cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kota bandung,
Jawa barat
INDONESIA
Journal of Engineering and Technological Sciences
Published by Institut Teknologi Bandung
ISSN : 23375779     EISSN : 23385502     DOI : -
Core Subject : Engineering,
Engineering
Journal of Engineering and Technological Sciences welcomes full research articles in the area of Engineering Sciences from the following subject areas: Aerospace Engineering, Biotechnology, Chemical Engineering, Civil Engineering, Electrical Engineering, Engineering Physics, Environmental Engineering, Industrial Engineering, Information Engineering, Mechanical Engineering, Material Science and Engineering, Manufacturing Processes, Microelectronics, Mining Engineering, Petroleum Engineering, and other application of physical, biological, chemical and mathematical sciences in engineering. Authors are invited to submit articles that have not been published previously and are not under consideration elsewhere. Starting from Vol. 35, No. 1, 2003, full articles published are available online at http://journal.itb.ac.id, and indexed by Scopus, Index Copernicus, Google Scholar, DOAJ, GetCITED, NewJour, Open J-Gate, The Elektronische Zeitschriftenbibliothek EZB by University Library of Regensburg, EBSCO Open Science Directory, Ei Compendex, Chemical Abstract Service (CAS) and Zurich Open Repository and Archive Journal Database. Publication History Formerly known as: ITB Journal of Engineering Science (2007 – 2012) Proceedings ITB on Engineering Science (2003 - 2007) Proceedings ITB (1961 - 2002)
Arjuna Subject : -
Articles 1,267 Documents
 9   10   11   12   13 
Synthesis of -Al2O3 Catalyst Support from Kaolin of Indonesian Origin Samadhi, Tjokorde Walmiki; Subagjo, Subagjo; Lismana, Kevin R.; Fuadi, Khasin
Journal of Engineering and Technological Sciences Vol 43, No 2 (2011)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (140.925 KB) | DOI: 10.5614/itbj.eng.sci.2011.43.2.3

Abstract

Kaolin  has  been  identified  as  a  potential  raw  material  for  the production of  -Al2O3  for  hydrotreating  catalyst support. This work explores the technical  feasibility  of  applying  the  potassium  hydroxide  (KOH)  e xtraction synthesis route on kaolin  from the Belitung  Island  in Indonesia. The application of  a  published  synthesis  method  to  Belitung  kaolin  requires  an  approximately twofold  increase  in  kaolin  calcination  time,  an  increase  in  kaolin  calcination temperature from 950 to 1000 °C, and a tenfold increase in metakaolin extraction time, to obtain a specific surface area higher than 200 m2/g. The highest specific surface area of 233 m2/g was obtained when  the kaolin was calcined at 1000 °C for 24 hours, and the  metakaolin  was extracted by concentrated KOH  solution for 12 hours.  Phase characterization of the final product confirmed the formation of -Al2O3, but with the inclusion of low-surface area -Al2O3 phase.
A Novel Method for Vector Control of Three-Phase Induction Motor under Open-Phase Fault Jannati, Mohammad; Asgari, Seyed Hesam; Nik Idris, Nik Rumzi; Bin Abdul Aziz, Mohd Junaidi
Journal of Engineering and Technological Sciences Vol 47, No 1 (2015)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (336.592 KB) | DOI: 10.5614/j.eng.technol.sci.2015.47.1.3

Abstract

The majority of electrical machines such as induction motors can be modeled by an equivalent two-phase machine model (d-q model). A three-phase induction motor with  one of the stator phases  opened  (faulty three-phase induction motor) can be also modeled by an equivalent two-phase machine. If a conventional vector control method for balanced three-phase induction motors is used for this faulty machine, significant oscillations in speed and torque will result. In this paper, a novel technique for vector control of faulty three-phase induction motors based on rotor-field oriented control (RFOC) is presented. The performance of the proposed method was evaluated using MATLAB software. The results show that it achieves significant improvements in the oscillation reduction of the speed and torque responses.
The Effect of Ozonation Process on Bromide-Containing Groundwaters in Bandung Area and Its Surroundings Syafila, Mindriany; Sukandar, Sukandar; Haryanto, Eric
Journal of Engineering and Technological Sciences Vol 44, No 3 (2012)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (285.644 KB) | DOI: 10.5614/itbj.eng.sci.2012.44.3.3

