MAKARA Journal of Technology
Not a member yet
243 research outputs found
Sort by
PENGENALAN ISYARAT TANGAN STATIS PADA SISTEM ISYARAT BAHASA INDONESIA BERBASIS JARINGAN SYARAF TIRUAN PERAMBATAN BALIK
Get PDFStatic Hand Gesture Recognition of Indonesian Sign Language System Based on Backpropagation Neural Networks. The main objective of this research is to perform pattern recognition of static hand gesture in Indonesian sign language. Basically, pattern recognition of static hand gesture in the form of image had three phases include: 1) segmentation of the image that will be recognizable form of the hands and face, 2) feature extraction and 3) pattern classification. In this research, we used images data of 15 classes of words static. Segmentation is performed using HSV with a threshold filter based on skin color. Feature extraction performed with the Haar wavelet decomposition filter to level 2. Classification is done by applying the back propagation system of neural network architecture with 4096 neurons in input layer, 75 neurons in hidden layer and 15 neurons in output layer. The system was tested by using 225 data validation and accuracy achieved was 69%.Keywords: artificial neural networks, feature extraction, hand gesture, segmentation, stati
PENENTUAN NILAI STANDAR DISTORSI BERMINYAK PADA AKUISISI CITRA SIDIK JARI
Get PDFDetermining the Standard Value of the Oily Distortion of Acquisition the Fingerprint Images. This research describes a novel procedure for determining the standard value of the oily distortion of acquisition the fingerprint images based on the score of clarity and ridge-valley thickness ratio. The fingerprint image is quantized into blocks size 32 x 32 pixels. Inside each block, an orientation line, which perpendicular to the ridge direction, is computed. The center of the block along the ridge direction, a two-dimension (2-D) vector V1 (slanted square) with the pixel size 32 x 13 pixels can be extracted and transformed to a vertical 2-D vector V2. Linear regression can be applied to the one-dimension (1-D) vector V3 to find the determinant threshold (DT1). The lower regions than DT1 are the ridges, otherwise are the valleys. Tests carried out by calculating the clarity of the image from the overlapping area of the gray-level distribution of ridge and valley that has been separated. Thickness ratio size of the ridge to valley, it is computation per block, the thickness of ridge and valley obtained from the gray-level values per block of image in the normal direction toward the ridge, the average values obtained from the overall image. The results shown that the standard value of the oily distortion of acquisition the fingerprint image is said to oily fingerprint when the images have local clarity scores (LCS) is between 0.01446 to 0.01550, global clarity scores (GCS) is between 0.01186 to 0.01230, and ridge-valley thickness ratio (RVTR) is between 6.98E-05 to 7.22E-05. Keywords: acquisition, clarity score, distortion, fingerprint image
THE MANUFACTURING PROPERTIES OF GALVANISED STEEL SHEET WITH HEXAGONAL AND TETRAGONAL NETWORK OF CIRCLE HOLES
Get PDFGalvanized steel sheet of 0.8 mm in thickness was drilled with circle holes of 2.5 mm diameter and spacing arranged in tetragonal and hexagonal pattern. The manufacturing properties of specimen were studied through drawing and stretching simulative test. It was concluded from the results that, at high ratio of punch to hole diameter (40/2.5), the drawing properties (LDR) of both square and hexagonal perforated sheet were slightly lower than that of solid sheet, while hexagonal perforated showing LDR somewhat higher than the square one. The stretching properties (LDH) of sheet, however, were much lower than that of solid sheet while the hexagonal perforated exhibiting LDH lower than the square one. Provided the effi ciency factor was well defi ned, which was not effective in the present experiment, the intrinsic drawing properties might be indirectly determined through the simulative test by assuming the perforated materials as an equivalent continuum.Keywords: Circle holes, manufacturing properties, stretching, drawing, galvanized steel
PENGARUH PENAMBAHAN UNSUR 0,25 % Mo PADA BESI TUANG NODULAR YANG DIAUSTENISASI DAN DIAUSTEMPER MENJADI AUSTEMPER DUCTILE IRON TERHADAP SIFAT MEKANISNYA
