MAKARA Journal of Technology
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BENCHMARK FOR COUNTRY-LEVEL EARTHQUAKE STRONG-MOTION INSTRUMENTATION PROGRAM
An empirical study to develop benchmark models at country-level to assess the suggested number of earthquake strong-motion stations based on a framework encompassing geographic, demographic, and socio-economic parameters is reported. The models are to provide a working estimate of the required number of stations for improving the strong-motion instrumentation program of Indonesia. National earthquake strong-motion networks of New Zealand, Japan, Taiwan, Iran, Turkey, and Italy were used as the references. The parameter proposed is the number of stations in land area of 1,000 km2, and three models based on the exponential regression analysis are presented as functions of population density, Gross Domestic Product (GDP) per capita, and the Global Competitiveness Index (GCI) Basic Requirements Index. Using the models, it is suggested that Indonesia would require at least 750 stations. Keywords: benchmark, earthquake, strong-motion network, strong-motion instrument
PENERAPAN METODE PRINCIPAL COMPONENT PROXIMITY TRANSFORM DAN GEOSTATISTIK UNTUK PEMODELAN PENYEBARAN VOLUME SHALE SEBAGAI PENCITRAAN KARAKTERISTIK RESERVOIR PADA SEISMIC 3D
Application of Principal Component Proximity Transform and Geostatistics Methods for Volume Shale Distribution as Reservoir Characreristic Imaging in Seismic 3D. Principal component proximity transform (PCPT) technique was used to predict the content of volume shale into seismic data in reservoir modeling framework. The goal in this research is to get the volume shale imaging in three dimensions and allow for reservoir modelling. The reservoirmodelling requires an integrated quantitative and qualitative data sources collected separately, such as well and seismic data. Integrating PCPT and Geostatistic methods can generate the detail information for characterization of reservoir’s properties. Finally, it shows that the model was valid with correlation coefficient of 0.986 between volume shale in the well and predicted volume shale in the seismic. Reservoir zone can be found with low level of volume shale (<0.5) that it was visualized by colour dark-grey.Keywords: geostatistic, PCPT, reservoir, seismic, volume shal
SMALL SCALE EXPERIMENT: THERMAL PERFORMANCE COMPARISON BETWEEN FIBER-CEMENT ROOF AND PHOTOVOLTAIC ROOF IN MALANG, INDONESIA
Irradiation on the surface of photovoltaic module heats up the photovoltaic module itself and the room underneath the roof of integrated photovoltaic building in the tropics area. Room heating reduces thermal condition and photovoltaic module surface heating reduces its performance in generating electricity. This paper discusses an experiment of measuring the surface temperature of photovoltaic modules and fiber-cement roof surface as a comparison. This experiment also measures the impact of rising temperatures in each space underneath. It used small-scale mock-ups exposed to direct sunlight. The result of the experiment shows that photovoltaic roof surface temperature is lower than fiber-cement roof temperature. The temperature of room under photovoltaic roof is also lower than the one under fiber-cement roof. Empirical calculation shows that loss of electrical power found is only up to 1.7%. Keywords: electrical power loss, fiber-semen roof, roof integrated photovoltaic, small scale experiment, thermal performanc
PEMBENTUKAN KODE TELAPAK TANGAN (PALM CODE) BERBASIS METODE GABOR 2D
Establishment Code Hand Palm (Palm Code) 2D Gabor-Based Method. Palmprint is relatively new in physiological biometrics. Palmprint ROI segmentation and feature extraction are two important issues in palm print recognition. This paper introduces two steps in the center of mass moment method for ROI segmentation that will be applied in the Gabor 2D filter to obtain palm code as palmprint feature vector. Normalized Hamming distance was used to measure the similarity degrees of two feature vectors of palmprint. The system was tested using database 1000 palmprint images generated from 5 samples from each of the 200 persons randomly selected with ROI 64 x 64 and 128 x 128 pixel. Experiment results show that this system can achieve high performance with a success rate about 98.7% (FRR = 1.17%, FAR = 0.11%, T = 0.376) with ROI 64 x 64 pixel.Keywords: biometrics, Gabor filter, Hamming distance, identification, palmprin
PHYSICO-CHEMICAL, AND SENSORY PROPERTIES OF SOY BASED GOUDA CHEESE ANALOG MADE FROM DIFFERENT CONCENTRATION OF FAT, SODIUM CITRATE AND VARIOUS CHEESE STARTER CULTURES
Gouda cheese analog (GCA) was made using soy protein isolate (SPI), skim milk powder (SMP), fat (palm fat and butter fat), and water (W) at optimal ratio of SPI : SMP : F : W = 14 : 6 : 20 : 60. The effects of butter fat, sodium citrate, and cheese starter culture on the sensory properties of ripened product were assessed by preference test, hedonic test, and the texture profile analysis (TPA) of GCA. The free fatty acids, water-soluble nitrogen, and reduction in pH value of progel were also measured. The use of 100% butter fat (BF) produced strong Gouda flavor. It could be due to the fatty acids content in BF; in contrast, product with 100% palm fat (PF) produced tasteless GCA. It might be due to fatty acids content in PF, middle, and long chain fatty acids. Single cheese starter culture could not develop Gouda flavor during ripening. The use of mixed fat (50% BF and 50% PF) and mixed cheese starter culture together with Brevibacterium linens developed a suitable characteristic flavor of Gouda product during ripening. The addition of 0.5% sodium citrate could improve the flavor; nevertheless, it reduced the stability of texture.Keywords: butter fat, citrate, flavor, GCA, soy protein isolat
