Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

IPTEK The Journal for Technology and Science

jts
Website

Published by Institut Teknologi Sepuluh Nopember Surabaya

ISSN : 08534098 EISSN : 20882033 DOI : -

Core Subject : Science,

Computer Science & IT

IPTEK The Journal for Technology and Science (eISSN: 2088-2033; Print ISSN:0853-4098), is an academic journal on the issued related to natural science and technology. The journal initially published four issues every year, i.e. February, May, August, and November. From 2014, IPTEK the Journal for Technology and Science publish three times a year, they are in April, August and December in online version.

Arjuna Subject : -

Articles 11 Documents

1 2

Search results for , issue "Vol 30, No 2 (2019)" : 11 Documents clear

Effect of Increasing Sea Water Temperature on Performance of Steam Turbine of Muara Tawar Power Plant Nastopo Darmawan; Triyogi Yuwono
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Muara Tawar Power Plant is located on the coast of Bekasi, West Java, Indonesia. Along with the economic development, there are plans to do reclamation the sea around Muara Tawar Power Plant and build around it as a port and industrial estate. This could potentially lead to an increase in sea water temperatures. This paper aims to determine the effect of increasing sea water temperature on the performance of steam turbine 1.4 in Muara Tawar Power Plant, which uses sea water as a condenser cooling medium. The intended performance is the output power of the steam turbine, the condenser pressure and the system efficiency. Steam turbine 1.4 has 225 MW installed output power, supplied from 3 HRSG (Heat Recovery Steam Generator).Analysis of the effect of sea water temperature rise on steam turbine performance is carried out by using the cycle-tempo software. The main equipment of steam turbine is modeled in cycle-tempo, then model is validated by comparing with design data. Varies sea water temperature then is inputted on model in order to obtain the output power of steam turbine, condenser pressure and system efficiency. The results show that for every 1˚C increase in condenser cooling water temperature extracted from seawater near the plant, the output power of the plant decreased by about 0.171%, the condenser pressure increased by about 5.146%, and the system efficiency decreased by about 0.168%.

Coulomb Stress Analysis of Halmahera Earthquake on June 7th 2016, Mw=6.3 and Its Correlation with Aftershocks Fathony Akbar Pratikno; Gazali Rachman; Bagus Jaya Santosa
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Main earthquake with magnitude Mw 6.3, has been occurred in the West of Halmahera Island, Northern Molucca on June 7th, 2016. The activity of the Pacific plate, Eurasia plate and Indo-Australia plates trigger some earthquake around Halmahera. The purpose of the current study was to determine the Coulomb stress change of the main earthquake and predict the aftershocks’ location around it. For understanding an interaction of the faults, this study used Coulomb stress change model. Three component seismic waveform data recorded by TNTI station within 132 km, SANI station within 381.2 km, LUWI station within 478.3 km, and TOLI2 station within 617.6 km of the epicenter. This study used software ISOLA-GUI to obtain the parameters of the earthquake source. The parameters of the earthquake source were then used to determine fracture orientation, length, width and slip displacement. It was also used to calculate the Coulomb stress changes around the main shock, using software Coulomb 33. The result shows that the orientation of the earthquake fault has a dip angle of 48° to the horizontal plane and has a strike of 210° against the North. The fault length is 19.49 km, the fault width is 11.59 km and slip displacement is 49.43 cm. Based on plotting result, the main earthquake in Northern Molucca on June 7th, 2016 has positive Coulomb stress change that spread across the Northeast to the Southwest. This change is likely triggered three aftershocks with a range of Mw 4.7 to 6.2.

