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Articles 391 - 420 of 705

Full-Text Articles in Electrical and Electronics

Lateral Load Resistance Of Laminated Veneer Lumber Sengonwooden Joints With Wooden Dowels, Niken Palaeowati, Ali Awaludin, Suprapto Siswosukarto Dec 2014

Lateral Load Resistance Of Laminated Veneer Lumber Sengonwooden Joints With Wooden Dowels, Niken Palaeowati, Ali Awaludin, Suprapto Siswosukarto

Makara Journal of Technology

Analytical models for wooden-doweled joints need to be developed. The objective of this research is to determine whether the strength of wooden-doweled joints can be well predicted by equations developed for steel-doweled joints. In this experiment, various connection parameters, such as dowel diameter, species of the wooden dowel, and angle of joints, are studied. The joint specimens are loaded in a quasi-static state with four replications each. A5% offset diameter method is used to determine the lateral load resistance of the tested joints, while the predictions are evaluated by equations given in Indonesian National Standard (SNI) 7973-2013 and the European …

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Make Or Buy Analysis Model Based On Tolerance Design To Minimize Manufacturing Cost And Quality Loss, Cucuk Nur Rosyidi, Reza Rizkichani Akbar, Wakhid Ahmad Jauhari Aug 2014

Make Or Buy Analysis Model Based On Tolerance Design To Minimize Manufacturing Cost And Quality Loss, Cucuk Nur Rosyidi, Reza Rizkichani Akbar, Wakhid Ahmad Jauhari

Makara Journal of Technology

In a manufacturing company, manufacturing costs, or component prices, and tolerance will affect the price and the quality of a product. Companies must produce high-quality products with low manufacturing costs in order to keep their products competitive in the market; however, it is difficult to produce a high-quality product with a low manufacturing cost. Companies have difficulties in determining the components to be produced using their own manufacturing facilities (make) or outsourced to their suppliers (buy). Hence, a make or buy analysis is needed to minimize the manufacturing costs and quality loss and to determine the optimum alternative regarding make …

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Observation Of Tunneling Effects In Lateral Nanowire Pn Junctions, Sri Purwiyanti, Arief Udhiarto, Daniel Moraru, Takeshi Mizuno, Djoko Hartanto, Michiharu Tabe Aug 2014

Observation Of Tunneling Effects In Lateral Nanowire Pn Junctions, Sri Purwiyanti, Arief Udhiarto, Daniel Moraru, Takeshi Mizuno, Djoko Hartanto, Michiharu Tabe

Makara Journal of Technology

As electronic device dimensions are continuously reduced, applied bias conditions significantly change and the transport mechanisms must be reconsidered. Tunneling devices are promising for scaled-down electronics because of expected high-speed operation and relatively low bias. In this work, we investigated the tunneling features in silicon-oninsulator lateral nanowire pn junction and pin junction devices. By controlling the substrate voltage, tunneling features can be observed in the electrical characteristics. We found that the minimum substrate voltage required for tunneling to occur in pn junctions is higher as compared with pin junctions. The main cause of these effects relies in the difference between …

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Digestibility Of Betung Bamboo Fiber Following Fungal Pretreatment, Widya Fatriasari, Wasrin Syafii, Nyoman J. Wistara, Khaswar Syamsu, Bambang Prasetya Aug 2014

Digestibility Of Betung Bamboo Fiber Following Fungal Pretreatment, Widya Fatriasari, Wasrin Syafii, Nyoman J. Wistara, Khaswar Syamsu, Bambang Prasetya

Makara Journal of Technology

This research evaluated the effect of fungal pretreatment of betung bamboo fibers and enzymatic- and microwaveassisted hydrolysis on the reducing sugar yield. The enzymatic hydrolysis of the pretreated biomass was carried out with cellulase and 10 and 20 FPU/g of substrate in a shaking incubator at 50 °C and 150 rpm for 48 h. The sulfuric acid concentration used in the microwave-assisted acid hydrolysis was 1.0, 2.5, and 5%, either with or without the addition of activated carbon. Microwave irradiation (330 Watt) was applied for 5–12.5 min. The yield of reducing sugar was better with the microwave-assisted acid hydrolysis, and …

