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.
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. …
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 …
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–Taiwan
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 …
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–Taiwan
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 …
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–Taiwan
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 …
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–Taiwan
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 …
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–Taiwan
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 …
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–Taiwan
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–Taiwan
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 …
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 …
Biodiesel Reactor Design With Glycerol Separation To Increase Biodiesel Production Yield,
2013
Faculty of Agriculture , Universitas Siliwangi, Tasikmalaya 46115, Indonesia
Biodiesel Reactor Design With Glycerol Separation To Increase Biodiesel Production Yield, Budy Rahmat, Imas Siti Setiasih, Roni Kastaman
Makara Journal of Technology
The study consisted of reactor design used for transesterification process, effect of glycerol separation on transesterification reaction, determination of biodiesel quality, and mass balance analysis. The reactor was designed by integrating circulated pump/stirrer, static mixer, and sprayer that intensify the reaction in the outer tank reactor. The objective was to reduce the use of methanol in excess and to shorten the processing time. The results showed that the reactor that applied the glycerol separation was able to compensate for the decreased use of the reactant methanol from 6:1 to 5:1 molar ratio, and changed the mass balance in the product, …
Development Of Seebeck-Coefficient Measurement Systems Using Kelvin-Probe Force Microscopy,
2013
Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Development Of Seebeck-Coefficient Measurement Systems Using Kelvin-Probe Force Microscopy, Kazutoshi Miwa, Faiz Salleh, Hiroya Ikeda
Makara Journal of Technology
Thermoelectric device is investigated by a number of researchers in order to enhance the thermoelectric efficiency. It is known that the efficiency can be improved by quantum effect. However, it is difficult to measure the thermoelectric characteristics of nanometer-scale structures. Thus a new measurement method is expected to be developed. We propose to apply Kelvin-probe force microscopy (KFM) to characterization of thermoelectric materials. KFM can locally observe surface potential of Fermi energy of a sample without touching the sample surface. In the present paper, we estimate the Seebeck coefficient of thin Si-on-insulator layers using KFM.
Agricultural Drought Pattern In West Java Using Thermal Vegetation Index From Modis-Terra Satellite,
2013
Departement of Geography, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia
Agricultural Drought Pattern In West Java Using Thermal Vegetation Index From Modis-Terra Satellite, Dini Daruati, Rahmatulloh Rahmatulloh, Sri Hardiyanti Purwadhi
Makara Journal of Technology
This study examines agricultural drought paddy fields in West Java. The aims of this research are to know the pattern and distribution of paddy field drought in West Java and the correlation between drought and the physical characteristics. The agricultural drought is obtained from TVI (Thermal Vegetation Index) model. TVI is derived from MODIS Terra satellite image, which is the ratio between the LST (Land Surface Temperature) and EVI (Enhanced Vegetation Index). Physical factors studied are rainfall, l slope, geomorphology, soil drainage, and irrigation areas. The most severe drought occurred in September 2006 because of El Nino, covering 806,564 ha, …
Growth Of Crsi2 Nanostructures Using Crcl2 Powder On Si Substrates,
2013
Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Growth Of Crsi2 Nanostructures Using Crcl2 Powder On Si Substrates, Wen Li, Meng Erchao, Tomoji Matsushita, Shingo Oda, Daisuke Ishikawa, Kaito Nakane, Hirokazu Tatsuoka
Makara Journal of Technology
Chromium disilicide (CrSi2) nanostructures were grown by the exposure of Si (111) substrates to CrCl2 vapor in an argon gas flow at atmospheric pressure without using any metal catalyst. Dependence of the growth condition on the structural property was investigated. Hexagonal-shaped CrSi2 microrods were grown at 750 °C with 0.05 g of CrCl2. As the quantity of CrCl2 increased to 0.1 g, the bundle of CrSi2 nanowires with microrods and web-liked CrSi2 nanostructure with turning angles were grown at 750 °C and 700 °C, respectively. The preliminary discussion on the growth mechanism of CrSi2 micro- and nanostructures was carried out.
