Determining The Air Gap Length Of An Axial Flux Wound Rotor Synchronous Generator,
2013
Department of Electrical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia
Determining The Air Gap Length Of An Axial Flux Wound Rotor Synchronous Generator, Abdul Multi, Iwa Garniwa, Uno Bintang Sudibyo
Makara Journal of Technology
The air gap length of the designed axial flux wound rotor (AFWR) synchronous generator is determined properly according to the design parameters. One of the distinct advantages of an axial flux (AF) machine is its adjustable air gap. An AF generator’s performance might be controlled by adjusting its air gap. The designed generator has a smallscale capacity that has 1 kW, 380 V, and 50 Hz. The windings are laid into slots made from laminated core. The slots are carved in the face of the stator and rotors. The generator has a single-double-sided slotted wound stator sandwiched between twin rotors. …
Observation Of Photovoltaic Effect And Single-Photon Detection In Nanowire Silicon Pn-Junction,
2013
Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Observation Of Photovoltaic Effect And Single-Photon Detection In Nanowire Silicon Pn-Junction, Arief Udhiarto, Sri Purwiyanti, Daniel Moraru, Takeshi Mizuno, Michiharu Tabe
Makara Journal of Technology
We study nanowire silicon pin and pn-junctions at room and low temperature. Photovoltaic effects are observed for both devices at room temperature. At low temperature, nanowire pn-junction devices show their ability to detect single photon. This ability was not been observed for pin devices. Phosphorus-boron dopant cluster in the depletion region is considered to have the main role for single-photon detection capability. Fundamental mechanism of dopant-based single-photon detection in nanowire pn-junction is described in details.
A New Experimental Approach To Evaluate Plasma-Induced Damage In Microcantilever,
2013
Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
A New Experimental Approach To Evaluate Plasma-Induced Damage In Microcantilever, Yuki Nishimori, Shinji Ueki, Masakazu Sugiyama, Seiji Samukawa, Gen Hashiguchi
Makara Journal of Technology
Plasma etching, during micro-fabrication processing is indispensable for fabricating MEMS structures. During the plasma processes, two major matters, charged ions and vacuum–ultraviolet (VUV) irradiation damage, take charge of reliability degradation. The charged ions induce unwanted sidewall etching, generally called as “notching”, which causes degradation in brittle strength. Furthermore, the VUV irradiation gives rise to crystal defects on the etching surface. To overcome the problem, neutral beam etching (NBE), which use neutral particles without the VUV irradiation, has been developed. In order to evaluate the effect of the NBE quantitatively, we measured the resonance property of a micro-cantilever before and after …
Influences Of Surface Morphology Of Nanostructured Rutile Tio2 Nanorods/Nanoflowers As Photoelectrode On The Performance Of Dye-Sensitized Solar Cell,
2013
Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Influences Of Surface Morphology Of Nanostructured Rutile Tio2 Nanorods/Nanoflowers As Photoelectrode On The Performance Of Dye-Sensitized Solar Cell, Mohd Khairul Bin Ahmad, Kenji Murakami
Makara Journal of Technology
Aligned Rutile TiO2 nanorods (r-TNRs) and TiO2 nanoflowers (r-TNFs) were successfully prepared by hydrothermal method. Using hydrochloric acid (HCl) as chelating agent and titanium butoxide (TBOT) as precursor, aligned r-TNRs with r-TNFs were successfully growth onto fluorine-doped tin oxide (FTO) with different morphologies. The influences of surface morphologies to the rutile based Dye-sensitized solar cell (DSC) efficiency are discussed. The highest lightto- electric energy conversion efficiency, 1.80% is achieved using different concentration under simulated solar light illumination of 100 mWcm-2 (1.5 AM).
Improvement In Performance Of Zno Based Dsc Prepared By Spraying Method,
2013
Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Improvement In Performance Of Zno Based Dsc Prepared By Spraying Method, Rangga Winantyo, Devinda Liyanage, Kenji Murakami
Makara Journal of Technology
This paper reports the effect of TiCl4 on the performance of ZnO based DSC. ZnO was used due to its stability against photo-corrosion and photochemical properties similar to TiO2. Thin films of nanocrystalline ZnO were deposited on transparent conducting oxide glass using spray method. The ZnO films were treated using TiCl4. The cell’s efficiency was found to be 2.5% with TiCl4 post-treatment and 1.9% without TiCl4 post-treatment.
