MAKARA Journal of Technology
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TWO-CLASS CLASSIFICATION WITH VARIOUS CHARACTERISTICS BASED ON KERNEL PRINCIPAL COMPONENT ANALYSIS AND SUPPORT VECTOR MACHINES
Two class pattern classification problems appeared in many applications. In some applications, the characteristic of the members in a class is dissimilar. This paper proposed a classification system for this problem. The proposed system was developed based on the combination of kernel principal component analysis (KPCA) and support vector machines (SVMs). This system has been implemented in a two class face recognition problem. The average of the classification rate in this face image classification is 82.5%. Keywords: characteristic, classification, face recognition, kernel principal component analysis, support vector machine
EFFECT OF DIAFILTRATION ON PREPARATION OF FERMENTED MUNG BEANS CONCENTRATE AS PROBIOTIC SAVORY FLAVOR THROUGH ULTRAFILTRATION MEMBRANE
Diafiltration by means of the ultrafiltration system of probiotic fermented Mung beans (Phaseolus radiatus L.) concentrate has been performed to reduce or eliminate salts and smaller impurities than the nominal cut-off of the membrane of 20,000 nominal weight cut-off (NWCO). These processes have been conducted as an attempt in order to get a probiotic product with organoleptic acceptability, composition, and the optimal total lactic acid bacteria (LAB) counts because the presence of salts will affect on the viability of LAB and the cell lysis of LAB and limit its utility in food products. Concentrate of probiotic mung beans was prepared through fermentation of LAB using inoculum of LAB consisting of Lactobacillus bulgaricus and Streptococcus thermophylus (1 : 1) on fermented mung beans extractinoculated by inoculum of Rhizopus–C1 in rice substrates at salt condition. Ultrafiltration and diafiltration modes have been carried out at flow rate of 8.77 Liter/minute, room temperature and the pressure of 5 bar (0 to 79.7 minutes) and 7 bar (0-154.5 minutes) with the ratio of the volume of pure water to the volume of initial feed (number of diavolume, Nd) of 0, 0.25, 0.5, 0.75, 1.0 and 1.25, respectively. The experiment results based on total LAB counts as a probiotic product show that a high Nd can reduce the salt content but increase the total LAB counts. Nd of 1.0 results reduce the salt content which is equal to retentate, permeate, and the optimal total LAB counts. Ultrafiltration and diafiltration modes at the pressure of 7 bar and Nd of 1.0 give a retentate with total solid of 6.1355%, salt of 1.3515% and remove 86.15% of the salt from probiotic fermented mung beans concentrate and total LAB counts of 10.73 log cycles. Meanwhile, the permeate obtained at this condition results in flux value of 10.83 Liter/m2.hour with contents of total solid of 6.8199%, salt of 1.325% and total LAB counts of 5.49 log cycles.Keywords: diafiltration, fermented mung beans extract, LAB, probiotic, salt removal, ultrafiltration membran
ADSORPSI ISOTERMAL CO2 BERTEKANAN TINGGI PADA KARBON AKTIF DENGAN METODA VOLUMETRIK
High Pressure Adsorption Isotherm of CO2 on Activated Carbon using Volumetric Method. Adsorption system is ones of the most effective methods for CO2 separating with other substances that produced from the burning of fossil fuels. In the design for that application, beside of characteristics of porous material (adsorbent) data, CO2 adsorptiondata on the adsorbent (kinetic and thermodynamic) are also needed. The aim of this research is resulting isothermal adsorption data at pressures up to 3.5 MPa by indirect methods (volumetric method) at isothermal temperature of 300, 308, 318 and 338 K. Adsorbent that used in this research is activated carbon made from East of Kalimantan coals byphysical activation method (CO2) which is the surface area of activated carbon is 668 m2/g and pore volume is 0.47 mL/g. Carbon dioxide (CO2) that used in this research is high purity carbon dioxide with a purity of 99.9%. Data from the experiment results then correlated using the Langmuir and Toth equations model. The results showed that the maximum adsorption capacity is 0.314 kg/kg at 300 K and 3384.69 kPa. The results of regression of experiment data using Langmuir and Toth models were 3.4% and 1.7%.Keywords: adsorption isothermal, adsorption capacity, Langmuir equation, Toth equatio
ZONASI KARAKTERISTIK KECEPATAN ABRASI DAN RANCANGAN TEKNIK PENANGANAN JALAN LINTAS BARAT BENGKULU BAGIAN UTARA SEBAGAI JALUR TRANSPORTASI VITAL
