Page 3 (data 61 to 90 of 1039) | Displayed ini 30 data/page
<< PREV 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 NEXT >>

61	Chemistry	ABS-1020
Isolation, Characterization, and Antibacterial Assay of Friedelin from Garcinia latissima Miq. Leaves Neneng Siti Silfi Ambarwati1, Berna Elya2*, Amarila Malik2, Muhammad Hanafi3,4, Hanita Omar5 1Cosmetology Department, Faculty of Engineering, Universitas Negeri Jakarta, Jl. Rawamangun Muka, East Jakarta 13220, Indonesia. 2Faculty of Pharmacy, Universitas Indonesia, UI Depok Campus, Depok 16424, Indonesia. 3Research Center for Chemistry, Indonesian Institute of Sciences (LIPI), Kawasan PUSPIPTEK, Serpong, Tangerang, 15314, Indonesia. 4Faculty of Pharmacy, University of Pancasila, Srengseng Sawah, Jakarta, Indonesia. 5Chemistry Division, Centre for Foundation Studies in Science, University of Malaya Abstract Background. Garcinia latissima Miq. (Clusiaceae) grows on the island of Seram Maluku and Papua, but was cultivated in the Bogor Botanical Garden since May 11th 1994. Previous research has been done that ethyl acetate extract of G. latissima Miq. leaves with 2% concentration in dimethyl sulfoxide against Bacillus subtilis used agar diffusion method gave inhibition zone diameter 7.68 mm. The minimum inhibitory concentration (MIC) of the extract against B. subtilis was 5,000 ppm and the minimum bactericidal concentration (MBC) was 10,000 ppm. Purpose. The purpose of the study was to get isolate from G. latissima Miq. leaves ethyl acetate extract and to understand its activity against B. subtilis. Methods. The isolation was performed by open column chromatography, recrystallization, preparative thin layer chromatography and the isolate antibacterial assay by microdilution method. Spectroscopic characterization using ultra violet spectroscopy (UV-Vis), infra red spectroscopy (FTIR), 1H-NMR, 13C-NMR, DEPT, HSQC. Result. The isolated compound was white crystal, soluble in chloroform and insoluble in n-hexane, ethyl acetate. The melting point of the isolated compound was 262-264oC. IR spectrum showed strong signals for C-H stretching of methyl groups and carbonyloxygen (C=O). The based on NMR data, the chemical shifts of chemical compounds from the isolate was compared with the literature showed that the isolate was friedelin. The MIC of friedelin against B. subtilis was 2,500 ppm. Keywords: Garcinia latissima Miq., isolation, characterization, antibacterial, Bacillus subtilis PermaLink | Plain Format | Corresponding Author (Neneng Siti Silfi Ambarwati)

62	Chemistry	ABS-253
Reinforcement of chitosan film using cellulose isolated from grass (imperata cylindrica) Nurradhiyah Az-Zahra, Rahmi*, and Surya Lubis Chemistry Department, Syiah Kuala University, Darussalam, Banda Aceh, 23111, Indonesia. *rahmi[at]fmipa.unsyiah.ac.id Abstract Cellulose from grass (imperata cylindrica) had been used as reinforcement in chitosan film preparation. Cellulose was obtained from grass through hydrolysis process. Hydrolysis was conducted with different concentration of sulfuric acid at room temperature for 2 h. The results show that the highest crystallinity of cellulose was obtained at sulfuric acid concentration of 40% (v/v) on hydrolysis process. The isolated cellulose with the highest crystallinity was used on chitosan film preparation. Mechanical test shows addition of cellulose into chitosan film improved the tensile strength. The FTIR analysis was used to define the interaction between components. XRD analysis shows the addition of cellulose decrease the crystallinity of chitosan film. Keywords: chitosan film; cellulose; grass; hydrolysis; crystallinity; tensile strength PermaLink | Plain Format | Corresponding Author (Rahmi Rahmi)

63	Mechanical Engineering	ABS-1
Feasibility Study of Installation Photovoltaic System on UNSAM Campus, Langsa, Aceh Hamdani Umar (a*), Munira Amudy (b) and T.A Rizal (c) a) Mechanical Engineering Department, Syiah Kuala University, Banda Aceh, 23111, Indonesia. hamdani[at]unsyiah.ac.id b) Planning Section, Samudra University, Kota Langsa, Aceh, 24416, Indonesia. c) Mechanical Engineering Department, Samudra University, Kota Langsa, Aceh, 24416 Indonesia. Abstract All renewable energy sources are land intensive. A solar photovoltaic (PV) system requires a lot of spaces, and roofs of buildings are perfect places for installation of campus-wide PV system since most universities cannot afford to waste their land for PV modules. There are 8 buildings on the University of Samudra (UNSAM) campus with 22,000 m2 of roof areas that are structurally suitable for solar photovoltaic. UNSAM is located in Kota Langsa, Aceh, where an average of 360 days, which is equivalent to approximately 7,860 hours of sun shine is annually present. The average annual insulation at this location is about 5.0 to 6.5 kWh/m2/day. This geographical information suggests that solar resource at this location. This study focused on the economic feasibility of solar photovoltaic systems on the University of Samudra campus. The result of this study will be used to analyze and further develop the feasibility study of PV systems for universities in the Aceh region, which share similar characteristics of climate and economic factors. Keywords: Feasibility study, Photovoltaic, Campus PermaLink | Plain Format | Corresponding Author (Hamdani Umar)