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Argon Ion Irradiation Effect On The Magnetic Properties Of Fe-Al2o3 Nano Granular Film, Setyo Purwanto, Isao Sakamoto Aug 2014

Argon Ion Irradiation Effect On The Magnetic Properties Of Fe-Al2o3 Nano Granular Film, Setyo Purwanto, Isao Sakamoto

Makara Journal of Technology

We studied the effect of Argon (Ar) ion irradiation on Fe-Al2O3 nanogranular thin film. X-ray diffraction (XRD) patterns show that the ion dose might promote the growth of the Fe2O3 phase from an amorphous phase to a crystalline phase. The magnetic and magnetoresistance properties were investigated using a vibrating sample magnetometer (VSM) and a four point probe (FPP). The results suggest that percolation concentration occurred at the 0.55 Fe volume fraction and with a maximum magnetoresistance (MR) ratio of 3%. The present MR ratio was lower than that of previous results, which might be related to the existence of the …

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Adjustable Resonance Frequency Of Rf-Mems Capacitor By Using Comb- Drive Actuators: A Design Approaches, Agus Santoso Tamsir, Sandy Tannu Wijaya, Dato’ Burhanuddin Yeop Majlis Aug 2014

Adjustable Resonance Frequency Of Rf-Mems Capacitor By Using Comb- Drive Actuators: A Design Approaches, Agus Santoso Tamsir, Sandy Tannu Wijaya, Dato’ Burhanuddin Yeop Majlis

Makara Journal of Technology

The needs of smaller size RF varactor is a must today, and MEMS comes to be the potential one. In this paper we proposed an adjustable resonance RF-MEMS varactor by using comb-drive actuators placing in each side of the square movable plate. In our preliminary simulation, we found that the device can work properly but some constraints comes such as the dominancies of harmonic resonance frequencies that influences into the nominal capacitances. Therefore for the next step of development we have to find out the window of the structural dimension for a certain spans and a certain operating frequencies.

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Properties Of Lignin From Oil Palm Empty Fruit Bunch And Its Application For Plywood Adhesive, Lucky Risanto, Euis Hermiati, Yanni Sudiyani Aug 2014

Properties Of Lignin From Oil Palm Empty Fruit Bunch And Its Application For Plywood Adhesive, Lucky Risanto, Euis Hermiati, Yanni Sudiyani

Makara Journal of Technology

Lignin from lignocellulosic biomass is a potential biopolymer for wood adhesive. The aims of this study were to characterize lignin isolated from the black liquor of oil palm empty fruit bunch fiber pretreated with steam explosion in alkaline conditions and to examine the bond quality of aqueous polymer isocyanate (API) adhesive prepared from lignin, natural rubber latex (NRL), and polyvinyl alcohol (PVA) as base polymers with isocyanate crosslinkers. Lignin was precipitated from the black liquor by adding hydrochloric acid; then the precipitate was separated by filtration, thoroughly washed with water up to pH 2 and pH 5, and dried. The …

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Electron Emission Characteristics Of Multi-Gated Field Emitters, Hidenori Mimura, Yoichiro Neo, Toru Aoki, Tomoya Yoshida, Masayoshi Nagao Aug 2014

Electron Emission Characteristics Of Multi-Gated Field Emitters, Hidenori Mimura, Yoichiro Neo, Toru Aoki, Tomoya Yoshida, Masayoshi Nagao

Makara Journal of Technology

We have developed a multi-gated field emitter (FE) such as a quadruple-gated FE with a three-stacked electrode lens and a quintuple-gated FE with a four-stacked electrode lens. Both the FEs can focus the electron beam. However, the quintuple-gated FE has a stronger electron convergence than the quadruple-gated FE, and a beam crossover is clearly observed for the quintuple-gated FE.

