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Full-Text Articles in Engineering

A New Calibration Method For Low Cost Mems Inertial Sensor Module, Sheng-Chih Shen, Chia-Jung Chen, Hsin-Jung Huang Dec 2010

A New Calibration Method For Low Cost Mems Inertial Sensor Module, Sheng-Chih Shen, Chia-Jung Chen, Hsin-Jung Huang

Journal of Marine Science and Technology

This paper presents a new calibration method to overcome the challenges of MEMS inertial sensors for underwater navigation. The MEMS inertial sensor module is composed of an accelerometer, a gyroscope and a circuit of signal process. For navigation estimation, it is easy to be influenced by errors which come from MEMS inertial sensors. In general, the sources of error can be categorized into two groups, deterministic type and stochastic type. The former primarily includes bias errors, misalignment and nonlinearity; the latter contains temperature effect and signal drifting. Subsequently, the linearity calibration is used to modify the deterministic error and the …


Fast Block Motion Estimation With Edge Alignment On H.264 Video Coding, Chi-Han Chuang, Chien-Hua Su, Shyi-Chyi Cheng Dec 2010

Fast Block Motion Estimation With Edge Alignment On H.264 Video Coding, Chi-Han Chuang, Chien-Hua Su, Shyi-Chyi Cheng

Journal of Marine Science and Technology

This paper presents a novel block matching scheme with edge alignment strategy on H.264 video coding, which uses multiple references and multiple block sizes for motion estimation in order to improve the rate-distortion performance. In H.264, the computational complexity is linearly dependent on the number of allowed reference frames and block sizes using the full exhaustive search. Many fast block-matching algorithms reduce the computational complexity of motion estimation by carefully designing the search patterns with different shapes or sizes which have significant impact on the search speed and distortion performance. However, the search speed and the distortion performance conflict often …


The Performance Of Indium Tin Oxide Films Deposited On Plastic Substrate Applied For Solar-Cell Buoy, Chien-Kun Wang, Jyh-Jier Ho, Sung-Jen Nien, Yuang-Tung Cheng, William Lee, Chih-Chiang Lu, Bao-Shun Yau, Hsing-Wang Tsai, Chung-Cheng Chang Dec 2010

The Performance Of Indium Tin Oxide Films Deposited On Plastic Substrate Applied For Solar-Cell Buoy, Chien-Kun Wang, Jyh-Jier Ho, Sung-Jen Nien, Yuang-Tung Cheng, William Lee, Chih-Chiang Lu, Bao-Shun Yau, Hsing-Wang Tsai, Chung-Cheng Chang

Journal of Marine Science and Technology

In this paper, we report the indium tin oxide (ITO) films deposited on the polyethyene terephthalate (PET) substrate, which surface is treated with detergent solution. The ITO films are deposited on room temperature by direct current (DC) magnetron sputtering from a ceramic target of a 90% In-10% Sn alloy. The deposited opto-electric ITO films on PET with detergent treatment are 83.4% average visible transparency, and 5.8 × 10-4 Ω-cm resistivity, respectively. And then, we use the spin coating to form the polymer solar cell. Under optimal conditions of surface treatment and film deposition, the experimental result shows 2.12% of the …


Signal Subspace Transformation For Direction-Of-Arrival Estimation Of Wideband Sources In Near Field, Lena Chang Dec 2010

Signal Subspace Transformation For Direction-Of-Arrival Estimation Of Wideband Sources In Near Field, Lena Chang

Journal of Marine Science and Technology

A novel adaptive signal subspace transformation for direction-of-arrival (DOA) estimation of wideband sources in the near-field is proposed in this paper. The method is composed of two transformations: signal subspace focusing (SSF) and far-field transformation (FFT). SSF aligns the signal subspaces for different frequencies in the bandwidth of the sources based on focusing matrices. FFT transforms the near-field steering vector to be the far-field steering vector with same direction-of-arrival (DOA) allocation. By the way, we simplify the location estimation of wideband sources in the near-field to be narrowband sources in the far field. The proposed method can track the DOAs …


The Study On The Asymptotic Profile And The Flow Patterns In Front Of A Long Bubble Through A Circular Tube, Cheng-Hsing Hsu, Chia-Chuan Kuo, Ching-Chuan Chang, Kuang-Yuan Kung Dec 2010

The Study On The Asymptotic Profile And The Flow Patterns In Front Of A Long Bubble Through A Circular Tube, Cheng-Hsing Hsu, Chia-Chuan Kuo, Ching-Chuan Chang, Kuang-Yuan Kung