64	Mechanical Engineering	ABS-3
Effect of Near Dry Machining (NDM) on surface roughness through Sustainable turning of Mild carbon steel using coated carbide Rusdi Nur, Muhammad Arsyad Suyuti, Muhammad Iqbal Mukhsen Politeknik Negeri Ujung Pandang Abstract Sustainable production as a global word, content important elements on all the fields as well as machining processes. Turning is one of the most fundamental and indispensable processes of metal removal in industry. Increasing pollution preventing initiatives globally and consumer focus on environmentally conscious products has put increased pressure on industries to minimize or eliminate the use of cutting fluids. The use of Near Dry Machining (NDM) in machining operation is one of the most effective strategies in this direction to achieve sustainable machining system. This study was purpose to determine the influence of NDM coolant system on surface roughness when turning of mild carbon steel, include power demand. A detailed comparison has been made with dry cutting to assess the process performance on the basis of surface roughness and power demand. The results indicate that providing reduction on surface roughness and power demand more effectively than dry cutting at high speed conditions, thereby to achieve sustainable machining system. Keywords: Sustainable Turning, NDM, Surface Roughness PermaLink | Plain Format | Corresponding Author (Rusdi Nur)

65	Mechanical Engineering	ABS-522
Finite Element Analysis of Miura Origami Structure under Uniaxial Compressive Load Samuel Christian Hidajat (a), Mia Rismalia (a), I Gede Raditya Permana (a), Muslimin (b), Farid Triawan (a*) a) Faculty of Engineering and Technology, Sampoerna University, Jakarta 12780, Indonesia *farid.triawan[at]sampoernauniversity.ac.id b) Department of Mechanical Engineering, Politeknik Negeri Jakarta, Depok, Indonesia Abstract This paper presents the finite element analysis (FEA) of Miura origami structure under the uniaxial compressive loading condition. The FEA model is developed under elastic-perfectly plastic material. Investigation on the compressive deformation characteristic and elastic modulus with three varied parameters, i.e. angle, thickness, and density of the Miura origami structure is conducted. The Abaqus software is used to conduct the simulation of compression test. The simulation result is then compared with and examined to the experimental data. The results of the analysis can be used for predicting the mechanical behavior of origami-shaped structure such as for designing an impact energy absorber and vibration damper. Keywords: finite element analysis, Miura origami, uniaxial loading, deformation characteristic, material properties, elastic-perfectly plastic material. PermaLink | Plain Format | Corresponding Author (Mia Rismalia)

66	Mechanical Engineering	ABS-533
Study on the Compressive Behavior of Miura-Origami Lattice Structure I Gede Raditya Permana (a), Mia Rismalia (a), Samuel Christian Hidajat (a), Asep Bayu Dani Nandiyanto (b), Farid Triawan (a*) a) Faculty of Engineering and Technology, Sampoerna University, Jakarta 12780, Indonesia *farid.triawan[at]sampoernauniversity.ac.id b) Departemen Kimia, Universitas Pendidikan Indonesia, Jl. Dr. Setiabudi no 229 Bandung 40154, Indonesia Abstract Miura-origami pattern has taken interest of many engineers and mathematicians due to its unique foldability and wide range of engineering applications. However, its mechanical behavior is yet to be fully explored, especially when it is made by additive manufacturing (3D printing) method. In this paper, the compressive behavior of 3D printed lattice structure using the Miura-origami pattern is investigated. Polylactic Acid (PLA) material is used to make the specimen with various printing parameters, i.e infill pattern and density. Moreover, three kind of origami patterns with different folding angle and wall thickness are applied. Finally, the elastic, plastic, and fracture deformation behavior under compressive load is examined. The result is useful to develop a finite element model which can be utilized to comprehensively explore the mechanical behavior under complicated loading condition for various kind of engineering applications. Keywords: miura-origami, 3D printing, finite element analysis, polyactic acid (PLA), deformation characteristic, material properties PermaLink | Plain Format | Corresponding Author (I Gede Raditya Permana)

67	Mechanical Engineering	ABS-30
Efficiency Analysis of Refrigerant Work Fluid in the Organic Rankine Cycle (ORC) as an Energy Generating Machine Electricity 1 kW Scale muhamad yunus abdullah, prabowo, bambang sudarmanta INSTITUT TEKNOLOGI SEPULUH NOPEMBER Abstract Today the supply of fossil energy resources which is increasingly depleting will have a significant impact on every aspect of life in Indonesia. One attempt to overcome this problem by using the Organic Rankine Cycle (ORC) Cycle System. The types of refrigerants used in this study were R141 b, R123 and R245 fa using Aspen plus software simulation. This research focused on journal review and using aspen plus software simulation using the working fluid refrigerant R141b, R123, and R245fa on the ORC as a 1 kW scale electric energy generating machine. The results obtained from the simulation using aspen software plus Organic cycle Rankine Cycle (ORC) using a working fluid refrigerant R141b, R245fa, and R123 at a pressure of 3 bar to a pressure of 11 bar at a temperature of 95 degrees Celcius. The maximum efficiency produced is 8.65 %, 7.79 %, and 8.36 %. Turbine power produced 1005 watts, 896 watts and 770 watts From the simulation results used in the Organic Cycle Rankine Cycle R 245fa has the efficiency value that is best used as a 1 kW electric energy generating plant with an efficiency value of 8.65 %. Keywords: Aspen Plus Software; Turbine; Evaporator; Condenser; Pump PermaLink | Plain Format | Corresponding Author (Muhamad Yunus Abdullah)

68	Mechanical Engineering	ABS-31
Passive Flow Control on 90-Degree Square Elbow by Varying the Circular Turbulator Gap Randi Purnama Putra, Sutardi, Wawan Aries Widodo, Rizkia Putra Pratama Institut Teknologi Sepuluh Nopember Abstract The ducting system has considerable energy losses in channeling cold air in a tall building. At the square elbow 90-degree, the pressure drop due to friction loss, separation loss, and secondary flow. An increase in pressure drop can increase the amount of energy consumption needed. The method identified in reducing this energy loss is by using passive flow control. This study aims to identify the characteristics of the fluid in the ducting with variations in the circular turbulator gap. The variation of the gap between circular turbulator and 90-degree inner elbow (g/Dh) is 0.01 - 0.05. The ducting model used is a square duct with a hydraulic diameter of 125 mm. The results showed that the addition of circular turbulator g/Dh = 0.02 reduced the pressure drop by 20.52 percent. The use of circular turbulator on the 90-degree inner elbow causes the phenomenon of separating and reattaching. The shear layer deflected from the circular turbulator meets the free stream momentum so that it has high turbulence intensity. This fluid momentum reattaches the curved surface of the 90-degree inner elbows and can resist wall shear stress. Keywords: Passive Flow Control, Square Elbow, Circular Turbulator, Pressure Drop PermaLink | Plain Format | Corresponding Author (Randi Purnama Putra)

