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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

PERANCANGAN EARTH LEAKAGE CIRCUIT BREAKER DENGAN SENSIVITAS 20 MA

10.12928/telkomnika.v6i2.559
Pandung; Universitas Negeri Papua Sarungallo , Adelhard Beni; Universitas Negeri Papua Rehiara
Electrics current can flow out to the ground by using a human body. This electric current will be dangerous to the human when it exceed 20mA. A very sensitive earth leakage circuit breaker (ELCB) is needed to anticipate the leaky current but most of ELCB can only be found in the market with sensitivitas 30mA or bigger. This research is succees to design an ELCB with sensitivity 20mA. Characteristic of an ELCB is very influenced by the current transformer characteristic and the relay which are used.
Volume: 6
Issue: 2
Page: 125-130
Publish at: 2008-08-01

OPTIMALISASI DESAIN KENDALI KECEPATAN PUTAR MOTOR INDUKSI TIGA FASA BERBASIS FPGA

10.12928/telkomnika.v6i2.554
Tole; Universitas Ahmad Dahlan Sutikno
FPGA based the problem of implementation of PWM signal generating system is solution of transformation to digital gate logic space. These stages are done with sampling, quantizing and coding. Best resolution of sampling and carrier frequency, so result of PWM generating is better, but it required most digital gate. Aim of this research is optimization of last research adjustable speed drive of three-phase induction motor; with improve resolution of sampling and carrier frequency, and minimalization of digital gate used with Quine Mc Cluskey method. Result of this research indicate that the design of optimalized SPWM generating signal can be realized in hardwared-logic in ACEXIK FPGA to drive inverter as speed controller turn around the three phase induction motor, with requiring 1629 logic cell. Adjustable motor speed designed can be done by through setting make a modulation index and frequency. At this research, system have been tested at setting frequency 3-50 Hz with the variation of modulation index, and can adjustable three phase induction motor speed in  range  117-1468 rpm.
Volume: 6
Issue: 2
Page: 83-92
Publish at: 2008-08-01

RANCANGAN INFRASTRUKTUR E-BISNIS BUSINESS INTELLIGENCE PADA PERGURUAN TINGGI

10.12928/telkomnika.v6i2.558
Spits; Universitas Budi Luhur Warnars H.L.H
In order to compete with others, high education need complete their infrastructure with Information technology support. High level management as a decision maker needs something that can boost the system to compete with other high education. They need IT knowledge that can support them to view the future and can help the whole system to improve their services. Business Intelligence is one of term of Decision Support System which can help the management by something that they can forecast and decide. High Education needs infrastructure design to make good foundation for business intelligent implementation which will be implemented on internet or e-business.
Volume: 6
Issue: 2
Page: 115-124
Publish at: 2008-08-01

DEVELOPMENT OF FUZZY LOGIC CONTROL FOR VEHICLE AIR CONDITIONING SYSTEM

10.12928/telkomnika.v6i2.553
Henry; University Gadjah Mada Nasution
A vehicle air conditioning system is experimentally investigated. Measurements were taken during the experimental period at a time interval of one minute for a set point temperature of 22, 23 and 24oC with internal heat loads of 0, 1 and 2 kW. The cabin temperature and the speed of the compressor were varied and the performance of the system, energy consumption and energy saving ware analyzed. The main objective of the experimental work is to evaluate the energy saving obtained when the fuzzy logic control (FLC) algorithm, through an inverter, continuously regulates the compressor speed. It demonstrates better control of the compressor operation in terms of energy consumption as compared to the control by using a thermostat imposing On/Off cycles on the compressor at the nominal frequency of 50 Hz. The experimental set-up consists of original components from the air conditioning system of a compact passenger vehicle. The experimental results indicate that the proposed technique can save energy and improve indoor comfort significantly for vehicle air conditioning systems compared to the conventional (On/Off) control technique.
Volume: 6
Issue: 2
Page: 73-82
Publish at: 2008-08-01

SISTEM INFORMASI PERPUSTAKAAN BERBASIS WEB DENGAN PHP DAN MYSQL

10.12928/telkomnika.v6i2.557
Kartika; Universitas Ahmad Dahlan Firdausy , Samadri; Universitas Ahmad Dahlan Samadri , Anton Yudhana; Universitas Ahmad Dahlan Yudhana
Library are usually used by visitors as media to search a reference and obtain information. Problems at this time is that not many libraries have shaped the web information system for online services. This research aims to analyze and design web-based library information system and testing of the performance of library information systems. Results of research. Results of research shows that the library information system is web-based software built with PHP and MySQL, can work in the Internet network, with the ability to receive data on the WEB library visits, serving registration members get access to a wider, providing services to the availability of information needs click in the form of books, ordering and serving the order book from the members, to serve and return of rental transactions directly.
Volume: 6
Issue: 2
Page: 109-114
Publish at: 2008-08-01

SWIMBLADDER ON FISH TARGET STRENGTH

10.12928/telkomnika.v6i2.561
Sunardi; Universiti Teknologi Malaysia, Universitas Ahmad Dahlan Sunardi , Anton; Universiti Teknologi Malaysia, Universitas Ahmad Dahlan Yudhana , Jafri; Universiti Teknologi Malaysia Din , Raja Bidin Raja; Marine Fishery Resources Development Hassan
This paper discusses of Target Strength (TS) for the Selar boops (Oxeye scad) and Megalaspis cordyla (Torpedo scad), the most commercially fish in Malaysia. TS can be determined from in situ measurements and calculation using acoustic fish model. TS value, depth, and position (x-y-z) of fish targeted can be viewed from echogram using FQ-80 Analyzer by in situ measurement. X-ray imaged can be deployed to develop the acoustic fish model. The percentage of length and upper surface area for swimbladder to body fish of Selar boops more than Megalaspis cordyla can be measured after X-ray process. The percentage of width and volume of swimbladders to its each body are no significantly difference for both fish. These data of swimbladder physic are supports the result from in situ measurement which TS of Megalaspis cordyla have more than Selar boops.
Volume: 6
Issue: 2
Page: 139-144
Publish at: 2008-08-01

PERANCANGAN PURWA RUPA MODULASI LEBAR PULSA BERBASIS TIMER 555 DAN IRF 40

10.12928/telkomnika.v6i2.556
Wahyu Sapto; Universitas Ahmad Dahlan Aji
In many applications such of DC motor speed regulation commonly needed DC to DC voltage conversion. The method that frequently use for DC to DC conversion is using chopper circuit.  In chopper circuit a DC voltage source being chopped at constant frequency but with variable duty cycle (in this case it’s called as Pulse Width Modulation, PWM).  In this research a circuit chopper has been design successfully. The circuit uses 555 timer IC as PWM pulse shaper and IRF 40 power Mosfet as switch device. This circuit prototype successfully tested to drive a 12 watt DC motor at 1200 rpm with voltage at 12 V.
Volume: 6
Issue: 2
Page: 101-108
Publish at: 2008-08-01
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