bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of earth’s gravitational acceleration and moment of inertia of rigid body using physical pendulum experiments
Authors: Yuningsih N , Sardjito S , Dewi Y C 
Published: May 2020

Abstract
To determine the value of earth’s gravitational acceleration, physical pendulum experiment is preferred over simple pendulum experiment that was previously more popular. In physical pendulum experiment, the object is a rigid body. The swing period and swing shaft position are measured. From these two variables and using the applicable laws of motion, equations can be determined that involve constants which imply the value of the earth’s gravitational acceleration and the moment of inertia of objects pivoting at the center of mass. The independent variable in the equation is a function of the distance of the pendulum shaft to the center of mass based on the parallel-axis theorem, while the dependent variable is a swing period. Difficulty in solving equations is found because of the terms of the equation involving variables in different ranks. In order for the equation to be linear, a dependent variable and an independent variable are combined into new variables. After that, with the linear regression method, the constants of the equation can be determined which can then be determined the value of the earth’s gravitational acceleration and the moment of inertia of the object. The results obtained are quite satisfactory with a relatively smaller error value of 5%. Thus this physical pendulum experiment can be used to determine the earth’s gravitational acceleration and the moment of inertia of an object simultaneously.
Physicochemical characteristic of hydrogen-rich water potato flour
Authors: Budiarti G I , Sulistiawati E 
Published: May 2020

Abstract
Potato may be used as a substitute to wheat which cannot be grown in the tropics. However, potato flour has characteristic physicochemical limitation compared with wheat flour. Potato limitation can be reduced by modification starch. Hydrogen rich water is water that contains antioxidants. It has only been used in the health sector as an anticancer and anti-inflammatory. The antioxidant content in hydrogen rich water can be used for modification of potato starch which is safer than using chemicals. This study examined whether hydrogen-rich water can improve the physicochemical characteristic of potato flour as a substitute for wheat flour. We used a variation of soaking time in hydrogen-rich water (1,2,3,4 hours) and drying method (oven and UV). We found, physicochemical characteristic (water content, swelling power, and reducing sugars) better than wheat if soaked for 3 hours with UV drying method. So, modified potato flour using hydrogen-rich water can be considered as a substitute for wheat.
Effect of Absorbent for Gas Purification Unit in Biomass Gasification Process with Downdraft Method
Authors: Amelia Shinta , Maryudi  , Aktawan Agus , Astuti Erna 
Published: May 2020

Abstract
The development of industry causes energy needs to increase. So that fossil energy reserves are increasingly depleting. This resulted in the growth of various alternative energies. One alternative energy that is being developed is biomass-based energy. Biomass is a renewable energy source that comes from plants both directly and indirectly. Indonesia is a country with a tropical climate that has a very large biomass potential. One of the methods that can be used in processing biomass is gasification, which is a process to convert solid biomass raw materials into fuels (syngas). The problem from the gasification process is the syngas produced has a low purity level. This is because there are still impurities that are contained in syngas. Therefore, a purification unit is needed in the gasification device. This research aims to make absorbents that can be used in gasification purification units. The types of absorbent used is coconut shell activated carbon. The pore structure of carbon is characterized by using an N2-sorption analyzer (Nova 2000, Quantachrome). Based on the results of characterization, it can be seen that the specific surface area of activated carbon absorbent from the coconut shell is 1320 m2/gram with an average pore diameter of 1.82 nm. The experiment device mainly consisted of gasification reactor, filter, and blower. The gasification reactor was installed to heating the biomass with the supply oxygen. The reactor had a height of 170 cm and a diameter of 50 cm in which the bagasse with the capacity of 15 kg/h was quickly burned. The gas filter contains the absorbent to clean the syngas product. The absorbent was installed in upper four holes. The blower was used to suck up the syngas. Some thermocouple and gas indicator were installed to monitor the condition in the system. The syngas production was analyzed by the GC/MS analysis. The effect of absorbent is to improve the syngas composition such as CO, H2, and CH4. The syngas contents in our experiment were CO, CH4, and H2 with a percentage of 9.294%, 1.348%, and 7.773%, respectively. These results are better than the previous research with the syngas contents are 7.891% of CO, 0.100% of CH4, and 0.889% of H2 because the previous research was not equipped the absorbent.
Process simulation of glycerol production from corn oil via transesterification
Authors: Trirahayu D A 
Published: May 2020

