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STUDI PENENTUAN NILAI RESISTOR MENGGUNAKAN SELEKSI WARNA MODEL HSI PADA CITRA 2D

10.12928/telkomnika.v7i1.571
Didik; Universitas Negeri Yogyakarta Hariyanto
2D image is a form of image which has coordinates x and y, and override the factors of depth (coordinate z). In an image, there is a color information that consisting of components Red, Green, and Blue (RGB). Color information can be used as a medium for a computer program to interpret objects or values as well as the value of resistor color. By using the color information, a resistor value can be count based on bracelet color. To get good results, RGB color model need to be changed to HSI (hue, saturation, Intensity) color model first. Hue value represent the actual color, saturation level indicates the color saturation, and intensity is used to determine the number of light. By using the color selection based on HSI model and determined the value of threshold, it can be used to express the amount of resistor value in the form of a digital image.
Volume: 7
Issue: 1
Page: 13-22
Publish at: 2009-04-01

APLIKASI MOBILE SMS GATEWAY OVER GPRS UNTUK MENGAKSES SISTEM INFORMASI

10.12928/telkomnika.v7i1.575
Wahyu; Universitas Ahmad Dahlan Pujiyono , Arif; Universitas Ahmad Dahlan Rahman , Ananta; Universitas Ahmad Dahlan Wijaya
SMS via GPRS technology can be used to access data from information systems. This technology is one of regular and premium SMS extensions. The SMS over GPRS is composed by three components: the mobile application, server, router and gateway of information systems. The research objective was to build a mobile application to access information systems with the assumption that the server and the gateway router of information systems already exist. System was built using the http protocol, which has a request-response mechanism. There are two methods in the delivery of the message (request) and the receipt of the message (response) from the server, the message filtering and message parsing. Filtering is used to filter the message text /string that not known to be a string known by http, and then in message parsing process, message parses in the form of XML.
Volume: 7
Issue: 1
Page: 43-50
Publish at: 2009-04-01

SOUND OF PADDLE WHEEL ON SEA BASS GROWTH

10.12928/telkomnika.v7i1.570
Sunardi; Universiti Teknologi Malaysia, Universitas Ahmad Dahlan Sunardi , Anton; Universiti Teknologi Malaysia, Universitas Ahmad Dahlan Yudhana , Ahmad Syahril Mohd; Universiti Teknologi Malaysia Nawi , Jafri; Universiti Teknologi Malaysia Din , Saberi; Universiti Teknologi Malaysia Mawi
The objective of this research is sound effect for brackish water for Sea bass (Cynoscion nobilis). Breeding farm 25x100m, 2m of depth, and 6 paddle wheels which generate the sound are available for research. Sound profile has been measured to investigate the amplitude at various measurement points at various depths by using Cetacean hydrophone C304. The output of hydrophone has been analyzed by using SpectraPlus software. For the second measurement, two cages which size 3x3m have been used for life fish habitat. Then, fish put in the edge cage (20), center cage (20), and out of cage (12500). Sound profile has been measured for position-based (edge/center cage), time-based (morning/noon/evening), and point-based. Time series, spectrum frequency, and phase have been analysis. Fish growth progress has been monthly measured at every cage. Fish in the cage is growth as linearly, while fish growth for out of cage is exponentially. Size and weight of fish in the both cages is less than out of cage. This research concludes that sound have no significantly effect for fish growth. Limited mobility to look for food and stress are more influences to fish growth than sound effect.
Volume: 7
Issue: 1
Page: 1-12
Publish at: 2009-04-01

SIMULASI PEMBANGKITAN SINYAL 8–PHASE SHIFT KEYING BERBASIS MATLAB

10.12928/telkomnika.v7i1.574
Indah; Universitas Mercu Buana Yogayakarta Susilawati
Phase Shift Keying (PSK) is simply the allocation of one fixed phase for every code in the bit streams. In BPSK modulation, it’s needed to allocate two distinct phases for “1” and “0”. In QPSK modulation, it’s needed to allocate four distinct phases, each for “01”, “01”, “10”, and “11”. While in 8 – PSK, it’s needed to allocate eight distinct phases, each for “000”, “001”, “010”, “011”, “100”, “101”, “110”, and “111”. Bandwidth efficiency in BPSK is 1 b/s/Hz and 2 b/s/Hz in QPSK. While in 8 – PSK, bandwidth efficiency achieved is 3 b/s/Hz. Higher efficiency bandwidth means narrower bandwidth needed for data transmission.  This simulation is used to generate 8 - PSK signals using Matlab software tools. The results show that the simulation is able to generate BPSK and QPSK signals perfectly.
Volume: 7
Issue: 1
Page: 37-42
Publish at: 2009-04-01