69	Mechanical Engineering	ABS-34
Numerical Studies of Influence Angle of Attack of Configuration Fairing Flap Track types Naca 4412 and NACA 6412 Handrico Ramelan Pratama Handricoramelanpratama[at]gmail.com Abstract Stability control is one of the important factors in flight, wings of the world known function change of air that flows into a lift and drag. Fairing Flap Track is known to increase the stability controls on the wings. This research discuss our results to see configuration the Fairing Flap Track to wings, fairing inspired by Sailfish fins and Blue Shark fins. This studies of configuration influence of fairing flap track on angle of attack 0 degree to 35 degree of the speed 100 km/h type Naca 4412 and NACA 6412. This research is knowing coefficient drag, coefficient lift and lift to drag ratio using software computational fluid dynamic (CFD). The results of simulation studies it is knowing that after mounting the fairing that the value coefficient of lift and coefficient of drag of the NACA 6412 of the higher than types of NACA 4412. The second model of airfoil and fairing knowing decrease the value coefficient of lift on 20 angle of attack. Shifting the point of stagnation toward lower side due to angle of attack. Fairing Flap Track has a major influence on the reducing drag caused by the effect of compressible. Keywords: Angle of attack, coefficient drag, coefficient lift and lift to drag ratio PermaLink | Plain Format | Corresponding Author (Handrico Ramelan Pratama)

70	Mechanical Engineering	ABS-38
Modeling of Oil Palm frond Gasification process in a multi-stage downdraft gasifier using Aspen Plus Arif Rahman Saleh, Bambang Sudarmanta, Hamzah Fansuri, Depi Rustam Ependi Institut Teknologi Sepuluh Nopember Abstract Oil palm plantations produce waste that has not been used so far, namely oil palm fronds. This waste can be converted into energy in the form of gas using gasification technology. This study aimed to model the gasification process using Aspen PLUS in a multi-stage gasifier by inputting air at the pyrolysis and oxidation zone. The prediction of the modeling results is compared with the results of an experimental study of oil palm frond gasification from the literature. The influence of variations in air ratio (AR) between the pyrolysis and oxidation zones (0% - 50%) and the effect of gasification temperature from 700oC - 1000oC on the syngas composition were analyzed. Besides, the equivalent ratio (ER) is also varied from 0.3 - 0.5 to get the optimum syngas composition. From the modeling results, the rate of CO production is increased along with the increase in the temperature of pyrolysis while CO2 and char decrease. Besides, H2O and H2 also increase because the significant amount of inherent moisture is released from the feedstock. However, CH4 is unpredictable. Overall, Aspen PLUS modeling in this study can be used to obtain optimum operating conditions with variations of ER and AR. Keywords: oil palm frond, multi-stage gasifier, gasification, syngas PermaLink | Plain Format | Corresponding Author (arif rahman saleh)

71	Mechanical Engineering	ABS-1076
RE-DESIGN TONY KART MITOX GOKART MODEL (Re-Design Analysis of Chain-Drive Components) Ibnu Mubarak Departemen Pendidikan Teknik Mesin Universitas Pendidikan Indonesia Abstract The purpose of this study was to determine the type of chain suitable for use on karts, besides that this study aimed to determine the safety factors of chain hinges and sprocket gears used in redesigned karts. The method used in this study uses descriptive analysis method, namely by describing the data about the chain wheel on karts, after describing the data, the data are analyzed theoretically about the forces that occur in the chain wheel and the safety of the use of chain wheels used in redesigned karts. After analyzing the data, the results show that the chain wheels on the redesigned kart are safe to use. This is indicated by the acquisition of a hinge safety factor value of 4.02. The results of this study have an impact on the use of chain wheels on the redesigned karts in the safe category to be used for kart racing purposes. Keywords: Chain-Drive,RE-DESIGN TONY KART MITOX GOKART MODEL,kart,safety factor PermaLink | Plain Format | Corresponding Author (Ibnu Mubarak)

72	Mechanical Engineering	ABS-313
High-pressurizing green algae in third generation bioethanol production H.B. Aditiya*, H.C. Theofany, M. Yheni Department of Mechanical Engineering, Sampoerna University, Jl. Raya Pasar Minggu, Kav 16, Jakarta 12780, Indonesia *aditiya.harjon[at]sampoernauniversity.ac.id Abstract The effects of fossil fuel combustion are famously concerning. 70% of the global production of carbon monoxide is accounted from transportation sector; the sector in which fossil fuel is popularly being continuously used. As one alternative fuels, bioethanol is a renewable fuel which have attracted many researchers in the pursuit of lowering the dependency on fossil fuel and its negative effects to the environment. In third generation bioethanol production, green algae are deemed to carry high potential as the feedstock due to its ampleness, especially in a tropical country such as Indonesia. In this study the ability to produce fermentable sugars from green algae was observed through high-pressurization treatment. Different treatment pressures were achieved through varying temperature set in the autoclave: 110, 120 and 130oC. The recorded pressure was up to about 500 kPa, and this treatment was also compared with non-pressurizing production method. Samples were analyzed for reducing sugars content through DNS method. Since simple sugars are essential in the fermentation stage, the produced sugars from green algae are the indication of potential as the feedstock in bioethanol production. Keywords: Biofuel; Renewable energy; Bioethanol PermaLink | Plain Format | Corresponding Author (Aditiya Harjon)