Characteristics Of Vacuum Freeze Drying With Utilization Of Internal Cooling And Condenser Waste Heat For Sublimation,
2013
Department of Mechanical Engineering, Universitas Indonesia, Depok 16424, Indonesia
Characteristics Of Vacuum Freeze Drying With Utilization Of Internal Cooling And Condenser Waste Heat For Sublimation, Muhammad Idrus Alhamid, Nasruddin Yusuf, Indra Teuku Meurah Mahlia, Engkos Ahmad Kosasih, Muhamad Yulianto, Rio Ricardi
Makara Journal of Technology
Vacuum freeze drying is an excellent drying method, but it is very energy-intensive because a relatively long drying time is required. This research investigates the utilization of condenser waste heat for sublimation as a way of accelerating the drying rate. In addition, it also investigates the effect of internal cooling combined with vacuum cooling in the pressure reduction process. Jelly fish tentacles were used as the specimen, with different configurations for condenser heat waste and internal cooling valve opening. The results show that heating with condenser heat waste can accelerate the drying rate up to 0.0035 kg/m2.s. In addition, pre-freezing …
The Plasma Electrolysis Phenomenon In A Two-Compartment Reactor For Chlor-Alkali Production,
2013
Department of Chemical Engineering, Universitas Indonesia, Depok 16424, Indonesia
The Plasma Electrolysis Phenomenon In A Two-Compartment Reactor For Chlor-Alkali Production, Nelson Saksono, Fakhrian Abqari, Setijo Bismo
Makara Journal of Technology
Chlor-alkali is one of the most important processes in the chemical industry. It produces chlorine and caustic soda, which become the main feedstock of daily products. The aim of this study is to report the phenomenon of plasma electrolysis and how it can be used in chlor-alkali production for more efficient energy consumption. When the plasma is formed, the current fluctuates and gradually declines. Plasma electrolysis begins with the process of electrolysis itself. Due to Joule heating, gas bubbles are formed and a sheath is made on both electrodes, resulting in the plasma field. Plasma electrolysis can be identified by …
Fatigue Life Prediction Of The Keel Structure Of A Tsunami Buoy Using Spectral Fatigue Analysis Method,
2013
Department of Naval Architecture and Shipbuilding Engineering, Faculty of Marine Technology, Institut Teknologi Sepuluh Nopember (ITS), Surabaya 60111, Indonesia
Fatigue Life Prediction Of The Keel Structure Of A Tsunami Buoy Using Spectral Fatigue Analysis Method, Angga Yustiawan, Ketut Suastika, Wibowo Harso Nugroho
Makara Journal of Technology
One of the components of the Indonesia Tsunami Early Warning System (InaTEWS) is a surface buoy. The surface buoy is exposed to dynamic and random loadings while operating at sea, particularly due to waves. Because of the cyclic nature of the wave load, this may result in a fatigue damage of the keel structure, which connects the mooring line with the buoy hull. The operating location of the buoy is off the Java South Coast at the coordinate (10.3998 S, 108.3417 E). To determine the stress transfer function, model tests were performed, measuring the buoy motions and the stress at …
Production Optimization For Plan Of Gas Field Development Using Marginal Cost Analysis,
2013
Chemical Engineering Department, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia
Production Optimization For Plan Of Gas Field Development Using Marginal Cost Analysis, Suprapto Soemardan, Widodo Wahyu Purwanto, Arsegianto Arsegianto
Makara Journal of Technology
Gas production rate is one of the most important variables affecting the feasibility plan of gas field development. It take into account reservoir characteristics, gas reserves, number of wells, production facilities, government take and market conditions. In this research, a mathematical model of gas production optimization has been developed using marginal cost analysis in determining the optimum gas production rate for economic profit, by employing the case study of Matindok Field. The results show that the optimum gas production rate is mainly affected by gas price duration and time of gas delivery. When the price of gas increases, the optimum …
Design, Optimization, And Testing Of A Cross-Flow Tidal Turbine,
2013
The University of Maine
Design, Optimization, And Testing Of A Cross-Flow Tidal Turbine, Megan Colleen Swanger
Electronic Theses and Dissertations
This thesis is a summary of testing conducted with a Darrieus style cross-flow tidal turbine. Many locations around the world have locations suitable for tidal turbine energy, including the Cobscook Bay in Eastport, Maine. Cross-flow turbines are likely to have a smaller impact on the environment compared to axial flow turbines due to their operation at lower tip speed ratios. Since very little experimental data is available presently for cross-flow turbines, this study provides an expansive set of performance data for two NACA series blade profiles of the same chord length. One blade profile was used in two different orientations …
