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IPTEK The Journal for Technology and Science
Published by Institut Teknologi Sepuluh Nopember Surabaya
ISSN : 08534098     EISSN : 20882033     DOI : -
Core Subject : Science,
Computer Science & IT
IPTEK The Journal for Technology and Science (eISSN: 2088-2033; Print ISSN:0853-4098), is an academic journal on the issued related to natural science and technology. The journal initially published four issues every year, i.e. February, May, August, and November. From 2014, IPTEK the Journal for Technology and Science publish three times a year, they are in April, August and December in online version.
Arjuna Subject : -
Articles 345 Documents
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A Comparative Study of Water Quality Characteristics at East Java River Sri Wahyuningsih; Nadjadji Anwar; Edijatno Edijatno; Nieke Karnaningroem
IPTEK The Journal for Technology and Science Vol 21, No 4 (2010)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v21i4.91

Abstract

Water is the natural resources have the function of very importance for human life and also as authorized capital in development. Water will influence by the other component. Exploiting of water to support all human life must done with wise action to management so that not result damage at water resource. As place relocation of water hence river have the selected capacities that able to change because natural activity and antropogenik. This research was conducted in nine major rivers in East Java. The objectives of this study were: 1) Identifying the characteristics and concestration range of water quality parameter, 2) Comparison the level of pollution in rivers in East Java. The results of this study indicated that the characteristic of water quality parameter of rivers in East Java were generally physical, chemical and biological. The comparison result of water quality parameter basically showed that in general the pH was still under threshold that had been determined, that was pH from 6 to 9. In general, DO concentration ranged from 0.5 mg/l to 7 mg/l, BOD concentration ranged from 3 mg/l to 11 mg/l and the COD concentration ranged between 0.5 mg/liter to 35 mg/l.
Performance Test with TiO2 Modified Activated Carbon on Pilot Scale Phenol Removal Slamet Slamet; Ade Putera; Setijo Bismo
IPTEK The Journal for Technology and Science Vol 19, No 4 (2008)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v19i4.143

Abstract

The integrated of activated carbon adsorbent and TiO2 photocatalyst (TiO2/AC) has been synthesized and evaluated to remove phenol in the continuous pilot scale system. TiO2/AC was prepared by mixing of AC into sol system consisting of TiO2 Degussa P-25, water, and tetraehtyl orthosilicate (TEOS) solution as a source of silica. The mixtures then evaporated at ±97oC and calcined at 400oC. Performance test of the material was conducted using Tubular-V-Collector (TVC) reactor that equipped with 14 UV black light lamps. The experimental results show that the phenol could effectively be removed through simultaneous adsorption and photocatalysis. Within the residence time of 6 minutes, TiO2/AC could continuously remove the 50 ppm of phenol by 100% phenol removal as long as 5 hours.
Advanced DVR with Zero-Sequence Voltage Component and Voltage Harmonic Elimination for Three-Phase Three-Wire Distribution Systems Margo P; Mauridhi Heri Purnomo; Mochamad Ashari; Zaenal P; Takashi Hiyama
IPTEK The Journal for Technology and Science Vol 20, No 4 (2009)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v20i4.21

Abstract

Dynamic Voltage Restorer (DVR) is a power electronics device to protect sensitive load when voltage sag occurs. Commonly, sensitive loads are electronic-based devices which generate harmonics. The magnitude and phase of compensated voltage in DVR depend on grounding system and type of fault. If the system is floating, the zero sequence components do not appear on the load side. Meanwhile, in a neutral grounded system, voltage sag is extremely affected by zero sequence components. A blocking transformer is commonly installed in series with DVR to reduce the effect of zero sequence components. This paper proposes a new DVR control scheme that is capable of eliminating the blocking transformer and reducing harmonic distortion. The system uses fuzzy polar controller to replace the conventional PI or FL controller that is commonly used. By taking into account the zero sequence components in the controller design, the effects of zero sequence components can be compensated. Simulated results show the effectiveness of the proposed DVR controller
The Physical Treatment Soil Characteristics for Grounding Systems on Madiun and Surabaya Region Bambang Anggoro; Ngapuli I. Sinisuka; Parouli M. Pakpahan; Dicky I. B.
IPTEK The Journal for Technology and Science Vol 18, No 1 (2007)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v18i1.176

