Open Access. Powered by Scholars. Published by Universities.®

Ocean Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

1,146 Full-Text Articles 2,520 Authors 529,689 Downloads 50 Institutions

All Articles in Ocean Engineering

Faceted Search

1,146 full-text articles. Page 48 of 50.

Characterization Of Surface Active Shell Charcoal Nyamplung Seeds (Calophyllum Inophyllum Linn), Santiyo Wibowo, Wasrin Syafi, Gustan Pari 2011 Balai Penelitian Kehutanan Aek Nauli, Kampus Kehutanan Terpadu Aek Nauli, Sibaganding, Parapat, Sumatera Utara 1174, Indonesia

Characterization Of Surface Active Shell Charcoal Nyamplung Seeds (Calophyllum Inophyllum Linn), Santiyo Wibowo, Wasrin Syafi, Gustan Pari

Makara Journal of Technology

Characterization of Surface Active Shell Charcoal Nyamplung Seeds (Calophyllum inophyllum Linn). Chemical and physical activation of nyamplung shell with 0%, 5%, and 10% H3PO4 for 60 and 120 minutes has been carried out to prepare activated charcoal. The purpose of this experiment was to look into the characteristic of nyamplung shell activated charcoal surface. Nyamplung shell was carbonized into charcoal, then activated by immersion in H3PO4 solution using 0%, 5% and 10%, for 24 hours, and heated in retort at two temperatures (700 and 800 oC) and two duration (60 and 120 minutes). The material were characterized by fourier transform …


An Investigation Into The Resistance/Powering And Seakeeping Characteristics Of River Catamaran And Trimarana, Murdijanto Murdijanto, I Ketut Aria Pria Utama, Andi Jamaluddin 2011 Department of Naval Architecture and Shipbuilding Engineering, FTK, ITS, Surabaya 60111, Indonesia

An Investigation Into The Resistance/Powering And Seakeeping Characteristics Of River Catamaran And Trimarana, Murdijanto Murdijanto, I Ketut Aria Pria Utama, Andi Jamaluddin

Makara Journal of Technology

The increase of fuel price has caused fleet operational and shipping business to be in danger situation. The fuel consumption of a ship is influenced by ship volume or wetted area which contributes directly to the increase of ship resistance and the size of main engine. In order to find out the appropriate answers, a series of investigation into river transportation using monohull, catamaran and trimaran types of vessel was carried out. The work focused on the estimation of total resistance and powering as well as seakeeping characteristics and carried out experimentally using tank test and numerically using a ship …


Determining The Standard Value Of The Oily Distortion Of Acquisition The Fingerprint Images, Rahmat Syam, Mochamad Hariadi, Mauridhi Hery Purnomo 2011 Jurusan Matematika, Fakultas MIPA, Universitas Negeri Makassar, Makassar 90222, Indonesia

Determining The Standard Value Of The Oily Distortion Of Acquisition The Fingerprint Images, Rahmat Syam, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

Determining the Standard Value of the Oily Distortion of Acquisition the Fingerprint Images. This research describes a novel procedure for determining the standard value of the oily distortion of acquisition the fingerprint images based on the score of clarity and ridge-valley thickness ratio. The fingerprint image is quantized into blocks size 32 x 32 pixels. Inside each block, an orientation line, which perpendicular to the ridge direction, is computed. The center of the block along the ridge direction, a two-dimension (2-D) vector V1 (slanted square) with the pixel size 32 x 13 pixels can be extracted and transformed to a …


Are Ieee 754 32-Bit And 64-Bit Binary Floating-Point Accurate Enough?, Bernaridho Hutabarat, I Ketut Eddy Purnama, Mochamad Hariadi, Mauridhi Hery Purnomo 2011 Department of Electrical Engineering, Faculty of Industrial Engineering, Institut Teknologi Sepuluh Nopember, Sukolilo, Surabaya 60111, Indonesia

Are Ieee 754 32-Bit And 64-Bit Binary Floating-Point Accurate Enough?, Bernaridho Hutabarat, I Ketut Eddy Purnama, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

This paper describes a research toward the accuracy of floating-point values, and effort to reveal the real accuracy. The methods used in this research paper are assignment of values, assignment of value of arithmetic expressions, and output the values using floating-point value format that helps reveal the accuracy. The programming-tool used are Visual C# 9, Visual C++ 9, Java 5, and Visual BASIC 9. These tools run on top of Intel 80 x 86 hardware. The results show that 1*10-x cannot be accurately represented, and the approximate accuracy ranges only from 7 to 16 decimal digits.