73	Mechanical Engineering	ABS-572
A Comparative Investigation of Biomass Pyrolysis on Connecting Tube Performance for Liquid-smoke Production Herman Saputro(1,2), Bah Evan* (2), Desi Nur Liana(1), Bangun Sang Karsa(2) (1)Department of Vocational Teacher of Education, Sebelas Maret University, Jl. Ir. Sutami 36A, Surakarta, Indonesia (2)Department of Mechanical Engineering Education, Sebelas Maret University, Jl. Ahmad Yani No.200, Pabelan, Surakarta, Indonesia Abstract The potential energy analysis of biomass waste as a sustainable source of energy continues to increase with various design to obtain maximum efficiency. Modification of the type of material, diameter, and length of the connecting tube between the reactor and the condenser can increase its effectiveness. The optimal parameter search for the connecting tube that produces liquid-smoke are carried out using galvanized pipes and stainless-steel pipes with variations in diameter ¼ inch, ¾ inch, and length 1 meter, 0.5 meters. Testing the quantity of liquid-smoke results on sugar palm waste samples was carried out at 400 C for 60 minutes by seeing an increase of the amount of liquid-smoke. The results of the study show variations in size and type of tube affect the product yield of the pyrolysis process. Stainless-steel pipes have better performance to produce liquid-smoke. The shorter the length of the pipe increases the quantity of liquid-smoke, but the smaller the diameter of the pipe decreases the quantity of liquid-smoke. This paper discusses in more detail the comparison of the performance of connecting tube by modifying the type of material, the length, and the diameter of the pipe. Keywords: Biomass pyrolysis, connecting tube, liquid-smoke PermaLink | Plain Format | Corresponding Author (Desi Nur Liana)

74	Mechanical Engineering	ABS-829
Thermal Properties of Beef Tallow/Coconut Oil Bio PCM Using T-History Method for Wall Building Applications Muhammad Amin (a*), Hamdani (b), Fazri(a), Razali Thaib (b) a) Department of Mechanical Engineering, Universitas Samudra, Kota Langsa, 24416, Indonesia b) Department of Mechanical Engineering, University of Syiah Kuala, Banda Aceh, 23111, Indonesia Abstract Thermal energy storage using Phase Change Materials (PCM) is now widely applied to wall builds. Generally, PCM used for applications on walls building has a melting point of 0-65 oC. Beef tallow and coconut oil is a type of organic PCM known as Bio PCM needs to characterize by using the T-History Method. The T-History method is more accurate than DSC. This study aimed to determine the thermal properties of beef tallow/coconut oil PCM using the T-History method. The beef tallow and coconut oil as bio PCM material used in this study with the variation is respectively: 100%, 70+30%, 60+40%, and 50+50%. Tests are carried out using the T-History method. From the results of testing and analysis obtained supercooling temperature, melting temperature, specific heat, and latent heat for bio PCM beef tallow/coconut oil. The effect of adding coconut oil mixture to beef tallow caused a decrease in melting temperature and supercooling temperature, while the specific heat and latent heat of bio PCM of beef tallow/coconut oil ranged from 2.96-2.19 kJ/kg.oC and 101.05-72.32 kJ/kg. The result obtained that this bio PCM material of cow beef tallow/coconut oil can apply, as additional material in wall building applications. Keywords: Thermal properties, Beef tallow/coconut oil, T-History method, Phase change material (PCM) PermaLink | Plain Format | Corresponding Author (Muhammad Amin)

75	Mechanical Engineering	ABS-832
THE PIPE OF SUPER FAST HEAT TRANSFER Ratu Amilia Avianti* and Nugroho Gama Yoga Departement of Mechanical Engineering Education, Engineering Faculty, State University of Jakarta *email : avianti.raa[at]gmail,com Abstract The development of increasingly sophisticated technology will have positive and negative impact, some equipment will result in greater heat compensation. This heat dissipation must be removed immediately to keep the device working properly. Therefore, equipment is needed that can move this heat quickly and large capacity. In addition to be discarded, heat from potential sources can also be utilized. One heat transfer device that does not require energy as a driver is a heat pipe. This tool is very potential for the application, but not yet widely used especially in Indonesia, then in this paper will be described the process from planning to testing. The heat pipe in the material selection is strongly influenced by the plan of its use, both its physical components on the form of pipes, axis structures, and working fluids as well as the operating range of the heat pipe. Some types of heat pipe and the use of materials will be different to the manufacturing process. One of the heat pipe tests applied to the solar collector showed a positive result. Keywords: heat transfer; fast; pipe PermaLink | Plain Format | Corresponding Author (Ratu Amilia Avianti)

76	Mechanical Engineering	ABS-78
Comparison of Predictive Performance and Measurement of Off-Grid 15 kWp Solar Power Generation in Aceh Tamiang Razali Thaib (a*), Samsul Rizal (a), T. Azuar Rizal (b) (a) Department of Mechanical Engineering, Faculty of Engineering, Universitas Syiah Kuala, Banda Aceh 23111, Indonesia *) razalithaib[at]unsyiah.ac.id (b) Department of Mechanical Engineering, Faculty of Engineering, Universitas Samudra, Kota Langsa, 24416, Indonesia Abstract In 2015, the Government through a special allocation fund has finished constructing an off-grid 15 KWp off-grid solar power plant in Paya Tampah Village, Aceh Tamiang district. Currently, it has been utilized by at least 50 heads of local transmigration families. With the lighting of renewable energy is expected to provide more value to improve peoples living standards and support educational activities in order to continue to run. The construction of this centralized solar power plant is based on the ministerial regulation of energy and mineral resources of the republic of Indonesia, year 2015 no.10, on technical guidance on the use of special allocation funds for rural energy in 2015. The long term reliability of concentrated solar power plants is highly dependent on on-site measurements because of the uncertainty in some of the ever-changing data such as irradiation value, drought rate, which can cause significant power losses and then affect the estimated cost of PV (kWh). With the aim of upgrading capabilities in off-grid solar power plant planning especially in the province of Aceh, this paper will outline in detail the comparison of the results of calculating the performance of off-grid 15 KWp off-grid solar power with system performance measurement results after 2 years of operation. Performance calculations were performed with PVsyst software and software HOME. From the measurement results obtained the total power generated by off-grid solar power plant is 12 kWp and used by 45 households. The cost incurred during installation is USD 300 thousand. From the simulation results with the same technical specifications obtained cheaper cost with the output power of 15 kWp. The results of this study are expected to be used by local governments to be a benchmark on the future planned off-grid solar power plant planning. Keywords: Simulation, Performance, Measurement, Off-Grid PV PermaLink | Plain Format | Corresponding Author (Razali Thaib)

