passes through every single point. The purpose of this paper is to construct a polynomial of degree less than or equal to n, by using repeated linear Interpolation.

The paper proposes a model of an equal-wear shape of the working surface of grinding wheels operating in the self-sharpening mode, where the principles of system workability are used. It is established that to obtain engineering solutions, the wheel should be considered as a ceramic body that cuts into the ‘Voicht medium’. A disadvantage of the adopted model is that it does not consider the lag caused by strain. In addition, when grinding, the process temperature and the deformation rate are significantly higher than when the machine parts rub together. It is shown that the condition of equal wear of the wheel surface is provided by equal wear of the abrasive grains on the entire working surface, the density of the working grains on the elementary section of the contact surface. The paper presents conditions under which equal-wear shapes of wheels working with a longitudinal feed are provided.

Previous research has dealt with the topic of topological graph in several aspects and has studied the set of vertices or set of edges as a sub basis for topological space. The topic of domination has received the attention of many researchers in the recent period, because has many applications in the field of computers and networks. The main purpose of this paper is join between topological space and minimal dominating sets of a graph G, By using all minimal dominating sets (MDS) as open set of topology on V (G) . this paper discussed T 2 – MDS (hausdorff property) of path Pn with n ≥ 4.

The paper is devoted to the construction of a fuzzy regression model, the input and output data of which are Z-numbers. The coefficients of the regression model are crisp numbers. The definition of Z-number was proposed by prof. Lotfi Zadeh in 2011 for fuzzy information processing, the reliability of which is also fuzzy measured. In the paper the both components of Z-numbers are values of linguistic variables with the properties of completeness and orthogonality. Operations on Z-numbers are based not on classical fuzzy arithmetic, but on weighted fuzzy arithmetic, which greatly simplifies the operation, but at the same time, the original information features are preserved. The incoming information is formalized using weighted segments, based on which the distance between the initial and model data is determined. The optimization problem is solved with the condition of a minimum sum of squares of these distances, which allows to obtain unknown coefficients of the regression model.

In the present paper, we investigate the numerical methods for solving initial value problems for systems of nonlinear ordinary differential equations with several limiting singular points. Similar tasks have great practical importance in such areas as hydrodynamics, chemical kinetics, combustion theory, computational geometry, and nuclear reactors. However, the exact solution may be constructed to nonlinear initial value problems only in exceptional cases. Numerical methods also do not give the desired result. Explicit methods make it possible to obtain a solution only if there is one limiting singular point on the right boundary of the considered interval of the argument change. Implicit methods also have usage restrictions. They consist of the difficulty or impossibility of overcoming the internal limiting singular points. For solving the considered class of problems, the paper proposes to use the method of solution continuation, which allows passing any limiting singular points effectively. Features of the application of various numerical methods are shown by solving one test initial value problem. The reliability of the obtained numerical results is confirmed by comparison with the finding analytical solution of the considered test problem.

The paper studies the geometry of the Riemann curvature tensor of generalized Kenmotsu manifolds. In this paper, several identities satisfied by the curvature tensor of generalized Kenmotsu manifolds are obtained. Two identities are distinguished from the obtained identities, called the first and second additional identities of curvature of the GK-manifold. Based on additional identities, two subclasses of GK-manifolds are distinguished, and a local characterization of the distinguished classes is also obtained. It is proved that the distinguished two subclasses of GK-manifolds coincide and have dimension 5. In addition, it is proved that the class of distinguished manifolds coincides with the class of almost contact metric manifolds obtained from a cosymplectic manifold by a canonical concircular transformation of a cosymplectic structure of dimension 5.

This paper illustrates a novel approach to determine the probabilistic rutting in asphalt mixtures based on Weibull distribution statistical approach. In this paper, thirty wearing course asphalt mixtures prepared using different binder grades and aggregate sources, are analysed. Cooper Wheel tracker Test (CWTT)and Asphalt pavement analyser (APA) have been used to ascertain the rutting potential of asphalt mixtures with varying binder grade and aggregate source. Mixtures are then ranked based on their rutting susceptibility. The obtained data is processed using two parametric Weibull approach. Scale and shape parameters are figured out by multiple regression technique. Test results are analysed using goodness of fit test. Results indicate that rut depth predicted from two parameter Weibull distribution technique corelates well with the actual rut depth with R2 value of 0.88 for both cooper wheel tracker and asphalt pavement analyser test. It has been found that Weibull distribution bests fit the NHA-A, NHA-B and SP-B graded mixtures with NRL 60/70 at 50°C. A good correlation has been observed between Cooper Wheel tracker and Asphalt pavement analyser as translated by R2 of 0.86. This research is important in a sense that several agencies have adopted rutting as a failure criteria for flexible pavements. By mathematically modelling the rutting response, predicting the rutting behaviour of mastics becomes simpler and more efficient in approach.

The glued timber structure is well-known worldwide engineering product nowadays. Extensive knowledge of wood structure behavior has been as important basic to create new design projects. This paper presents the issue of determining moisture content (MC) in load-bearing glued wood structures, depending on a value of indoor relative humidity and temperature. There are two ways to study timber moisture content – calculation (manual or in programs) and measurement methods. this ways complement each other. Each of methods is more or less suitable for monitoring of structural elements or not suitable at all. Graphs, tables or 3D models of timber moisture content distribution in structure are can received using these methods. Two simple equations to determine timber moisture content are given in the paper. Besides, effect of timber moisture content on durability properties of wood structure is describes there.

Quality is one of the key aspects in every production activity. This research aims to improve the quality of the product on tubing machines used Six Sigma method with DMAI phases. At phase of define, the problem is found attubing machines with defects glue, printing, improper size and paper extension. In the measure phase, DPMO value is 3691 and sigma value is 4, 18. In the analyzephase, the most dominant problem type of defects are glue and printing, will be analyzed according to machine, material and method factors. In the improve phase, the cause of problem will be sorted from the highest to the lowest uses FMEA method. Causes of glue problems are paper rolls are from many suppliers, the extruder needs time to be stable, the age of machine is old, piece of paper tucked in the knife bearing and not optimal material handling. The priority order of printing problems is not optimal material handling, piece of paper tucked in the knife bearing, the paper stuck in the printing unit, and ink are from several suppliers. Proposed improvements with 5W1H can be given according the order of root problems from the largest to the smallest.