RANCANG BANGUN DIPLEKSER UNTUK PEMANCAR TELEVISI ULTRA HIGH FREQUENCY (UHF)

10.12928/telkomnika.v7i1.578
Trie; Sekolah Tinggi Teknologi Nasional Yogyakarta Handayani
The development of television technology in Indonesia has growth rapidly. This fast growth is marked by the presence of 10 private television stations. Establishing a television station requires a lot of expense especially to build transmitter and tower antenna. This paper presents a research to design and built the diplexer system for merging two transmitter signals transmitted by an antenna transmitter. This design is conducted by using two copper pipes with diameter 3.2 cm and 1.4 cm. The use of different sizes of diameter is intended to obtain impedance characteristic (ZO) equal to 50 Ω. The copper pipe is designed to form a system diplexer with open and close end of transmission. There are two mixing frequency tested, those are 620 MHz ( at terminal A) and 600 MHz (at terminal B). The result shows that terminal A acts as a band pass filter for frequency around 620 MHz and a filter stop band for frequency around 600 MHz . Terminal B acts as a band pass filter for frequency around 600 MHz and as a stop band for frequency around 620 MHz. Based on the results obtained,  this diplexer can be applied to merge two television transmitters with carrier frequency of 600 MHZ and 620 MHz within a single antenna.
Volume: 7
Issue: 1
Page: 65-72
Publish at: 2009-04-01

ANALISIS PENGGUNAAN JARINGAN KABEL LISTRIK SEBAGAI MEDIA KOMUNIKASI DATA INTERNET

10.12928/telkomnika.v7i1.573
Imam; Universitas Mercu Buana Yogyakarta Suharjo
The main function of power network is used to deliver electrical energy to meet energy needs. Although this grid has opportunity to use as line transmission that it was only for analog communication and telemetry originally. In the development of research and technology, this network can be used for digital data communications at speeds high enough. In this study conducted a test of feasibility analysis, especially in the use of electricity for the internet data communication. The low voltage electricity network is used in this research. Results from this study, among the tested electrical network on the short distance of less than 400 meters can be used for data communication with the media either. However, if it is used for a more remote distance, the quality will decrease. The real distance depends to the testing equipment and quality of electricity. 
Volume: 7
Issue: 1
Page: 31-36
Publish at: 2009-04-01

SIMULATOR LENGAN ROBOT ENAM DERAJAT KEBEBASAN MENGGUNAKAN OPENGL

10.12928/telkomnika.v6i3.569
Balza; Universitas Gadjah Mada Achmad , Musthofa; Universitas Gadjah Mada Sunaryo , Agus; Universitas Gadjah Mada Arif
A robot simulator has been developed, that capable in simulating a 6 degree of freedom robot manipulator. Using this simulator, a user can define the type and angular range of the joints, and length of each link, as well as the colors. User can also select an arbitrary viewing angle and move the robot manually or automatically. The simulator was developed using C++ programming language utilizing OpenGL graphic library. Denavit-Hartenberg notation was used as parameters to specify the shape and size of the manipulator.
Volume: 6
Issue: 3
Page: 209-216
Publish at: 2008-12-01