Abstract
Glycerol is widely use in the production of cosmetics, solvents for drugs, and lubricants. Glycerol can be obtained as by-product of biodiesel production from vegetable oils through the transesterification process. One of the vegetable oils with abundant raw material availability in Indonesia is corn oil. Each vegetable oil generally consists of triglycerides and free fatty acids (FFA) with different composition. The triglycerides in corn oil is round 95.59% (mostly trilinoleate and triolein), the rest are FFA (2.51%), phospholipid and phytosterol. The simulation process was designed using Aspen Hysys version 8.8. The corn oil composition was simulated as 54.30% trilinoleate, 41.35% triolein, and 3.85% oleic acid (FFA). The mole ratio of corn oil: methanol was set to 1: 20. The transesterification process was simulated using conversion reactor with conversion 98% at temperature 60°C and atmospheric. The process was followed with methanol recovery and glycerol separation from biodiesel. From the process around 99.04% of excessed methanol was recovered. Glycerol and biodiesel were separated using membrane. The simulation indicates that 100 kg/h corn oil can have converted into 101.1 kg/h green diesel and 10.41 kg/h glycerol with purity 99.85%.
Utilization of mangosteen extract as a corrosion inhibitor of carbon steel in acid environment (HCl)
Authors: Ngatin A , Sihombing R P 
Published: May 2020

Abstract
Utilization of mangosteen rind extract as carbon steel inhibitors in the environment of hydrochloric acid (HCl) 0.1M, 0.5M, and 1.0M. Extracts were carried out by extraction using ethanol solvent at a temperature of 600C with a time of 80 minutes. The variation of extract concentration (100 ppm to 1000 ppm in 3 days and the effect of time of corroding the carbon steel with the addition of 1000 ppm extract. Corrosion rate is calculated based on the difference in weight and corrosion products shown by microscope optics. The objective was investigated corrosion inhibition efficiency that could be prevented by mangosteen peel extract as inhibitor. The results showed inhibitory properties of mangosteen peel extract for three (3) days increased with increasing extract concentrations up to 76.53% in 0.1M HCl solution and 28.83% in 1.0M HCl solutions. For the addition of 1000 ppm mangosteen peel extract showed inhibitor efficiency reached about 90% at 3 days of corrosive time in HCl 0, 5 M, 87% in 1.0 M HCl solution, and 81% in 0.1 M HCl solution. The experiment showed that the process of diffusion of compounds in extracts on the surface of carbon steel and react with ferro ions (Fe2 +) to form chemical covalent coordination coordinate with a thickness of 76 µm was succesfully done.
Characteristic study of biodiesel mixtures from used oil and diesel oil
Authors: Aulia H N , Hidayat F N , Sriana T 
Published: May 2020

Abstract
Biodiesel is an alternative fuel for diesel machines. Used cooking oil is blended with diesel with a certain volume ratio to improve the characteristics. The characteristics of biodiesel can not be fully used by diesel engines because it doesn’t meet the standards so that its characteristics need to be improved. As for utilizing it, it must be blended with diesel oil. The purpose of this study is to improve the physical and chemical properties of biodiesel, knowing the percentage of biodiesel volume from used cooking oil with diesel oil so that it can be known the optimal ratio of biodiesel with diesel oil which is close to diesel fuel specifications. Characteristics as variables in this paper are density, kinematic viscosity, pour point, and flash point of the specified mixture. The results show that the kinematic viscosity and density of the biodiesel-diesel mixture increase as the biodiesel mixture increases. Mixtures with higher biodiesel content have higher flash points. Mixing diesel with used cooking oil biodiesel may be of no use compared to diesel, but it can help in adjusting the viscosity, density, pour point, and flash point values according to applicable regulations.
Control of aluminum corrosion in seawater environment by adding turmeric extract to the coating material
Authors: Heriyanto H , Permanasari A R , Wibisono A , Purnomoaji S G 
Published: May 2020

