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Poor water quality is characterized when used for bathing with foamy water, contains solvents and deposits, emits odors, non-neutral acidity, excess microorganisms, changes in water temperature and colored water. The purpose of this water treatment is to remove most of the suspended solids and dissolved materials. Several processes that can be applied in this water treatment include the separation of coagulants and neutralization through contact with palm fiber as a natural fiber, activated carbon, silica, and zeolite materials. In this study, the prototype Water Purifier system (WP system) has been tested in the form of a tube to separate concentrated river water through the designed channel. The parameterized Total Dissolved Solid (TDS) quality, pH and mercury content have good values for the quality of water for spawning with a value of 1.6 ppb. The water purifier arrangement can reduce the maximum mercury (Hg) value by 17.2%, where the value is only 0.6 ppb above the standard that has been used. [ABSTRACT FROM AUTHOR]

This study reveals the construction of a water filter arrangement in a river using finite element modeling with CAE software. The water filter consists of palm fiber as a natural fiber, activated carbon, silica, and zeolite with varying distances between filters in the channel. This water filter is modeled as a porous zone in the simulation process. The finite element method begins with pre-processing, among others designing the water filter construction, meshing, inputting material properties, and applying boundary conditions. The second is solving, which is the calculation done by the computer. Calculations in the simulation are based on the convergence of energy and momentum. The final step is post-processing which displays the results. Based on the simulation results, a larger filter distance results in lower pressure and velocity compared to a smaller distance. The best model is the model with a gap between filters of 500 mm because of the low output speed with small pressure change. The slow speed has encouraged fouling and the low pressure has inhibited the growth of bacteria in the water. [ABSTRACT FROM AUTHOR]

Additive manufacturing has a role in term manufacturing process for creating a part. Additive manufacturing has also popular name that is called 3D printing technology. The 3D printed part is identified as composite material because its strength depends on the orientation layer and the density of material. The surface quality, printing time, and strength of 3D printed part is still observed and developed. So, the purpose of research is to observe the surface quality and strength of 3D printed part to different layer height and orientation of deposit layer in Polylactic Acid material (PLA). The experimental test involved a 3D printer machine to print the specimen regarding to ASTM D3039. Furthermore, the surface roughness of specimen was measured by using SurftestSJ-301 Mitutoyo device. While the tensile was conducted by universal tensile test machine. The layer height of the test specimen was varied from 0.15 mm to 0.25 mm with the increment of 0.5 mm for each specimen. The layer orientation of deposit material was also varied to 0°, 45° to 90°. Base on the observation and analysis, the highest roughness was on the Lh:0.25 mm (12.7 μm) with layer orientation of 45°, whereas the lowest roughness was on the Lh:0.25 mm (0.51 μm) with layer orientation of 90°. The maximum to minimum of material tensile strength were 395.64 kgf, 174.230 kgf and 72.750 kgf for orientation of deposit layer of 90°, 45°, 0° respectively. [ABSTRACT FROM AUTHOR]

– The propeller is one of the main components in an unmanned aerial vehicle (UAV) which is responsible to produce thrust. The objective of this research work was to optimize the thrust force of an existing mini UAV propeller design. The cross-area of propeller edge is an airfoil segment which is ordinarily differing from tip to hub in terms of chord or twist distribution. There are many variables for designing the propeller such as pitch angle, flow angle, chord distribution at the blade span, and twist distribution. Blade elements theory is used for designing the propeller. The blade span was divided into a number of cross-sectional elements and for each section, the cord length and pitch angle were adopted as design variables. A Kriging-genetic algorithm was adopted as the optimization strategy. An existing mini UAV propeller design, DJI Mavic Pro was selected as the initial design. The thrust force was evaluated using the Ansys platform. The optimized propeller design improves thrust force by 35% compared to the initial design. [ABSTRACT FROM AUTHOR]

As a unique structure, aluminum (Al) foam is extensively used in heat transfer, low weight-high stiffness structure, and energy absorption applications to answer the new technological needs in energy saving. This study analyzed the compressive strength of open-cell Al foam fabricated using spherical silica gel (SiO2) particles as a space holder with the variation of particle grain size. The Al scraps were initially melted inside the furnace at 800 °C and subsequently poured into a heated cylindrical steel mold filled with SiO2 having various particle sizes. The vacuum pressure was spontaneously applied just after the melt completely fill the pouring basin. After the remained SiO2 had been removed from the foam specimens, the porosity was measured. The compressive test was conducted on the cylindrical foam specimens using the universal testing machine (UTM) and the macroscopic appearance of outer cellular fracture was captured during the test. The results showed that the larger SiO2 size generates the higher porosity level of 63% at 5 mm particle size. This higher porosity corresponds to the forming of the larger size of pores in the center of specimens. Consequently, at higher porosity, the compressive strength value obtained was lower with only 4.10 MPa, compared to those with the particle size of 3 mm (10.41 MPa) and 4 mm (6.25 MPa), as confirmed by the compression test. The data obtained from the experiment could provide an overview for those who want to develop Al foam with a certain level of strength. [ABSTRACT FROM AUTHOR]

This research aimed to identify the effect of punch speed and tool blanking material on the quality of the sheared edge bone-implant product in the form of a keychain cranioplasty plate implant. This research used Ti-6AL-4V sheet metal, 2.5% clearance between punch-die, various punch speeds, and materials of tool blanking. The tool blanking material used the standardized equipment for the blanking process. The sheared edge characteristic with the swift punch and high elastic modulus improved the shear zone 75% more of the workpiece thickness. The utilization of 71.76 mm/s speed and AISI M2 material created a smoother sheared edge of keychain cranioplasty plate compared to the others. [ABSTRACT FROM AUTHOR]

The pelvic bone fractured surgery commonly includes a plate implant as a part of assembling the fragmented bone fractured. One of the important process of pelvic bone surgery is a plate implant design that is often performed by bending process for getting a shape plate appropriate to the contour of the pelvic bone. This study was purposed to observe the characteristic a Ti plate alloy implant of the bending process by using Finite Element Analysis approach. The stress distribution and deformation of the plate were evaluated to variety distance of dying from the middle axis before and after maximum loading. The punching depth was set as the main load of punch. Hence, the angle of the plate under bending load and spring-back load were recorded and calculated for getting the resultant degree of slope. The existing resultant angle of plate model was caused by stress distribution on the plate. As reported on this study, the reducing distance of die from the middle axis could increase the maximum stress and reduced the spring-back effect so that the plate shape error could be minimized for assembling pelvic bone fractured. The increasing resultant angle of the plate was influenced by punching depth as well as recorded in this study. [ABSTRACT FROM AUTHOR]