Ergonomic Analysis Of Garment Industry Using Posture Evaluation Index (Pei) In Virtual Environment, Erlinda Muslim, Boy Nurtjahyo, Romadhani Ardi 2011 Departemen Teknik Industri, Fakultas Teknik, Universitas Indonesia, Depok 16424, Indonesia

Ergonomic Analysis Of Garment Industry Using Posture Evaluation Index (Pei) In Virtual Environment, Erlinda Muslim, Boy Nurtjahyo, Romadhani Ardi

Makara Journal of Technology

Ergonomic Analysis of Garment Industry using Posture Evaluation Index (PEI) in Virtual Environment. This research tried to study, in a virtual environment, the ergonomics of four divisions in garment industry: cutting division, sewing division, button division, and finishing division. Variables that influence the working conditions in each division are different; depend on the real situations that happened. The purpose is to assess the real working conditions based on ergonomics study using Posture Evaluation Index (PEI). PEI integrates the scores of low back analysis (LBA), ovako working posture (OWAS), and rapid upper limb assessment (RULA). Analysis phase was done using digital …


Formation Of Caco3 Particle And Conductivity Of Na2co3 And Cacl2 Solution Under Magnetic Field On Dynamic Fluid System, Nelson Saksono, Setijo Bismo, Roekmijati Widaningroem, Azwar Manaf 2011 Department of Chemical Engineering, Faculty of Engineering, University of Indonesia, Depok 16424, Indonesia

Formation Of Caco3 Particle And Conductivity Of Na2co3 And Cacl2 Solution Under Magnetic Field On Dynamic Fluid System, Nelson Saksono, Setijo Bismo, Roekmijati Widaningroem, Azwar Manaf

Makara Journal of Technology

Hard water causes the CaCO3 scale formation on the pipe walls and heat exchanger equipments in industrial or domestic water processes. A great number of experimental researches on the prevention of the CaCO3 precipitation process by magnetic field have been carried out. In this research, Na2CO3 and CaCl2 solutions was magnetized in the circulated flow condition (dynamic fluid system). The velocity of fluid and the circulation time was modified to examine its influences to the magnetization process. CaCO3 content was measured by titration method of EDTA complexometry. Conductivity test was conducted to find out hydrate ion bonding. The results showed …


Two-Class Classification With Various Characteristics Based On Kernel Principal Component Analysis And Support Vector Machines, Ivanna Kristianti Timotius, Iwan Setyawan, Andreas Ardian Febrianto 2011 Department of Electronic Engineering, Satya Wacana Christian University, Salatiga 50711, Indonesia

Two-Class Classification With Various Characteristics Based On Kernel Principal Component Analysis And Support Vector Machines, Ivanna Kristianti Timotius, Iwan Setyawan, Andreas Ardian Febrianto

Makara Journal of Technology

Two class pattern classification problems appeared in many applications. In some applications, the characteristic of the members in a class is dissimilar. This paper proposed a classification system for this problem. The proposed system was developed based on the combination of kernel principal component analysis (KPCA) and support vector machines (SVMs). This system has been implemented in a two class face recognition problem. The average of the classification rate in this face image classification is 82.5%.


Advanced Underwater Vehicle Navigation, M. Jordan Stanway 2011 Florida Institute of Technology

Advanced Underwater Vehicle Navigation, M. Jordan Stanway

Link Foundation Ocean Engineering and Instrumentation Fellowship Reports

Underwater vehicles–both manned and unmanned–are critical in our efforts to explore and study the depths of the ocean. Most underwater sensors possess a relatively small field of view; this means they must be carried over large distances to achieve high spatial coverage and resolution. The vast amount of data these sensors collect is much more valuable if the location of the vehicle is precisely known at the time the data is collected. This gives rise to the maxim: The data is only as good as the navigation. Navigation remains a challenging problem for underwater vehicles. Fundamental limitations of sensing technology …


Wimax Implementation As Existing Hotspot Network Backhaul In Jakarta, Djamhari Sirat, Muhamad Asvial, Luther B. Marpaung 2010 Departemen Teknik Elektro, Fakultas Teknik, Universitas Indonesia, Depok 16424, Indonesia

Wimax Implementation As Existing Hotspot Network Backhaul In Jakarta, Djamhari Sirat, Muhamad Asvial, Luther B. Marpaung