Performance Study of Installed an I-65o Type Cylinder at The Upstream of Returning Blade of Savonius Wind Turbine, Comparison With Conventional Savonius Wind Turbine Gunawan Sakti; Triyogi Yuwono
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Savonius wind turbine has many advantages over others in that its constructions are simpler and cheaper; it is independent of the wind direction and has a good starting torque at lower wind speeds. However, this type of wind turbine has the lowest performance compared to others types of wind turbine. That is why various studies have been done to improve the performance of the turbine Savonius. This paper is proposed in order to increasing the performance of Savonius wind turbine experimentally by installing an I-65o type bluff body at the upstream of returning blade of the turbine. The experiments are carried out for free stream velocity (U) of 7 m/s corresponds to Reynolds number of about 127.000 (based on the characteristic length of d = 2D-e and free stream velocity (U) from fan used. The center to center distance between the I-65o type cylinder and the returning blade turbine relative to turbine blade diameter S/D specified for 1.4. The diameter of I-65o type cylinder relative to turbine blade diameter is 0.5. The result of experimental show that in general compared to conventional Savonius wind turbines, the placement of I-65o type cylinder in front of the returning blade of the Savonius wind turbine is effective for improving turbine performance. The results of this experiment show that for Re = 127,000, the power coefficient of the turbine with the I-65o type cylinder is greater than when the turbine has no I-65o type cylinder or conventional Savonius wind turbine. Where in this condition, the maximum coefficient of power the Savonius turbine (CP) with I-65o type cylinder can actually increase to 25.66 % compared to the turbine without the I-65o type cylinder; this is obtained for Tip Speed Ratio of 0.76.

The Experimental Study of The Effect of Air Preheating in MSW Pellet Multi-Stage Downdraft Gasifier Depi Rustam Ependi; Arif Rahman Saleh; Bambang Sudarmanta
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

High municipal solid waste generation in Indonesia can be used to substitute fossil energy. MSW is converted into pellet form to uniform moisture content. This study aimed to improve the performance of gasified downdraft gasifier processes by heating air inlets in pyrolysis, oxidation, and reduction zones. Variations of air temperature inlet in these zones are 80 oC, 110 oC, 150 oC, and 210oC. The results of this study obtained the highest air temperature at 210 ºC for 969 ºC. The syn-gas compositions (CO and H2) at an increase in temperature of 80-210 ºC increased from 21.4%, 9.99%, and 1.77% to 22.79%, 10.28%, and 1, 79% respectively. Cold gas efficiency increased by 5.13 % and the lowest tar level was 34.39 mg/Nm3. Based on the result of research, preheated air can improve the efficiency of gasification and reduce tar content in the syngas.

3-D Numerical Study of CFB 110 MW: Fluidization in Furnace and Cyclone with Loads And Air Combustion Variation Ari Wirahadi; Heru Mirmanto
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Circulating Fluidized Bed (CFB) Boiler has advantages when uses low rank coal compared to Pulverized Boiler. It will be less operational cost but it has greater risk in degradation because of sands material inside the process. Air combustion between primary air and secondary air is one importance parameter that influence fluidization of CFB. Numerical simulation of commercial CFD was used with Eulerian multiphase model implemented to analyzed sand volume of fraction, air and sand velocity including distribution of pressure around furnace. It was used 55%-45% air combustion ratio of primary and secondary air as reference when boiler operated at 63% and 100% based on operation performance of CFB and then it was simulated with additional variation of air combustion ratio with 50%-50%. Simulation of 110% load was added using all of variation of air combustion. The simulation showed that fluidization with air combustion ratio 50%-50% and 55%-45% executed well when operated at 63%. Meanwhile, fluidization 100% and 110% with all those air combustion ratios would cause a great number of sands entered inlet cyclone and higher sands and air velocities.

Improvement of Preventive Maintenance Process Effectiveness in Insourcing and Outsourcing Scheme with House of Risk (HOR) Method Approach (A Case Study) Budi Siswanto; Adithya Sudiarno; Putu Dana Karningsih; Henry Pariaman
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Outsourcing has become the alternative scheme to gain improvement in several fields within a short time to many enterprises. One power generation in North Java implemented PM as planned maintenance strategy to maintain equipment by conducting insourcing and outsourcing scheme as PM execution. Both conditions must follow the same business process flow in PM execution process and there will occur some obstacles that interrupted PM process. The existing problem will be analyzed with House of Risk (HOR) method approach, supported by Integrated Manufacturing Open Systems Architecture (CIMOSA) process-based function modeling for identification method and Supply Chain Risk Identification System (SCRIS) risk structure identification used for mapping problem, root cause, and its relation. Analysis with HOR results in root causes that occurred within PM implementation process for both of them commonly has the same problem that is process business acknowledgment, but in outsourcing scheme not exist root cause on culture compliance and work task requirement, because they have a descriptive target to obtain service level agreement fulfillment. On both scheme still need an improving method to monitor and evaluate the PM work for better performance.