Journal of Marine Science and Technology

Department of Civil Engineering, Army Academy, Chung-Li, Taoyuang, Taiwan, R.O.C


Sidescan Sonar Image Processing:Correcting Brightness Variation And Patching Gaps, Yet-Chung Chang, Shu-Kun Hsu, Ching-Hui Tsai Dec 2010

Sidescan Sonar Image Processing:Correcting Brightness Variation And Patching Gaps, Yet-Chung Chang, Shu-Kun Hsu, Ching-Hui Tsai

Journal of Marine Science and Technology

Sidescan sonar data are typically presented as gray level images. However, sidescan images often show striking variations in brightness. These variations, caused by the sonar beam pattern and the constantly changing attitude of the towfish, make the images difficult to read as pictures of the seabed. This reduces the utility of the images for marine geologists. In this paper, the effects of the sonar beam pattern across the swath are corrected using a normalization process based on the average signal intensity for each grazing angle. Noise along the track, which is generally caused by changes in the attitude of the …


The Sensitivity Analysis Of A Mems Microphone With Different Membrane Diameters, Cheng-Ta Yang Dec 2010

The Sensitivity Analysis Of A Mems Microphone With Different Membrane Diameters, Cheng-Ta Yang

Journal of Marine Science and Technology

In MEMS capacitive microphone design, it is very critical to get highest yielding rate and sensitivity as the two major factors dominate structure design of microphone. The centralpost MEMS microphone is introduced in this paper to differentiate from traditional fixed membrane boundary microphone since the construction is simple and only few masks are required in the process so that the yielding can be greatly enhanced. Thus, it is necessary to find the relationship between the sensitivity and dimension of the diameter of the membrane. The main research steps described in this paper include using CoventorWarer to develop one analysis model …


An Algorithm For Predicting Attitudes Of Floating Bodies With Arbitrary Configurations In Liquids, Jiann-Lin Chen, Chun-I Chen, Li-Ming Chu Dec 2010

An Algorithm For Predicting Attitudes Of Floating Bodies With Arbitrary Configurations In Liquids, Jiann-Lin Chen, Chun-I Chen, Li-Ming Chu

Journal of Marine Science and Technology

A robust and efficient algorithm is proposed to quasiunsteadily predict attitudes of floating bodies with arbitrary configurations. Numerical techniques for accuracy and computing time saving are addressed. A floating cylinder was modeled as a benchmark, by theoretical and experimental approaches, to validate the developed program. Attitudes of two kinds of floating bodies, which are a body composed of multiple objects and a submarine-like submersible, were simulated to show the feasibility of the present algorithm. Interestingly, the simulated results of a slender body, such as a cylinder or a submersible, show that the attitude variation is very sensitive to the longitudinal …


Improving The Emulsion Stability Of Sponge Cake By The Addition Of ?-Polyglutamic Acid, Yung-Shin Shyu, Wen-Chieh Sung Dec 2010

Improving The Emulsion Stability Of Sponge Cake By The Addition Of ?-Polyglutamic Acid, Yung-Shin Shyu, Wen-Chieh Sung

Journal of Marine Science and Technology

The batter properties of sponge cake with the addition of γ-polyglutamic acid (PGA) at different levels (0.05, 0.1, 0.5 gkg-1, w/w) was evaluated. The viscosity, emulsion stability and foam stability increased at the addition of 0.5 gkg-1 PGA level. PGA caused significant declines in the differential scanning calorimetry (DSC) enthalpy, onset and peak temperatures of ice-melting transition of sponge cake. Sponge cakes manufactured with 0.5 gkg-1 PGA addition were in general lighter on crumb color and white index than the control. Scanning electron microscopy showed that sponge cake with the addition of 0.1 and 0.5 gkg-1 PGA exhibited microstructures having …


Research On Nafion/Sio_2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu Nov 2010

Research On Nafion/Sio_2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu

Journal of Electrochemistry

The Nafion117/SiO2 composite membrane was prepared by sol-gel method.The results showed that,during composite membrane preparation process,the ratio of MeOH and TEOS did not affect the penetration rate of VO2+ basically,however,the lowest permeability of 427×10-9cm2/s in the membrane was achieved while hydrolysis time was 10 min and natural drying for 24 h after hydrolysis,which reduced by 52 times than that in Nafion117 membrane.The SEM tests proved that SiO2 grains grew bigger in the composite membrane during the natural drying,and most of the holes in Nafion117 were filled.Single cell test showed the battery power efficiency was improved by 2.7 %.


Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang Nov 2010

Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang

Journal of Electrochemistry

The PbO2 anodes were prepared on platinum from fluoroborate media and its doped solutions by electrodeposition technique.Elecchemical and pysicochemical properties of these PbO2 films were studied by cyclic voltammetry methods,XRD and SEM.The results showed that the presence of BF4-increased PbO2 electrodeposition rate;the prepared lead dioxide consisted of β-PbO2;the preferential orientation of crystals and surface morphology were affected a lot by doping F-and Fe3+.The FB/F-Fe-PbO2 electrode exhibited regular-shaped layers with compact morphology.Furthermore,increasing current density also change the preferential orientation of PbO2 crystals.


Photoelectrochemical Properties Of N,S,And Cl Modified Nano Tio_2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du Nov 2010

Photoelectrochemical Properties Of N,S,And Cl Modified Nano Tio_2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du

Journal of Electrochemistry

The nitrogen(N),sulfur(S) and chlorine(Cl) modified nano TiO2 thin films were prepared by adding Ti(O-n-Bu)4 as the precursor into concentrated HNO3,H2SO4 and HCl Solutions,respectively,on different substrates in a sol-gel process.The photoelectrochemical performances of N,S and Cl modified nano TiO2 thin films have been studied by UV-vis(DRS),photocurrent curves,EIS and OCP-time curves.N-modified TiO2 nano films show better surface structure,which helps to improve the quantum efficiency of nano TiO2 thin films.


Hydrothermal Reduction Synthesis Of Lifepo_4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen Nov 2010

Hydrothermal Reduction Synthesis Of Lifepo_4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen

Journal of Electrochemistry

The cathode materials of LiFePO4 were prepared via a hydrothermal reduction method using FeCl3 as Fe source and iron as a reducing agent.The results showed that ferric salt could be reduced to ferrous salt completely under the hydrothermal condition and pure-phase LiFePO4 was obtained based on the test results of XRD and FTIR.Carbon-coated LiFePO4 was synthesized by pyrolysisng glucose at high temperature.The morphologies of pure LiFePO4 displayed cluster-like while the LiFePO4/C displayed sphere-like particles.The electrochemical test showed that the LiFePO4/C had good rate performance,while LiFePO4 delivered much lower discharge capacity.


The Sol-Gel Synthesis And Electrochemical Performance Of Li_3v_2(Po_4)_3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai Nov 2010

The Sol-Gel Synthesis And Electrochemical Performance Of Li_3v_2(Po_4)_3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai

Journal of Electrochemistry

Li3V2(PO4)3/C was synthesized by sol-gel method with citric acid as chelate and C sources.Physical and electrochemical performances of as-prepared materials were characterized through XRD,SEM and galvanostatic charge-discharge tests,etc.The results showed that products produced by calcining at 800 ℃ for 12 h had a single phase crystal structure and relatively small particle sizes with uniform distribution.At 0.1 C,0.5 C and 1 C,the initial specific discharge capacities were 153.0,143.1 and 130.6 mAh·g-1,respectively,and capacity efficiencies were 93.1%,85.4% and 77.3% after 50 cycles,respectively.Charge efficiencies were all above 80% and discharge voltages were higher.


Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang Nov 2010

Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang

Journal of Electrochemistry

The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile(MeCN),propylene carbonate(PC) and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate(TBAPF6)/MeCN or TBAPF6/PC electrolyte.However,the CV curves in 0.1 mol·L-1 TBAPF6/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L-1 TBAPF6/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak of O2-almost disappeared as compared to that of the former electrolytes.The possible …


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 Nov 2010

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 …


Remote Sensing And Geographical Information System To Identify Drought Potency, Puguh Dwi Raharjo Nov 2010

Remote Sensing And Geographical Information System To Identify Drought Potency, Puguh Dwi Raharjo

Makara Journal of Technology

Remote Sensing and Geographical Information System to Identify Drought Potency. Kebumen regency was drought in year 2008, community clean water shortages and irrigation water following a decline in water resources. The use of remote sensing data and GIS can be used to identify the potential for drought-prone areas. Transformation of Landsat TM satellite imagery to obtain the brightness index, wetness index and vegetation index used to determine surface conditions in relation to drought. Brightness index and wetness index derived from the tasseled cap modifications, while the vegetation index derived from normalized difference vegetation index (NDVI) values. Other parameters such as …


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 Nov 2010

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 …


An Empirical Model For Build-Up Of Sodium And Calcium Ions In Small Scale Reverse Osmosis, Subriyer Nasir Nov 2010