77	Mechanical Engineering	ABS-79
Utilization of Beeswax/Bentonite as Energy Storage Material on Building Wall Composite Razali Thaib (a), Hamdani (a*), T. Azuar Rizal (b) (a) Department of Mechanical Engineering, Faculty of Engineering, Universitas Syiah Kuala, Banda Aceh 23111, Indonesia * hamdani[at]unsyiah.ac.id (b) Department of Mechanical Engineering, Faculty of Engineering, Universitas Samudra, Kota Langsa, 24416, Indonesia Abstract Indonesias energy consumption pattern for housing sector for heating or cooling reached 43%, water heater 27%, lighting 3.4%, appliances 26.6%. As for the use of electrical energy, reaching 50% of the total energy needs is absorbed in the building sector. Therefore, the residential sector has a very dominant role in electricity consumption, whether for lighting purposes, the use of household appliances as well as for conditioning the room. Indonesia, as a developing country, will undoubtedly move to improve the lives of its population. It will affect and induced a shift in energy pattern used by the community, whereby most of it will be used to increase the comfort of the space, whether by improving the air conditioning system, the lighting system, or water heater. On the other side, the current energy consumption pattern for the commercial building sector reaches 50-60% for air conditioning systems, 30% for lighting and the rest to drive other machines. The combination of building materials and Phase Change Materials (PCM) is an efficient way to increase the thermal energy storage capacity of building components. The technique of combining with encapsulation-PCM composite form is the most straightforward method, practical and economical method, and has attracted the interest of many researchers in the last decade. This paper will discuss the results of developing numerical modeling for simulation of thermal energy storage on composites equipped with macro-encapsulation PCM. The simulation is conducted using the EnergyPlus software. Furthermore, the validation of modeling result will later be conducted through comparison of simulation result with field test result. In this study used beeswax as a phase change material. Beeswax has a moderate melting temperature, which is placed within the indoor thermal comfort range and the bentonite clay will be used as a binder. From the results of numerical analysis of the use of PCM on the walls of the building can be concluded that PCM is able to store heat energy from solar radiation, thus reducing energy consumption for cooling the room. Increasing the thermal conductivity of PCM will increase the value of the overall heat transfer coefficient of the wall resulting in increased energy consumption for room cooling Keywords: Phase change material, Beeswax, Bentonite, Heat storage PermaLink | Plain Format | Corresponding Author (Razali Thaib)

78	Mechanical Engineering	ABS-336
Microwave irradiation pre-treatment in third generation bioethanol production from tropical green algae H.C. Theofany(1), M. Yheni(1), H.B. Aditiya(1)*, N.S. Sepwin(2), *aditiya.harjon[at]sampoernauniversity.ac.id (1) Department of Mechanical Engineering, Sampoerna University, Jl. Raya Pasar Minggu, Kav 16, Jakarta 12780, Indonesia (2) Department of Applied Physics, Sampoerna University, Jl. Raya Pasar Minggu, Kav 16, Jakarta 12780, Indonesia Abstract Through centuries the side effect of the massively growing of population is the energy demand and consumption. As a result of this, the world energy used from the non-renewable fossil fuel has reached 80%. To counter this, researchers have found alternatives for this fossil fuel; and bioethanol is one of the alternative and sustainable options. One source of bioethanol that is believed carrying high production potential is photosynthetic algae or green algae. In this study, Chlorophyta (Green Algae) was hydrolyzed using microwave irradiation. Operation Mode (OM) was varied to observe its effect during the hydrolysis stage. Further, hydrolysis time (t) was also selected as the variable in this study to examine the result of reducing sugar. From the result of this experiment, it is projected that the sugar produced from hydrolysis assisted by microwave irradiation would bring a high-quality bioethanol production. Also, from this study, it would exhibit the great potential of bioethanol from green algae as the fossil fuel substitute in order to create a more sustainable and environmentally friendly energy source. Keywords: Biofuel; Renewable energy: Bioethanol PermaLink | Plain Format | Corresponding Author (Theofany Harley Chriswardana)