Effect of Halide Concentration on the Effectiveness of Banana Peel Waste Inhibitor at 60C Widodo, Mochamad Puji; Tua Silaen, Yohannes Marudut; Ahada Kuswara, Muhammad Faiq Ridho; Rohmannudin, Tubagus Noor
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Organic inhibitors have been widely studying to be an alternative corrosion prevention because of its abundance and non-hazardous effect to the environment. One of organic inhibitors which is obtained from plant extract is banana (Musa Paradisica) peel, because it has gallocatechin which is a strong antioxidant. Otherwise, inhibition effectiveness from organic compound decreases during increasing of temperature. However, the addition of other substance like halide ion has provided multiple effect of corrosion inhibitor effectiveness. The addition of the halide ions can enhanced the inhibition efficiency of the organic inhibitors. This research highlights the effect of additional halide concentration to the inhibition effectiveness of Musa Paradisica (banana) peel on API 5 L steel in 3,5% NaCl at temperature 600C. This inhibition performance is investigated using weight loss measurement and electrochemical measurement. Result shows that the maximum inhibition efficiency was observed with the mixture of 500 ppm banana peel waaste extract and 100 ppm potassium iodide at 600C. Also, The blends behaved as mixed type inhibitor. The effectiveness was found to be in order of KI > KBr due to the larger ionic radius in iodide ion.

Siamese Long Short-Term Memory for Detecting Conflict of Interest on Scientific Papers Ilmi, Akhmad Bakhrul; Purwitasari, Diana; Fatichah, Chastine
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Scientific articles cited by other researchers have an impact on increasing author credibility. However, the citation process may be misused to unnaturally raise a bibliometric indicator value such as researcherâ€™s h-index. Researchers may overly cites their own works, referred as self-citation, even though the topic of the references are not related to the current article. Further misconduct is excessive citations on the works of peoples related to the researcher which can be coercive or not, referred as conflict of interest (CoI). The proposed method uses a deep learning approach, Siamese Long ShortTerm Memory (LSTM), to recognize subject similarities between a scientific article and its references. Standard text similarity fails to do so because contextual relatedness of sentences in the articles need some learning process. Siamese-LSTM learns contextual relatedness of sentences in the article using two identical LSTM. Steps of the proposed method are (i) word-embedding to get weight values of terms but still considers their semantic relations, (ii) k-means clustering to generate training data for reducing time complexity in Siamese-LSTM learning of scientific articles, (iii) learns Siamese-LSTM weight from training data to identify contextual relatedness of sentences, (iv) calculate similarity of a scientific article with its references based on Siamese-LSTM. The empirical experiments are used to analyze similarity values and the possibility for conflict of interest in an article.

The Effect of Water Contents to Diesel Fuel-Water Emulsion Fuel Stability Suryadi, Joko; Winardi, Sugeng; Nurtono, Tantular
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

The declining world oil and gas reserves along with increasing gas emissions from fossil fuel consumption has received serious attention as an urgent problem worldwide. The alternative solution to the problem uses emulsified fuel which is expected to provide better combustion efficiency and will contribute to emission reductions, such as NOx and particulate matter (PM). The one of most important factor in emulsion fuel is its stability. In this work, the effect of water contents to stability of diesel-water emulsion fuels has been investigated. The stability of emulsion fuel related to coalescence and sedimentation formation. The diesel fuel-water emulsification process was carried out in a standard stirred tank consisting of a cylinder tank (93 mm in diameter) and Rushton disk turbine (40 mm in diameter). Materials used consist of diesel oil (Pertamina DEX), demineralized water, surfactants (Lecithin, Triton X-100 and Tween 80). The surfactant used is a mixture of Lecithin - Triton X-100 (76.6%: 23.4%) and Lecithin - Tween 80 (45.5%: 54.5%) at 1% total volume of emulsion. The impeller set in constant speed at 1900 rpm. To reduce emulsification energy consumption, water is added gradually into the tank at 2 mL/min of flowrate. Water content varies at 5%, 10%, 20%, and 40% by total volume of emulsion. Physical properties of emulsion fuel such as viscosity and density at room temperature were investigated periodically. The characterization of emulsion fuel stability was measured by slope value of absorbance ratio at wavelength 450 nm and 850 nm. Sediment formation was periodically by visual observation as emulsion phase percentage. Emulsion droplet size was measured by Dynamic Light Scattering (DLS) method. Physical properties of emulsions such as density and viscosity tend to constant value in order of time. Emulsion fuel with 5% water content has the largest volume of emulsion phase in the rest of time, 83 % for L-T emulsion fuel and 95% for L-Tx. The lowest slope value shown by 5% emulsion fuel water content, -8.657Ã—10-5 for 5% L-T emulsion fuel and -2,084 Ã— 10-4 for 5% L-Tx emulsion fuel. Droplet size measurement of emulsion shown that different amount of added water caused the different droplet size of emulsion.

