Makara Journal of Science
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POLA PERSEBARAN INDUSTRI DI KORIDOR JALAN RAYA BOGOR
No full textSpatial dispersed pattern of Industry at Jalan Raya Bogor Corridor. The corridor Jalan Raya Bogor, includes DKI Jakarta and West Java provinces have 186 industry, which different spatial dispersed pattern. The Industry has an impact to local community for worker industry. The analysis with nearness neighborhood and overlay map are conclusion as industry has cluster pattern at Cisalak Pasar, Cilangkap, and Cisalak district. And the industry patterns have random spatial at Tugu, Mekarsari, Sukamaju Baru, and Jatijajar district. The industry spatial has a dispersed pattern/uniform at Susukan, Ciracas, Pekayon, Curug, and Sukamaju district. The local community for worker industry has 62.04% senior high school and 2.81% elementary school or not education.Keywords: middle industry region, local community in worker industry
REFLECTION INFLUENCE ON OUTPUT FREQUENCY SPECTRUM AT SUBMILLIMETER FREQUENCY TUNABLE GYROTRONS
No full textInfluence of output window reflections on oscillatory processes in gyrotrons has been studied. The processes in a gyrotron have been modeled numerically, and enhancement of the spectrum signal in the presence of reflections has been studied. Dependencies of output power versus time and frequency spectrum for different value of reflection coefficient are given. Possibilities of significant increasing of output spectrum are demonstrated experimentally. The results demonstrate significant influence of reflections on operation stability and composition of the output radiation of the gyrotron.Keywords: gyrotron, tunability, reflections, oscillation regime, radiation spectru
SUSCEPTIBILITY MAGNETIC AND HIGH MAGNETIC FIELD ESR MEASUREMENT OF SrCu2(PO4)2
No full textThe magnetic susceptibility and high magnetic ESR measurement of SrCu2(PO4)2 has been performed at temperatures ranging from 4.2 K to 300 K and 4.2 K to 77 K, respectively. The magnetic susceptibility shows a broad maximum around T = 40 K. The magnetic susceptibility has been interpreted in terms of one-dimensional magnetic systems. The temperature dependence of the magnetic susceptibility indicated a good agreement with 4-spin alternating configuration model. In the ESR measurement, clear electron spin resonance (ESR) was observed. The integrated intensity for 120 and 301 GHz has a broad maximum at around 40 K, which is consistent with the susceptibility result. A quantitative description gives resonance is the first and second triplet excited states of the excitation spectrum of 4-spin alternating chain configuration. The g1, g2 and g3 values are approximately 2.21 at temperature above 40 K. The g2 dan g3 values have the dependence of temperature under 40 K. Keywords: magnetic susceptibility, electron spin resonance, singlet ground state, triplet excited states, 4-spin alternating chai
A NUMERICAL EXPERIMENT OF 50-DAY RESONANCE INDUCED BY INDIAN OCEAN KELVIN WAVE IN THE SULAWESI SEA
No full textA numerical ocean modeling study using spectral element method is used to simulate the Indian Ocean Kelvin wavepropagation along the Makassar Strait and the Sulawesi Sea by giving a-prescribed-50-day Kelvin wave forcing in the northern mouth of the Lombok Strait. The least square fit analysis is employed to extract a-50-day-resonant signal from the interface height data simulation. The results indicate that the 50-day Kelvin wave propagates northward along the Makassar Strait. One part of this wave turns back at the Labani channel and makes southward propagation along the eastern coast of the Makassar Strait. The rest part is going further to enter the Sulawesi Sea and makes 50-day resonance within the basin. This finding will have important implication on the intra-seasonal time scale variability of the Indonesian throughflow transport entering the Indonesian Seas and needs further investigation as well as comparison with observational data.Keywords: A-50-day resonance of Indian Ocean Kelvin wave, Spectral Element Ocean Model (SEOM), the Least-square fit extraction, Indonesian throughflow
PENGEMBANGAN DATABASE MIKROORGANISME INDIGENOS INDONESIA
No full textDevelopment of Database for Indigenous Indonesian Microorganisms. The objective of the research is to create and develop a database of indigenous Indonesian microorganisms based at the University of Indonesia. Development of the database of indigenous Indonesian microorganisms was carried out in several stages, i.e. data identification, database design, programming, data entry, testing and debugging, and repairing and maintenance. Development of the database utilized the licensed software of General Public License (GPL), which include Linux RedHat 9.0 (operating system), Apache ver. 2.20 (web server), MySQL ver. 4.2 (database server), and PHP ver. 4.3 (web interface programming language). The result of this research is a database named UI Bioinfo which has the following facilities: online catalog search for UICC (University of Indonesia Culture Collection) strains collection and sequence homology search utility through BLAST (Basic Local Alignment Search Tool). Integrated information on strains collection was first carried out on the yeast collection. At present, UI Bioinfo contains information for 297 strains that includes isolation data, morphological descriptions, physiology-biochemical characteristics, and images. Moreover it also contains sequence data from the large subunit (LSU) ribosomal RNA gene and the internal transcribed spacer (ITS) regions. UI Bioinfo can be accessed from the following site: http://152.118.162.250/bio/. Future development will be addition of data from the other collections in UICC. Keywords:Bioinformatics, database, Indonesia, microorganism
A STUDY OF CLAY-EPOXY NANOCOMPOSITES CONSISTING OF UNMODIFIED CLAY AND ORGANO CLAY