79	Mechanical Engineering	ABS-1104
Immersion Cooling for The Next Cooling Technology for Data Center: A Review Ilham Wahyu Kuncoro(a), Nugroho Agung Pambudi(a,*), Muhammad Kunta Biddinika(b), Indah Widiastuti(a), Miftah Hijriawan(a), and Kukuh Mukti Wibowo(a) (a) Mechanical Engineering Education, Universitas Sebelas Maret, Surakarta *agung.pambudi[at]staff.uns.ac.id (b) School of Environment and Society, Tokyo Institute of Technology Abstract The development of the world internet usage continues to increase from time to time. It is recorded that 46% of the worlds population has become internet users and generates data traffic of 8 zettabytes every day. This increase has triggered the growth of data center infrastructure as processing, storage and communication system in the digital world. The data center itself has contributed 1.5% of total world electricity consumption and is expected to continue to increase. With the proportion of energy use in the data center, it covers 52% of electrical energy for information technology (IT) equipment, 38% for cooling and 10% for supporting equipment. One of the problems faced by data centers is the cooling of information technology (IT) components that are relatively large in energy, this has been a separate concern in several years of research. This paper describes cooling models that have the potential to improve the efficiency of using energy data centers. There have been many studies using several methods in order to find the most effective way to transfer heat data centers, one of them using the immersion cooling method. Immersion cooling promises energy efficiency improvements in the data center, using dielectric fluids that have high heat capacity. Several types of fluids and immersion cooling methods are identified and discussed in this paper. Keywords: Electricity Consumption, Cooling Methods, Energy Efficiency, Immersion Cooling PermaLink | Plain Format | Corresponding Author (Ilham Wahyu Kuncoro)

80	Mechanical Engineering	ABS-1105
An Experimental Investigation On The Effects Of Mineral Oil Flow Rate On Cpu Immersion Cooling Samuel Nanda Kristian(a), Kukuh Mukti Wibowo(a), Nugroho Agung Pambudi(a*), Budi Harjanto(a), Husin Bugis(a), Muhammad Kunta Biddinika(b), Ilham Wahyu Kuncoro(a) (a)Mechanical Engineering education, Teacher Training and Education Faculty, Sebelas Maret University, Jl. Ir. Sutami 36A, Jebres, Kota Surakarta 57126, Indonesia *agung.pambudi[at]staff.uns.ac.id (b)School of Environment and SocietyTokyo Institute of Technology Abstract The aim of this research is to analyze the effect of using immersion cooling with different flow rate and fan rotation on decreasing the temperature on CPU. The study used three variables of flow rate: 0.5, 1 and 1.5lpm. in addition, three other variables of fan rotation, 400, 600, and 800 rpm, were used as well.. Data collection was by means of benchmark software to load the CPU to work maximum and the logging software to record the temperature. The results show that the immersion cooling could potentially be utilized as the new and more effective cooling system. The most optimum variable to decrease the temperature was 1, 5 lpm with fan rotation at 800 rpm. It decreased the maximum temperature from 60 °C to 47 °C, a deviation of 13 °C lower compared to the conventional fan cooling system with air as a medium. The study established that the higher the flow rate and the fan rotation, the higher temperature can be decrease. Therefore, immersion cooling can be the solution to decrease the consumption of energy on IT sector on a bigger scale. Keywords: Immersion cooling, mineral oil, flow rate PermaLink | Plain Format | Corresponding Author (kukuh mukti wibowo)

81	Mechanical Engineering	ABS-338
Preliminary study of acidic hydrolysis in third generation bioethanol production using green algae M. Yheni (1), H.C. Theofany (1), H.B. Aditiya (1*), N.S. Sepwin (2) (1)Department of Mechanical Engineering, Sampoerna University, Jl. Raya Pasar Minggu, Kav 16, Jakarta 12780, Indonesia (2) Department of Applied Physics, Sampoerna University, Jl. Raya Pasar Minggu, Kav 16, Jakarta 12780, Indonesia *aditiya.harjon[at]sampoernauniversity.ac.id Abstract In a mission to reduce the world’s dependency on non-renewable energy sources, through decades, researches are striving to find the best alternative energy substitutions. Considering the abundance availability of renewable sources, green algae are discovered as one promising candidate of future energy alternative. The aim of this research is to study the bioethanol production from green algae through acid hydrolysis. In this study, the acid hydrolysis was performed by utilizing sulphuric acid (H2SO4) at concentration range of 1.0M-2.0M. Further, hydrolysis temperature was also varied at 50, 70 and 90°C. In this stage, a fixed hydrolysis period was set for 30 minutes. As acid pretreatment is considered in this study as an effective way to convert carbohydrates into fermentable sugars, the sugars produced in this experiment would lead to an excellent grade of bioethanol produced. From the obtained result, green algae show a feasibly potential as the third generation bioethanol feedstock, which worth for substituting the use of fossil fuel in the near future. Keywords: bioethanol; green algae; acid hydrolysis; PermaLink | Plain Format | Corresponding Author (Yheni Mulyaningsih)

82	Mechanical Engineering	ABS-1106
How vocational high-school students understand geothermal energy Wahyudi(a), Nugroho Agung Pambudi(a*), Muhammad Kunta Biddinika(b), and Basori(a) (a) Mechanical Engineering Education, Universitas Sebelas Maret, Jl. Ir. Sutami No. 36A, Surakarta, Indonesia *agung.pambudi[at]staff.uns.ac.id (b) School of Environment and Society, Tokyo Institute of Technology, 2 Chome-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan Abstract Indonesia has the highest potential of geothermal energy in the world with 30 GW. However, the utilization ratio is low with around 5% only. This situation occur since there are several geothermal energy targets failed to be achieved. The development of geothermal energy have several problems and one of them is rejection in the community when geothermal development begins. To overcome this situation, an increase in community understanding of this technology usage needs to be conducted. Therefore, the objective of this study is to discover public understanding by exploring the knowledge of vocational high school students about geothermal energy. This is conducted because they are young people who are part of the community. Their knowledge plays an important role in selecting energy sources for the country in the future. This study uses a triangulation strategy model that combines quantitative and qualitative methods. Respondents were students in Indonesia with a case study in Karanganyar Regency, Central of Java. Knowledge is measured by an indicator of the level of understanding of geothermal technology. Keywords: Geothermal Energy, Energy Policy, Knowledge, Vocational High School PermaLink | Plain Format | Corresponding Author (Wahyudi )