Abstract
Turmeric is one of the plants that contains antioxidant compounds called curcumin. Antioxidants in curcumin include flavonoids and tannins. Antioxidants can be used as corrosion inhibitors and paint additives. This study aims to utilize turmeric extract as an inhibitor and additive coating agent for aluminum metal in the seawater environment. Turmeric is extracted using a methanol or acetone solvent with a sample: solvent ratio of 1: 8. Phytochemical and DPPH (1,1-Diphenyl-2-Picrylhydrazyl) analyzes were performed. Testing of extracts as inhibitors and coating additives was carried out by varying the concentration and time of corroding. The results showed that the extract produced contained flavonoids and tannins through qualitative tests using 1% FeCl3 and 10% NaOH, each of which gave a blackish green and a blackish red color. Antioxidant activity was tested by the DPPH method in acetone and methanol, which respectively showed 4509 ppm and 2057 ppm. The testing of turmeric extract as a coating additive was immersed for five days and obtained the best level of 1% which produced the lowest corrosion rate of 0.0228 mmpy with a protection efficiency of 68.60%. Turmeric extract corrosion test as a coating additive was achieved within eight days with a corrosion rate of 0.0011 mmpy and a protection efficiency of 88.89%.
The effect of effective microorganisms-4 (em-4) on biogas yield in solid-state anaerobic digestion of corn stover
Authors: Shitophyta L M , Budiarti G I , Nugroho Y E , Hanafi M 
Published: May 2020

Abstract
Biogas production from various organic wastes such as corn stover can be used as an alternative fuel. Corn stover is one of the agricultural wastes that are widely generated in Indonesia. It contains cellulose which has the potential to be used as raw material for producing biogas. The biogas production process was carried out in solid-state anaerobic digestion (SS-AD), i.e., a biological process that occurs naturally by a microorganism that breaks down molecules of organic material with a total solid content greater than 15%. This research was aimed to investigate the effect of EM-4 concentration on biogas yield. The volatile solids (VS) reduction was also measured in this study. The results of the study showed that EM-4 concentration had a significant effect on biogas yield (p < 0.05). The positive linear relationship was found between EM-4 concentration and biogas yield. The highest biogas yield of 597.98 L/kg VS was obtained at EM-4 15%. The main source of biogas production during SS-AD of corn stover was the reduction of VS.
Effect of brine mass rate on pressure drop and dirt factor in evaporator design
Authors: Wuryanti S , Maridjo M , Mudawari A 
Published: May 2020

Abstract
Geothermal is one of the most significant natural resource potentials in Indonesia. One power plant that utilises geothermal steam as its energy source is PLTP. Geothermal steam that has passed through the geothermal power plant separator to move the turbine while the residual waste (brine) with a high enough temperature has the potential to be a source of heating to produce electrical energy in the Kalina cycle generator. Using brine, before entering the turbine, it must first become airtight in the evaporator. Evaporator design requires initial parameters namely brine fluid flow rate and ammonia-water flow rate, shell dimensions and tube dimensions as well as the number of passes, then performs the design calculation steps until the calculation results meet operating requirements, namely the pressure drop value and the dirt factor. Different variations of brine rate will produce different pressure drops and soil factors. Brine rate variations are 11 kg/s, 22 kg/s, 33 kg/s, 44 kg/s, 55 kg/s and 66 kg/s show the lowest pressure drop of 0.098 bar and the most massive 0.68 bar, and the smallest dirt factor is 0,002 (hr)(m2 °C)/Joule moreover, the largest is 0,00019 (hr)( m2 °C)/Joule.
Impact evaluation of Cilember River normalisation to PURBALEUNYI Toll Road using two dimensional model HEC-RAS
Authors: Budianto B S , Djuwadi D , Muttaqin A S , Karnisah I , Astor Y 
Published: May 2020