No full textClay-epoxy nanocomposites were synthesized from DGEBA resin and montmorillonite clay with an in-situ polymerization. One type of untreated clay and two types of organo clay were used to produce the nanocompsoites. The aims of this study were to examine the nanocomposite structure using different tools and to compare the results between the unmodified clay and modified clays as nanofillers. Although diffractogram in reflection mode did not show any apparent peak of both types of materials, the transmitted XRD (X-Ray Difraction) graphs, DSC (Differential Scanning Calorimeter) analysis and TEM (Transmission Electron Microscope) images revealed that the modified clay-epoxy and unmodified clay-epoxy provides different results. Interestingly, the micrographs showed that some of the modified clay layers possessed non-exfoliated layers in the modified clay-epoxy nanocomposites. Clay aggregates and a hackle pattern were found from E-SEM images for both types of nanocomposite materials. It is shown that different tools should be used to determine the nanocomposite structure. Keywords: epoxy resin, montmorillonite, XRD, DS
Penggunaan Algoritma Genetika Untuk Optimasi Jaringan Neural Buatan-Fuzzy Dan Aplikasinya Pada Sistem Penciuman Elektronik
No full text<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-1610611985 1107304683 0 0 159 0;} @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-1610611985 1073750139 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin-top:0in; margin-right:0in; margin-bottom:10.0pt; margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} .MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} .MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> In this article we proposed a method for optimizing the structure of a fuzzy artifi cial neural networks (FANN) through genetic algorithms. This genetic algorithm (GA) is used to optimize the number of weight connections in a neural network structure, by evolutionary calculating the fi tness function of those structures as individuals in a population. This fuzzy neural is then applied as the pattern recognition in our developed odor recognition system. Experimental results show that the optimized neural system provides higher recognition capability compare with that of unoptimized neural system. Recognition rate of the unoptimized neural structure is 70.4% and could be increased up to 85.2% in the optimized neural system. It is also shown that the computational cost of the optimized structure of neural system is also lower than the unoptimized structure. Keywords: Optimizing, artifi cial neural network, fuzzy logical, genetic algorithm, electric sensing syste
Perbedaan Perluasan Daerah Tutupan Pada Wilayah Permukimandi Kotamadya Depok
No full textThe Depok Land Use Planning predicts that in 2010, urban land use will be 73 percent, while 63 percent is for settlement. Depok is allocated for catchment area, so the expansion of paving area should be monitor. In this study, there were four typesof settlement lower and middle type in perumnas and in middle type (perumnas kecil dan besar serta perumahan sederhana kecil dan besar). Average of paved area in the perumnas kecil was 66 m², in perumnas besar was 89.5 m². In perumahan sederhana kecil was 54.4 m² and in perumahan sederhana besar was 121.3 m². Land square meter and length of stay were the variables that infl uence the expansion of paved area. They did that because they have more space to expand their house, and now, there was no open space left.Keywords: Paved area, type of settlemen
Studi Hidrologi Hutan Kota Kampus Universitas Indonesia Depok
No full textHydrological Study on the urban forest in Campus Area of the Indonesia University, Depok during September 2000– February 2001 hydrological measurement of urban forest in Campus Area of the Indonesia University, Depok werecarried out to identify the effect of land cover on the runoff generation processes. Seven observation station which arecharacteristised by differenced land cover were build to measure overland and sub surface fl ow. The result of data analysisshowed that the grass and litter cover in urban forest fl oor played an important role as a control factor of overland fl ow and throughfl ow production, especially signifi cant during the convective rains. During this events the proportion of throughfall on this area which produced overland fl ow, varied between 5,3-7,2%, while on the area without the grass and litter cover, its about 12,5-18,9%. During December–February the overland fl ow was very high. This is probably closely related to the existence of the widespread saturation overland fl ow. Generally it was shown a very close relationship between throughfall and overlandfl ow on the area without the grass and litter cover. The effect of antecedent precipitation index on the overland and throughfl ow production was identifi ed on the location with grass cover and cultivated area and particularly signifi cant on the events with throughfall >40 mm.Keywords: Overland flow, saturation overland fl ow, subsurface fl ow, through fall, antecedent precipitation inde
BIODIVERSITAS EKHINODERMATA DI PERAIRAN PANTAI TAKOFI, PULAU MOTI – MALUKU UTARA
No full textEchinoderm Biodiversity in the Takofi Coastal Waters, Moti Island, North Maluku. A total of 22 echinoderm species were found in Takofi waters, North Maluku. They were represented by 6 species of holothuroidea, 4 species of asteroidea, 5 species of echinoidea and 7 species of ophiuroidea. The Ophiuroidea were relatively common in seagrass area. The quantitative analysis on the abundance data revealed the highest diversity index of faunal assemblage at station II (H’=1.19). The highest evenness index was exhibited by the echinoderms from station III (J = 0.99), while the highest species richness was represented by them from station I (D = 1.22). Keywords: Echinoderm, Takofi, Maluku Utar