Abstract

Disinfection process was applied as the last step of the water treatment to kill pathogenic bacteria in  the  water. However,  according to  several studies, the  ozonation  disinfection  process could form undesired by-products.  One of the by-products  potentially  affecting human life is bromate  produced from bromide ionic-containing  water. This study was carried out to examine the effect of raw water  characteristics  and  pH  on  bromate  formation.  Also,  the  performance  of bromate formation for a period of exposure time was analyzed. Raw waters taken from four different areas around Bandung were exposed to ozone introduced to a reactor with a flow rate of 2 L/min. The pH of the raw waters varied from 4, 7 to 10.  The  results  show  that  there  was  no  evidence  of  an  initial  bromide  ion concentration,  whereas  a  change  in  pH  value  gives  a  significantly  different outcome. In  acidic condition  (pH of 4) the  bromate  formation tends to decrease, whereas  when  the  pH  value  increases  to  a  pH  of  10,  the  bromate  formation increases.  Therefore, for drinking water  with a  neutral pH,  when bromide ions are  detected  in  the  raw  water,  the  drinking  water  may  be  toxic  due  to  the presence of bromate.
Percolation Model for Proton Immobility in Ice Abdullah, Mikrajuddin
Journal of Engineering and Technological Sciences Vol 37, No 1 (2005)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (241.717 KB) | DOI: 10.5614/itbj.eng.sci.2005.37.1.5

Abstract

A simple Ising model and a statistical theory of gel formation in a polymer matrix were combined to explain the effect of temperature on the mobility of protons in ice. Cowin et al observed that protons in ice bulk were immobile at temperatures below 190 K, and suddenly become mobile at temperatures above 190 K [Nature 398, 405 (1999)]. We proposed here that the transport of protons is controlled by a percolation mechanism. The proton transport is facilitated by the occurrence of easily reoriented water molecules in the ice bulk. The fraction of this molecule depends on temperature and was calculated using a simple Ising model. The formation of network of these molecules which provides pathways for proton transport was calculated using a statistical theory of gel formation in a polymeric system. Our model succeeded to reproduce the variation of potential difference between the ice film surfaces with respect to temperature as observed by Cowin et al based on a soft landing experiment.
Utilizing Shear Factor Model and Adding Viscosity Term in Improving a Two-Dimensional Model of Fluid Flow in Non Uniform Porous Media Bindar, Yazid; Makertihartha, IGBN; Supardan, M. Dani; Buchori, Luqman
Journal of Engineering and Technological Sciences Vol 39, No 2 (2007)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (436.337 KB) | DOI: 10.5614/itbj.eng.sci.2007.39.2.3

Abstract

In a packed bed catalytic reactor, the fluid flow phenomena are very complicated because the fluid and solid particle interactions dissipate the energy. The governing equations  were developed in the  forms of  specific  models. The shear factor  model was introduced in the momentum equation for covering the effect  of  flow  and  solid  interactions  in  porous  media.   A  two  dimensional numerical  solution  for  this  kind  of  flow  has  been  constructed  using  the  finite volume  method.  The  porous  media  porosity  was  treated  as  non-uniform distribution  in  the  radial  direction.  Experimentally,  the  axial  velocity  profiles produce  the  trend  of  having  global  maximum  and  minimum  peaks  at  distance very close to the wall. This trend is also accurately picked up by the numerical result. A more comprehensive shear factor formulation results a better velocity prediction than other correlations do. Our derivation on the presence of porous media leads to an additional viscosity term. The effect of this additional viscosity term was investigated numerically. It is found that the additional viscosity term improves  the  velocity  prediction  for  the  case  of  higher  ratio  between  tube  and particle diameters
Nonlinear Finite Element Modeling of Red Meranti Compression at an Angle to the Grain Pranata, Yosafat A.; Suryoatmono, Bambang
Journal of Engineering and Technological Sciences Vol 45, No 3 (2013)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1380.458 KB) | DOI: 10.5614/j.eng.technol.sci.2013.45.3.2

