Advances in Science and Technology Vol. 112

Abstract: One of the laminated bamboo production processes uses a bamboo planer machine. The use of this technology creates great opportunities for improving the quality of the bamboo processing process. Existing equipment still requires improvements to the power transfer mechanism and system, which affects the frame's shape. Therefore it was necessary to design and retest the frame design so that the machine can produce good shavings. The frame design comprises 50 mm × 50 mm × 5 mm angled steel with ASTM A36 material standardization. The testing method was finite element analysis (FEA) using SolidWorks. The frame was tested using static loading simulation to take mass, maximum stress, deflection, and safety factors. From the simulation, the safety factors value was 6,513. It was too high compared with the predetermined criteria, so the thickness of the frame was changed to 4 mm. The optimization increases material efficiency by 18,227% resulting in reduced frame mass to 76,576 kg. The result of the safety factor becomes 5.930. Keywords: FEA; Frame; Bamboo; Optimization; Strength Analysis; Planer Machine

Abstract: The food industry has taken advantage of additive manufacturing technology to create food from complex ingredients customized as needed. Research on 3d printing of food, especially chocolate, has been carried out, but it needs further development related to nutritional ingredients and the accuracy of printing results. This research was conducted to design an extruder nozzle from a 3D printer used to print chocolate. The extruder nozzle was manufactured using a stainless-steel tube with a diameter of 30 mm with a heater on the outside. The heating control method used a digital thermostat STC-1000, which controls the minimum and maximum operating temperature. The digital thermostat is connected to the heater and fan, which work alternately to get a chocolate temperature distribution that matches the printing specifications. The results showed that the control temperature in the extruder was between 32.2-32.3 °C and could produce an average chocolate printing temperature of 33.4 °C. This configuration produces a stable and continuous extrusion of chocolate on the chocolate 3d printer machine.

Abstract: This paper present a prediction of the centrifugal force caused by the dynamic unbalanced of train wheelset on a developed scale down test bench. The wheelset dynamic unbalanced can be one of reasons for the derailment accidents on trains. Dynamic unbalance represented by the produced centrifugal force can be the main factor causing wear on bearings, noise, vibrations on the train, and the fatal cause of trains accident. The behavior prediction is carried out by applying various eccentricity values by varying the additional weights. The centrifugal force prediction of the developed equipment then compared with the actual size wheelset’s unbalance behavior. The comparison shows a similar pattern between this miniature and the actual size test-bench in terms of the magnitude of the centrifugal force at various eccentricities and rotational speeds. Keywords: train, wheelset, railway, rotating unbalance

Abstract: At this time, it has become commonplace for aircraft to use high lift devices. The high lift devices used include flaps, slats, slots, elevators, ailerons, and others. This study examines the effect of multiple elements on the wing, especially the combination of slat slots and flaps in several configurations.. This research was conducted with numerical simulations on wing airfoil NACA 43018. The observed conditions were rectangular wing (no slats, slots, and flaps) compared to the use of slats, slots, and flaps under steady flight conditions. The angles of attack used are (α) = 0^o, 2^o, 4^o, 6^o, 8^o, 10^o,12^o,15^o, 16^o,17^o,19^o, and 20^o. Numerical simulation using Ansys 19.1 application with turbulent model k-ε realizable. The use of slats, slots, and flaps does not result in a shift in the stall point but tends to increase aerodynamic performance (C_L/C_D)which is very significant. By paying attention to pressure drag, viscous drag and the resulting induced drag, the use of slats, slots, and flaps reduces a large amount of induced drag so that the lift to drag ratio increases.

Abstract: Industrial image processing technology is widely introduced and applied in various fields such as industrial plants, bio-medical industry, agro technology, and also environmental fields. In addition, image acquisition devices are getting more compact and installed onto mobile phones and handy terminals. Which means that we always carry the devices, and can easily take images (still image and moving pictures) of good quality with high resolution, anytime and anywhere. In the research field, 2D code, known as QR code or Data Matrix, has a great potential for industrial applications. As we already know, QR code has been spread and used with various usage likewise ID recognition, URL display on the sticker, and/or the financial transaction's confirmation processing. Not only QR code, but Data Matrix is also frequently used as the printed tag on various material such as metal, wood, or plastic parts. These are used as a product ID or serial number to be recognized by using a mobile terminal. The 2D code technology can be a powerful tool to check and trace the marketing channel of each part of the product. On the other hand, Sustainable Development Goals (SDGs) have been proposed since 2015, researched and introduced to improve our environment and life. This paper describes the proposals of new application technology related to the concept of SDGs. The main contents are based on science and technology, but these have been developed and implemented by the young students of the college. The process and the details are described in the paper.