SISTEM PENILAIAN OTOMATIS JAWABAN ESSAY MENGGUNAKAN ONTOLOGI PADA MOODLE

10.12928/telkomnika.v6i3.564
Andi Besse; Institut Teknologi Sepuluh Nopember Surabaya Firdausiah , Daniel; Institut Teknologi Sepuluh Nopember Surabaya Oranova S. , Umi Laili; Institut Teknologi Sepuluh Nopember Surabaya Yuhana , Toshihiro; Institut Teknologi Sepuluh Nopember Surabaya Kita
This paper proposes a combination technique that called hybrid algorithm to be applied into automated scoring for essay e-learning system. This algorithm consists of two main processes: synonym comparison based on WordNet-based semantic similarity measurement and scoring process based on ontology structure. The process for searching a synonym will produce some outputs on different levels. This difference will stimulate a difference calculation of score due to every level reflects to a different similarity of degree. The matching process from input with key answer will generate an accurate matching process. In addition it also added with investigation of ontology class relationship. A different relationship will cause a different score. The last step is integrating this hybrid algorithm and ontology concept into Moodle e-learning system. The evaluation process will evaluate whether the hybrid algorithm can run very well inside ontology system that has been built. Besides that, it is expected that the integration process of hybrid algorithm into Moodle system can support the performance of Moodle e-learning system from essay auto grading perspective.
Volume: 6
Issue: 3
Page: 167-172
Publish at: 2008-12-01

EVALUASI SISTEM PENERANGAN JALAN H.R. SOEBRANTAS KOTA PEKANBARU

10.12928/telkomnika.v6i3.568
Hamzah; Universitas Lancang Kuning Hamzah
The using of road light which is inappropriate for road category and the illegal street light are the two main problem of roadway lighting (PJU). These problems encumber the budget paid by local government (Pemda). Local government paid electric energy for PJU based on the usage of electricity recorded by KWH meter. Meanwhile the payload of the varied roadway lightings without KWH meter will be calculated based on basic monthly rate according to name plate of power and type of the lamp. Local government applies the roadway lighting taxes (PPJU) collected by state company (PLN) from every customers based on percentage of monthly expenses of electricity. Along with the growth of town, there would be more roadways to be illuminated. It will increase the payment of electricity for roadway lighting in every each town and sub-province. This condition would progressively burden the government to settle the expense of electricity for PJU. Therefore, the existing roadway lighting system should be re-evaluated to increase efficiency of electrical usage. In additional, this evaluation will give contribution to save the budget for the roadway lighting electrical payment and with the same existing cost more roadways will get lighting.
Volume: 6
Issue: 3
Page: 199-208
Publish at: 2008-12-01

THE PRELIMINARY RESEARCH FOR IMPLEMENTATION OF IMPROVED DTC SCHEME OF HIGH PERFORMANCE PMSM DRIVES BASED ON FPGA

10.12928/telkomnika.v6i3.563
Tole; Universitas Ahmad Dahlan (UAD) Sutikno
The direct torque control (DTC) is one of control approache that is used commonly in PMSM control system. This method supports a very quick and precise torque response. However, the DTC method is not perfect and has some disadvantages. Many researchers have been proposed to modify the basic DTC scheme for PMSM drive. All this contributions allow performance to be improved, but at the same time they lead to more complex schemes. Furthermore, the PMSM drive control systems are usually based on microcontroller and DSP. Some researchers also have been used DSP and FPGA together to develop DTC for AC drives. These allow improving the performance, but they will increase cost. For the reason above, this paper proposed a new DTC scheme to apply only based on FPGA. The preliminary research showed that the proposed DTC sheme can reduce torque and flux ripples significantly. Therefore, this paper also recomend to realize proposed DTC scheme based on FPGA in order to support to execute very fast computation.The implementation is hoped that it will very potential to replace not only the induction motor but also the DC servo motor in a number of industrial process, commercial, domestic and modern military applications of high-performance drive.
Volume: 6
Issue: 3
Page: 155-166
Publish at: 2008-12-01

SISTEM KENDALI PENJEJAK SINAR MATAHARI DUA LINTASAN KEBEBASAN BERBASIS MIKROKONTROLER AT89C51

10.12928/telkomnika.v6i3.567
Joko; Universitas Ahmad Dahlan Purwono , Muchlas; Universitas Ahmad Dahlan Muchlas , Tole; Universitas Ahmad Dahlan Sutikno
Instalation of solar cell panels permanently will not get maximum power point tracker (MPPT). To get the MPPT, the controlling of solar cell panels are needed in order to follow the direction of sun. In this paper, the design of control system of solar panel that capable to control of solar panel with 2 freedom track based on AT89C51 microcontroller is described. The movement is movement from east to west according to the earth rotation and movement from north to south in according to the earth revolution to get the MPPT. As a result, the prototype of design system has capable to control motor drive of solar cell panel, both automatically and manually with 2-line track to get MPPT.
Volume: 6
Issue: 3
Page: 191-198
Publish at: 2008-12-01