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The Gaussian Orthogonal Laplacianfaces Modelling In Feature Space For Facial Image Recognition, Arif Muntasa Aug 2014

The Gaussian Orthogonal Laplacianfaces Modelling In Feature Space For Facial Image Recognition, Arif Muntasa

Makara Journal of Technology

Dimensionality reduction based on appearance has been interesting issue on the face image research fields. Eigenface and Fisherface are linear techniques based on full spectral features, for both Eigenface and Fisherface produce global manifold structure. Inability of them in yielding local manifold structure have been solved by Laplacianfaces and further improved by Orthogonal Laplacianfaces, so it can yield orthogonal feature vectors. However, they have also a weakness, when training set samples have non-linear distribution. To overcome this weakness, feature extraction through data mapping from input to feature space using Gaussian kernel function is proposed. To avoid singularity, the Eigenface decomposition …

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Series-Interconnected Plastic Dye-Sensitized Solar Cells Prepared By Low- Temperature Binder-Free Titania Paste, Erlyta Septa Rosa, Lia Muliani, Shobih Shobih, Jojo Hidayat, Brian Yuliarto Aug 2014

Series-Interconnected Plastic Dye-Sensitized Solar Cells Prepared By Low- Temperature Binder-Free Titania Paste, Erlyta Septa Rosa, Lia Muliani, Shobih Shobih, Jojo Hidayat, Brian Yuliarto

Makara Journal of Technology

The aim of this research is to study dye-sensitized solar cells (DSSC). This was implemented on a flexible polyethylene terephthalate (PET) substrate using a mixture of transparent and scattered mesoporous anatase-titania as the electron transport layer for the photoelectrode. This mixture of anatase titania performed a dual function of light scattering and efficient dye absorption. In this study, a porous nano-TiO2 film was prepared on indium tin oxide (ITO) coated polyethylene terephthalate (PET) by using a binder-free titania paste; on it, a DSSC was fabricated. The paste which contained a mixture of TiO2 nanoparticles, acid chloride, and ethanol was printed …

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Fundamental Design Principles Of Novel Mems Based "Landau" Switches, Sensors, And Actuators : Role Of Electrode Geometry And Operation Regime, Ankit Jain Jul 2014

Fundamental Design Principles Of Novel Mems Based "Landau" Switches, Sensors, And Actuators : Role Of Electrode Geometry And Operation Regime, Ankit Jain

Open Access Dissertations

Microelectromechanical systems (MEMS) are considered as potential candidates for "More-Moore" and "More-than-Moore" applications due to their versatile use as sensors, switches, and actuators. Examples include accelerometers for sensing, RF-MEMS capacitive switches in communication, suspended-gate (SG) FETs in computation, and deformable mirrors in optics. In spite of the wide range of applications of MEMS in diverse fields, one of the major challenges for MEMS is their instability. Instability divides the operation into stable and unstable regimes and poses fundamental challenges for several applications. For example: Tuning range of deformable mirrors is fundamentally limited by pull-in instability, RF-MEMS capacitive switches suffer from …

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St. Jude Medical - R&D Robot For Sensor Testing, Andrew Chanul Kim, Stanley Logan Laszczyk, Edgar Nava, Nathan Gall Jun 2014

St. Jude Medical - R&D Robot For Sensor Testing, Andrew Chanul Kim, Stanley Logan Laszczyk, Edgar Nava, Nathan Gall

Electrical Engineering

No abstract provided.

