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ANALYSIS, DESIGN AND IMPLEMENTATION OF AN EMBEDDED REALTIME SOUND SOURCE LOCALIZATION SYSTEM BASED ON BEAMFORMING THEORY

10.12928/telkomnika.v7i3.588
Arko; Swiss German University Djajadi , Rusman; Swiss German University Rusyadi , Tommy; Swiss German University Handoko , Maralo; Swiss German University Sinaga , Jürgen; Swiss German University Grueneberg
This project is intended to analyze, design and implement a realtime sound source localization system by using a mobile robot as the media. The implementated system uses 2 microphones as the sensors, Arduino Duemilanove microcontroller system with ATMega328p as the microprocessor, two permanent magnet DC motors as the actuators for the mobile robot and a servo motor as the actuator to rotate the webcam directing to the location of the sound source, and a laptop/PC as the simulation and display media. In order to achieve the objective of finding the position of a specific sound source, beamforming theory is applied to the system. Once the location of the sound source is detected and determined, the choice is either the mobile robot will adjust its position according to the direction of the sound source or only webcam will rotate in the direction of the incoming sound simulating the use of this system in a video conference. The integrated system has been tested and the results show the system could localize in realtime a sound source placed randomly on a half circle area (0 - 1800) with a radius of 0.3m - 3m, assuming the system is the center point of the circle. Due to low ADC and processor speed, achievable best angular resolution is still limited to 25o.
Volume: 7
Issue: 3
Page: 151-160
Publish at: 2009-12-01

PERANCANGAN SISTEM MONITORING ONLINE PADA PASIEN PENDERITA JANTUNG KORONER BERBASIS IDENTIFIKASI SINYAL ELEVASI ST

10.12928/telkomnika.v7i3.592
Ratna; Institut Teknologi Sepuluh Nopember Adil
The coronary heart disease is one of desease leading to the sudden death. This is the reason why online  monitoring system is urgently needed to monitor the patients with coronary heart disease. This paper proposse the system with an algorithm which is developed from signal identification of ST elevation. The medical record in this system is measured by a new wireless ECG development and followed Zigbee standard. If the system detects the possibility of disturbance in cardiac function, then soon, an alarm signal is send to the server at the hospital, in order that an intensive first aid can be given immediately. Based on the testing results, the level of success of an online monitoring system is possible to reach 100% if the patient does not make any moving around. It is expected that the application of this system will reduce the sudden death for patients at hospital with coronary heart disease.
Volume: 7
Issue: 3
Page: 181-186
Publish at: 2009-12-01

DEVELOPMENT OF A CURRENT CONTROL ULTRACAPACITOR CHARGER BASED ON DIGITAL SIGNAL PROCESSING

10.12928/telkomnika.v7i3.587
Ahmad Saudi; Universitas Lampung Samosir
Ultracapacitor usually use as a short-term duration electrical energy storage because it has several advantages, like high power density (5kW/kg), long lifecycle and very good charge/discharge efficiency. Unlike batteries, ultracapacitors may be charged and discharged at similar rates. This is very useful in energy recovery systems such as dynamic braking of transport systems.  Here are a few characteristics of ultracapacitors that should be kept in mind when integrating/designing a charging system for the intended application. An ultracapacitor with zero charge looks like a short circuit to the charging source. Most of low cost power supplies fold back the output current in response to a perceived short circuit, making them unsuitable for charging of ultracapacitors. Ultracapacitors have a low series inductance allowing easy stabilizing with switch mode chargers. The RC time constant of passive charging networks is usually too long. Therefore, linear regulators are inefficient components for ultracapacitor charging. In this paper, the development of a current control ultracapacitor charger based on Digital Signal Processing (DSP) is presented. 
Volume: 7
Issue: 3
Page: 145-150
Publish at: 2009-12-01

PURWARUPA ROBOT PEMADAM API DENGAN SENSOR ULTRASONIC DAN ULTRAVIOLET BERBASIS AT89S52

10.12928/telkomnika.v7i3.596
Wahyu Sapto; Universitas Ahmad Dahlan Aji , Fajar; Universitas Ahmad Dahlan Hermawanto , Muchlas; Universitas Ahmad Dahlan Muchlas
The fire often takes many victims. Fire detection system sometime can not prevent this from happening. Therefore, it is essential to develop a robot that can detect the present of fire as well as extinguish it. This research aimed to design a fire extinguisher robot using AT89S52 microcontroller as its controller. A DC fan controlled by a relay is utilized to put out the fire and a fire sensor (UV-Tron) is used to detect the presence of fire. The movement of the robot is driven by motor DC. The robot can detect the surrounding obstacles and possess an ultrasound-based navigation system. If the ultrasound system detects an obstacle, the robot will automatically turn without colliding the obstacle or other things around it. The result has shown that this fire extinguisher robot can be built using hardware and software controlled by an AT89S52 microcontroller. It can be concluded from the tests that the robot can detect fire as far as 5 meter distance and able to successfully put out the fire.
Volume: 7
Issue: 3
Page: 207-212
Publish at: 2009-12-01

