cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Dr. Basari
Contact Email
basari.st@ui.ac.id
Phone
+6221-29120943
Journal Mail Official
editor_mst@ui.ac.id
Editorial Address
Universitas Indonesia ILRC Building, 1st Floor, Depok 16424, Indonesia Kota depok, Jawa barat INDONESIA
Location
Kota depok,
Jawa barat
INDONESIA
Makara Journal of Technology
Published by Universitas Indonesia
ISSN : 23552786     EISSN : 23564539     DOI : https://doi.org/10.7454/mjt
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Electrical & Electronics Engineering Engineering Materials Science & Nanotechnology Mechanical Engineering
MAKARA Journal of Technology is a peer-reviewed multidisciplinary journal committed to the advancement of scholarly knowledge and research findings of the several branches of Engineering and Technology. The Journal publishes new results, original articles, reviews, and research notes whose content and approach are of interest to a wide range of scholars. It also offers rapid dissemination. MAKARA Journal of Technology covers the recent research in several branches of engineering and technology include Electrical & Electronics Engineering, Computer Engineering, Mechanical Engineering, Chemical & Bioprocess Engineering, Material & Metallurgical Engineering, Industrial Engineering, Civil & Architecture Engineering, and Marine Engineering. Criteria used in determining acceptability of contributions include newsworthiness to a substantial part of the engineering & technology and the effect of rapid publication on the research of others. This journal, published three times each year, is where readers look for the advancement of discoveries in engineering and technology.
Arjuna Subject : Teknik (semua kategori) - Teknik (Lain-Lain)
Articles 439 Documents
 1   2   3   4   5 
The Manufacturing Properties Of Galvanised Steel Sheet With Hexagonal And Tetragonal Network Of Circle Holes Saptono, Rahmat
Makara Journal of Technology Vol. 6, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Galvanized steel sheet of 0.8 mm in thickness was drilled with circle holes of 2.5 mm diameter and spacing arranged in tetragonal and hexagonal pattern. The manufacturing properties of specimen were studied through drawing and stretching simulative test. It was concluded from the results that, at high ratio of punch to hole diameter (40/2.5), the drawing properties (LDR) of both square and hexagonal perforated sheet were slightly lower than that of solid sheet, while hexagonal perforated showing LDR somewhat higher than the square one. The stretching properties (LDH) of sheet, however, were much lower than that of solid sheet while the hexagonal perforated exhibiting LDH lower than the square one. Provided the effi ciency factor was well defi ned, which was not effective in the present experiment, the intrinsic drawing properties might be indirectly determined through the simulative test by assuming the perforated materials as an equivalent continuum.
Object Classfification in Computer Vision with Discriminant Analysis Hamzahan, Amir
Makara Journal of Technology Vol. 6, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