Abstract

In an orthotropic material, the grain angle has a significant influence on its mechanical properties. The aim of this research was to perform a numerical simulation using a nonlinear finite element analysis (FEA) to obtain the compression strength of the Red Meranti (shorea spp.) timber species at an angle to the grain ranging from 12° to 80°. The material properties needed for the analysis were obtained from clear specimen tests. To investigate the validity of the numerical results, various cross grain specimens were tested under uniaxial compressive stress. It has been shown in this study that an FEA based on the distortion energy of an orthotropic material can be used to obtain the compressive strength at proportional limit for cross grain specimens. Compa-rison with the experimental results showed that for a cross grain angle between 12° and 80° the FEA predicted the strength to be 9.4% to 33.6% lower than the experimental results. Compared to using Hankinson’s formula to predict the compressive strength at a cross grain angle, using the FEA always gave a lower value, ranging from 13.2% to 30.5%. Based on these results, an FEA incorporating Hill’s yield criterion is a conservative method for predicting compressive strength at an angle to the grain.
A Two Control Limits Double Sampling Control Chart by Optimizing Producer and Customer Risks Irianto, Dradjad; Juliani, Ani
Journal of Engineering and Technological Sciences Vol 42, No 2 (2010)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (306.72 KB) | DOI: 10.5614/itbj.eng.sci.2010.42.2.5

Abstract

Standard Shewhart process control chart has been widely used, but it is  not  sensitive  in  detecting  small  shift.  A  number  of  alternatives  have  been proposed to improve the  capability  of control chart. The double sampling (DS) control chart is aimed at improving the capability to detect any small shift out-of control  condition  by  observing  the  second  sample  without  interruption.  The capabilities  of DS control chart were measured as the expected sample size (as a measure  of  inspection  cost)  or  the  control  chart  power  (as  a  measure  for customer  risk).  Optimization  of  these  criteria  is  used  to  determine  the  control limits.  In  this  paper,  we  optimize  both  producer  and  customer  risks  under  a certain expected number of sample sizes as the constraint. Comparing the result to  the  previous  procedure  that  only  optimize  customer  risk,  the  proposed optimization  procedure  gives  the  same  first  control  limit  but  smaller  second control limits with higher value of control chart power.
A New Approach to Blending and Loading Problem of Molten Aluminum Li, Jianhua; Xing, Wei
Journal of Engineering and Technological Sciences Vol 46, No 4 (2014)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (166.877 KB) | DOI: 10.5614/j.eng.technol.sci.2014.46.4.8

Abstract

The  problems  of  blending  electrolyzer  and  multi-constraint optimization  of  electrolytic  aluminum  scheduling  in  the  electrolytic  aluminum production process were addressed.  Based on a mathematical model analysis, a novel  hybrid  optimization  algorithm  is  proposed  for  optimization  of  blending together  the  molten aluminum  in different  electrolytic cells. An affinity degree function  was  designed  to  represent  the  path  of  aluminum  scheduling.  The mutation  operators  were  designed  to  implement  the  transformation  of electrolyzer combination and change the route of loading. A typical optimization example from an aluminum plant in northwest China is given in this paper, the results of which demonstrate the effectiveness of the proposed method.
Zinc Oxide Nanoparticles Prepared By a Simple Heating: Effect of Polymer Addition and Polymer Absence on the Morphology Abdullah, Mikrajuddin; Okuyama, Kikuo
Journal of Engineering and Technological Sciences Vol 36, No 2 (2004)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1682.156 KB) | DOI: 10.5614/10.5614/itbj.eng.sci.2004.36.2.5