Abstract
Cilember River flows from North to South of Cimahi and crosses PURBALEUNYI Toll Road in downstream. Therefore normalization of Cilember River Cimahi can impact the PURBALEUNYI Toll road. Hydraulic simulation carried out to determine the impact and formulate the mitigations alternatives. The study was conducted based on Detail Engineering Design Data for Cilember Normalisation Program prepared by Citarum River Authority as a base data. Two-dimensional HEC-RAS model was used to simulate the impact of the river normalization program. The model also used to evaluate the alternatives (detention pond, diversion of flows) to minimize the impact of the Cilember normalization program to PURBALEUNYI Toll road. Applying 10 year return period and HEC-RAS simulation, with an existing condition, 26 505 sqm area is inundated mostly in the North area of Toll Roads. After the normalization program, the inundation area shifts to the south area, including Toll road. The further simulation shows that normalization of the river can reduce inundation area to 7 993 sqm. Simulation of combination between detention pond and diverting the excess flow of Cilember to Kali Malang inundated area occurs, but it does not affect the toll road.
Adi Sumarmo airport train station: Transit and connectivity
Authors: Fajrillah M L , Aryanti T , Siswoyo S 
Published: May 2020

Abstract
The growth of people’s needs for transportation facilities in Indonesia has urged the government to build a particular space that could accommodate, facilitate, and contain people’s fast and massive movements. Urban planning needs to be oriented to transit activities to accommodate people’s moving behavior. Surakarta’s Adi Sumarmo International Airport has been one of the government’s plans for developing infrastructural facilities to connect essential areas in Central Java. As an international airport, Adi Sumarmo International Airport is expected to facilitate people’s movement to the city of Surakarta and other cities nearby. This article discusses the design of an airport-train station, employing a transit-oriented development approach. The design implements the concept of walkability, mixed use neighborhood, and an inclusive environment.
Optimizing maintenance of electrical components with BIM and web-based inputs to improve safety performance in government green building
Authors: Dewi S , Latief Y , Machfudiyanto R A 
Published: May 2020

Abstract
A green building with proper maintenance will have higher energy efficiency and longer lifetime, as damages to building utilities can be minimised. One of the vital utilities are electrical components. Damages to electrical components may have fatal consequences such as short circuit or fire. This research aims to improve the maintenance of electrical components of green building. A case study is taken from a government green building for electrical components, in order to meet the building reliability requirements which consist of safety, health, comfort, and convenience. Maintenance system which is Work Breakdown Structure (WBS) level 4 of building maintenance integrated with information systems and Building Information Modeling (BIM) are influential factors for building maintenance performance. The research methods used are archival analysis, case study, survey, expert judgement, and statical analysis. This research generates product of web based information system integrated with BIM, and also mathematical model that enhance the maintenance performance of government green building for electrical components would become more effective and efficient especially for safety performance.
Travel behaviour regression modeling of urban housewives in the great metropolitan Bandung area
Authors: Maryati S , Putro H P H , Hayati A 
Published: May 2020

Abstract
The Millennial Situation and Condition are now changing the lifestyles of the urban societies, especially for women. It is also changing their travel behaviour to do their daily activities to meet their family needs. Including in The Great Metropolitan Bandung Area, the urban women have high demand for their daily journey and tend to increase. By the theme of Gender Mainstream philosophy, urban women have the freedom to get their accessibilities of going anywhere with their own transportation modes, including non-working urban women or as housewives in the region of Bandung. As WRI (2015) said that was more than 50% of women’s mobility have a complex daily trip to meet their needs by doing their daily activities. It was done to meet the needs of family and home care in the terms of rising family’s welfare. While less than 60% of men’s travel behaviour have a simple trip. This kind of condition is very interesting to be analysed, especially in The Great Metropolitan Bandung Area. This study explains how complex the daily travel behaviour of non-working urban women and as housewives with activities based approach that were done outdoor in a week. The quantitative data that is performed by socioeconomic and household demographic variables serve as the basis to measure the independent variables affecting family welfare, as well as the type, time, and duration of each daily activities and daily traveling data of non-working urban women. Using Clustering Methods approach to describe the width of research area, we could find the differences of models by Regression Analysis. So, we have 3 kinds of Regression Models to figure out the each of cluster from 3 Clusters that we find by Clustering Method in The Great Metropolitan Bandung Area. The result of this study could be used to make a change of city transportation policy and also to analyse the economic potential area by the models for the government officers and the business owner to increase their profit. By the regression models result, it could be used to estimate many variables ini the future to increase the economic growth of the City from the transportation by user’s perspective.
Enhancing safety and comfort through mechanical component maintenance performance on green building using BIM-based information system
Authors: Riza I W , Latief Y , Machfudiyanto R A 
Published: May 2020