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Mobile Solar Pv Trainer, Matthew Myers, Matthew Clause, Lawrence Smith Jun 2014

Mobile Solar Pv Trainer, Matthew Myers, Matthew Clause, Lawrence Smith

Mechanical Engineering

The aim of the Mobile Solar PV Trainer Project was to design, construct and test a versatile and robust laboratory training rig for the Cal Poly Electrical Engineering department. This project was inspired by the desire of one or more California Polytechnic State University electrical engineering professors to add laboratory components to two established upper division electrical engineering courses in photovoltaic panels and solar power. This report contains a detailed description of the trainer’s desired specifications, our ideation process, a thorough description of the selected trainer design including part drawings, assembly documentation and a bill of materials as well as …

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Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique, Agung Budipriyanto, Priyo Suprobo Apr 2014

Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique, Agung Budipriyanto, Priyo Suprobo

Makara Journal of Technology

Identifying dynamic characteristics of civil engineering structures is still a challenging task. It intends to assess behavior of the structures under time-dependent loads. This paper discusses a methodology suitable for identifying the characteristics of multi-story buildings using only their measured response under earthquake ground excitations. Appropriateness of technique used for structural identification was corroborated through coherence of the structure’s responses. The methodology was applied for identifying the characteristics of 14-story and 20-story office buildings located in a high seismic region. Responses of these two buildings recorded during three different seismic ground motions were investigated. The buildings’ response spectral densities and …

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Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method, Faisal Mahmuddin, Masashi Kashiwagi Apr 2014

Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method, Faisal Mahmuddin, Masashi Kashiwagi

Makara Journal of Technology

In the previous study, the optimal performance of a two-dimensional (2D) floating breakwater shape was obtained. The performance of this shape was also confirmed with a model experiment in a towing tank. Moreover, the shape’s performance in three dimensions (3D) was investigated in a subsequent study. However, to predict the shape’s performance in a real application more accurately, the shape’s characteristics in oblique waves must also be evaluated. In this study, the performance and characteristics of the model (hydrodynamic forces, body motions, wave elevations, and drift forces) are computed using a higher-order boundary element method (HOBEM). The HOBEM, which is …

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Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol, Flora Elvistia Firdaus Apr 2014

Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol, Flora Elvistia Firdaus

Makara Journal of Technology

The use of vegetable oils on replacing petroleum has attracted attention of many researchers. The chemical structure of vegetable oils are different from petrochemicals, so the structure of soybean oil has to be chemically modified through its unsaturated fatty acid chain in triglyceride. A two step process was conducted for the preparation of soy-polyol in designated temperatures; 50 °C, 60 °C, and 70 °C. Ethylene glycol (EG) as co-reagent was taking part in soy-polyol synthesis, and the soy-polyol was used as a sole polyol for polyurethane synthesis. Referred to the previous study, the existence of EG in polyurethane synthesis can …

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Performances Of Free-Space Optical Communication System Over Strong Turbulence, Ucuk Darusalam, Purnomo Sidi Priambodo, Harry Sudibyo, Eko Tjipto Rahardjo Apr 2014

Performances Of Free-Space Optical Communication System Over Strong Turbulence, Ucuk Darusalam, Purnomo Sidi Priambodo, Harry Sudibyo, Eko Tjipto Rahardjo

Makara Journal of Technology

We report an experimental of free-space optical communication (FSOC) system that use tube propagation simulator (TPS) as the turbulence medium. The FSOC system use wavelength of 1550 nm at the rate transmission of 1000 Mbps and amplified with EDFA at the output of +23 dBm. Index structure of 10-15–10-13 as the representation of atmosphere index turbulences are used for simulation of intensity distribution model or scintillation. The simulation use gammagamma and K model as well. The beam wave propagation models used in simulation are plane wave, spherical wave and Gaussian wave. Spherical wave achieves highest performance via gamma-gamma in strong …

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Preparations Of Nanostructured Silicide Bundles And Oxide Arrays, Hirokazu Tatsuoka, Wen Li, Erchao Meng, Daisuke Ishikwa, Kaito Nakane, Shingo Oda, Tomoji Matsushita, Natsuki Kurebayashi Apr 2014

Preparations Of Nanostructured Silicide Bundles And Oxide Arrays, Hirokazu Tatsuoka, Wen Li, Erchao Meng, Daisuke Ishikwa, Kaito Nakane, Shingo Oda, Tomoji Matsushita, Natsuki Kurebayashi