PENCARIAN JALUR ALTERNATIF PADA DAERAH BENCANA LUMPUR SIDOARJO DENGAN METODE ANALYTIC HIERARCHY PROCESS BERBASIS WAP

10.12928/telkomnika.v7i2.586
Arna; Politeknik Elektronika Negeri Surabaya Fariza , Afrida; Politeknik Elektronika Negeri Surabaya Helen , Ardinur; Politeknik Elektronika Negeri Surabaya Mahyuzar
In line with the increasing interest on Lapindo mud disaster which causes several roadway covered by mud, there is a need to give an alternative solution for traffic transportation problem in surrounding area. The possible criteria for the solution of this road way are length, surface, traffic, and width of the road. Types of vehicle across the road also give a contribution to the criteria. By using Geography Information System (GIS), it is easy to all drivers to take decision which way has to be chosen based on the real condition. GIS is used to visualize the alternative road, which is possible to take. Analytic Hierarchy Processing (AHP) is a decision method which is based on many criteria and alternatives. The input of AHP can be a preference or real value. Applied AHP to decide value of each alternative is based on application of Wireless Application Protocol (WAP) assessment.
Volume: 7
Issue: 2
Page: 137-144
Publish at: 2009-08-01

KOMBINASI FEED BACK DAN FEED FORWARD KONTROLLER PI SEBAGAI KENDALI DYNAMIC VOLTAGE RESTORER (DVR) UNTUK MEMULIHKAN VOLTAGE SAG DAN INTERRUPTION

10.12928/telkomnika.v7i2.581
Dimas; Institut Teknologi Sepuluh Nopember Anton A , Imron; Institut Teknologi Sepuluh Nopember Rosyadi , Mochamad; Institut Teknologi Sepuluh Nopember Ashari , Heri; Institut Teknologi Sepuluh Nopember Suryoatmojo
Dynamic voltage restorer (DVR) is one of equipments to protect sensitive load from voltage drop. DVR is installed series with line feeder by serial transformer which injecting voltage when under voltage occurs. This research is investigate the capability of DVR, which controlled by combination of feed back and feed forward PI, to handle voltage sag and interruption. DVR controls have been designed and implemented in DVR prototype. As a result, in simulation, DVR can maintain voltage in range 90% - 105% nominal voltage. Voltage at load side can be restored to 1 pu and 0.79 pu when voltage sag and interruption respectively. Furthermore, DVR prototype can restore 0.95 pu when voltage sag and 0.54 pu when interruption.
Volume: 7
Issue: 2
Page: 93-102
Publish at: 2009-08-01

SIMULASI PERHITUNGAN HIGH POWER AMPLIFIER PADA SISTEM VSAT

10.12928/telkomnika.v7i2.585
Indri; Politeknik Negeri Jakarta Neforawati , Hoga; University of 17 Agustus 1945 Jakarta Saragih
Arithmatical simulation of High Power Amplifier (HPA) on VSAT system is a program which used  to calculate the capacity of HPA as a working test of maximum power on each remote station of the VSAT network system, afterward  can be obtained the available  capacity value and power capacity used, therefore  able to reallocate residual power below its available power spare. VSAT system can be used for several telecommunication application such as video broadcast, data broadcast,audio broadcast, banking operation, ATM and others. Due to the easy operational, maintanance and its instalment, VSAT system is more prifitable compare to ordinary terestrial band, its capability for  multiservice application become more  flexible in using  its network. The software used is Visual Basic 6.0 version and database Microsoft Access. These software take a role as visualization and planning for remote station development and also power capasity needed for each remote in the calculation of HPA. 
Volume: 7
Issue: 2
Page: 129-136
Publish at: 2009-08-01

KERAMIK PORSELEN BERBASIS FELDSPAR SEBAGAI BAHAN ISOLATOR LISTRIK

10.12928/telkomnika.v7i2.580
Eva; Universitas Diponegoro Indiani , Ngurah Ayu Ketut; Universitas Diponegoro Umiati
Electric solid insulator based on ceramics porcelain had been made by using local raw materials: 68% feldspar, 10% kaolinite and 22% quartz, and also added 0%, 5%, 10%, 15%, 20%, 25% cullet (From total mass). The forming process of the porcelain was conducted by milling the raw materials using ball mill and screened using 200 mesh screening. The samples were formed by using the dry-press method with the pressure of 50MPa, then the samples is sintered at temperature of 1000oC, 1050oC, 1100oC, 1150oC for 2 hours. The properties of the samples had been analyzed for their  shrinkage, density, bending strength and resistivity. The result of the experiment showed that the optimum value was reached by ceramic which was added by 15% cullet and sintered at temperature of 1100oC. This ceramic had shrinkage of 9,70%, density of 2,44 g/cm3, bending strength of 86,73 MPa and the resistivity at 25oC is 2,32x108 Ωcm
Volume: 7
Issue: 2
Page: 83-92
Publish at: 2009-08-01