CDM POTENTIAL IN PALM SOLID WASTE COGENERATION AS AN ALTERNATIVE ENERGY IN ACEH PROVINCE
Empty Fruit Bunch (EFB) as a solid waste in Crude Palm Oil (CPO) industry does not utilized yet as an alternative energy source to generate electricity. It is well known that use of solid wate (biomass) as an energy source is part of the Clean Development Mechanism (CDM) scheme due to direct reduction of Green House Gases (GHGs) emission and provide a direct contribution to sustainable development. Utilization of EFB as a source of energy is very potential to be implemented in Aceh since this province has 25 CPO Mills at the moment which actively produce about 870,000 ton EFB per year. This study is subjected to evaluate the potency of electricity from EFB theoretically by using primary data (survey data) and secondary data. Potency of EFB and number of electricity produced from that EFB are estimated using primary data and direct combustion scenario, respectively. Calculation methods for emission reduction acieved are done by AMS-I.D: Renewable electricity generation to the grid and AMS-III.E: Methane emissions avoided from dumping at a solid waste disposal site. The result of this investigation shows that energy consumption in 25 CPO Mills is 45 GW(e)h per year. Evidently, the number of energy/electricity which is potential to be produced by using 75% EFB is 1,047 GWh per year; so that the GHGs emission reduction up to 171,232.21 tCO2e per year.Keywords: empty fruit bunch, clean development mechanism, GHGs emission, renewable energ
Growth of CrSi2 Nanostructures Using CrCl2 Powder on Si Substrates
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.Keywords: CrSi2, microrods, nanostructures, thermoelectric materia
OPTIMATION OF NITROGEN AND PHOSPHORUS IN AZOLLA GROWTH AS BIOFERTILIZER
Nitrogen is one of the most important minerals for living organisms. Azolla is known as a small water fern which can fix nitrogen through the symbiotic association with the blue green algae Anabaena. Experimental studies were carried out in the glass house, investigating the growth of Azolla using different levels of nitrogen and phosphorus in the media. The experiment used 12 treatments with 3 levels of nitrogen (0, 5, and 10 mg atom/L) and 4 levels of phosphorus (0, 10, 20, and 30 mg atom/l) in a factorial design with 3 replicates. The results show that the highest biomass for fresh weight(13.28 g), dry weight (1,126 g), and the fastest doubling time (7.71 days) were found in combination of 10 mg atom/L N and 30 mg atom/L P. Meanwhile, the highest protein content was found in combination of 5 mg atom/L N and 20 mg atom/L P. After the third day heterocyst cells in Anabaena could only be found in those two combinations, but the highest heterocyst cells was found in the lower N and P combination similar to the highest protein content. Further experiment is suggested to introduce Azolla as bio-fertilizer for acid water system, such as peat land water.Keywords: Azolla microphylla, Anabaena azolae, bio-fertilizer, protein conten
DEVELOPMENT OF LOCAL-ECONOMIC-DEVELOPMENT SMALL AND MEDIUM INDUSTRIES (LED-SME) IN EAST JAVA
This paper presents the effects of Indonesian government’s developmental efforts of assistance and training performed on the growth of LED-SME business units and business performance. Both parameters of the government’s assistance and training were used to analyze the impact to the growth and performance of business unit. To achieve a comprehensive result, samples acquired in this research were about 190 entrepreneurs and managers of LED-SME from East Java. Based on the parameters above, there are five hypotheses made to prove the relationship of the assistance and training to the growth and performance of business units. The structural equation modeling (SEM) was carried out to test the hypotheses. The results have shown that the government’s developmental efforts through both assistance and training for the LED-SME were capable on increasing growth and performance of business units. On the other hand, government’s developmental efforts through only trainings were incapable of directly affecting growth of LED-SME business units and performance. To improve the business unit and performance, the government needs to implement developmental principles of LED-SME with the basis of utilizing local natural resources and also the communities of LED-SME as main suppliers for their local markets. In addition, preservation and development of local cultural and traditional arts also need to be the government’s main concern. Keywords: government’s assistance and training, growth and performance of business uni
Analysis of Hole Lifetime in SOI MOSFET Single-Photon Detector
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.Keywords: hole lifetime SOI MOSFET, light absorption efficiency, single-photon detecto