Makara Journal of Technology

A variety of nanostructured silicide bundles and oxide nanowire arrays with abundant, non-toxic materials we are prepared. The CrSi2 nanowire and Mg2Si/MgO composite nanowire bundles were synthesized using a Si substrate and a SiOx nanofiber bundle, respectively. The hexagonal MoSi2 nanosheet bundles were also synthesized using a MoS2 layered material as a template. In addition, ZnO, CuO/Cu2O and a-Fe2O3 nanowire arrays were prepared on semiconductor or metallic substrates. The growth phenomena and the structural properties of the nanostructured materials awere investigated. In addition, the preparations of axial and radial nanowire structures weare examined.

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Bioethanol Production From Iles-Iles And Sorghum Starch As Raw Materials (Effect Of Cacl 2 Addition And Saccharification Time), Kusmiyati Kusmiyati, Ali Mahmudi Apr 2014

Bioethanol Production From Iles-Iles And Sorghum Starch As Raw Materials (Effect Of Cacl 2 Addition And Saccharification Time), Kusmiyati Kusmiyati, Ali Mahmudi

Makara Journal of Technology

Bioethanol produced from agricultural sources is one alternative energy that has been developed to substitute for petroleum. However, the use of food sources such as corn and cassava to produce bioethanol still face obstacles that lead to the scarcity of food and an increase in food prices. The aim of this study was to produce bioethanol from sorghum and iles-iles, which are not used by humans as food, especially in Indonesia. For both materials, the variables studied were saccharification time (4, 8, 24, and 48 h) and concentration of CaCl2 added to the liquefaction slurry (0, 100, 200, 300, and …

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The Effect Of Zephyr Layer Orientation On Zephyrboard Made From Oil Palm Petiole, Lusita Wardani, Muhamad Yusram Massijaya, Yusuf Sudo Hadi, I Wayan Darmawan Apr 2014

The Effect Of Zephyr Layer Orientation On Zephyrboard Made From Oil Palm Petiole, Lusita Wardani, Muhamad Yusram Massijaya, Yusuf Sudo Hadi, I Wayan Darmawan

Makara Journal of Technology

It is very important to utilize oil palm petiole for the production of zephyr boards. This study aimed to analyze the effect of layer orientation on zephyr board quality. Zephyr boards were made with three coating patterns (A = cross perpendicular, B= combine A and C, and C= paralell) and five zephyr layers using urea formaldehyde adhesive. They were pressed for 20 min at a pressure of 25 kgf/cm² and a temperature 120 ºC, to a target density of 0.80 g/cm³ and a size of 300 mm X 300 mm X 12 mm. Our results showed that the physical and …

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Analysis Of Power Efficiency Of A Direct-Driven Locally Fabricated Permanent Magnet Ac Generator For Small-Scale Wind Power Applications In Tanzania, Mussa Iddi Mgwatu Dr. Dec 2013

Analysis Of Power Efficiency Of A Direct-Driven Locally Fabricated Permanent Magnet Ac Generator For Small-Scale Wind Power Applications In Tanzania, Mussa Iddi Mgwatu Dr.

Tanzania Journal of Engineering and Technology (TJET)

The use of direct-driven permanent magnet alternating current (AC) generators offers the opportunity to reduced costs and increased system efficiency. This type of generator could be the best alternative for rural population whom are not connected to the national grid. To improve the design and efficiency of locally fabricated generators, it is imperative to characterize both their mechanical and electrical parameters. This paper presents the analysis of power efficiency of the synchronous permanent AC generator locally fabricated in Tanzania. In this case, load resistance and rotational speed are characterized using designed experiment. The output current and voltage of the generator …

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Mems Cantilever Sensor For Thz Photoacoustic Chemical Sensing And Spectroscopy, Nathan E. Glauvitz Dec 2013

Mems Cantilever Sensor For Thz Photoacoustic Chemical Sensing And Spectroscopy, Nathan E. Glauvitz