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 …


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 Nov 2010

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 …


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 Nov 2010

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 …


The Stability Characteristics Of Sandbag Submerged Breakwater, Ferry Fatnanta, Widi Agoes Pratikto, Haryo Dwito Armono, Wahyudi Citrosiswoyo Nov 2010

The Stability Characteristics Of Sandbag Submerged Breakwater, Ferry Fatnanta, Widi Agoes Pratikto, Haryo Dwito Armono, Wahyudi Citrosiswoyo

Makara Journal of Technology

The Stability Characteristics of Sandbag Submerged Breakwater. Breakwater is one of coastal structures to overcome problems of abrasion. Due to difficulties in obtaining rock material at the coastal area. The using of sandbags as a breakwater provides advantages in utilizing local materials. A Sandbag has a smooth surface, so the internal shear forces are relatively small. According to these phenomena, the research for parameters that are expected to affect the stability of the sand bags. These parameters are a slope, shape and formation of sand bags. This experimental research conducted in two dimensional physical model and took place on the …


Static Hand Gesture Recognition Of Indonesian Sign Language System Based On Backpropagation Neural Networks, Farida Asriani, Hesti Susilawati Nov 2010

Static Hand Gesture Recognition Of Indonesian Sign Language System Based On Backpropagation Neural Networks, Farida Asriani, Hesti Susilawati

Makara Journal of Technology

Static Hand Gesture Recognition of Indonesian Sign Language System Based on Backpropagation Neural Networks. The main objective of this research is to perform pattern recognition of static hand gesture in Indonesian sign language. Basically, pattern recognition of static hand gesture in the form of image had three phases include: 1) segmentation of the image that will be recognizable form of the hands and face, 2) feature extraction and 3) pattern classification. In this research, we used images data of 15 classes of words static. Segmentation is performed using HSV with a threshold filter based on skin color. Feature extraction performed …


The Effect Of Enzymatic Hydrolysis On The Properties Of Protein Hydrolysate From Paddy Mushroom, Niken Widya Palupi, Wiwik Siti Windrati, Tamtarini Tamtarini Nov 2010

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 …


Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo Nov 2010

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 …


Separation Study Of Titanomagnetite Fe3-Xtixo4 From Natural Sand At Indramayu, West Java, Sunaryo Sunaryo, Iwan Sugihartono Nov 2010

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, …


Concept Design And Testing Of Multi-Nozzle Water Mist Fire Suppression System, Danardono A. Sumarsono, Yulianto S. Nugroho, Mariance Mariance, I Gede Wahyu W. Ariasa Nov 2010

Concept Design And Testing Of Multi-Nozzle Water Mist Fire Suppression System, Danardono A. Sumarsono, Yulianto S. Nugroho, Mariance Mariance, I Gede Wahyu W. Ariasa

Makara Journal of Technology

In this work a flexible design of multi-nozzle arrangement of water mist fire suppression system was studied. The source of fire was a 65 mm diameter cooking oil fire. An investigation on the impact of nozzle arrangement on the temperature profile of fires was conducted. The occurance of oil splash due to the application of water mist was also studied. The water mist systems developed in the present work can effectively extinguish cooking oil fires and prevented them from re-ignition. The spray angle, discharge pressure, and water flow rate were important factors to determine the effectiveness of water mist in …


Development Of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach, Bagiyo Suwasono, Sjarief Widjaja, Achmad Zubaydi, Zaed Yuliadi, I Nyoman Budiantara Nov 2010

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 …


Wimax Implementation As Existing Hotspot Network Backhaul In Jakarta, Djamhari Sirat, Muhamad Asvial, Luther B. Marpaung Nov 2010

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 …


High Pressure Adsorption Isotherm Of Co2 On Activated Carbon Using Volumetric Method, Awaludin Martin, Bambang Suryawan, Muhammad Idrus Alhamid, Nasruddin Nasruddin Nov 2010

High Pressure Adsorption Isotherm Of Co2 On Activated Carbon Using Volumetric Method, Awaludin Martin, Bambang Suryawan, Muhammad Idrus Alhamid, Nasruddin Nasruddin

Makara Journal of Technology

High Pressure Adsorption Isotherm of CO2 on Activated Carbon using Volumetric Method. Adsorption system is ones of the most effective methods for CO2 separating with other substances that produced from the burning of fossil fuels. In the design for that application, beside of characteristics of porous material (adsorbent) data, CO2 adsorption data on the adsorbent (kinetic and thermodynamic) are also needed. The aim of this research is resulting isothermal adsorption data at pressures up to 3.5 MPa by indirect methods (volumetric method) at isothermal temperature of 300, 308, 318 and 338 K. Adsorbent that used in this research is activated …