SISTEM INFORMASI VIA SMS GATEWAY ANTARA PIHAK KEPOLISIAN DENGAN PENGEMUDI

10.12928/telkomnika.v7i2.584
Ratna; Politeknik Elektronika Negeri Surabaya – Institut Teknologi Sepuluh Nopember Adil
Sum up accident sacrifice at January period of up to August 2007 progressively mount and primary factor of cause the happening of accident is human being factor, one of them is missing driver of awareness. To lessen this accident number, one of them is earn conducted by killing car machine in order to the missing driver of awareness cannot animate its car machine as well as communications with party police. The making of information system via SMS Gateway of between party police with driver, expected to by earn to overcome the problem. In this system, there are two sides that is side of driver and side police. Data of co-ordinate of position vehicle taken by GPS then is delivered through SMS of through server/police. That Data co-ordinate then is presented at digital map. Data of number Vehicle delivered through SMS to server and kept in database. With exploiting technology GPS (Global Positioning System), Microcontroller, GSM Modem, MapInfo, and Microsoft Office Access for the data intake, conducted a examination several times in place which equal to time difference about minute half, so that be got by a difference apart between position result of examination with data of reference of Google Earth of equal to more or less one meter. Others also be happened by the data deviation between position got from intake of data GPS with position vehicle which in fact (reference data from Google Earth). The based on result of examination which have been conducted in place location park D3 PENS ITS differ from position vehicle which in fact and happened by the position deviation more or less four transversal meter on course south (- 7,165614°) and the east longitude (112,476011°).
Volume: 7
Issue: 2
Page: 119-128
Publish at: 2009-08-01

A NOVEL APPROACH FOR CONFIGURING THE STIMULATOR OF A BCI FRAMEWORK USING XML

10.12928/telkomnika.v7i2.579
Indar; Petra Christian University Sugiarto
In a working BCI framework, all aspects must be considered as an integral part that contributes to the successful operation of a BCI system. This also includes the development of robust but flexible stimulator, especially the one that closely related to the feedback of a BCI system. This paper describes a novel approach in providing flexible visual stimulator using XML which has been applied for a BCI (brain-computer interface) framework. Using XML file format for configuring the visual stimulator of a BCI system, we can develop BCI applications which can accommodate many experiment strategies in BCI research. The BCI framework and its configuration platform is developed using C++ programming language which incorporate Qt’s most powerful XML parser named QXmlStream. The implementation and experiment shows that the XML configuration file can be well executed within the proposed BCI framework. Beside its capability in presenting flexible flickering frequencies and text formatting for SSVEP-based BCI, the configuration platform also provides 3 shapes, 16 colors, and 5 distinct feedback bars. It is not necessary to increase the number of shapes nor colors since those parameters are less important for the BCI stimulator. The proposed method can then be extended to enhance the usability of currently existed BCI framework such as BF++ Toys and BCI 2000.
Volume: 7
Issue: 2
Page: 73-82
Publish at: 2009-08-01

ANALISIS SIFAT HIDROFOBIK PERMUKAAN HDPE BERDASARKAN NILAI TOTAL HARMONIC DISTORTION

10.12928/telkomnika.v7i2.583
Abdul; Universitas Diponegoro Syakur , Hermawan; Universitas Diponegoro Hermawan , Sarjiya; Universitas Gadjah Mada Sarjiya , Hamzah; Universitas Gadjah Mada Berahim
Polymer material has been developed to replace the porcelain insulator material and glass. When it is used as outdoor insulator, environmental conditions have a significant influence to the value of surface discharge current, especially for the coastal area and industry. Salt, dust and chemicals contaminant are suspected as the causes of initial current of surface discharge and the insulator surface degradation which lead to a flashover. To analyze the performance of the insulator surface when the leakage current occurs, the Total Harmonic Distortion (THD) is needed to be determined. The value of THD leakage current indicates the hydrophobic characteristic of surface material. This paper analyzes the results of leakage current measurement in laboratory-scale based on IEC 587:1986 with Inclined-Plane Tracking (IPT) method to the High Density Polyethylene (HDPE) polymer material which is provided in smooth and rough surface. The testing voltage is 50 Hz AC. Data of leakage current magnitude values cover its maximum average as a function of time and the result of FFT to the wave form of the leakage current. As the result, the value of percentage THD decrease as the function of time. The smooth surface material has THD value 43.42% and the rough surface has 15.89%.
Volume: 7
Issue: 2
Page: 109-118
Publish at: 2009-08-01

