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IPTEK The Journal for Technology and Science
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 345 Documents
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Application of Laminated Veneer Lumber (LVL) on the Wooden Boat Construction Ahmad Basuki Widodo
IPTEK The Journal for Technology and Science Vol 23, No 1 (2012)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v23i1.14

Abstract

LVL (Laminated-Veneer Lumber) has many advantages and economic values, which is important for wooden boat construction. The recovery of veneer, the main material of LVL, are higher than sawn-timber and their drying process are faster. LVL produced with a continuous press has been approved as an engineered material with reliable strength and stiffness. In a wooden boat processing, the easy forming into a curve shape and strength are main factor, because of the streamline shape of boats. LVL material is able to meet those requirements. As an endless-length LVL is made from a log limited-length hence LVL always contain joints. Butt joint have numerous drawbacks, but they are inherently simple and less time to manufacture than other joints types. The purposes of this experiment are to investigate the basic characteristics of LVL which are important for deck and hull planking in the wooden boat constructions. Yellow meranti and red meranti were peeled by a veneer lathe and phenol formaldehyde adhesive were used. Result of experiment indicated that at the position 0o (β), the flexibility and strength of LVL up to proportional limit increased with increasing number of layer and spacing of butt-joint (d/t). LVL at the position 45o and 90o (β), all types of LVL had lower flexibility and strength than the standard value for deck and hull planking. In bending experiment test speciment at position 45° with direction of grain, maximum width of LVL equal to the spacing of frame and at position 90° equal to the width of hull planking in wooden boat. Based on the interpretations of the above results, it can be concluded that (1). LVL of 9, 6 and 4 plies with upside (inside) veneer butt-joint is appropriate for deck and hull planking in wooden boat manufacturing, (2). LVL of 9, 6 and 4 plies with spacing of butt-joint (d/t) more than 20 is appropriate for deck and hull planking in manufacturing wooden boat.
The Effect of Substrate Types to FAME Conversion on Acid-Catalyzed Transesterification of Crude Rice Bran Oil Orchidea Rahmaniah
IPTEK The Journal for Technology and Science Vol 18, No 3 (2007)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v18i3.169

Abstract

Biodiesel is an alkyl ester which is made from vegetable oils or animal fats. Indonesian biodiesel development is an urgent condition. The abundance of Indonesia’s natural sources is not manage well until now, such as rice bran. Rice bran oil is considered to be one of the most nutritious oils due to its favorable fatty acid composition and an unique combination of naturally occurring biologically active and antioxidant compounds. Acid catalyzed are the most suitable methods to produce biodiesel from high fatty acid rice bran oil. This present study was carried out to investigate the effects of substrate types from pure crude rice bran oil compounds on fatty acid methyl ester (FAME) formation. Experimental results shows, reaction rate of fatty acid to FAME was faster compare to triglyceride, incorporated 5%-H2O to pure triglyceride substrat didn’t increase the reaction rate. Rice bran oil high fatty acid content (15-70% FA) reached 85-98% conversion of FAME within 1 hour reaction, while oil with low fatty acid content (3-10% FA) only gives 25-75% conversion. The chain lengths, double bond, degree of saturation and chemical structure of fatty acid did not influence rate reaction of transesterification Fatty acids from different sources shows similar conversions and change in the fatty acids composition has no effect on rate of methanolysis.
Optimization of Palmitic Acid Composition in Crude Oleic Acid to Provide Specifications of Titer and Cloud Point of Distillate Oleic Acid using a Flash Distiller Muhammad Yusuf Ritonga
IPTEK The Journal for Technology and Science Vol 21, No 4 (2010)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v21i4.48

Abstract

Titer and cloud point of Distilled Oleic Acid is higher than is the standard on feed composition palmitic acid (C15H31COOH) or C16 11.2 %. Feed composition C16, top temperature precut and bottom main distiller column were optimized to produce DOA. A factorial design with 3 independent variables, 3 X 2 X 3, repeated twice as much, is applied to observe effects of feed composition C16 to quality parameters. In the optimum C16, feed composition at 5.20 % produced DOA with titer 6.8 oC, cloud point 5.0 oC (inside its specification).
Assessment of Displacement Flow at Ketandan Creeks to Optimizing Land Use in Jember New City Housing Entin Hidayah; Wiwik Yunarni Widiarti; Anik Ratnaningsih
IPTEK The Journal for Technology and Science Vol 26, No 1 (2015)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v26i1.1017