Makara Journal of Technology

WiMAX Implementation as Existing Hotspot Network Backhaul in Jakarta The development of Broadband Wireless Access (BWA), such as WiMAX, as a global standard for data transmission media has been used by high speed internet access provider. WiMAX application which supported by capabilities of interoperability, flexibility and commercial aspect make the internet services become more efficient, cheaper and easier to the customer. This phenomenon should be responded by ISPs. Based on technical and financial aspect in deciding the implementation of Wireless Network with WiMAX technology as a substitute, this research will observe and analyze the projection of WiMAX technology implementation as …


Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo 2010 Agricultural Engineering Department, Agricultural Technology Faculty, University of Gadjah Mada, Bulaksumur, Yogyakarta 55281, Indonesia

Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

The visualization of plant growth modeling using computer simulation has rarely been conducted with Lindenmayer System (L-System) approach. L-System generally has been used as framework for improving and designing realistic modeling on plant growth. It is one kind of tools for representing plant growth based on grammar sintax and mathematic formulation. This research aimed to design modeling and visualizing plant growth structure generated using L-System. The environment on modeling design used three dimension graphic on standart OpenGL format. The visualization on system design has been developed by some of L-System grammar, and the output graphic on three dimension reflected on …


Immobilization Of Saccharomyces Cerevisiae In Rice Hulls For Ethanol Production, Edita Martini, Dian Andriani, Sriramulu GobiKrishnan, Kyeong Eop Kang, Surn-Teh Bark, Changshin Sunwoo, Bambang Prasetya, Don-Hee Park 2010 Interdisciplinary Program of Graduate School for Bioenergy and Biomaterials, Chonnam National University, Gwangju 500-757, South Korea

Immobilization Of Saccharomyces Cerevisiae In Rice Hulls For Ethanol Production, Edita Martini, Dian Andriani, Sriramulu Gobikrishnan, Kyeong Eop Kang, Surn-Teh Bark, Changshin Sunwoo, Bambang Prasetya, Don-Hee Park

Makara Journal of Technology

The whole cell immobilization in ethanol fermentation can be done by using natural carriers or through synthetic carriers. All of these methods have the same purpose of retaining high cell concentrations within a certain defined region of space which leads to higher ethanol productivity. Lignocellulosic plant substance represents one of highly potential sources in ethanol production. Some studies have found that cellulosic substances substances can also be used as a natural carrier in cell immobilization by re-circulating pre-culture medium into a reactor. In this experiment, rice hulls without any treatment were used to immobilize Saccharomyces cerevisiae through semi solid state …


Separation Study Of Titanomagnetite Fe3-Xtixo4 From Natural Sand At Indramayu, West Java, Sunaryo Sunaryo, Iwan Sugihartono 2010 Jurusan Fisika, FMIPA, Universitas Negeri Jakarta, Jakarta 13220, Indonesia

Separation Study Of Titanomagnetite Fe3-Xtixo4 From Natural Sand At Indramayu, West Java, Sunaryo Sunaryo, Iwan Sugihartono

Makara Journal of Technology

Separation Study of Titanomagnetite Fe3-xTixO4 from Natural Sand at Indramayu, West Java. Titanomagnetite FeTiO4 has been obtained from metal sand which is separated from natural sand at Indramayu using magnetic separator with the magnetic field 0,3 Tesla. This method can improve titanomagnetite content from 32% to 63,6%. According to X-ray diffractometer (XRD) and data processing by general structure analyses system (GSAS) with χ2= 1,454 and Wrp = 0,1142 as correction factor of the peak to peak intensities, we conclude that χ2 about 0 and Wrp aproximately 10%. It indicates the datas with the error merely 0,1 can be accepted. Furthermore, …


Hydrogen Absorption Induced Slow Crack Growth In Austenitic Stainless Steels For Petrochemical Pressure Vessel Industries, Ronnie Higuchi Rusli 2010 Graduate Program of Engineering, University of Indonesia, Jakarta 10430, Indonesia Visiting Research Scientist at Sumittomo Steel Industries Ltd., Research & Development Center, Japan

Hydrogen Absorption Induced Slow Crack Growth In Austenitic Stainless Steels For Petrochemical Pressure Vessel Industries, Ronnie Higuchi Rusli

Makara Journal of Technology

Type 304L and type 309 austenitic stainless steels were tested either by exposed to gaseous hydrogen or undergoing polarized cathodic charging. Slow crack growth by straining was observed in type 304L, and the formation of α‘ martensite was indicated to be precursor for such cracking. Gross plastic deformation was observed at the tip of the notch, and a single crack grew slowly from this region in a direction approximately perpendicular to the tensile axis. Martensite formation is not a necessary condition for hydrogen embrittlement in the austenitic phase.