PURWARUPA SISTEM PEMBATAS KECEPATAN SEPEDA MOTOR BERBASIS MIKROKONTROLER AT89S52

10.12928/telkomnika.v7i2.582
Ikhsan; Universitas Ahmad Dahlan hidayat , Abdul; Universitas Ahmad Dahlan Fadlil , Edy; Universitas Ahmad Dahlan Fathurrozaq
Security riding is very important in the aspects of traffic. One of the main factors of traffic accidents is high speed. Therefore, it is required a speed restraint equipment for pressing the number of accidents. The car speed restraint system is available in the market, but on a motorcycle is not available yet. This paper presents a design of speed restraint equipment for motorcycle that safe for users, and is expected to reduce traffic accident. The Main idea this speed restriction is cutting off the flow of electrical signals from the pulser (the time ignition trigger sensor) to the CDI for 1 second. The cutting Signal with mechanical relays controlled by microcontroller AT89S52 using the on-off algorithm. Speed sensor use optocoupler is used to detect the number of rounds wheel motorcycle. If a result of measurement is more than the speed setpoint, microcontroler make a decission to cut motorcycle ignition signal. Results of this research is a prototype speed restraint shown that it able to process data from the measurement of the speed limit on the speed of a motorcycle. This prototype safe for all users and accordance with the set value and the level of success is above 90% for speed of 10 km/hr to 40 km/hr.
Volume: 7
Issue: 2
Page: 103-108
Publish at: 2009-08-01

IMPLEMENTASI MIKROKONTROLER SEBAGAI PENCACAH FREKUENSI BERBASIS PENGUKURAN PERIODE ISYARAT MASUKAN

10.12928/telkomnika.v7i1.577
Freddy; Sekolah Tinggi Teknologi Adisutjipto (STTA) Kurniawan
One of the main components from frequency counter is a processor. This processor must have ability to conduct counting and arithmetical calculation. To get competitive price, in this research a microcontroller is applied as a processor. This paper presents design of frequency counter based on microcontroller AT89S51 which has two independent timers. The input frequency counter is conducted by using facilities inside microcontroller e.g. T0 and external interruption. Counter method used in this research is by measuring input signal period. This method is proven effectively to count frequency especially low frequency. As the result, the frequency counter has successfully measured frequency from 0.1 until 10 kHz with maximum error 1%. This device is possible to be the next frequency counter with competitive price.
Volume: 7
Issue: 1
Page: 57-64
Publish at: 2009-04-01

MATLAB/SIMULINK BASED ANALYSIS OF VOLTAGE SOURCE INVERTER WITH SPACE VECTOR MODULATION

10.12928/telkomnika.v7i1.572
Auzani; Universiti Teknikal Melaka Malaysia (UTeM) Jidin , Tole; Universitas Ahmad Dahlan (UAD) Sutikno
Space vector modulation (SVM) is the best modulation technique to drive 3-phase load such as 3-phase induction motor. In this paper, the pulse width modulation strategy with SVM is analyzed in detail. The modulation strategy uses switching time calculator to calculate the timing of voltage vector applied to the three-phase balanced-load. The principle of the space vector modulation strategy is performed using Matlab/Simulink. The simulation result indicates that this algorithm is flexible and suitable to use for advance vector control. The strategy of the switching minimizes the distortion of load current as well as loss due to minimize number of commutations in the inverter.
Volume: 7
Issue: 1
Page: 23-30
Publish at: 2009-04-01

PENINGKATAN KECEPATAN PROSES PADA METODE COLOR ORDERING DAN MAPPING DENGAN PENDEKATAN DELAPAN-KETETANGGAAN

10.12928/telkomnika.v7i1.576
Astried; Universitas Riau Astried , Tri Basuki; Universitas Bina Darma Kurniawan
The development of digital technology and internet, nowadays, has given the facility for easy access and distribution of a lot of information in digital form. The facilities in distributing digital data also has emerged the negative impact such as the violence of copy right. One of techniques developed from negative impact is water making technique. Several techniques have been mentioned by many researches in water making, one of them is the use of color palette and color index which is also know as ordering and mapping color method. In this method, the substitute color found through all colors in the pallets so this process gives the longer time in bit watermark inserting process. In this paper, ordering and mapping color which use color pallet of an image will be modified to increase the speed of the process by using eight neighborhoods approximation. From experimental result conducted to 30 images, it can be concluded that the proposed approximation has taken the shorter time than the conventional method. 
Volume: 7
Issue: 1
Page: 51-56
Publish at: 2009-04-01
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