Abstract

Displacement flow will caused a change in the flow characteristics such as flow depth, discharge, river slope and width of the river surface. If not carefully examined, it will cause the riverbed erosion, sedimentation and risk of flooding. This paper aims to assess the hydrology and hydraulics of the river flow changes in Ketandan creek in optimizing the use of land housing for Jember New City (JNC). Hydrology modelling studies conducted for the return period rainfall include a 2 year as normal discharge, and 100 year as flood condition. Simulation of flood designs used to assess changes in the flow regime in the channel and the risk of flooding with HEC-RAS program. The results of the study showed that for the flood design 3,1 m3/sec and 12,8 m3/sec will give the effect of critical water surface. In order to keep the flow of the river bed of critically needed as the drop-structure and spillway construction
Engine Torque Control of SI Engine using Linear Quadratic Integral Tracking (LQIT) Optimal Control Aris Triwiyatno; Mohammad Nuh; Ari Santoso; I Nyoman Sutantra
IPTEK The Journal for Technology and Science Vol 22, No 4 (2011)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v22i4.80

Abstract

Due to the needs of improving fuel economy and reducing emissions, it is increasingly important to achieve control over robustness behavior and meet performance objectives over the life of the vehicle. This requires the development of high performance and optimal power train controllers. The performance objectives are often conflicting, or at least interrelated. One way to potentially meet these performance requirements is to introduce a method of controlling engine torque of Spark Ignition (SI) engine using Linear Quadratic Integral Tracking (LQIT) optimal control. The goal is to develop simple algorithms which can control engine torque well, thus providing fuel control more efficient and simultaneously improving engine performance due to the needs of the driver based on throttle opening information. In this case, spark ignition engine with automatic transmission simulation model is used to meet a good performance under this controller design.
Effect of Hydrothermal Extraction Condition on The Content of Phenolic Compound Extracted from Rind of Mangosteen (Garcinia mangostana) and Its Antioxidant Efficiency Ash Shiddiqi, Qifni Yasa; Karisma, Achmad Dwitama; Machmudah, Siti; Widiyastuti, Widiyastuti; Nurtono, Tantular; Winardi, Sugeng; Wahyudiono, Wahyudiono; Goto, Motonobu
IPTEK The Journal for Technology and Science Vol 25, No 2 (2014)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v25i2.462

Abstract

Xanthone is an antioxidant compound contained in the rind of mangosteen. There are some methods to extract Xanthone from rind of mangosteen, and one of them is hydrothermal extraction. Hydrothermal extraction is a method to obtain xanthone from rind of mangosteen using water at teIn this work, the effect of extraction temperature, pressure, and mode (batch and continuous), and particle size of starting material on the yield and recovery of extracted xanthone and phenolic compounds was investigated. Extraction was carried out at various temperatures (120, 150, and 180oC) and pressures (1, 3, and 5 MPa) and constant flow rate of 1 mL/min. The xanthone content and antioxidant efficiency of extract was examined by using spectrophotometer, while the concentration of total phenolic compounds in the extract was determined with folin ciocalteu reagent and examined using spectrophotometer In order to confirm the extracted phenolic compounds, the extract residue was analyzed by using FTIR. The experimental result showed that the increase in pressure and temperature caused an increase in total phenolic compound concentration and yield of xanthone. In addition, the result also showed that antioxidant activities were observed in the extract of mangosteen rind.
Thermal Analysis on Radial Flux Permanent Magnet Generator (PMG) using Finite Element Method Irasari, Pudji; Syaeful A, Hilman Syaeful A; Kasim, Muhammad
IPTEK The Journal for Technology and Science Vol 22, No 2 (2011)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v22i2.59

