Journal of Mathematical and Fundamental Sciences
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Estimasi Model Parametrik Komponen Feedback, Feedforward, dan Nois pada Sistem Lup Tertutup dengan Teknik Extended Least Square
Full text linkIn this paper is considered a direct estimation technique of model parameters of components (subsystems) of a feedback system using an extended least squares algorithm. There are three components of system may be estimated, feedback, feedforward, and noise. It has been assumed that the system considered was linear and time invariant. A common estimation technique for closed loop system is indirect, and under assumption that only one component will be estimated while the other components in the closed loop are known. The analysis shows that the proposed technique is unnbias. In the proposed structure, one of the components in the closed loop system maybe unstable, as long as the closed loop system is stable
Kinerja Bioreaktor Hibrid Anaerob dengan Media Batu untuk Pengolahan Air Buangan yang Mengandung Molase
Full text linkAnaerobic hybrid bioreactor is a combination of suspended and attached growth systems. Stone was used as the microorganism attachment media. The feeding solution was made from molasses diluted to COD concentration of 10,000, 20,000, 30,000 and 40,000 mg/L. The hydraulic detention time was 30 hours and the height ratio between suspended and attached growth system was 0.5. The result shows that the organic concentration seems to be on of the determining factors. Furthermore, since the methane production was still low enough, it seems that the process has not achieved its optimum condition for methanogenic stage.
Pengolahan Fasa untuk Mendapatkan Model Tinggi Permukaan Dijital (DEM) pada Radar Apertur Sintetik Interferometri (INSAR) Data Satelit
Full text linkComparing to optical sensors, radar technology has only just begun. Mapping by optical sensors, especially with Photogrammetric methode shows a very good result, but the main constraint is cloud cover conditions, and this was the weakness point of the Photogrammetric techniques. Indonesia is a tropical country which has dominant cloud coverage, and some of the area has cloud cover almost all year long. Radar imaging has some advantages e.q. sun independence, cloud penetration etc. Active systems in ERS1, ERS2, RADARSAT, JERS, and ENVISAT make possible to do interferometric processing. This paper try to explain how to process phase information from radar satellite data especially from ERS1 and ERS2. The result has been compared with the Digital Photogrammetric technigue, for Papandayan and Cikurai vulcano, West Java
Pengaruh Konsentrasi Oksidator pada Proses Hidroksilasi Minyak Jarak (Castor Oil) Dengan atau Tanpa Proteksi Gugus Hidroksi
Full text linkOil is derived from the bean of castor plant ricinus communis l., belonging to euphorbiaceae family. Oil rendement per gram of castor bean is 45 "“ 48 % with hight pure product and better than standard resulted by The Association of Official Analytical Chemistry (AOAC). The main components in castor oil are oleic, palmitic and resinoleic acid. Protection process by acetylation occurs well on hydroxyl group of castor oil, indicated by increasing of iodine number and decreasing of hydroxyl number. Oxidation process is more efective on protected oil than non protected oil. The excess of oxidator concentration changed the product to be aldehide and carboxylic acid. Optimum condition was reached when oxidator concentration was 15 %, with hydroxyl value of 1280.438 mg/g and iodine number of 33.093 mg/g
Penurunan Zat Organik dan Kekeruhan Menggunakan Teknologi Membran Ultrafiltrasi dengan Sistem Aliran Dead-End (Studi Kasus : Waduk Saguling, Padalarang)
Full text linkA laboratory scale experiment to study the aplicability of ultrafiltration membrane technology to treat the water of Saguling Reservoir has been done. The main parameters in this study are flux, organic content, and turbidity. The membranes used are cellulose accetate based membrane, composed of 11, 13, 15 percent cellulose accetate respectively. Chemical analysis of Saguling Reservoir water shows that, color, organic content, and turbidity are the parameters exceeding the standard. In this study, treated water by using Poly Alummunium Chloride (PAC) as feeding solution was also been used. The results shows that CA-15, membrane has 15 % content of cellulose accetate, performed best. The permeability of the membrane was 5-12 l/m2.hr.bar, and rejects up to 90 % of organic content, 90-100% rejection of Total Suspended Solid and 90% turbidity
Studi Pengaruh Konsentrasi Co pada Struktur Kristal dan Respon Photoluminescence Film Tipis Ti1-xCoxO2 yang Ditumbuhkan dengan Teknik MOCVD
Full text link Ti1-xCoxO2 thin films have been deposited on Si substrate by MOCVD technique. Thin films were synthesized by a single plane orientation structure of anatase-213 at various to Co concentartions up to 5,77%. Photoluminescence emission spectra of thin films showed a maximum peak at the energy of 2.8 eV. These energies did not change when increasing Co concentration in the Ti1-xCoxO2 thin films up to 5.77%. The patterns of spectrum emission only differ on the intensity and broadness of spectra. Broading occurs towards the higher energy of 2.8 eV, while the intensities were increased with increasing of Co concentration
Pengaruh Mutasi D802N pada Aktivitas Polimerase DNA Pol I ITB-1
Full text linkD802N mutant gene of DNA Pol I ITB-1 was constructed and expressed in Escherichia coli. The crude enzyme was characterized and compared to that the wild-type. The optimum pH and temperature of the mutant was slightly differences with those the wild-type. The optimum pH and temperature of the mutant were 9.0 and 50oC, while the wild-type were 7.4 and 65oC, respectively. The differences of the above properties were followed by decreasing of specific activities of the mutant (1.34 unit/mg protein) 2.7 times lower to that the wild-type (3.71 unit/mg protein). Meanwhile the catalytic efficiency (kcat/Km ) of the mutant decreased 2 times lower compared to that the wild-type. Mutation at D802N of DNA pol I ITB-1 caused decreasing on the mutant affinity to the substrate and thus loss activity and instability of the enzyme