Abstract

Zinc oxide (ZnO) nanoparticles were prepared by a simple heating of precursors in a furnace at temperatures of below 1000°C in an air environment. If zinc nitrate was used as precursor, polymer (e.g., polyethylene glycol (PEG)) must be added into the precursor to produce ZnO in nanometer size. The absence of polymer led to the presence of several micrometer-sized flakes. In addition, the heating temperatures must be higher than 500°C to completely decompose the organic material in final product. However, if zinc acetate was used as precursor, nanometer-sized ZnO having a high crystallinity can be obtained even when the polymer was absent. Interestingly, we also found that heating at low temperatures (e.g. 400°C) resulted in ZnO nanorods with an elongation ratio of around 5. This method is rapid, economically efficient, and readily scalable for industrial applications.
Development of Wet Noodles Based on Cassava Flour Abidin, Akhmad Z.; Devi, Cinantya; Adeline, A.
Journal of Engineering and Technological Sciences Vol 45, No 1 (2013)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (291.634 KB) | DOI: 10.5614/j.eng.technol.sci.2013.45.1.7

Abstract

Cassava is one of Indonesia’s original commodities and contains good nutrition and has high productivity and a relatively low price. Cassava flour has a high potential as a substitute for imported wheat flour that is widely used in noodle production. The main purpose of this research was to develop wet noodles from cassava flour that can compete with wet noodles from wheat flour. The research consisted of experiments with several variations of composition and production method for producing cassava flour-based wet noodles. The best result was then examined for its nutritional value, economical value, and market response, and also a comparison was made between the prepared wet noodles and the standard noodles made from wheat flour. The analysis was based on five characteristics: taste, texture, chewiness, aroma, and appearance. Relations between these characteristics with composition, materials used, and methods applied are discussed. The developed cassava flour-based wet noodle meets physical, nutritional, and economical standards. Raw materials of the noodle were cassava flour and a wheat flour composite with a 5:1 ratio, egg, gluten, soda-ash, water, and vegetable oil, while the process was completed in multiple stages. Market response showed that the cassava flour-based wet noodles were 80% similar to wheat-flour noodles.