Theses and Dissertations

Sensitive Microelectromechanical System (MEMS) cantilever designs were modeled, fabricated, and tested to measure the photoacoustic (PA) response of gasses to terahertz (THz) radiation. Surface and bulk micromachining technologies were employed to create the extremely sensitive devices that could detect very small changes in pressure. Fabricated devices were then tested in a custom made THz PA vacuum test chamber where the cantilever deflections caused by the photoacoustic effect were measured with a laser interferometer and iris beam clipped methods. The sensitive cantilever designs achieved a normalized noise equivalent absorption coefficient of 2.83x10-10 cm-1 W Hz-1/2 using a 25 …

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Synthesis Of Tungsten Oxide Nanowires Onto Ito Glass Using T-Cvd, Tomy Abuzairi, Bohr-Ran Huang, Tzu-Ching Lin Dec 2013

Synthesis Of Tungsten Oxide Nanowires Onto Ito Glass Using T-Cvd, Tomy Abuzairi, Bohr-Ran Huang, Tzu-Ching Lin

Makara Journal of Technology

Tungsten oxide is an n-type semiconductor with interesting physical and chemical properties that make it suitable for various technological applications. Tungsten oxide nanowires were synthesized not only at low temperature but also without the use of any catalysts. The tungsten oxide nanowires were synthesized at 550 °C with tungsten layers onto the ITO glass using thermal chemical vapor deposition (T-CVD). The SEM image shows that the tungsten oxide nanowires are effectively grown with the 200 nm tungsten film. The Raman spectra shoulder at ~690 cm-1 proves the synthesized of tungsten oxide nanowires.

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Radiation Characteristics Of A Planar Strip Dipole Antenna And A Slot Dipole Antenna For Thz Applications, Catur Apriono, Eko Tjipto Rahardjo Dec 2013

Radiation Characteristics Of A Planar Strip Dipole Antenna And A Slot Dipole Antenna For Thz Applications, Catur Apriono, Eko Tjipto Rahardjo

Makara Journal of Technology

The development of a THz system often requires a device that is used to radiate or detect THz waves. One way to fulfill this requirement is to use an antenna. Therefore, we need to consider the radiation characteristics of an antenna working in the THz region. In this paper, we present simulation study of two dipole antennas, i.e. a planar strip dipole antenna and a slot dipole antenna. The simulation results show that a planar strip dipole antenna has a better radiation efficiency (more than 95%) compared to the slot dipole. It also shows that an efficiency of more than …

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The Effect Of Pressing Temperature And Time On The Quality Of Particle Board Made From Jatropha Fruit Hulls Treated In Acidic Condition, Apri Heri Iswanto, Fauzi Febrianto, Yusuf Sudo Hadi, Surdiding Ruhendi, Dede Hermawan Dec 2013

The Effect Of Pressing Temperature And Time On The Quality Of Particle Board Made From Jatropha Fruit Hulls Treated In Acidic Condition, Apri Heri Iswanto, Fauzi Febrianto, Yusuf Sudo Hadi, Surdiding Ruhendi, Dede Hermawan

Makara Journal of Technology

The high of pH of jatropha fruit hulls causes the negative properties of particleboard made from this material. Adjusting the particle acidity and pressing conditions (temperature and time) is among the technical modifications available to improve this particleboard’s properties. Particle acidity has been adjusted in a previous research project, and immersing the particles in acetic acid was found to be the best treatment in this preliminary research. In order to improve the particleboard’s properties, an experiment was conducted to determine the best pressing temperature and time. The objective of the research was to evaluate the influence of pressing temperature and …

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Microgrid Development Using A Grid Tie Inverter, Hartono Budi Santoso, Budiyanto Budiyanto Dec 2013

Microgrid Development Using A Grid Tie Inverter, Hartono Budi Santoso, Budiyanto Budiyanto