Abstract

The research on soil characteristic by measuring soil resistancy and resistivity is an important factor to make a good grounding impedance. The optimal evaluation and planning of the grounding system can be achieved by understanding the soil structure and characteristic. The soil resistivity varies upon soil composition, temperature, water content and its chemical content. In this research we analyse soil characteristics of the samples from Madiun and Surabaya areas by conducting some physical treatments such as water, salt, and carbon treatments. These samples then are tested using 0Hz – 15MHz frequency from sinusoidal power supply. Generally, soil impedance has a negative correlation upon addition of water and salt content, but has no correlation upon additional carbon content.
Wind-Electric Power Potential Assessment for Three Locations in East Java-Indonesia Ali Musyafa; I Made Yulistya Negara; Imam Robandi
IPTEK The Journal for Technology and Science Vol 22, No 3 (2011)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v22i3.71

Abstract

This paper reports our effort to asses wind energy potentials for three locations in East Java. We used wind speed data over a period of almost 3 years, i.e. in period of June 2006 – August 2008. Data were taken from direct measurement in locations in East Java Province, i.e. Sampang (Madura), Juanda (Surabaya), and Sawahan (Nganjuk). The short-term of wind speed mean in monthly signifies to wind-speed value ”which parallels to the wind turbine power curve value” were used to estimate the annual energy output for a 1 MW installed capacity wind farm on the each site 100 of 10kW rated wind turbines were used in the analysis. The short term of wind speed mean at Surabaya and Nganjuk were 2.34, 3.03 and 1.97 m/s at 2 m Above Ground Level (AGL), respectively. In both locations, wind speeds were observed during the day time between 04.00 and 18.00 and relatively smaller ones between 19.00 and 03.00 period. Meanwhile, in Sampang (Madura) the higher wind speeds were observed between 20.00 and 06.00, and relatively smaller between 07.00 and 19.00 period. The 1 MW windfarm at Sampang, Surabaya and Nganjuk can produce 1.284; 1.199 and 1.008 MWh of electricity yearly, taking into consideration of the temperature adjustment coefficien of about 6 %. The plant capacity factor at Sampang, Surabaya and Nganjuk were found to be 30.02 %, 30.00 % and 30.01 % respectively. Additionally, it is noticed that these site can contribute to the avoidance of 0.904; 0.846 and 0.709 tons/year of CO2 equivalent Green House Gases (GHG) from entering into the local atmosphere, thus creating a clean and healthy athmosphere for local inhabitants.
The Analysis of Wafe Refraction using SWAN Model Sujantoko Sujantoko
IPTEK The Journal for Technology and Science Vol 20, No 2 (2009)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v20i2.123

Abstract

Wave simulation is important problem in nearshore coastal design process. Determination of proper wave parameter will provide reliable and accurate design, therefore modeling usually needed to simulate this process where numerical model is the right choice because of its cost is cheaper and the result is quite accurate. SWAN (Simulating Wave Nearshore) is numerical model that already used widely to simulate wave in coastal area. In this research we analyze wave refraction by SWAN model with any coastal profile (m) i.e. 0,01 , 0,03 and 0,05. This simulation also applied in the real problem at Tegal port in Central Java Province. According to the result of this model we find that in the same direction, height, and period, the height of wave break will increase as the coastal slope increase. These problems arise due to decreasing in value of db/Hb that means the peak wave is become steep. Coastal Profile affect the wave height (duo to refraction) about 2%-34%. The jetty at Tegal Port induce the wave height big alteration at dock pond (228,91%) at wave direction 30o, while at groove, back and head of the jetty, wave reduction reach until 12,96% ; 0,02% and 3,55% at incoming wave direction 45o. In the head of the jetty, the wave almost doesn’t being reduced because diffraction and wave reflection doesn’t have significant effect.
Numerical Study Characteristics of Heat Transfer on Staggered Cylinder Arrangement Sulharman, Sulharman; Setiawan, M. Yasep
IPTEK The Journal for Technology and Science Vol 23, No 3 (2012)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v23i3.5