Abstract

The main source of heat in the permanent magnet generator (PMG) is the total losses which f come from winding losses, core losses and rotational losses. Total heat arising from such these losses must be properly distributed and maintained so as not to exceed the maximum allowable temperature to prevent damage to insulation on the winding and demagnetization on the permanent magnet machines. In this research, we consider thermal analysis which is occurred on the radial flux PMG by using finite element method to determine the extent to which the heat generated can be properly distributed. The simulation results show that there are no points of heat concentration or hot spot. The simulation maximum temperatures of the permanent magnet and the winding are 39.1oC and 72.5oC respectively while the experimental maximum temperature of the winding is 62oC.
Lightning Performance of Extra High Voltage 500 kV Lines at East Java- Indonesia Zoro, Reynaldo; Y. Pramono, Eko
IPTEK The Journal for Technology and Science Vol 19, No 4 (2008)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v19i4.142

Abstract

Extra High Voltage (EHV) 500 kV transmission lines has higher insulation strength against overvoltages produced by lightning strikes compare to lower transmission lines voltage such as 150 kV or 70 kV transmission lines. Observation was carried out at EHV 500 kV Paiton-Kediri line located at east Java island of Indonesia. This line has operated for more than five-years. In fact is there were many insulators were broken by lightning strikes, especially during rainy season. A large number of broken insulator at many towers deterioted performance of the lines, in which many line outages occured. This study presents the evaluation results of performance of the lines concerning its robustness agains lighting strikes. Investigation of the characteristics of lightning strikes in the area along the lines was carried out. From this observation and study it founds that some towers need to be improved to have better performance against overvoltage due to direct lightning strikes to the towers. By using Severity index methodology, local lightning data and innovation technology for lightning protection system significant results were derived.
Sponge Diversity at Pecaron Bay Situbondo Based on Macroscopic and Microscopic Observation Setiawan, Edwin; Nurhayati, Awik Pudji Diah; Muzaki, Farid Kamal
IPTEK The Journal for Technology and Science Vol 20, No 4 (2009)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v20i4.20

Abstract

The sponge species diversity recruited insitu macroscopic observation i.e, underwater photograph for sponges species diversity and spicula microscopic examination for sponges order group specimens have been conducted at Pecaron Bay Situbondo. Seventeen sponges species have been identified out of twenty species. The microscopic examination showed that the Diactinal oxea types were dominant in our 13 samples whereas the monoactinal oxea and style were represented only with 7 samples. Moreover, diactinal type of spicula can be used as an order group of sponges species at Pecaron bay Situbondo.
The Determination of Acoustical Absorbing Materials in The “Al-Marwah” Room of “Al-Akbar” Mosque in Surabaya using Objective Parameters Approximation A. Asmoro, Wiratno
IPTEK The Journal for Technology and Science Vol 18, No 2 (2007)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v18i2.175

Abstract

The room that used to hold the speech activity needs a good acoustical quality. To determine the acoustical quality of a room the experimental research was conducted to find the relationship between the determination of acoustical absorbing materials and speech intelligibility in the “Al-Marwah” room of “Al-Akbar mosque in Surabaya. Through the monaural acoustical measurements, the objective acoustical parameters in the “Al-Marwah” room can be found from impulse responses. Then we can use it to determine the acoustical absorbing materials in the room. Considering the acoustical parameters of RT, EDT, D50, C50, and %Alcons at several positions, we can find the relationships between those parameters. The result, then, could be used to properly judge the acoustical absorbing materials which should be applied in the room. For the acoustical treatments on the ceiling of 376 m2 and the pillars of 373 m2 in the “Al-Marwah” room of the “Al-Akbar” mosque, the average values of RT and EDT un mid-band frequencies were found 5.52 sec and 7.88 sec respectively; whereas the values of D50, C50 and %Alcons were found in the range of 3.25  10.5%, -15  -9,4 dB and 15  21% respectively. Those condition produce speech intelligibility on Poor to Sufficient category.

Page 27 of 35 | Total Record : 345

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