Article Per Year (5 Year)
p-Index From 2021 - 2026
1.2
P-Index
This Author published in this journals
All Journal TELKOMNIKA (Telecommunication Computing Electronics and Control) Indonesian Journal of Electrical Engineering and Computer Science INOVTEK Polbeng - Seri Informatika
Okfalisa Okfalisa
Universitas Islam Negeri Sultan Syarif Kasim
Computer Science & IT

Published : 6 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 6 Documents
Search

 1 
Transmission spectra of single ring coupled-waveguide resonator configuration by finite difference time domain method Haryana bin Mohd Hairi; Saktioto Saktioto; Romi Fadli Syahputra; Okfalisa Okfalisa; Sofia Anita
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 18, No 5: October 2020
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v18i5.12621

Abstract

Development of optical waveguide resonators have greatly expanded and continues to grow since they have kinds potential applications such as wavelength filtering, switching, coupling and multiplexing. One of resonators, coupled waveguides, ring resonators are designed and operated using various coupling configurations. Ring resonators can be particularly used as wavelength filter if the wavelength can fit a whole multiple time in the circumference of the ring. This article proposes to investigate the transmission spectra from the power source and amplify it in linearized ring resonator configurations and varies the input amplitude on five different wavelengths. With finite difference time domain method, the geometry and power source are simulated to obtain the better result and configuration. The results show the intensity phenomena of filtering in optical circuit.
Apodization sensor performance for TOPAS fiber Bragg grating Toto Saktioto; Khaikal Ramadhan; Yan Soerbakti; Romi Fadli Syahputra; Dedi Irawan; Okfalisa Okfalisa
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 19, No 6: December 2021
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v19i6.21669

Abstract

Optical sensors have more capabilities than electronic sensors, and therefore provide extraordinary developments, including high sensitivity, non-susceptibility to electromagnetic wave disturbances, small size, and multiplexing. Furthermore, fiber Bragg grating (FBG) is an optical sensor with a periodically changing grating refractive index, susceptible to strain and temperature changes. As a sensor, FBG’s performance required to optimize and improve the numerical apodization function and affect the effective refractive index is considered. The grating fiber’s apodization function can narrow the full width half maximum (FWHM) and reduce the optical signal’s side lobes. In all the apodization functions operated by FBG, Blackman has the highest sensitivity of 15.37143 pm/°C, followed by Hamming and Gaussian, with 13.71429 pm/°C and 13.70857 pm/°C, respectively, and Uniform grating fiber with the lowest sensitivity of 12.40571 pm/°C. Hamming, Uniform, and Blackman discovered the sensitivity for a strain to be 1.17, 1.16, and 1.167 pm/microstrain, respectively. The results obtained indicated that apodization could increase FBG’s sensitivity to temperature and strain sensors. For instance, in terms of other parameters, FWHM width, Hamming had the narrowest value of 0.6 nm, followed by Blackman with 0.612 nm, while Uniform had the widest FWHM of 1.9546 nm.
Measuring information security policy compliance: content validity of questionnaire Angraini Angraini; Rose Alinda Alias; Okfalisa Okfalisa
Indonesian Journal of Electrical Engineering and Computer Science Vol 22, No 1: April 2021
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v22.i1.pp469-475

Abstract

Instruments used to measure compliance with information security policies have been developed by many researchers before, but only a few have conducted validity tests per item, especially for variables selected based on qualitative research. This study aims to validate the questionnaire will be used to measure user compliance with policies of information security. This study began by designing a questionnaire and conducting content validation using content ratio validation (CVR) and content index validation (CVI). As many as eight experts from the university assessed the items given. The results of 72 items submitted a questionnaire, as many as 22 items eliminated, and only 50 items that have CVR and CVI values above 0.75. Also, Kappa statistical calculations show that items have excellent reliability among assessors at the item level. This study revealed that this instrument had obtained an appropriate level of validity to measure compliance with information security policies. 
Airflow vibration of diaphragmatic breathing: model and demonstration using optical biosensor Toto Saktioto; Defrianto Defrianto; Nurfi Hikma; Yan Soerbakti; Syamsudhuha Syamsudhuha; Dedi Irawan; Okfalisa Okfalisa; Bambang Widiyatmoko; Dwi Hanto
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 21, No 3: June 2023
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v21i3.23613