Simulation On The Use Of Losat Data For Rice Field Mapping, Bambang H. Trisasongko, Dyah R. Panuju, Boedi Tjahjono, Baba Barus, Hari Wijayanto, Mahmud A. Raimadoya, Irzaman Irzaman 2010 Tim KKP3T-Padi, Departemen Ilmu Tanah dan Sumberdaya Lahan, Institut Pertanian Bogor, Bogor 16680, Indonesia

Simulation On The Use Of Losat Data For Rice Field Mapping, Bambang H. Trisasongko, Dyah R. Panuju, Boedi Tjahjono, Baba Barus, Hari Wijayanto, Mahmud A. Raimadoya, Irzaman Irzaman

Makara Journal of Technology

Simulation on the Use of LOSAT Data for Rice Field Mapping. Since the launch of LAPAN-TUBSAT satellite in 2007, Indonesia has been developing mission on earth observation missions for various applications. The next generation mission, called LAPAN-ORARI Satellite (LOSAT), is currently under development and expected to be launched in 2011. In order to facilitate the applications, a thorough assessment of the sensor should be made. This paper presents an examination of simulated LOSAT data for rice monitoring and mapping purposes coupled with QUEST statistical tree. We found that three-band simulated LOSAT data were suitable for the task with reasonably high …


Development Of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach, Bagiyo Suwasono, Sjarief Widjaja, Achmad Zubaydi, Zaed Yuliadi, I Nyoman Budiantara 2010 Jurusan Teknik Perkapalan, FTK, Institut Teknologi Sepuluh Nopember, Surabaya 60111, Indonesia

Development Of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach, Bagiyo Suwasono, Sjarief Widjaja, Achmad Zubaydi, Zaed Yuliadi, I Nyoman Budiantara

Makara Journal of Technology

Development of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach. Ability of production processes associated with state-of-the-art technology, which allows the shipbuilding, is customized with modern equipment. It will give impact to level of productivity and competitiveness. This study proposes a nonparametric regression cubic spline approach with 1 knot, 2 knots, and 3 knots. The application programs Tibco Spotfire S+ showed that a cubic spline with 2 knots (4.25 and 4.50) gave the best result with the value of GCV = 56.21556, and R2 = 94.03%.Estimation result of cubic spline with 2 knots for the PT. Batamec shipyard …


Shaft Torsional Vibration Response Of Vertical Axis Ocean Current Turbine Model Due To Torque Excitation, Adi Wirawan Husodo, I Ketut Aria Pria Utama, I Made Ariana 2010 Jurusan Teknik Permesinan Kapal, Politeknik Perkapalan Negeri Surabaya, Surabaya 60111, Indonesia

Shaft Torsional Vibration Response Of Vertical Axis Ocean Current Turbine Model Due To Torque Excitation, Adi Wirawan Husodo, I Ketut Aria Pria Utama, I Made Ariana

Makara Journal of Technology

Shaft Torsional Vibration Response of Vertical Axis Ocean Current Turbine Model Due to Torque Excitation. The current research aimed to study the torsional vibration response of Vertical Axis Ocean Current Turbine due to randomly torque excitation pattern, owing to the variety of ocean current velocity. The turbine model is composed of 3 aluminum blades of NACA 0018 connected to steel shaft. Turbine dimensions are 10 cm of chord, 1.8 cm of chamber and 100 cm of span. The variation of ocean current velocity is 0.5 m/s, 1.0 m/s, 1.5 m/s, 2.0 m/s, 2.5 m/s and 3.0 m/s. The Model has …


Dye Sensitized Solar Cell With Conventionally Annealed And Post-Hydrothermally Treated Nanocrystalline Semiconductor Oxide Tio2 Derived From Sol-Gel Process, Akhmad Herman Yuwono, Badrul Munir, Alfian Ferdiansyah, Arif Rahman, Wulandari Handini 2010 Department of Metallurgy and Materials Engineering, Faculty of Engineering, University of Indonesia, Depok 16424, Indonesia