Aqueous Turbulence Structure Immediately Adjacent To The Air - Water Interface And Interfacial Gas Exchange,
2013
University of Wisconsin-Milwaukee
Aqueous Turbulence Structure Immediately Adjacent To The Air - Water Interface And Interfacial Gas Exchange, Binbin Wang
Theses and Dissertations
Air-sea interaction and the interfacial exchange of gas across the air-water interface are of great importance in coupled atmospheric-oceanic environmental systems. Aqueous turbulence structure immediately adjacent to the air-water interface is the combined result of wind, surface waves, currents and other environmental forces and plays a key role in energy budgets, gas fluxes and hence the global climate system. However, the quantification of turbulence structure sufficiently close to the air-water interface is extremely difficult. The physical relationship between interfacial gas exchange and near surface turbulence remains insufficiently investigated. This dissertation aims to measure turbulence in situ in a complex environmental …
Pfi: Commercialization Of Advanced Composites In Offshore Wind Energy,
2013
Principal Investigator; University of Maine, Orono
Pfi: Commercialization Of Advanced Composites In Offshore Wind Energy, James Ward, Habib J. Dagher, Robert Lindyberg
University of Maine Office of Research Administration: Grant Reports
This Partnerships for Innovation (PFI) project--a Type III (A:C) partnership between the University of Maine (UMaine), an NSF PFI graduated grantee (0125343), and Maine Maritime Academy, an institution new to the PFI Program (defined as one that has never been a PFI grantee) and, in this case, new to NSF as well seeks to enable the acceleration of the development of Maine's deepwater offshore wind energy resource by employing an innovation model that will draw upon knowledge and technology from diverse sources. The proposed research addresses the development of key knowledge, experimentally-validated numerical models for combined aerolastic/hydrodynamic loadings; and an …
The Experimental Study On Local Scour Around A Circular Pipe Undergoing Vortex-Induced Vibration In Steady Flow,
2013
School of Civil Engineering, Southwest Jiaotong University, Chengdu, China.
The Experimental Study On Local Scour Around A Circular Pipe Undergoing Vortex-Induced Vibration In Steady Flow, Bing Yang, Tao Yang, Jian-Lin Ma, Jin-Sheng Cui
Journal of Marine Science and Technology
The local scour around a circular pipe undergoing vortexinduced vibration is investigated experimentally in a water flume. The typical characteristic of local scour is analyzed in detail. The influences of initial gap-to-diameter ratio (e0/D), the mode of pipe vibration and the sand type on the local scour are discussed. Experimental results indicate that there exists strong intensity of scour when the pipe moves close to the surface of the sandy bed. The vibration of the pipe results in the rapid development of sandy bed’s scouring. With the increase of gap-to-diameter ratio the distance between the center of the pipe and …
Application Of A Support Vector Machine For Liquefaction Assessment,
2013
Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
Application Of A Support Vector Machine For Liquefaction Assessment, Ching-Yinn Lee, Shuh-Gi Chern
Journal of Marine Science and Technology
This study presents a support vector machine (SVM)-based approach for predicting earthquake liquefaction. The SVM model database includes five indexes: earthquake magnitude, total overburden pressure, effective overburden pressure, qc values from cone penetration tests (CPT), and peak ground acceleration. The proposed model was trained and tested on a dataset comprising 466 field liquefaction performance records and CPT measurements. A grid search method with k-fold cross-validation was also used to verify the feasibility. Compared with an artificial neural network (ANN)–based method, the SVM-based method has the advantage of increased accuracy and simpler operation. Experimental results show that the proposed SVM approach …
A Piston-Type Porous Wave Energy Converter Theory,
2013
Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
A Piston-Type Porous Wave Energy Converter Theory, Ching-Yun Yueh, Shih-Hsuan Chuang
Journal of Marine Science and Technology
This study investigates the performance of a piston-type porous wave energy converter (PTPWEC), which consists of a solid wall, a vertical porous plate, a transmission bar, a rigid block constrained by rollers, a spring, and a damper. The PTPWEC is subjected to dynamic external loading by wave actions. To simulate this dynamic system, a mathematical model is used with a single-degree-of-freedom (SDOF) system. Linear wave theory governs the entire fluid domain, which is divided into two regions by the vertical porous plate. Darcy's law is applied to flow through the porous plate. Finally, this investigation employs an eigenfunction expansion to …