No full textThe aim of this research is to investigate the effects of 0.25 % Mo (Molybdenum) which is contained in the ductile cast iron on mechanical properties of Austempered Ductile Iron (ADI). The various temperatures and the holding times are used in the heat treatment processes. Using a given 0.25 % Mo in the ductile iron, ADI's alloyed developes a higher ultimate tensile stress value and decreases the elongation if we compare with the as cast (non alloy ductile iron). The higher impact energy value obtained at 9000 C austenization and 375o C austempering temperatures during 60 minutes holding times. The structure changes into ausferrit.Keywords: Heat treatment, holding time, temperature, Ultimate Tensile Strength, Elongation and Impact energ
PENGARUH UNSUR – UNSUR KIMIA KOROSIF TERHADAP LAJU KOROSI TULANGAN BETON : I. DI DALAM AIR RAWA
Get PDFMost of infrastructures using steel concrete to reinforce the strength of concrete. Steel concrete is so vulnerable to chemical compounds that can cause corrosion. It can happen due to the presence of chemical compounds in acid environment in low pH level. These chemical compounds are SO42-, Cl-, NO3-. There are many swamp area in Indonesia. The acid contents and the concentration of ion sulphate, chlorides, and nitrate are higher in the swamp water than in the ground water .The objective ofthis research was to find out the influence of corrosive chemicals in the swamp water to the steel concrete corrosion rate. Therewere two treatment used: (1) emerging ST 37 and ST 60 within 60 days in the 'polluted' swamp water, (2) moving the ST 37 upand down periodically in the ' polluted' swamp water. Three variation of 'polluted' swamp water were made by increasing theconcentration of corrosive chemical up to 1X, 5X and 10X respectively. The corrosion rate was measured by using an Immersion Method. The result of Immersion test showed that chloride had the greatest influence to corrosion rate of ST 37 and ST 60 and followed by sulphate and Nitrate. Corrosion rate value for ST 37 is 24.29 mpy and for ST 60 is 22.76 mpy. By moving the sample up and down, the corrosion rate of ST 37 increase up to 37.59 mpy, and chloride still having the greatest influence, followed by sulphate and nitrate.Keywords : Corrosive ions, swamp water, corrosion rate, steel concret
PADITIF PENINGKAT ANGKA SETANA BAHAN BAKAR SOLAR YANG DISINTESIS DARI MINYAK KELAPA
Get PDFTo reduce NOx, SOx, HC, and particulates that produce because of using diesel fuel, can be done by increasing cetane number. One of methods is adding an additive to diesel fuel. 2-Ethyl Hexyl Nitrate (2-EHN) is a commercial additive that an organic nitrate. Making an additive in this research is used palm oil by nitration reaction that used HNO3 and H2SO4. Result of this reaction is methyl ester nitrate that has a structure looks like 2-EHN. IR spectra from research show that methyl ester nitrate is indicated by spectrum NO2 at 1635 cm-1. This result show that methyl ester nitrate can be synthesized by nitration reaction and yield is 74,84% volume. Loading 1% methyl ester nitrate to diesel fuel can increase cetane number from 44,68 to 47,49.Keywords: Methyl ester nitrate, additive, diesel fuel, palm oi
MODEL OPTIMASI PERENCANAAN INVESTASI GALANGAN KAPAL DENGAN PENDEKATAN PROGRAMASI TUJUAN GANDA
Get PDFOptimation model of planning investment dockyard with approach multi objective goal programming. The purpose of this research is to determine decision variable, goal function, alternative priority and achievement function in investment planning. From this optimation component, the model of ship yard investment planning could be achieved. The model of developed model in this research was the optimation of ship yard investment planning using multi objective goal programming approach. The model consist of 5 decision variable, 11 goal function, 2 alternative priority and 11 achievement functions. The model implementation was done toward PT ASSI investment planning. The calculation using from Quantitative System 3.0 was that the quantity of decision variable parameters could be achieved. The first alternative was based on the difference goal priority, and the second alternative based on similiar goal priority.Keywords: decision variable, goal function, alternative priority, achievement functio
FABRIKASI THIN FILM QUARTERNAIR CuGaSeTe DAN CuGa0.5In0.5Te2 DENGAN EVAPORASI FLASH