83	Mechanical Engineering	ABS-1108
COMPARISON OF PERFORMANCE R-22, R-32, R-290, R-1270 ON AC RESIDENTIAL UNITS WITH HOT LOAD VARIATION Kamin Sumardi Mechanical Engineering Education Department, FPTK Universitas Pendidikan Indonesia Abstract This study is to compare the performance of synthetic refrigerants with hydrocarbons with variations in heat in residential AC units. The test method used is an experiment. Testing using split AC residential 1 HP. Paramter is tested, namely: effective energy ratio (EER), coefficient of performance (CoP), refrigeration effect (RE), amount of refrigerant flowing, pressure, temperature, and electricity consumption. The results showed that in general the performance of R-1270 is better than synthetic refrigerants. The EER, CoP, and RE R-1270 are greater than synthetic refrigerants. This value indicates that the R-1270 has a greater performance. The amount of refrigerant flowing, pressure, and energy consumption of electricity R-1270 are smaller than synthetic refrigerants. The data shows that R-1270 is more efficient than synthetic refrigerants. The lowest temperature that can be achieved by R-1270 is 1-2 oC higher than synthetic refrigerant. The difference does not have a big effect on the room to be conditioned. Comparison of performance with R-290 hydrocarbon refrigerants, R-1270 performance is still slightly below the performance of R-290. The difference is because the material used by the two hydrocarbons is different. The conclusion of this study is that R-1270 and R-290 are more effective and efficient for use in residential air conditioners. Technically R-1270 and R-290 can replace (retrofit) R-22 and R-32 in residential AC systems. Keywords: Hidrocarbon refrigerant, Residential air conditioning PermaLink | Plain Format | Corresponding Author (Kamin Sumardi)

84	Mechanical Engineering	ABS-1109
Readability of Geothermal Energy Information in Vocational Textbooks Windah Yuniar (a), Nugroho Agung Pambudi (a*), Muhammad Kunta Biddinika (b), Ranto(a) a) Mechanical Engineering Education, Universitas Sebelas Maret, Jl. Ir. Sutami No. 36A, Surakarta, Indonesia *agung.pambudi[at]staff.uns.ac.id b) School of Environment and Society, Tokyo Institute of Technology, 2 Chome-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan Abstract The development of renewable energy in a country is influenced by public understanding by its people and this understanding is influenced by public literacy. To improve this, effort is needed to increase the level public literacy by improving readability. We study the readability of geothermal energy in vocational high school textbooks written in Indonesian. This is conducted because it is considered to have an effect on the low utilization ratio in the country. This readability research uses survey methods with population is student in vocational high school. Text material is read by the respondent and they are asked to give the impression whether the text is easy or difficult to understand. From this study, the factors that influence the ability to understand text information are displayed. The purpose of this study is to improve geothermal energy literacy, there for the application and development of this energy increase in the future. Keywords: Readability; Textbooks; Geothermal Energy; Renewable Energy; Vocational Schools PermaLink | Plain Format | Corresponding Author (Windah Yuniar)

85	Mechanical Engineering	ABS-1110
Barriers to the adoption of electric vehicles (EV), acceptance surveys and public perceptions in Indonesia: case studies in the city of Surakarta Febrio Hani Syamnur (a), Nugroho Agung Pambudi (a*), Muhammad Kunta Biddinika (b), and Nyenyep Sri Wardani (a) a) Mechanical Engineering Education, Sebelas Maret University, Jl. Ir. Sutami No. 36A, Surakarta, Indonesia *agung.pambudi[at]staff.uns.ac.id b)School of Environment and Society, Tokyo Institute of Technology, 2 Chome-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan Abstract Electric Vehicle (EV) is one of the technologies in the transportation sector that can reduce the amount of emissions. However, EV still faces some difficulties in terms of implementation. its application in several countries is still far from competing with Internal Combustion Engine (ICE) vehicles. Public acceptance of EV is considered as one of the obstacles. Therefore, this study will examine public perceptions of price, performance, and infrastructure and acceptance of this technology. Furthermore, an incentive policy that can be applied is also offered to respondents. The survey method with a quantitative approach is carried out in Indonesia with a population of Surakarta City residents. The results of this study can contribute as a reference for policy makers in drafting energy and transportation policies and as a discussion material for EV companies in their development. Keywords: Electric Vehicles, public acceptance, public perception, transportation, energy policy PermaLink | Plain Format | Corresponding Author (Febrio Hani Syamnur)

86	Mechanical Engineering	ABS-1111
The Attitude Of Local Government Officers Toward Renewable Energy in Indonesia Intan Diastri Pujaningrum (a), Nugroho Agung Pambudi (a*), Muhammad Kunta Biddinika (b), Herman Saputro (a) a) Mechanical Engineering Education, Universitas Sebelas Maret, Jl. Ir. Sutami No. 36A, Surakarta, Indonesia *agung.pambudi[at]staff.uns.ac.id b) School of Environment and Society, Tokyo Institute of Technology, 2 Chome-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan Abstract One of the causes of climate change is the use of fossil fuels. therefore, this triggers efforts to use renewable energy as a substitute fuel. According to REN21 data The development of renewable energy has declined from 2011-2016 along with the worlds energy needs. This issue is triggered, one of which is the policymaking of budget policies from several countries in the world, including in Indonesia. In this context, policy and government are the main components of implementing renewable energy. Therefore, the governments attitude towards renewable energy plays an important role in the success of developing renewable energy. We conducted a survey to explore the attitude of the local government to the potential of renewable energy in Indonesia which has the potential to vary from each region. One area may have more renewable energy potential than the other. The results of this quantitative study are expected to help national policies on the development of renewable energy not only in Indonesia, but also in other countries where the diversity of opportunities spread throughout the region. Keywords: renewable-energy, government officers, politics, policy, attitudes PermaLink | Plain Format | Corresponding Author (Intan Diastri Pujaningrum)