Numerical Simulations And Wind Tunnel Studies Of Pollutant Dispersion In The Urban Street Canyons With Different Height Arrangements,
2013
Department of Civil Engineering, Tamkang University, Tamsui, Taipei County, Taiwan, R.O.C
Numerical Simulations And Wind Tunnel Studies Of Pollutant Dispersion In The Urban Street Canyons With Different Height Arrangements, Cheng-Hsin Chang, Jin-Shian Lin, Chii-Ming Cheng, Yung-Shan Hong
Journal of Marine Science and Technology
Air pollution in big city areas resulting from exhaust emissions is a major urban problem. Often traffic pollution excess controls air pollution management decisions. There are a number of elaborate predictive models of pollutant dispersion and diffusion that address the effects of variable shapes of city buildings on pollutant concentrations, but few are fully validated. This study presents ventilation behavior in different street canyon configurations. To evaluate dispersion in a model urban street canyon, a series of tests with various street canyons with different height in upwind and downwind of street canyon are presented. These buildings were arranged in 2-D …
An Improvement Of Wave Refraction-Diffraction Effect In Swan,
2013
Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
An Improvement Of Wave Refraction-Diffraction Effect In Swan, Aw-Guei Lin
Journal of Marine Science and Technology
SWAN, a wind wave model, has been modified to take into account wave refraction-diffraction effects from the extended mild-slope equation when wind waves pass through a extremely uneven sea bottom in the presence of current. In our modified model, the diffraction correction parameter introduced by Holthuijsen et al. [10] has been adjusted to better predict the combined effect of the higher-order bottom effect, wave-bottom interaction and wave-current interaction. After a preliminary analysis, the influence of the correction parameter is discussed, and a comparison is made between the original and the new phase-decoupled versions of SWAN through some typical examples of …
An Experimental Study Of Regular Long Crested Waves Over A Crescent Type Shoal,
2013
Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
An Experimental Study Of Regular Long Crested Waves Over A Crescent Type Shoal, Wen-Kai Weng, Jaw-Guei Lin, Chun-Sien Hsiao
Journal of Marine Science and Technology
Converting the ocean wave energy into electric power is one possibility of the development of alternative and nonpolluting sources of energy. Many researches concerning converters and their converting efficiency of wave power were developed and discussed in the last years. However, converting wave energy into electric power does not only depend upon converting system but condition of sea state essentially. A calm sea state with lower wave energy is difficult to drive converting device working and is unable to satisfy the minimum economical requirement. Unfortunately, wave heights in the sea state around Taiwan are mostly too smaller to extract the …
Vibration Suppression Of Train-Induced Multiple Resonant Responses Of Two-Span Continuous Bridges Using Ve Dampers,
2013
School of Civil Engineering, Beijing Jiaotong University,Beijing, China.Department of Civil and Environmental Engineering, Rutgers, The State University of New Jersey, New Jersey, USA
Vibration Suppression Of Train-Induced Multiple Resonant Responses Of Two-Span Continuous Bridges Using Ve Dampers, Ying-Jie Wang, Jong-Dar Yau, Qing-Chao Wei
Journal of Marine Science and Technology
This paper presents a study of reducing multiple resonant peaks of high-speed trains traveling over a two-span continuous railway bridge using visco-elastic (VE) dampers. The moving train is modeled as a series of two-degree-of-freedom (2 DOF) moving oscillators with identical intervals and the two-span continuous bridge as a Bernoulli-Euler beam with uniform span. Because of closely spaced frequencies of a continuous beam, the first several frequencies of the bridge would be excited to resonance during the passage of moving trains, which may result in multiple resonant peaks appearing on the response of train-bridge system. In order to reduce the multiple …
Development Of Cfd Models For The Purposes Of Exploring Free Surface Wave Phenomena,
2013
Western Michigan University
Development Of Cfd Models For The Purposes Of Exploring Free Surface Wave Phenomena, Leonard P. Stoehr
Masters Theses
With the push for finding alternative, green energy sources, the harnessing of energy from ocean and lake waves is becoming a more researched field. To fully understand the behavior of wave interactions and optimize designs to extract this energy, it is necessary to develop computer models that can accurately replicate this behavior. A case is presented in which previous work done using the wave tank found in the Western Michigan University fluids lab is examined. The case involves harnessing the energy generated by ocean waves through the usage of plates of different shapes resting horizontally on the water’s surface. The …