Dye Sensitized Solar Cell With Conventionally Annealed And Post-Hydrothermally Treated Nanocrystalline Semiconductor Oxide Tio2 Derived From Sol-Gel Process, Akhmad Herman Yuwono, Badrul Munir, Alfian Ferdiansyah, Arif Rahman, Wulandari Handini

Makara Journal of Technology

Dye-sensitized solar cell (DSSC) is one of the very promising alternative renewable energy sources to anticipate the declination in the fossil fuel reserves in the next few decades and to make use of the abundance of intensive sunlight energy in tropical countries like Indonesia. In the present study, TiO2 nanoparticles of different nanocrystallinity was synthesized via sol−gel process with various water to inorganic precursor ratio (Rw) of 0.85, 2.00 and 3.50 upon sol preparation, followed with subsequent drying, conventional annealing and post-hydrothermal treatments. The resulting nanoparticles were integrated into the DSSC prototype and sensitized with an organic dye made of …


An Empirical Model For Build-Up Of Sodium And Calcium Ions In Small Scale Reverse Osmosis, Subriyer Nasir 2010 Chemical Engineering Department, Faculty of Engineering, Sriwijaya University, Inderalaya Ogan Ilir 30662, Sumatera Selatan, Indonesia

An Empirical Model For Build-Up Of Sodium And Calcium Ions In Small Scale Reverse Osmosis, Subriyer Nasir

Makara Journal of Technology

A simple models for predicting build-up of solute on membrane surface were formulated in this paper. The experiments were conducted with secondary effluent, groundwater and simulated feed water in small-scale of RO with capacity of 2000 L/d. Feed water used in the experiments contained varying concentrations of sodium, calcium, combined sodium and calcium. In order to study the effect of sodium and calcium ions on membrane performance, experiments with ground water and secondary effluent wastewater were also performed. Build-up of salts on the membrane surface was calculated by measuring concentrations of sodium and calcium ions in feed water permeate and …


The Effect Of Enzymatic Hydrolysis On The Properties Of Protein Hydrolysate From Paddy Mushroom, Niken Widya Palupi, Wiwik Siti Windrati, Tamtarini Tamtarini 2010 Department of Product Agricultural Technology, Faculty of Agricultural Technology, University of Jember, Jember 68121, Indonesia

The Effect Of Enzymatic Hydrolysis On The Properties Of Protein Hydrolysate From Paddy Mushroom, Niken Widya Palupi, Wiwik Siti Windrati, Tamtarini Tamtarini

Makara Journal of Technology

Protein hydrolysate was prepared from Paddy (Volvariella volvaceae) mushroom. Hydrolysis uses commercially protease available Protamex ™ with enzyme concentration of 0.1% (w/w). Hydrolysis was performed at three different temperatures (room temperature, 40 °C, and 50 °C) with different incubation periods (60, 90, and 120 minutes). Enzyme inactivation was done in 90 °C for 3 minutes. Yield and degree of hydrolysis ranged from 94.76% to 99.55% and 19.06% to 24.59%. Protein solubility was about 89–11,8%. The longer time of hydrolysis, the darker the color of protein hydrolysate. Protein hydrolysate which has hydrolysis at 50 °C for 120 minutes has the highest …


Effect Of Diafiltration On Preparation Of Fermented Mung Beans Concentrate As Probiotic Savory Flavor Through Ultrafiltration Membrane, Aspiyanto Aspiyanto, Agustine Susilowati 2010 Research Center for Chemistry, Indonesian Institute of Sciences, Kawasan Puspiptek, Serpong, Tangerang 15314, Indonesia

Effect Of Diafiltration On Preparation Of Fermented Mung Beans Concentrate As Probiotic Savory Flavor Through Ultrafiltration Membrane, Aspiyanto Aspiyanto, Agustine Susilowati

Makara Journal of Technology

Diafiltration by means of the ultrafiltration system of probiotic fermented Mung beans (Phaseolus radiatus L.) concentrate has been performed to reduce or eliminate salts and smaller impurities than the nominal cut-off of the membrane of 20,000 nominal weight cut-off (NWCO). These processes have been conducted as an attempt in order to get a probiotic product with organoleptic acceptability, composition, and the optimal total lactic acid bacteria (LAB) counts because the presence of salts will affect on the viability of LAB and the cell lysis of LAB and limit its utility in food products. Concentrate of probiotic mung beans was prepared …


Digital Commons powered by bepress