Page 11 of 127 | Total Record : 1267

 9   10   11   12   13 

Filter by Year

2003 2023


Reset
Filter By Issues
All Issue Vol. 55 No. 6 (2023) Vol. 55 No. 5 (2023) Vol. 55 No. 4 (2023) Vol. 55 No. 3 (2023) Vol. 55 No. 2 (2023) Vol. 55 No. 1 (2023) Vol. 54 No. 6 (2022) Vol. 54 No. 5 (2022) Vol. 54 No. 4 (2022) Vol. 54 No. 3 (2022) Vol. 54 No. 2 (2022) Vol. 54 No. 1 (2022) Vol. 53 No. 6 (2021) Vol. 53 No. 5 (2021) Vol. 53 No. 4 (2021) Vol. 53 No. 3 (2021) Vol. 53 No. 2 (2021) Vol. 53 No. 1 (2021) Vol. 52 No. 6 (2020) Vol. 52 No. 5 (2020) Vol. 52 No. 4 (2020) Vol. 52 No. 3 (2020) Vol 52, No 3 (2020) Vol 52, No 2 (2020) Vol. 52 No. 2 (2020) Vol. 52 No. 1 (2020) Vol 52, No 1 (2020) Vol 51, No 6 (2019) Vol. 51 No. 6 (2019) Vol. 51 No. 5 (2019) Vol 51, No 5 (2019) Vol 51, No 4 (2019) Vol. 51 No. 4 (2019) Vol 51, No 3 (2019) Vol. 51 No. 3 (2019) Vol 51, No 2 (2019) Vol. 51 No. 2 (2019) Vol 51, No 2 (2019) Vol 51, No 1 (2019) Vol 51, No 1 (2019) Vol. 51 No. 1 (2019) Vol. 50 No. 6 (2018) Vol 50, No 6 (2018) Vol 50, No 6 (2018) Vol. 50 No. 5 (2018) Vol 50, No 5 (2018) Vol 50, No 5 (2018) Vol. 50 No. 4 (2018) Vol 50, No 4 (2018) Vol 50, No 4 (2018) Vol 50, No 3 (2018) Vol 50, No 3 (2018) Vol. 50 No. 3 (2018) Vol 50, No 2 (2018) Vol 50, No 2 (2018) Vol. 50 No. 2 (2018) Vol. 50 No. 1 (2018) Vol 50, No 1 (2018) Vol 49, No 6 (2017) Vol. 49 No. 6 (2017) Vol 49, No 6 (2017) Vol. 49 No. 5 (2017) Vol 49, No 5 (2017) Vol 49, No 5 (2017) Vol 49, No 4 (2017) Vol 49, No 4 (2017) Vol. 49 No. 4 (2017) Vol. 49 No. 3 (2017) Vol 49, No 3 (2017) Vol 49, No 3 (2017) Vol 49, No 2 (2017) Vol. 49 No. 2 (2017) Vol 49, No 2 (2017) Vol 49, No 1 (2017) Vol. 49 No. 1 (2017) Vol. 48 No. 6 (2016) Vol 48, No 6 (2016) Vol 48, No 6 (2016) Vol. 48 No. 5 (2016) Vol 48, No 5 (2016) Vol 48, No 5 (2016) Vol 48, No 4 (2016) Vol. 48 No. 4 (2016) Vol. 48 No. 3 (2016) Vol 48, No 3 (2016) Vol. 48 No. 2 (2016) Vol 48, No 2 (2016) Vol 48, No 1 (2016) Vol. 48 No. 1 (2016) Vol. 47 No. 6 (2015) Vol 47, No 6 (2015) Vol. 47 No. 5 (2015) Vol 47, No 5 (2015) Vol 47, No 4 (2015) Vol. 47 No. 4 (2015) Vol. 47 No. 3 (2015) Vol 47, No 3 (2015) Vol. 47 No. 2 (2015) Vol 47, No 2 (2015) Vol 47, No 1 (2015) Vol. 47 No. 1 (2015) Vol 46, No 4 (2014) Vol. 46 No. 4 (2014) Vol 46, No 3 (2014) Vol. 46 No. 3 (2014) Vol. 46 No. 2 (2014) Vol 46, No 2 (2014) Vol. 46 No. 1 (2014) Vol 46, No 1 (2014) Vol. 45 No. 3 (2013) Vol 45, No 3 (2013) Vol 45, No 2 (2013) Vol. 45 No. 2 (2013) Vol. 45 No. 1 (2013) Vol 45, No 1 (2013) Vol 44, No 3 (2012) Vol. 44 No. 3 (2012) Vol. 44 No. 2 (2012) Vol 44, No 2 (2012) Vol 44, No 1 (2012) Vol. 44 No. 1 (2012) Vol. 43 No. 3 (2011) Vol 43, No 3 (2011) Vol 43, No 2 (2011) Vol. 43 No. 2 (2011) Vol 43, No 1 (2011) Vol. 43 No. 1 (2011) Vol 42, No 2 (2010) Vol. 42 No. 2 (2010) Vol 42, No 1 (2010) Vol. 42 No. 1 (2010) Vol. 41 No. 2 (2009) Vol 41, No 2 (2009) Vol. 41 No. 1 (2009) Vol 41, No 1 (2009) Vol 40, No 2 (2008) Vol. 40 No. 2 (2008) Vol. 40 No. 1 (2008) Vol 40, No 1 (2008) Vol 39, No 2 (2007) Vol. 39 No. 2 (2007) Vol 39, No 1 (2007) Vol. 39 No. 1 (2007) Vol. 38 No. 2 (2006) Vol 38, No 2 (2006) Vol. 38 No. 1 (2006) Vol 38, No 1 (2006) Vol 37, No 2 (2005) Vol. 37 No. 2 (2005) Vol. 37 No. 1 (2005) Vol 37, No 1 (2005) Vol 36, No 2 (2004) Vol. 36 No. 2 (2004) Vol 36, No 1 (2004) Vol. 36 No. 1 (2004) Vol. 35 No. 2 (2003) Vol 35, No 2 (2003) Vol 35, No 1 (2003) Vol. 35 No. 1 (2003) More Issue