The Effects CNG Injection Timing on Engine Performance and Emissions Of A Diesel Dual Fuel Engine Moch. Aziz Kurniawan; Dori Yuvenda; Bambang Sudarmanta
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Sequential combustion process on diesel dual fuel engine with compressed natural gas (CNG) fuel was complex. The problems of diesel dual fuel with CNG gas are reduced thermal efficiency and resulting in high carbon monoxide (CO) and unburned hydrocarbon (HC) emissions. The right setting between combustion air, diesel pilot fuel, and CNG gas fuel can improvement the performance and emissions. The experiment was conducted with diesel fuel conventional and dual fuel mode with CNG fuel in a single cylinder, four strokes, constant speed (1500 rpm) diesel engine type diamond DI 800. Performance parameters such as thermal efficiency and specific fuel consumption (SFC), emissions such as CO, HC, and smoke density are determined at five starts of injection timing (SOI) CNG of 700CA, 900CA, 1100CA, 1300CA, dan 1500CA ATDC with ECU programmable of Vemstune software. The results indicated that retarded CNG injection timings improved engine performance and emissions diesel dual fuel. Start of CNG injection timing optimization at 1300CA ATDC with increased thermal efficiency 14,35% and decreased specific fuel consumption (SFC) 8,83 % . in addition, it decreased CO emissions 21,35%, HC emissions 17,93%, and PM emissions lower 34,98%. However, engine performance diesel dual fuel lower than a conventional diesel engine.

Page 1 of 2 | Total Record : 11

1 2

Filter by Year

2019 2019

Filter By Issues

All Issue Vol 36, No 1 (2025) Vol 35, No 3 (2024) Vol 35, No 2 (2024) Vol 35, No 1 (2024) Vol 34, No 3 (2023) Vol 34, No 2 (2023) Vol 34, No 1 (2023) Vol 33, No 3 (2022) Vol 33, No 2 (2022) Vol 33, No 1 (2022) Vol 32, No 3 (2021) Vol 32, No 2 (2021) Vol 32, No 1 (2021) Vol 31, No 3 (2020): In-Press Vol 31, No 3 (2020) Vol 31, No 2 (2020) Vol 31, No 1 (2020) Vol 30, No 3 (2019) Vol 30, No 2 (2019) Vol 30, No 1 (2019) Vol 29, No 3 (2018) Vol 29, No 2 (2018) Vol 29, No 1 (2018) Vol 28, No 3 (2017) Vol 28, No 2 (2017) Vol 28, No 1 (2017) Vol 27, No 3 (2016) Vol 27, No 2 (2016) Vol 27, No 1 (2016) Vol 26, No 2 (2015) Vol 26, No 1 (2015) Vol 25, No 3 (2014) Vol 25, No 2 (2014) Vol 25, No 1 (2014) Vol 24, No 3 (2013) Vol 24, No 2 (2013) Vol 24, No 1 (2013) Vol 23, No 4 (2012) Vol 23, No 3 (2012) Vol 23, No 2 (2012) Vol 23, No 1 (2012) Vol 22, No 4 (2011) Vol 22, No 3 (2011) Vol 22, No 2 (2011) Vol 22, No 1 (2011) Vol 21, No 4 (2010) Vol 21, No 3 (2010) Vol 21, No 2 (2010) Vol 21, No 1 (2010) Vol 20, No 4 (2009) Vol 20, No 3 (2009) Vol 20, No 2 (2009) Vol 20, No 1 (2009) Vol 19, No 4 (2008) Vol 19, No 3 (2008) Vol 19, No 2 (2008) Vol 19, No 1 (2008) Vol 18, No 4 (2007) Vol 18, No 3 (2007) Vol 18, No 2 (2007) Vol 18, No 1 (2007) More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota surabaya,

Jawa timur

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kota surabaya, Jawa timur INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota surabaya,

Jawa timur

INDONESIA