Abstract: Flooding that often happens during the rainy season in Klitren urban village is caused by reducing open space as water catchment areas [1]. It happens due to several factors, including a large amount of land that has been converted into residential areas and unsustainable existing drainage systems. To evaluate the amount of runoff produced by the area, the writer conducted a simulation using EPA SWMM 5.1 software. The simulation is conducted to compare how much runoff is generated by the area and how much water is collected according to the drainage system's capacity. Modeling alternatives used including the existing condition and other alternatives such as implementing green infrastructure installations. From the results of the analysis conducted in the study location, the runoff decreased from 3,09 m3/s to 2,92 m3/s, and the runoff decreased by 5,5%. Then, it can be used as a reference for implementing green infrastructure in urban areas.

Abstract: Tunnel 6 of the Jakarta-Bandung high-speed railway is the longest mountain tunnel in Indonesia. This study aimed to evaluate the behaviour of rock masses surrounding the tunnel and support system by conducting surface and subsurface engineering geological investigations. The rock masses at the tunnel construction area were classified based on the Rock Quality Designation (RQD), Rock Mass Rating (RMR), Tunnelling Quality Index (Q), and Geological Strength Index (GSI) systems. The surface and subsurface investigation results show that the tunnel construction area consists of Quaternary volcanic rocks overlying Tertiary sedimentary rocks of the Jatiluhur Formation. The sedimentary rocks have characteristics similar to flysch deposits and are classified as poor to good quality rock masses. The regional tectonic setting had likely worsened the rock mass conditions. Down to a 10 m depth, the rock mass quality is controlled by the RQD value, which correlates with the grain size distribution of the rock masses. The rock masses surrounding the tunnel are anticipated to have an anisotropic behaviour and wedge and chimney failure mechanisms. Consequently, a combination of reinforced shotcrete and bolting is recommended for a conservative empirical design of the tunnel support system.

Abstract: This study aimed to propose alternative support systems for a diversion tunnel at the Narogong Weir, West Java, based on the Rock Mass Rating (RMR), Tunnelling Quality Index (Q), and Japanese Rock Mass Classification systems. Surface geological mapping, drill core evaluation, and laboratory testing were conducted to characterize the engineering geological conditions of the tunnel construction site. The results showed that the study area consisted of alternating layers of siltstone and marlstone of the Jatiluhur Formation. Joints and an anticline are the main geological structures observed in the study area. The uniaxial compressive strength (UCS) values of the intact rocks ranged from 4 to 25 MPa. The rock masses were classified into poor to fair classes. The diversion tunnel was divided into two segments of tunnel support systems. Although the support system characteristics are slightly varied, in general, the rock mass classifications recommended rock bolts and shotcrete as the primary tunnel support systems.

Abstract: Many works of literature stated that the development of new infrastructure, including airports, could affect land-use change as well as built-up areas expansion. The conversion of undeveloped land into business, recreational, and residential sites are driven by the need for complementary facilities for airports. In the end, the development of the airport and these changes are hopefully leading to the economic development of surrounding areas. However, several areas are exposed to some hazards, including tsunamis, earthquakes, drought, and floods, which could potentially hinder economic development. When the built-up areas expand uncontrollably, those risks will also increase in the future. Therefore, this paper will seek to predict the changes in built-up areas driven by the development of a newly built airport area. The case study is conducted in the new construction of the airport, namely Yogyakarta International Airport (YIA) in Kalurahan Glagah, Kulon Progo Regency, as it officially began in 2017. After understanding future land use, this paper will try to develop strategies to minimize disaster risks. The prediction will use cellular automata modeling using the MOLUSCE plugin of QGIS. Other driving factors will also be considered in this paper, such as distance to road, distance to existing residential areas, etc. Finally, the prediction map will be overlaid with hazard maps of the Kulon Progo Regency in order to understand the exposed area. This paper hopefully could be an input to the future policies in Kulon Progo.