cover
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
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.
Articles 485 Documents
Water Quality of Rivers and Ponds on DKI Jakarta Hendrawan, Diana
Makara Journal of Technology Vol. 9, No. 1
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Water Quality of Rivers and Ponds on DKI Jakarta. Thirteen big rivers, some small rivers, and 40 ponds spread over districts at Jakarta city are potential to support human being life. As the population is growing and the usage of stream water is increasing, the condition and quality of rivers and ponds are changing. Crowd housing can affect rivers and ponds pollution, as the people awareness about clean and healthy environment is less. Stream water pollution assessment can be done by counting the effect of pollutant to life of stream water organisms. This assessment unit could be classified into physics, chemical, and biological parameter. To know the water quality, those parameters are transformed into one single value, that is Water Quality Index. The calculation result of Water Quality Index value shows that 83 % of rivers and 79 % of ponds are bad. This condition is caused by less people and government awareness to maintain rivers and ponds.
Flexi Radio Base Station (RBS) Performance Analysis of Voice and Trafic on Kota 2 Jakarta Barat Base Station Control (BSC) Ferdian, Mushfar; Zulkifli, Fitri Yuli
Makara Journal of Technology Vol. 9, No. 1
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Flexi Radio Base Station (RBS) Performance Analysis of Voice and Trafic on Kota 2 Jakarta Barat Base Station Control (BSC). The CDMA 2000 technology uses circuit switch method to handle voice traffic and packet switch method to handle data traffic between the user and RBS (Radio Base Station). These two parameters can be used to measure performance of the network generally, so it is necessary to optimize them. This paper analyze the performance of RBS by measuring its parameters such as set up failure ratio, drop ratio, and occupancy. Furthermore, the traffic increment is calculated too in order to provide information for improvement in the future. Through the analysis, it is realized that a way to improve configuring it uniquely based on its area of scope. Some RBS need soon, but some others don’t. Beside of that, it is also known that the voice communication effectively while data communication roughly.
Synthesis Dibenzyl Terephthalate Through Depolimerization of Poly (ethylene terephthalate) as Alternative of Waste Plastics Recycling Suwardi, Suwardi; Partana, Crys Fajar; Salim, Agus; Anitasari, Dyah
Makara Journal of Technology Vol. 9, No. 1
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Synthesis Dibenzyl Terephthalate Through Depolimerization of Poly(ethylene terephthalate) as Alternative of Waste Plastics Recycling. Synthesis dibenzyl terephathalate were done through PET degradation by refluxing in benzyl alcohol at 145oC temperature for 20, 24, and 28 hours in the presence of zinc acetate catalyst. The result of degradation was purified by recristalization in methanol and then melting point (mp), FTIR, 1H NMR spectra, and TLC spot were determined. The melting point of product degradation for 28 hours was 98-99 oC. Based FTIR spectra known that compunds of product degradation have OH, C=O, C-O, CH, monosubstituted benzene, disubstituted benzene groups, while on 1H NMR spectra showed chemical shift at 8.2 ppm (s, 10 H of monosubtituted benzene), 7.5 ppm (s, 9 H consist of 4 H disubstituted benzene and 5 H of aromatic benzyl alcohol), 5.4 ppm (s, 1 H from OH benzyl alcohol), 4.8 ppm (s, 4 H of methylene), and 2.9 ppm (s, 7 H of other traces). The single spot of TLC plate indicated that product degradation for 28 hours might be a single compund. Based these characterization concluded that compound of product degradation was dibenzyl terephthalate contains benzyl alcohol and other traces.
Time Domain Characterization of 1-2 GHz Circular-ended Bowtie Antenna Using Normalizad Impulse Response Suryana, Joko; Suksmono, Andriyan B.; Mengko, Tati R.
Makara Journal of Technology Vol. 9, No. 1
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Time Domain Characterization of 1-2 GHz Circular-ended Bowtie Antenna Using Normalizad Impulse Response. Frequency domain analysis is a powerful and compact tool for characterizing the antenna parameters such as gain, radiation pattern and the impedance as a function of frequency. However, if time or space is a major concern, such as in the GPR appication, the time domain analysis would be a very important tool due to their unique capability for determining the echo delay and range profile of target image. In this paper, we will describe the classical theory of system characterization in time domain, and then also propose the mathematical model for characterizing the 1 – 2 GHz circular-ended Bowtie antenna. From the measurement results, we concluded that the implemented Bowtie antenna has good normalized impulse response with very small ringing, so it is suitable for GPR applications.
3D Modelling With Linear Approaches Using Geometric Primitives Zuliansyah, Mochammad
Makara Journal of Technology Vol. 9, No. 1
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In this paper, we study linear approaches for 3D model acquisition from non-calibrated images. First, the intrinsic and extrinsic camera calibration is taken into consideration. In particular, we study the use of a specific calibration primitive: the parallelepiped. Parallelepipeds are frequently present in man-made environments and naturally encode the affine structure of the scene. Any information about their euclidean structure (angles or ratios of edge lengths), possibly combined with information about camera parameters is useful to obtain the euclidean reconstruction. We propose an elegant formalism to incorporate such information, in which camera parameters are dual to parallelepiped parameters, i.e. any knowledge about one entity provides constraints on the parameters of the others. Consequently, an image a parallelepiped with known Euclidean structure allows to compute the intrinsic camera parameters, and reciprocally, a calibrated image of a parallelepiped allows to recover its euclidean shape (up to size). On the conceptual level, this duality can be seen as an alternative way to understand camera calibration: usually, calibration is considered to be equivalent to localizing the absolute conic or quadric in an image, whereas here we show that other primitives, such as canonic parallelepipeds, can be used as well. While the main contributions of this work concern the estimation of camera and parallelepiped parameters. The complete system allows both calibration and 3D model acquisition from a small number of arbitrary images with a reasonable amount of user interaction.