Abstract

This research was conducted to examine the characteristics of heat transfer and heat flux fluctuations of staggered cylinder arrangement. The parameters in this study is Reynolds 8.8x104 , inlet velocity of 1 m/s and inlet temperature of 600C. Numerical model used is a 2D model-URANS turbulence model is k-omega SST. The results of this study indicate that increased flow velocity in the narrow area on the second row and third row caused by the staggered arrangement. This led to the distribution of the local Nusselt third highest row two and row after row of the lowest. Highest temperature distribution found in the area and the intensity of the turbulent wake in the third row higher value this is due to the influence of turbulence on the previous line and the arrangement of the cylinders. Effect of heat flux variation of the average Nusselt number appears lower in the heat flux 600 W/m2 than 200 W/m2 and 1000 W/m2 , but the third row average Nusselt values coincide with each other. While the average turbulent intensity increases towards the downstream. In the third row with a heat flux of 600 W/m2 has the highest turbulence intensity, while for the heat flux and heat flux of 200 W/m2 1000 W/m2 intensity turbulennya coincide with each other.
Isolation of Molds for Reducing the Color of Vinase Kurniawan, Yahya; S. M., Hendro
IPTEK The Journal for Technology and Science Vol 19, No 1 (2008)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v19i1.160

Abstract

Vinase or ethanol slop is blackish brown liquid, which is not friendly to the environment. Therefore, it is necessary the possibility to reduce the color biologically. The study was started by isolating molds from the vinase of Jatiroto Alcohol factory and the isolated molds was tested to study the capability of their color reduction. The results showed that there were 4 kinds of molds in the vinase i.e. : Rhizopus sp., Penicillium A, Penicillium B, and Aspergillus. Amongst these molds, Penicillium A and Penicillium B had the best potency in reducing the slop color. Around 54 % of its absorbency value at 420 nm could be reduced by the molds.
Effect of Particle Size Distribution on Ammonium Sulphate Dried in a Rotary Dryer Susianto, Susianto; Altway, Ali; Kuswandi, Kuswandi; Margono, Margono
IPTEK The Journal for Technology and Science Vol 21, No 3 (2010)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v21i3.37

Abstract

The aim of this work is to study theoretically, by mathematical model development, the effect of particle size distribution on the performance of rotary dryer to dry ammonium sulphate fertilizer assuming plug flow with axial dispersion pattern (PFDA model) for solid particle flow. The mathematical model development was carried out by combining the drying processes model with particle size distribution model. Particle size distribution models used are Rosin-Rommler model and Gamma distribution model. For simplicity, the model of drying processes of solid particles in the rotary dryer was developed by assuming of uniform air conditions (temperature and humidity) along the rotary dryer as in the entry conditions. The resulting differential equations were solved analytically under Matlab 6.1 facility.Since this model, solid hold up, and axial dispersion number were obtained from empirical correlations in the literatures. The drying rate of ammonium sulphate fertilizer in rotary dryer was estimated using isothermal diffusion model with effective diffusivity of moisture in the particle obtained from previous study [2]. Using Gamma function distribution, this research showed that for the value of the coefficient of variance (CV) less than 0.5, particle size distribution does not have significant effect on dryer performance. For the value of CV greater than 0.5, the dryer performance increase (or outlet solid moisture content decrease) with increasing the value of CV. The application of Rosin-Rammler model gives lower prediction of outlet solid moisture content compared to the application of Gamma function model.
Multi-Objective Two-Dimensional Truss Optimization by using Genetic Algorithm Alrasyid, Harun; Aji, Pujo
IPTEK The Journal for Technology and Science Vol 22, No 2 (2011)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v22i2.62

Abstract

During last three decade, many mathematical programming methods have been develop for solving optimization problems. However, no single method has been found to be entirely efficient and robust for the wide range of engineering optimization problems. Most design application in civil engineering involve selecting values for a set of design variables that best describe the behavior and performance of the particular problem while satisfying the requirements and specifications imposed by codes of practice. The introduction of Genetic Algorithm (GA) into the field of structural optimization has opened new avenues for research because they have been successful applied while traditional methods have failed. GAs is efficient and broadly applicable global search procedure based on stochastic approach which relies on “survival of the fittest” strategy. GAs are search algorithms that are based on the concepts of natural selection and natural genetics. On this research Multi-objective sizing and configuration optimization of the two-dimensional truss has been conducted using a genetic algorithm. Some preliminary runs of the GA were conducted to determine the best combinations of GA parameters such as population size and probability of mutation so as to get better scaling for rest of the runs. Comparing the results from sizing and sizing– configuration optimization, can obtained a significant reduction in the weight and deflection. Sizing–configuration optimization produces lighter weight and small displacement than sizing optimization. The results were obtained by using a GA with relative ease (computationally) and these results are very competitive compared to those obtained from other methods of truss optimization.

Page 19 of 35 | Total Record : 345

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