Makara Journal of Technology

The use of renewable energy sources (RES), especially photovoltaic (PV), to meet the demand of electrical energy has been getting a great deal of attention as an alternative solution to electrical energy deficit problems. RES are being applied in power systems in a variety of configurations including microgrid systems. One of the characteristics of a microgrid is capability to supplying power to grid when there is an excess power to supply local load. This research examines the chances of saving power consumption from grid using power converters grid tie inverter (GTI) in a microgrid configuration. The test is done by …

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Surface Treatment Of Fly Ash For Improving The Tensile Strength Of Fly Ash/Unsaturated Polyester Composites, Sugiman Sugiman, Paryanto Dwi Setyawan Dec 2013

Surface Treatment Of Fly Ash For Improving The Tensile Strength Of Fly Ash/Unsaturated Polyester Composites, Sugiman Sugiman, Paryanto Dwi Setyawan

Makara Journal of Technology

The paper presents the surface treatment of fly ashes using acid and alkali solution on the tensile strength of the fly ash/unsaturated polyester (UP) composites. Sulfuric acid (H2SO4), hydrofluoric acid (HF) and sodium hydroxide (NaOH) solution with concentration of 0%, 5%, 10%, 15%, and 20% (by weight) were used for surface treatment of fly ashes. Generally, the tensile strength of the treated fly-ash/UP composites shows a significant increase compared to the untreated fly ash. Of all surface treatments studied, the optimum tensile strength was obtained at a concentration of 10%. At this concentration, at a fly ash content of 30% …

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Recycling Roof Tile Waste Material For Wall Cover Tiles, Ambar Mulyono, Silfia Mona Aryani, Joko Lulut Dec 2013

Recycling Roof Tile Waste Material For Wall Cover Tiles, Ambar Mulyono, Silfia Mona Aryani, Joko Lulut

Makara Journal of Technology

Prior research on roof tile waste treatment has attempted to find the appropriate technology to reuse old roof tile waste by create wall cladding materials from it. Through exploration and experimentation, a treatment method has been discovered to transform the tile fragments into artificial stone that resembles the shape of coral. This baked clay artificial stone material is then processed as a decorative element for vertical surfaces that are not load-bearing, such as on the interior and exterior walls of a building. Before applying the fragments as wall tiles, several steps must be taken: 1) Blunting, which changes the look …

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Semiconductor Thermal Neutron Detector, Toru Aoki, Aki Miyake, Takayuki Nakano, Akifumi Koike, Hisashi Morii, Hidenori Mimura Dec 2013

Semiconductor Thermal Neutron Detector, Toru Aoki, Aki Miyake, Takayuki Nakano, Akifumi Koike, Hisashi Morii, Hidenori Mimura

Makara Journal of Technology

The CdTe and GaN detector with a Gd converter have been developed and investigated as a neutron detector for neutron imaging. The fabricated Gd/CdTe detector with the 25 mm thick Gd was designed on the basis of simulation results of thermal neutron detection efficiency and spatial resolution. The Gd/CdTe detector shows the detection of neutron capture gamma ray emission in the 155Gd(n, g)156Gd, 157Gd(n, g)158Gd and 113Cd(n, g)114Cd reactions and characteristic X-ray emissions due to conversion-electrons generated inside the Gd film. The observed efficient thermal neutron detection with the Gd/CdTe detector shows its promise in neutron radiography application. Moreover, a …

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Small-Scale Wind Turbines: An Appraisal, Tony Kealy Sep 2013

Small-Scale Wind Turbines: An Appraisal, Tony Kealy

Conference Papers

This research seeks to evaluate the economic benefits to be gained by installing a small-scale wind turbine for a customer with a three-phase electrical supply requirement. The evidence for the claims made in this paper is obtained by using actual data obtained from the installed equipment over a three year period. The objective is to accurately appraise the financial investment using real data. There appears to be limited studies conducted into this type of research, possibly because the renewable energy sector is in the infancy stage in the host country, Ireland. There are some wind energy installations with financial appraisal …

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