Dipole Magnetization Effect to Kerosene Characteristics Chalid, Mochamad; Saksono, Nelson; Adiwar, Adiwar; Darsono, Nono
Makara Journal of Technology Vol. 9, No. 1
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Dipole Magnetization Effect to Kerosene Characteristics. Investigation of kerosene characteristics has been done by ex-situ dipole magnetization. The results show that magnetization technique can be able to influence kerosene characteristics. Polarity and viscosity of the kerosene are observed by measuring refractive index and viscosity. An hour of 4330 Gauss flux magnetic will increase refractive index from 1.447 to 1.449 and decrease the viscosity from 1.278 to 1.256. Those changing support de-clustering occurrence and polarity increment of kerosene molecule. Gas chromatography and infrared result show that those changing do not alter kerosene structure and composition.
Design of Product Placement Layout In Retail Shop Using Market Basket Analysis Surjandari, Isti; Seruni, Annury Citra
Makara Journal of Technology Vol. 9, No. 2
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Retailing is an industry with high level of competition. It is a customer-based industry which depends on how it could be aware of what the customers’ needs and requirements are. One technique most used in supermarkets is the mix merchandise. The purpose of this paper is to identify associated products, which then grouped in mix merchandise with the use of market basket analysis. This association between products then will be applied in the design layout of the product in the supermarket. The process of identifying the related products bought together in one transaction is done by using data mining technique. Apriori algorithm is chosen as a method in the data mining process. Using WEKA (Waikato Environment for Knowledge Analysis) software, the association rule between products is calculated. The results found five category association rules and fourteen sub-category association rules. These associations then will be interpreted as confidence and support to become consideration for the product layout.
Development of Low Frequency Vibration Method of Direct-Write Deposition Relevant to Layer Manufacturing Application Widyanto, Susilo Adi; Tontowi, Alva Edy; Jamasri, Jamasri; Budi Rochardjo, Heru Santosa
Makara Journal of Technology Vol. 9, No. 2
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The research of deposition process is the first step in development process of multi materials selective laser sintering. The deposition process enables to settle multi materials powder in horizontal formation on one layer. In this research we use low frequency (70 - 200Hz) to vibrate a hopper nozzle in which powder is settled. The research method consists of two steps, the first step is to determine flow-ability parameters and the second is to join flow ability parameter with other parameters such that the line width can be controlled. The results show that the line width depends on uniformity of particle size, particle size, frequency of vibration, deposition gap, particle shape and feed-rate of hopper-nozzle.
Production Hydrogen And Nanocarbon Via Methane Decomposition Using Ni-Based Catalysts. Effect Of Acidity And Catalyst Diameter Purwanto, Widodo W.; Nasikin, M.; Saputra, E.; Song, L.
Makara Journal of Technology Vol. 9, No. 2
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Objectives of this research are mainly to study impacts of acidity strength (by varying amount of precipitant and loading Al-Si) and the effect of nickel particle size (by varying calcinations temperature) on decomposition reaction performances. In this research, high-nickel-loaded catalyst is prepared with two methods. Ni-Cu/Al catalysts were prepared with co-precipitation method. While the Ni-Cu/Al-Si catalyst were prepared by combined co-precipitation and sol-gel method. The direct cracking of methane was performed in 8mm quartz fixed bed reactor at atmospheric pressure and 500-700°C. The main results showed that the Al content of catalyst increases with the increasing amount of precipitant. The activity of catalyst increases with the increasing of catalyst’s acidity to the best possible point, and then increasing of acidity will reduce the activity of catalyst. Ni-Cu/4Al and Ni-Cu/11Al deactivated in a very short time hence produced fewer amount of nanocarbon, while Ni-Cu/15Al was active in a very long period. The most effective catalyst is Ni-Cu/22Al, which produced the biggest amount of nanocarbon (4.15 g C/g catalyst). Ni catalyst diameter has significant effect on reaction performances mainly methane conversion and product yield. A small Ni crystal size gave a high methane conversion, a fast deactivation and a low carbon yield. Large Ni particle diameter yielded a slow decomposition and low methane conversion. The highest methane conversion was produced by catalyst diameter of 4 nm and maximum yield of carbon of 4.08 g C/ g catalyst was achieved by 15.5 nm diameter of Ni catalyst.
Synthesis of Fuel Cell Membrane: Copolymerization of Styrene on ETFE Film by Grafted pre-Irradiation Yohan, Yohan; Nur, Rifai M.; Hendrajaya, Lilik; Siradj, E. S.
Makara Journal of Technology Vol. 9, No. 2
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Synthesis of Fuel Cell Membrane: Copolymerization of Styrene on ETFE Film by Grafted pre-Irradiation. Preirradiation Grafting styrene monomer on ETFE film has been prepared. Research has been performed by γ-ray radiation at various total dose from 2.5 – 12.5 kGy and various dose rate from 1.3 – 1.9 kGy/hour. Irradiated copolymer is then grafted by styrene monomer in various solvent: ethanol, 2-propanol, and toluene, various concentration from 20 – 70% volume, various temperature from 50 – 90oC, and various grafting time from 2 – 12 hours. The results showed that percent of grafting is increase with increase of total dose and decrease of rate dose. The optimum experiment conditions are obtained at total dose 10 kGy, dose rate 1,9 kGy/hour, 2-propanol solvent, 40% volume styrene, 4 hours grafting time, and 70oC grafting temperature.

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