A robotic sensor system is always supported by a computer system called ‘computer vision’. The important concept of computer vision is object classfifi cation. In this study two algorithms for object classifi cation in this system will be compared. Firstly, A simple method that do not need complex computation and that considered as an informal method is called binary tree decision structure. This method is based on modest caracteristic decriptors of an object such as vertical line, horizontal line or ellipse line. Unfortunately this method has weakness in recognize an image that contaminated by a noise. Secondly, a more formal method with high variability descriptors. In this contect a multivariate statistical approach named discriminant analysis is proposed as an alternative for object classifi cation. This method is operated by computation of a function called Fisher discriminant function that can be used for separating an object. From the data simulation and analysis for calssifi cation of two object i.e. screw and bolt and three objects i.e. alphabet T,O and S it can be shown that discriminant analysis approach can classify an object better than binary decision algorithm. The superority of discriminant method is especially seen when this method is applied for classifi cation of a noisy image of object.
Making Alloys (TI1 - xAlx) N using plasma CVD technique from AlCl3 Powder, H2 and N2 Gas ,with solvent TiCl4 Moto, Keba
Makara Journal of Technology Vol. 6, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The substitution of Ti atoms by Al atoms in TiN lattice sites to form (Ti1-xAlx)N is clearly demonstrated by the coatings which were deposited on steel substrate and using plasma CVD technique. The presence of Al atoms in TiN lattice site is shown by means of XRD and EDX techniques: lattice parameters decreasing of TiN as the fraction of Al increases (XRD) and precipitation of hexagonal AlN phase (XRD) as the fraction of Al exceeding 0.8 (EDX). The hardness of these coating are just around 30 GPa, which is beyond the values reported in literatures.
Integrating Passenger and Modulo as Learning Tools for Collaborative Engineering Education Ramli, Kalamullah; Schwarz, Frank; Werner, Stefan; Shamsuddin, A Halim; Hunger, Axel
Makara Journal of Technology Vol. 6, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The University of Indonesia (UI), Gerhard Mercator University (GMU), the Universiti Kebangsaan Malaysia (UKM) have agreed to cooperate as partners to develop a joint bachelor (3+1) and masters (1+1) degree, and collaborate in the research fi elds of multimedia- and internet-based learning and application level active networks. This paper describes the introduction of the Offshore Project and the extending of information technology applications to the partner institutions in this international cooperation which would very much enhance the operations of the new initiative in engineering education, which could provide students in far distance with more fl exible learning environment.
The Role of Si3N4 Amorphous Phase in nc-TiN/a-Si3N4 Nanocomposites in Increases the hardness and Thermal Stability Moto, Keba
Makara Journal of Technology Vol. 6, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The role of Si3N4 amorphous phase in nc-TiN/a-Si3N4 nanocomposites will be shown and compared with polycrystalline ZrN/Ni which has no such amorphous phase (non-composites). The presence of amorphous phase Si3N4 increases the hardness of film as well as the toughness of the bulk nanocomposites under indentation load. It has been observed that nc-TiN/a-Si3N4 nanocomposites films has higher thermal stability than ZrN/Ni polycrystalline films.
Analogy Method Development for Cost Estimation of Software Design Sarno, Riyanarto; Buliali, Joko Lianto; Maimunah, Siti
Makara Journal of Technology Vol. 6, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The important aspect of planning and managing software development project is to estimate the cost of a project. There are several methods for estimating the cost of a software development project, and the Analogy method is a method which gives relatively better estimates. This paper shows that the modified Analogy method selects a closer project reference, estimates more accurate project effort and cost. This study enhances the cost estimate technique by including valid and complete cost parameters, therefore the estimate of a project cost is better than the result of the standard Analogy method.
Biodiesel's Characteristics Preparation from Palm Oil S, Tilani Hamid.; Yusuf, Rachman
Makara Journal of Technology Vol. 6, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Biodiesel’s characteristics preparation from palm oil. Using vegetable oils directly as an alternative diesel fuel has presented engine problems. The problems have been attributed to high viscosity of vegetable oil that causes the poor atomization of fuel in the injector system and pruduces uncomplete combustion. Therefore, it is necessary to convert the vegetable oil into ester (metil ester) by tranesterification process to decrease its viscosity. In this research has made biodiesel by reaction of palm oil and methanol using lye (NaOH) as catalyst with operation conditions: constant temperature at 60 oC in atmosferic pressure, palm oil : methanol volume ratio = 5 : 1, amount of NaOH used as catalyst = 3.5 gr, 4.5 gr, 5 gr and 5.5 gr and it takes about one hour time reaction. The ester (metil ester) produced are separated from glycerin and washed until it takes normal pH (6-7) where more amount of catalyst used will decrease the ester (biodiesel) produced. The results show that biodiesels’ properties made by using 3.5 (M3.5) gr, 4.5 gr (M4.5) and 5 (M5.0) gr catalyst close to industrial diesel oil and the other (M5.5) closes to automotive diesel oil, while blending diesel oil with 20 % biodiesel (B20) is able to improve the diesel engine performances.
The Effects of Corrosive Chemicals on Corrosion Rate of Steel Reinforcement Bars: I. Swamp Water Widanarko, Sulistyoweni; Ashadi, Henki W.; Wicaksono, Andri Krisnadi
Makara Journal of Technology Vol. 6, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Most of infrastructures using steel concrete to reinforce the strength of concrete. Steel concrete is so vulnerable to chemical compounds that can cause corrosion. It can happen due to the presence of chemical compounds in acid environment in low pH level. These chemical compounds are SO4 2-, Cl-, NO3 -. There are many swamp area in Indonesia. The acid contents and the concentration of ion sulphate, chlorides, and nitrate are higher in the swamp water than in the ground water .The objective of this research was to find out the influence of corrosive chemicals in the swamp water to the steel concrete corrosion rate. There were two treatment used: (1) emerging ST 37 and ST 60 within 60 days in the ‘polluted’ swamp water, (2) moving the ST 37 up and down periodically in the ‘ polluted’ swamp water. Three variation of ’polluted’ swamp water were made by increasing the concentration of corrosive chemical up to 1X, 5X and 10X respectively. The corrosion rate was measured by using an Immersion Method. The result of Immersion test showed that chloride had the greatest influence to corrosion rate of ST 37 and ST 60 and followed by sulphate and Nitrate. Corrosion rate value for ST 37 is 24.29 mpy and for ST 60 is 22.76 mpy. By moving the sample up and down, the corrosion rate of ST 37 increase up to 37.59 mpy, and chloride still having the greatest influence, followed by sulphate and nitrate.
The Effects of Corrosive Chemicals on Corrosion Rate of Steel Reinforcement Bars: II. Swamp Sludges Ashadi, Henki W.; Widanarko, Sulistyoweni; Gusniani, Irma
Makara Journal of Technology Vol. 6, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