Get PDFQuarternair CuGaSeTe and CuGa0.5In 0.5Te2 Thin Films Fabrication Using Flash Evaporation. Quarternairmaterials CuGaSeTe and CuGa0.5In 0.5Te2 are the basic materials to solar cell fabrication. These materials have highabsorption coefficients around 103 - 105 cm-1 and band gap energy in the range of 1-5 eV. In this research, the filmswere made by flash evaporation method using quarternair powder materials of CuGaSeTe and CuGa0.5In 0.5Te2 toadhere in a glass substrate. After the films were obtained, the properties of these films will be characterized opticallyand electrically. The lattice parameter of the films and the crystalline film structure were obtained using X-RayDiffraction (XRD) spectroscopy. The XRD results show that the quarternair CuGaSeTe and CuGa0.5In 0.5Te2 films havea chalcopyrite structure. The absorption coefficient and the band gap energy of the films were calculated usingtransmittance and reflectance patterns that measured using UV-VIS Difractometer. The films composition can bedetected by using the Energy Dispersive Spectroscopy (EDS), while the films resistivity, mobility and the majoritycarrier of the films were obtained from Hall Effect experiments.Keywords: ternair, quarternair, flash evaporation, crystalline lattice parameter, chalcopyrit
STUDI EKSPERIMENTAL ALIRAN SEKUNDER UNTUK AXIAL COMPRESSOR CASCADE STAGGER KUAT DENGAN DAN TANPA TIP-CLEARANCE: DISTRIBUSI TEKANAN STATIS PADA PERMUKAAN BLADE
Get PDFSecondary Flow Experimental Study for Axial Compressor Cascade Strong Stagger With and Without Tip-Clearance: Static Pressure Distribution on Blade Surface. The performance of blade cascade is influenced by thegrowth and boundary layer's separation along blade surface and endwall (casing and hub). The secondary flow whichhappens near hub and casing compressors is three dimentional flow separation phenomenon comes from interactionblade boundary layer with casing and hub boundary layers in the compressor. The secondary flow causes secondarylosses, blockage effect, and turning angle (deflection) distribution along blade span. The result of the research showsthat the increase of the angle of attack reveals lines of constan pressure to be curved forward (upstream) or pressuregives rise to spanwise caused by a strong curl flow. Separation is also increase and cross between two blades. Hence,three dimentional separation region in corner also increase.Keywords: Axial compressor, compressor cascade with and without tip-clearance, curl flow, blockage, tip-clearancevortex, tangential flow
EFFECT OF PHOTOPERIODICITY ON CO2 FIXATION BY Chlorella vulgaris Buitenzorg IN BUBBLE COLUMN PHOTOBIOREACTOR FOR FOOD SUPPLEMENT PRODUCTION
Get PDFTo reduce the level of CO2 content in air, effort on converting CO2 to useful products is required. One of thealternatives includes CO2 fixation to produce biomass using Chlorella vulgaris Buitenzorg. Chlorella vulgarisBuitenzorg is applied for production of food supplement. Chlorella vulgaris Buitenzorg is also easy to handle due to itssuperior adaptation. Currently, Chlorella vulgaris Buitenzorg has been analyzed by some experts for its cellularcomposition, its ability to produce high quality biomass and the content of essential nutrition. A series of experimentswas conducted by culturing Chlorella vulgaris Buitenzorg using Beneck medium in bubbling column photobioreactor.The main variation in this experiment was photoperiodicity, where growth of Chlorella vulgaris Buitenzorg wasexamined during photoperiodicity condition. The difference between CO2 gas concentration of inlet and outlet of thereactor during operational period, was compared to the same experiment under continuous illumination. Underphotoperiodicity of 8 and 9 h/d, the culture cell densities (N) were approximately 40 % higher than under continuousillumination. Final biomass density of Chlorella vulgaris Buitenzorg at 9 h/d illumination was 1.43 g/dm3, around 46%higher than under continuous illumination. Specific carbon dioxide transfer rate (qCO2) in photoperiodicity was 50-80%higher than under continuous illumination. These experiments showed that photoperiodicity affects the growth ofChlorella vulgaris Buitenzorg The specific growth rate (μ) by photoperiodicity was higher than that by continuousilumination while the growth period was two times longer. Based on the experiments, it can be concluded thatphotoperiodicity might save light energy consumption. The prediction of kinetic model under continuous illuminationas well as under photoperiodicity illumination showed that Haldane model became the fitted kinetic model.Keywords: photoperiodicity, Chlorella vulgaris Buitenzorg, food supplement, CO2 fixation, Haldane model