The Zonation of Abration Speed Characteristics and its Handling Technique of Jalinbar of North Bengkulu as Vital Band Transportation. Jalinbar Bengkulu is a vital infrastructure for traffic service, goods, agriculture products, mining, plantation and oils distribution. Abration due to scour of seawater often make these roads jammed and discrupts the peoples economy movement. The aims of this research was to investigate the abration speed of all segment of Jalinbar. The research method was a combination of two methods: A determination of swash energy of sea water using photometer and determination of rocks binding energy using douche method. The result shows that the maximum abration speed was in north area of Bengkulu beach, occurred in Air Dikit I, Urai I, and Urai II. The abration speed was 2-2,5 m/year. The other abration speed occurred in Air Petai, Palik, Pekik Nyaring in 0,5-1 m/year. On the other hand, Pasar Ketahun, Selolong, Air Serangai I, Air Serangai II, Kota Agung, Ulu Danau and Harapan was 1-2 m/year. The handling technique of all abration location of Jalinbar Bengkulu, north area using groin and jetty, except for Air Dikit and Urai I using jetty. Beside that, the handling technique for Air Serangai II using a combination of groin, jetty, and gabions. Keywords: abration, gabion, groin, jetty, Jalinba
AN INVESTIGATION INTO THE RESISTANCE/POWERING AND SEAKEEPING CHARACTERISTICS OF RIVER CATAMARAN AND TRIMARAN
The increase of fuel price has caused fleet operational and shipping business to be in danger situation. The fuel consumption of a ship is influenced by ship volume or wetted area which contributes directly to the increase of ship resistance and the size of main engine. In order to find out the appropriate answers, a series of investigation into river transportation using monohull, catamaran and trimaran types of vessel was carried out. The work focused on the estimation of total resistance and powering as well as seakeeping characteristics and carried out experimentally using tank test and numerically using a ship design software (Maxsurf). It was found out that the catamaran and trimaran could have less resistance and hence power compared to monohull of similar displacement. The seakeeping characteristics of the multihull vessels were also comparable with those of the monohull. This is a good indication that river catamaran/trimaran is an efficient and comfortable vessel. If a prototype or real vessel is developed, it can be a very efficient ship as well as a ship with high safety standard. Keywords: catamaran, monohull, resistance, seakeeping, trimara
AN EMPIRICAL MODEL FOR BUILD-UP OF SODIUM AND CALCIUM IONS IN SMALL SCALE REVERSE OSMOSIS
A simple models for predicting build-up of solute on membrane surface were formulated in this paper. The experiments were conducted with secondary effluent, groundwater and simulated feed water in small-scale of RO with capacity of 2000 L/d. Feed water used in the experiments contained varying concentrations of sodium, calcium, combined sodiumand calcium. In order to study the effect of sodium and calcium ions on membrane performance, experiments with ground water and secondary effluent wastewater were also performed. Build-up of salts on the membrane surface was calculated by measuring concentrations of sodium and calcium ions in feed water permeate and reject streams usingAtomic Absorption Spectrophotometer (AAS). Multiple linear regression of natural logarithmic transformation was used to develop the model based on four main parameters that affect the build-up of solute in a small scale of RO namely applied pressure, permeate flux, membrane resistance, and feed concentration. Experimental data obtained in a small scale RO unit were used to develop the empirical model. The predicted values of theoretical build-up of sodium and calcium on membrane surface were found in agreement with experimental data. The deviation in the prediction of build-up of sodium and calcium were found to be 1.4 to 10.47 % and 1.12 to 4.46%, respectively.Keywords: build-up, membrane, model, osmosis, wate
THE SYNERGY OF RECOMBINANT XYLANOLYTIC ENZYME ON XYLAN HYDROLYSIS
Microbial xylanases or xylanolytic enzyme have received considerable attention over the last years owing to a multitude of possible applications. These enzymes have potential in the biodegradation of lignocellulosic biomass to fuels, chemicals, fruit juice, animal feed and in improving rumen digestion. More recently, the use of xylanases as bleaching agent in the pulp and paper industry has been suggested to replace of some of the chemicals presently used for this purpose. Such applications could have an important positive impact on the environment. The purpose of this research was determining the synergy of 3 recombinant xylanolytic enzymes (β-xylosidase, exo-xylanase and α-L-arabinofuranosidase) from recombinant Eschericia coli BL21 (DE-star) in xylan hydrolysis by analysis the reduction sugar