Abstract
The reliability of functioning mechanical components has major implications not only for the ease of use, lowering maintenance cost, avoiding loss of time and preserving safety factor but also for achieving green buildings mission namely emission and energy reduction. Failure in maintenance phase of mechanical components can adversely affect the achievement of the mission. Problems that occur are fragmented data, undocumented data, slow responses of human resource, and unscheduled maintenance. As a result, the massive budget spent in the green building construction phase is in vain. The purpose of this study is to improve the performance of maintenance of government green buildings in mechanical components by developing an information system that integrated with Building Information System (BIM). The case study studied was the Ministry of Public Works and People’s Housing Republic of Indonesia. The research methods used are literature reviews, case studies, system development and statically analysis. This study uses a Work Breakdown Structure (WBS) in managing data dynamically using BIM, which is integrated with web-based information systems. The result in this study explained that HVAC system, vertical transportation, BIM and information system has proofed that these variables could enhance the performance of mechanical components maintenance in green building which are safety, health and comfort.
Flexural strengthening of composite bridge glued laminated timber beams-concrete plate using CFRP layers
Authors: Mujiman M , Igustiany F , Hakiki R 
Published: May 2020

Abstract
The timber bridge design although economical, often has difficulty producing enough rigidity so that a solution is needed to solve it. The use of CFRP (Carbon Fiber Reinforced Polymer) as a reinforcement of structural elements if properly designed and implemented can produce an effective and efficient composite structure. The experimental study aims to analyse the strength, stiffness and ductility of flexural strengthening composite bridge glued laminated timber beams-concrete plates using CFRP layers. The dimensions of the composite glued laminated timber beams 100/180 mm and concrete plate 75/300 mm with a length of 2,480 mm. The number of specimens is 3 composite glued laminated timber beams-concrete plate consisting of 1 test beam without CFRP reinforcement, 1 test beam with one layer CFRP reinforcement, and 1 test beam with three layer CFRP reinforcement. Experimental testing of flexural loads is done with two load points where each load is placed at 1/3 span length. The test results show that the strength of composite laminated timber beams glued - concrete plates BN; BL-1; BL-2 in a row 81.32; 82.82; 82.69 kN/mm; stiffness in a row 7.51; 8.22; 6.32 kN/mm and successive ductility of 16.67; 28.83; 20.21.
Effect of temperature rise against durability and behaviour of ground granulated blast furnace slag concrete
Authors: Kusuma Y , Nursyafril N , Ruchiyat I , Harahap A H S 
Published: May 2020

Abstract
Concrete which affected with high temperature will lost its strength significantly by 60%. To overcome this problem is utilizing steel industry waste, that is Ground Granulated Blast Furnace Slag (GGBFS) which is used as a substitute for cement in concrete mixtures. The properties of GGBFS which is cementitious same as cement, so that it can fulfil the function of cement. In this research, GGBFS concrete and normal concrete with strength of concrete is 30 Mpa and both types of concrete will be burned at a temperature of 600°C for 2 hours. After that, characteristics strength of concrete will be tested to GGBFS concrete and normal concrete in each concrete before being burned and after being burned. The result of this research, there was an insignificant increase in strength of concrete with GGBFS as a substitute for cement by 40%. The average compressive strength of GGBFS concrete before and after being burned was 30.48 MPa and 11.16 MPa, compared to normal concrete which was 30.06 MPa and 9.76 MPa. Increasing also happened at the result of flexural test, wich is initial crack at GGBFS concrete occur in greater deflection and load than normal concrete.