A polluted environment will influence the building age. The objective of this research was to find out the influence of corrosive chemicals within the sludge swamp area with the corrosion rate of steel concrete. Corrosion in steel concrete usually occur in acid area which contain of SO4 2-, Cl- and NO3 -. The research treatment used by emerging ST 37 and ST 60 within 60 days in ‘polluted’ sludge swamp area. Three variation of ‘polluted’ swamp sludge were made by increasing the concentration a corrosive unsure up to 1X, 5X and 10X. The corrosion rate measured by using an Immersion Method. The result of Immersion test showed that sulphate had a greatest influence to corrosion rate of ST 37 and ST 60 and followed by chloride and nitrate. Corrosion rate value for ST 37 was 17.58 mpy and for ST 60 was 12.47 mpy.
The Effect of Ca Content on CaO-Zeolite on Nitrogen Adsorption Capacity Nasikin, Mohammad; Utami, Tania Surya; Siahaan, Agustina TP
Makara Journal of Technology Vol. 6, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

In industry, Ca zeolite is used as nitrogen selective adsorbent with the use of PSA (Pressure Swing Adsorption)/VSA (Vacuum Swing Adsorption) methods. Natural zeolite modified to be Cao-zeolite by ion exchange process using Ca(OH)2. Adsorption test was done on CaO-zeolite with different Ca concentration to understand how it’s adsorption phenomena on oxygen and nitrogen. Adsorption test has been done for CaO-zeolite with Ca concentration = 0,682%, 0,849% and 1,244% to oxygen and nitrogen with equal concentration seperately. Pressure variation has being done three times (5 minutes long each time) adsorption time to analyze the connection between adsorption time and how many moles of nitrogen and oxygen being adsorbed. Adsorption test showed that there is a limit of Ca concentration to make CaO-zeolite more selective to adsorb nitrogen. CaO-zeolite with Ca concentration . 1,125% adsorb nitrogen more selective than oxygen. Because the nitrogen content in air is four times the oxygen so we can conclude that the air adsorption rate by zeolite will be four times the adsorption rate by oxygen. This differences in adsorption rate will make the use for CaO-zeolite as a oxygen enrichment equipment possible.

Page 2 of 44 | Total Record : 439

 1   2   3   4   5 

Filter by Year

2002 2022


Reset
Filter By Issues
All Issue Vol. 26, No. 2 Vol. 26, No. 1 Vol. 25, No. 3 Vol. 25, No. 2 Vol. 25, No. 1 Vol. 24, No. 3 Vol. 24, No. 2 Vol. 24, No. 1 Vol. 23, No. 3 Vol. 23, No. 2 Vol. 23, No. 1 Vol. 22, No. 3 Vol. 22, No. 2 Vol. 22, No. 1 Vol. 21, No. 3 Vol. 21, No. 2 Vol. 21, No. 1 Vol. 20, No. 3 Vol. 20, No. 2 Vol. 20, No. 1 Vol. 19, No. 3 Vol. 19, No. 2 Vol. 19, No. 1 Vol. 18, No. 3 Vol. 18, No. 2 Vol. 18, No. 1 Vol. 17, No. 3 Vol. 17, No. 2 Vol. 17, No. 1 Vol. 16, No. 2 Vol. 16, No. 1 Vol. 15, No. 2 Vol. 15, No. 1 Vol. 14, No. 2 Vol. 14, No. 1 Vol. 13, No. 2 Vol. 13, No. 1 Vol. 12, No. 2 Vol. 12, No. 1 Vol. 11, No. 2 Vol. 11, No. 1 Vol. 10, No. 2 Vol. 10, No. 1 Vol. 9, No. 2 Vol. 9, No. 1 Vol. 8, No. 3 Vol. 8, No. 2 Vol. 8, No. 1 Vol. 7, No. 3 Vol. 7, No. 2 Vol. 7, No. 1 Vol. 6, No. 3 Vol. 6, No. 2 Vol. 6, No. 1 More Issue