product. Purified of recombinant xylanolytic enzyme β-xylosidase (Xyl), exo-xylanase (Exo-Xyl) and α-L-arabinofuranosidase (Abfa) with Ni-NTA resin. Seven samples of enzyme (each and enzyme mixture) used to hydrolyze xylan substrate (oat-spelt xylan). Analysis of hydrolysis product was done by HPLC. The xylanolytic activities of this enzyme before and after purification were 0,91 and 9,94 U/mL (Exo-Xyl); 1,65 and 14,2 U/mL (Xyl); 0,65 and 5,6 U/mL (Abfa). The xylosidase activity were 2,37 and 14,3 U/mL (Xyl); 1,49 and 10,5 U/mL (Exo-Xyl); 2,54 and 18,6 U/mL (Abfa). The highest hydrolysis product of xylan (xylose) shown in enzyme mixture of exo-xylanase and β-xylosidase was 1,084 mg/mL. Keywords: α-L-arabinofuranosidase, β-xylosidase, exo-xylanase, xylan, xylos
FORMATION OF CaCO3 PARTICLE AND CONDUCTIVITY OF Na2CO3 AND CaCl2 SOLUTION UNDER MAGNETIC FIELD ON DYNAMIC FLUID SYSTEM
Hard water causes the CaCO3 scale formation on the pipe walls and heat exchanger equipments in industrial or domestic water processes. A great number of experimental researches on the prevention of the CaCO3 precipitation process by magnetic field have been carried out. In this research, Na2CO3 and CaCl2 solutions was magnetized in the circulated flow condition (dynamic fluid system). The velocity of fluid and the circulation time was modified to examine its influences to the magnetization process. CaCO3 content was measured by titration method of EDTA complexometry. Conductivity test was conducted to find out hydrate ion bonding. The results showed that magnetization increased the CaCO3 formation and the optimum process reaches for 10 minutes circulation on 0.554 m/s of flow rate. Magnetic field decreases the conductivities of Na2CO3 and CaCl2 solution, hence reduced the ion hydrate bonding. These results showed that magnetization on Na2CO3 and CaCl2 ionic solution was effective in controlling the CaCO3 formation by increasing CaCO3 precipitation. Keywords: CaCO3 conductivity, magnetic carbonate solution, precipitatio
PRODUCTION OF LOVASTATIN AND SULOCHRIN BY Aspergillus terreus USING SOLID STATE FERMENTATION
Lovastatin is an anti-cholesterol agent that was produced by Aspergillus terreus using solid state fermentation (SSF). During this fermentation process, sulochrin is also produced as an unwanted co-metabolite. However, our previous result showed that sulochrin had potential as antidiabetes because it is an inhibitor agent of α-glucosidase. In this paper, we reported our observation on lovastatin and sulochrin production pattern in relation with inhibitor α-glucosidase activity during eleven days fermentation of A. terreus koji (SSF) ethyl acetate extract. Koji obtained from solid state fermentation with rice as the substrate and incubated at room temperature, sample is taken daily for eleven day (D-1 to D-11). Lovastatin and sulochrin production was measured by Liquid Chromatography- Mass Spectrometer based on their molecular weight m/z 404.5 and 332.3 respectively. The inibitory activity is measured by inhibition model of koji extract against α-glucosidase (EC 3.2.1.20) from Saccharomyces cereviceae. The results show that lovastatin production was started on the day 2 (0.04 mg/g) and achieving the optimal production on day 7 (11.46 mg/g), while sulochrin production was started on day 4 (0.60 mg/g) and keep produced until the end of fermentation period at Day 11 (3.11 mg/g). Koji extract was started to show inhibitory to α-glucosidase activity on Day 5 (IC50= 23.34 μg/mL) and keep showed activity until Day 11 (IC50=3.33 μg/mL). These results suggest that inhibitory activity of koji extract to α- glucosidase activity have relation with sulochrin biosynthesis production.Keywords: α-glucosidase inhibitor, Aspergillus terreus, lovastatin, SSF, sulochri
PENGEMBANGAN PARAMETER TEKNOLOGI TERHADAP PREDIKSI PRODUKTIVITAS PEMBANGUNAN KAPAL DENGAN PENDEKATAN SPLIN KUBIK
Development ofTechnology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach. Ability of production processes associated with state-of-the-art technology, which allows the shipbuilding,is customized with modern equipment. It will give impact to level of productivity and competitiveness. This study proposes a nonparametric regression cubic spline approach with 1 knot, 2 knots, and 3 knots. The application programs Tibco Spotfire S+ showed that a cubic spline with 2 knots (4.25 and 4.50) gave the best result with the value of GCV = 56.21556, and R2 = 94.03%.Estimation result of cubic spline with 2 knots for the PT. Batamec shipyard = 35.61 MH/CGT, PT. Dok & Perkapalan Surabaya = 27.49 MH/CGT, PT. Karimun Sembawang Shipyard = 27.49 MH/CGT, and PT. PAL Indonesia = 19.89 MH/CGT.Keywords: technology parameter, shipbuilding productivity, cubic splin