PARAMETER OPTIMIZATION OF PITCH CONTROLLER FOR ROBUST FREQUENCY CONTROL IN AN ISOLATED WIND-DIESEL HYBRID POWER SYSTEM USING GENETIC ALGORITHM

10.12928/telkomnika.v6i3.562
Cuk Supriyadi Ali; Badan Pengkajian dan Penerapan Teknologi (BPPT) Nandar
This paper focuses on the parameter optimization of the pitch controller for robust frequency control in an isolated wind-diesel hybrid power system. The structure of the pitch controller is a practical 1st–order lead-lag compensator. In system modeling, the normalized coprime factorization is applied to represent system uncertainties such as variations of system parameters etc. As a result, the robust stability of the controlled system against various uncertainties can be guaranteed. To obtain the controller parameters, the performance and stability conditions of H∞ loop shaping control are employed to formulate the optimization problem. The genetic algorithm is used to solve the problem. The frequency control effect and robustness of the proposed pitch controller against system uncertainties are evaluated by simulation studies in comparison with a variable structure pitch controller. 
Volume: 6
Issue: 3
Page: 145-154
Publish at: 2008-12-01

DYNAMIC MODELLING OF A FLEXIBLE LINK MANIPULATOR ROBOT USING AMM

10.12928/telkomnika.v6i3.566
Moh. Khairudin; Universitas Negeri Yogyakarta Moh. Khairudin
This paper presents modeling of a flexible link manipulator using Lagrangian technique in conjunction with the assumed mode method (AMM). The links are modeled as Euler-Bernoulli beams satisfying proper mass boundary conditions. A payload is added to the tip of the outer link, while hub inertias are included at the actuator joints. The Lagrangian approach is used to derive the dynamic model of the structure. In this research, the dynamic model of a flexible link manipulator verified using Matlab/Simulink simulation. The model formulation proposed in this work is complete in the sense that it considers the effects of payload and damping structural of the link. The emphasis has been set on obtaining accurate equations of motion that display the most relevant aspects of the coupling between rigid and flexible dynamics.
Volume: 6
Issue: 3
Page: 185-190
Publish at: 2008-12-01

PERANCANGAN LAYANAN SISTEM SELULAR PADA ADAPTIVE CDMA S-ALOHA DENGAN IGA

10.12928/telkomnika.v6i3.565
Hoga; University of 17 AGUSTUS 1945 JAKARTA Saragih
Design of celluler system servicing with adaptive code-division multiple-access slotted-ALOHA (adaptive CDMA S-ALOHA) using improved Gaussian approximation (IGA) was analyzed. In this analysis, the algorithms set of change in the level of transmission speed for user based on the traffic condition occurs. The using of CDMA S-ALOHA channel access protocol is a mix of S-ALOHA and CDMA access methods in wireless communication systems. This method allows the user to access simultaneously, and the using of spectrum is efficient that it is advantages of CDMA S-ALOHA. Adaptive CDMA S-ALOHA method is a technique that can make adjustments based on the level of transmission speed of traffic conditions. As a result, the throughput of adaptive CDMA S-ALOHA based on IGA more accurate than based on Gaussian Approximation (GA).
Volume: 6
Issue: 3
Page: 173 - 184
Publish at: 2008-12-01

COMPARISON OF CURRENT CONTROL METHODS ON CARRIER BASED VSI-PWM INVERTER DRIVES FROM LINE POWER QUALITY ASPECT

10.12928/telkomnika.v6i2.555
Muh. Imran; Universitas Andalas (UNAND) Hamid , Makbul; Universiti Teknologi Malaysia UTM Anwari , Taufik; University San Luis Obispo Taufik
This paper describes simulation result of two methods in current controlling for carrier based VSI-PWM inverter: hysteresis and ramp comparison control.  The simulation useful in selection of ASDs and generally–converter, from power quality point of view. Simulation result show that both ramp comparison and hysteresis control methods  gives difference characteristic on line voltage and line current. A ramp comparison method is better in form of lower effect on line current distortion compare with hysteresis control method. Meanwhile, for line voltage distortion, hysteresis control seen better.
Volume: 6
Issue: 2
Page: 93-100
Publish at: 2008-08-01
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