Abstract

Optical fiber is increasingly popular and appreciated as a modern sensor technology in various sectors, one of which is for medical functions. This study was conducted to detect human diaphragmatic breathing flow using theoretical and experimental approaches. Initially, the lung model was formed using the finite element method and the Navier-Stokes equation by applying the principles of momentum and continuity. Furthermore, fiber Bragg grating (FBG) and single mode fiber (SMF) were experimentally designed with sinusoidal patterned macro-scale bending as a stretch sensor in a breathing belt applied to the diaphragm. The simulation model shows the airflow velocity increases up to 4 m/s when it flows into smaller branches. While the experimental results show that the largest power loss occurs at a buffer diameter of 0.8 cm. The power loss detected in SMF is a maximum of -0.18 dBm during inhalation and a minimum of -0.28 dBm during expiration. However, FBG bending is superior with high sensitivity.
Application of ARIMA and ARIMAX Methods to Predict the Number of Visitors to Hotel XYZ Pekanbaru Julio Vernando; Fitri Insani; Okfalisa Okfalisa; Fitra Kurnia
Journal of Innovation and Technology Polbeng Series on Informatics (INOVTEK Polbeng - Seri Informatika) Vol. 10 No. 2 (2025): July
Publisher : P3M Politeknik Negeri Bengkalis

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35314/enrfna19

Abstract

Predicting the number of visitors to Hotel XYZ is one of the steps that can be taken by the hotel to find out how many visitors will increase in each upcoming holiday season. The purpose of this study is to forecast the number of visitors to Hotel XYZ from June 2023 to July 2024 using the ARIMA and ARIMAX comparison methods. The research methodology encompasses problem identification, data collection, data processing, and ARIMA and ARIMAX analysis, which involves testing the parameters (p, d, q) selected based on the ACF and PACF using the AIC Model. Based on the test results, ARIMAX (5, 0, 3) has the lowest AIC, which is 3495.2, followed by ARIMAX (3, 0, 5), which has a slightly higher AIC. The results showed that the ARIMAX (5, 0, 3) model is the most accurate model for predicting data (eg the number of hotel guests, room demand, or income), with an RMSE value of 15.80% and a MAPE of 18.90%. Therefore, research that applies the ARIMAX model can provide real benefits in supporting operational efficiency, resource management, and hotel business strategy, ultimately increasing the competitiveness and profitability of the hotel.
Application of ADASYN Technique in Classification of Stroke Disease using Backpropagation Neural Network said rizki zikrillah aulia; okfalisa okfalisa; elin haerani; lola oktavia
Journal of Innovation and Technology Polbeng Series on Informatics (INOVTEK Polbeng - Seri Informatika) Vol. 10 No. 3 (2025): November
Publisher : P3M Politeknik Negeri Bengkalis

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35314/jdhv9s39

Abstract

The high prevalence of stroke in Indonesia and the challenge of imbalanced medical record data are major obstacles to the development of an accurate early detection system. This research aims to build a reliable stroke classification model by applying the ADASYN (Adaptive Synthetic Sampling) oversampling technique to address class imbalance before the data is processed using the Backpropagation Neural Network (BPNN) algorithm. The ADASYN technique is applied with the goal of reducing the bias that arises from the imbalanced data distribution between the majority and minority classes. Testing was conducted through various data splitting scenarios (70:30, 80:20, 90:10) and hyperparameter variations to find the optimal configuration. The best results were obtained with the 90:10 data split scheme, using an architecture of 29 neurons and a learning rate of 0.01, which successfully achieved peak performance with an accuracy of 90.46% and an F1-score of 91.03%. This study demonstrates that the combination of ADASYN and BPNN is a highly effective approach for producing a stroke prediction model that is not only accurate but also sensitive to the minority class, thus having great potential as an early detection support tool in the healthcare sector.
Co-Authors Angraini Angraini Anita, Sofia Bambang Widiyatmoko Dedi Irawan Defrianto Defrianto Dwi Hanto Elin Haerani Fitra Kurnia Fitri Insani Haryana bin Mohd Hairi Julio Vernando Khaikal Ramadhan Lola Oktavia Nurfi Hikma Romi Fadli Syahputra Rose Alinda Alias said rizki zikrillah aulia Saktioto Saktioto Syamsudhuha Syamsudhuha Yan Soerbakti