Biological Pretreatment Of Oil Palm Frond Fiber Using White-Rot Fungi For Enzymatic Saccharification,
2013
R&D Unit for Biomaterials, Indonesian Institute of Sciences, Cibinong, Bogor 16911, Indonesia
Biological Pretreatment Of Oil Palm Frond Fiber Using White-Rot Fungi For Enzymatic Saccharification, Euis Hermiati, Sita Heris Anita, Lucky Risanto, Dyah Styarini, Yanni Sudiyani, Achmad Hanafi, Haznan Abimanyu
Makara Journal of Technology
Oil palm frond is one type of lignocellulosic biomass abundantly and daily available in Indonesia. It contains cellulose which can be converted to glucose, and further processed to produce different kinds of value –added products. The aim of this research is to study the effects of biological pretreatment of oil palm frond (OPF) fiber using Phanerochaete chrysosporium and Trametes versicolor on the enzymatic saccharification of the biomass. The OPF fiber (40-60 mesh sizes) was inoculated with cultures of the two fungi and incubated at 27 °C for 4 weeks. The samples were taken after 1, 2, 3, and 4 weeks …
Electromagnetic Simulation For Thz Antenna-Coupled Microbolometers Operated At Room Temperature,
2013
Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Electromagnetic Simulation For Thz Antenna-Coupled Microbolometers Operated At Room Temperature, Makoto Aoki, Masanori Takeda, Norihisa Hiromoto
Makara Journal of Technology
Room-temperature terahertz (THz) detectors with higher performance are necessary for utilizing the THz wave in various sensing, spectroscopy and imaging, but even the best ones in the present are still insufficient for the practical applications. This issue is essential especially in the region around 1 THz at which there exists a large technology gap between microwave and middle-infrared. Therefore, we study to develop an antenna-coupled microbolometer to achieve a high-performance THz detector operated at a room-temperature for sensing at around 1 THz frequency wave. In this paper, we present several important features and results obtained from electromagnetic simulations, which help …
Analysis Of Hole Lifetime In Soi Mosfet Single-Photon Detector,
2013
Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011, Japan
Analysis Of Hole Lifetime In Soi Mosfet Single-Photon Detector, Dedy Septono Catur Putranto, Wei Du, Hiroaki Satoh, Atsushi Ono, Purnomo Sidi Priambodo, Djoko Hartanto, Hiroshi Inokawa
Makara Journal of Technology
Hole lifetime in the silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistor (MOSFET) singlephoton detector was evaluated by the analysis of drain current histograms for different light intensities and substrate voltages. It was found that the peaks in the histogram corresponding to the larger number of stored holes grew as the gate bias decreased. This was attributed not to the increased light absorption efficiency or collection efficiency of the photo-generated holes, but to the prolonged hole lifetime presumably caused by the higher transverse electric field inside the body of SOI MOSFET.
Recognition System Of Indonesia Sign Language Based On Sensor And Artificial Neural Network,
2013
Informatics Engineering Department, Muria Kudus University, Gondangmanis Kudus 59352, Indonesia
Recognition System Of Indonesia Sign Language Based On Sensor And Artificial Neural Network, Endang Supriyati, Mohammad Iqbal
Makara Journal of Technology
Sign language as a kind of gestures is one of the most natural ways of communication for most people in deaf community. The aim of the sign language recognition is to provide a translation for sign gestures into meaningful text or speech so that communication between deaf and hearing society can easily be made. In this research, the Indonesian sign language recognition system based on flex sensors and an accelerometer is developed. This recognition system uses a sensory glove to capture data. The sensor data that are processed into feature vector are the 5-fingers bending and the palm acceleration when …
Performance Optimization Of Microbial Fuel Cell (Mfc) Using Lactobacillus Bulgaricus,
2013
Chemical Engineering Department, Engineering Faculty, Universitas Indonesia, Depok 16424, Indonesia
Performance Optimization Of Microbial Fuel Cell (Mfc) Using Lactobacillus Bulgaricus, Rita Arbianti, Tania Surya Utami, Heri Hermansyah, Deni Novitasari, Ester Kristin, Ira Trisnawati
Makara Journal of Technology
Electrical energy needs in Indonesia are expected to continue to rise. The use of petroleum as a source of energy still dominates, although oil reserves in Indonesia are increasingly being depleted. Therefore, there is a need to develop alternative sources of sustainable energy, such as microbial fuel cell (MFC). In this study, Lactobacillus bulgaricus was used as an electricity producer in a dual-chamber MFC reactor. We investigated the maximum electrical energy by varying the bacterial optical density (OD), the operational time of MFC, the reactor volume, the electrolyte solution, and the configuration of MFC reactor. In this study, the maximum …