87	Mechanical Engineering	ABS-1113
Public Knowledge in Changes of Fossil Fuel Become Biofuel on the Transportation Sector Rinna Untari (a), Nugroho Agung Pambudi (a*), Muhammad Kunta Biddinika (b), and Budi Harjanto (a) (a) Mechanical Engineering Education, Universitas Sebelas Maret, Jl. Ir. Sutami No. 36A, Surakarta, Indonesia *agung.pambudi[at]staff.uns.ac.id (b) School of Environment and Society, Tokyo Institute of Technology, 2 Chome-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan Abstract The Government of Indonesia through Vision Energy 25/25 saves energy by saving fossil fuels. One sector that consume the largest fossil fuel is transportation. Through the vision, this sector has a great opportunity to make savings by converting fossil fuels into biofuels as stipulated in the mandatory B20 policy. The success of the implementation of the policies depends on providing socialization to the public. Therefore, the objective of this study is to collect the information about the level of knowledge of the community in receiving information about the use of biofuels in the transportation sector. This is a quantitative study using a questionnaire in data collection, finding that peoples understanding of biofuels, including the perception and information of biofuels, still needs to be improved. The results of the research can be used to assist in the planning, implementation and evaluation of policies made in the use of biofuels in the transportation sector in Indonesia. Keywords: biofuel, fossil fuel, public knowladge, transportation, energy policy PermaLink | Plain Format | Corresponding Author (Rinna Untari)

88	Mechanical Engineering	ABS-1114
Organic Rankine Cycle (ORC) in geothermal power plants Miftah Hijriawan (a), Nugroho Agung Pambudi (a*), Muhammad Kunta Biddinika (b), Danar Susilo Wijayanto (a), Ilham Wahyu Kuncoro (a), Bayu Rudiyanto (c) a) Teacher Training and Education Faculty, Sebelas Maret University Jalan Ir. Sutami No.36 A, Surakarta 57126, Indonesia *agung.pambudi[at]staff.uns.ac.id b) School of Environment and Society, Tokyo Institute of Technology 2-12-1 Okayama, Tokyo 152-8550, Japan c) Renewable Energy Department, Politeknik Negeri Jember Lingkungan Panji, Jember 68124, Indonesia Abstract Organic Rankine Cycle is a technology that convert low-temperature heat sources into a mechanical energy, and it can be used to produce electrical energy in a closed system. The heat sources can be received from renewable energy such as geothermal, solar, and biomass. Furthermore, the ORC system can also be used to increase energy efficiency in the industry by utilizing the waste heat produced. Therefore, there are two classification of the ORC system namely a heat recovery system and binary power plant. Recently, the ORC system has made a thrive in the geothermal power plant. The ORC system can be applied to resources with low to medium temperature characteristics (<90°C - 150°C). This paper will present an overview of the implementation, model, and innovation of ORC system technology in geothermal resources. Keywords: ORC, geothermal, heat recovery system, binary power plant PermaLink | Plain Format | Corresponding Author (Miftah Hijriawan)

89	Mechanical Engineering	ABS-615
Effect of heating time of silica gel extraction from rice husk ash toward fire propagation rate for paper coating Himawan Hadi Sutrisno Riza Wirawan Andralisa Febriyani Desi Ambarwati Universitas Negeri Jakarta Abstract Silica is one of chemical elements, which contains a high thermal characteristic compared to other substances. Therefore, this element is frequently utilized as an additional element that can withstand fire propagation rate by providing heating variation in silica production such as 15 minutes, 30 minutes, 45 minutes and one hour of heating time. It gives an impact toward the thermal characteristic from the production process of the silica gel with KOH solvent. The thermal characteristic is tested by using a thermogravimetric analysis. Meanwhile, in order to discover a decrease of the fire propagation rate, a test is conducted with flammability test with paper medium coated by the silica gel. From TGA result, in 300°C temperature, the silica gel heated in the equipment does not experience many changes of mass, although when the temperature is increased to 600°C, there is still a relatively high residual material compared to the initial mass. The test result using TGA and flammability test shows that the silica gel extracted from the rice husk ash by using KOH solvent with 15 minutes of heating time contains a good thermal characteristic compared to other variants. Meanwhile, a sample of paper, which has been soaked with 15 minutes of time variant produces more residuals compared to other samples Keywords: Silica, Rice Husk Ash, Thermal PermaLink | Plain Format | Corresponding Author (himawan hadi sutrisno)

90	Mechanical Engineering	ABS-618
The Influence of Acid and Base Solutions on the QUENCHING Process Against the Hardness of ST37 Steel Ali Akbar(1*), Rachmat Firdaus(2), Mulyadi(3) (1,2,3) Mechanical Engineering, Universitas Muhammadiyah Sidoarjo, Indonesia Abstract Previous research stated that salt water cooling media has higher hardness value after going through the heat treatment process compared to freshwater cooling media. From this explanation, a study was conducted on the effect of using acid and alkaline solutions in the quenching process against the hardness of ST37 steel. This study uses vinegar water cooling media and soapy water. In this study several steps were carried out, namely: hardening on ST37 steel with a heating temperature of 700ºC with a holding time of 15 minutes, direct quenching with acidic cooling media (vinegar: 2.4 pH) and alkaline solution (soap water: 9.3 pH ) with a 15 minute holding time. After the heat treatment process and direct quenching on ST37 steel, Rockwell hardness was tested. From the test results, the use of acid and base solution cooling media in the quenching process has an effect on the hardness of ST37 steel, the best hardness value is an alkaline solution compared to an acid solution, alkaline solution has a hard value of 66.73 HRC, while acid solution has a hardness value of 64.31 HRC . Keywords: ST37 steel, acid solution, alkaline solution, quenching, hardness. PermaLink | Plain Format | Corresponding Author (ALI AKBAR)

Page 3 (data 61 to 90 of 1039) | Displayed ini 30 data/page
<< PREV 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 NEXT >>

Powered By Konfrenzi 1.832K-Build4 © 2025 All Rights Reserved