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Perbandingan Algoritma Golub Kahan danQR Simetri untuk Dekomposisi Nilai Singular Adzkiya, Dieky; Apriliani, Erna; Sanjaya, Bandung Arry
Limits: Journal of Mathematics and Its Applications Vol 3, No 1 (2006)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (186.841 KB) | DOI: 10.12962/j1829605X.v3i1.1393

Abstract

Estimasi variabel maupun parameter pada sistem berskala besar, khusus- nya dengan Filter Kalman dibutuhkan waktu komputasi yang lama. Dengan melakukan reduksi rank matriks kovariansi, waktu komputasi dapat diper- cepat. Reduksi rank dapat dilakukan dengan Dekomposisi nilai singular (SVD), reduksi rank ini tidak mengurangi tingkat akurasi hasil estimasi.Pada paper ini dibahas perbandingan dua algoritma untuk dekomposisi nilai singular, yaitu Golub Kahan dan QR Simetri. Dilakukan uji empiris pada berbagai macam matriks untuk membandingkan waktu kerja kedua algoritma tersebut. Dari hasil simulasi diperoleh bahwa algoritma QR Simetri memerlukan waktu komputasi yang lebih cepat dibandingkan dengan algoritma Golub Kahan.
The Reduced Rank of Ensemble Kalman Filter to Estimate the Temperature of Non Isothermal Continue Stirred Tank Reactor Apriliani, Erna; Adzkiya, Dieky; Baihaqi, Arief
Jurnal Teknik Industri Vol 13, No 2 (2011): DECEMBER 2011
Publisher : Institute of Research and Community Outreach - Petra Christian University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (296.561 KB) | DOI: 10.9744/jti.13.2.107-112

Abstract

Kalman filter is an algorithm to estimate the state variable of dynamical stochastic system. The square root ensemble Kalman filter is an modification of Kalman filter. The square root ensemble Kalman filter is proposed to keep the computational stability and reduce the computational time. In this paper we study the efficiency of the reduced rank ensemble Kalman filter. We apply this algorithm to the non isothermal continue stirred tank reactor problem. We decompose the covariance of the ensemble estimation by using the singular value decomposition (the SVD), and then we reduced the rank of the diagonal matrix of those singular values. We make a simulation by using Matlab program. We took some the number of ensemble such as 100, 200 and 500. We compared the computational time and the accuracy between the square root ensemble Kalman filter and the ensemble Kalman filter. The reduced rank ensemble Kalman filter can’t be applied in this problem because the dimension of state variable is too less.
Safety Verification of SEITR Epidemic Model on Recombination HIV and Hepatitis B Virus using Taylor Model Asmudik, Asmudik; Adzkiya, Dieky; Mardlijah, Mardlijah; Hariyanto, Hariyanto
(IJCSAM) International Journal of Computing Science and Applied Mathematics Vol 7, No 1 (2021)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j24775401.v7i1.7691

Abstract

Human Immunodeficiency Virus (HIV) is an AIDS (Acquired Immuno Deficiency Syndrome) virus that attacks the immune system for which there is no cure. When the immune system has decreased, it is prone to diseases such as Hepatitis B disease. To reduce the error value of the number of subpopulations, we use an interval approximation. One of the simulation calculations that the number of variables initially intervals is Taylor model. Taylor's model can be used to verify that the number of people infected with HIV and Hepatitis B will not exceed the specified number of unsafe sets. To calculate the set of states that are reached by the system over a certain period of time, given the initial conditions and parameters. The initial condition is divided into three scenarios, an affordable set of states, safety verification can be done. As a result of the safety verification of the three scenarios provided there is no set of states that are not safe, so the results of all three scenarios are safe.
Sliding mode control design for autonomous surface vehicle motion under the influence of environmental factor Hendro Nurhadi; Erna Apriliani; Teguh Herlambang; Dieky Adzkiya
International Journal of Electrical and Computer Engineering (IJECE) Vol 10, No 5: October 2020
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (341.862 KB) | DOI: 10.11591/ijece.v10i5.pp4789-4797

Abstract

Autonomous Surface Vehicle (ASV) is a vehicle that is operated in the water surface without any person in the vehicle. Since there is no person in the ASV, a motion controller is essentially needed. The control system is used to make sure that the water vehicle is moving at the desired speed. In this paper, we use a Touristant ASV with the following specifications: the length is 4 meters, the diameter is 1.625 meters, and the height is 1.027 meters. The main contribution of this paper is applying the Sliding Mode Control system to the Touristant ASV model under the influence of environmental factors. The environmental factors considered in this work are wind speed and wave height. The Touristant ASV model is nonlinear and uses three degree of freedom (DOF), namely surge, sway and yaw. The simulation results show that the performance of the closed-loop system by using the SMC method depends on the environmental factors. If environmental factors are higher, then the resulting error is also higher. The average error difference between those resulted from the simulation without environmental factors and those with the influence of environmental factors is 0.05% for surge, sway and yaw motions.
Estimation of closed hotels and restaurants in Jakarta as impact of corona virus disease spread using adaptive neuro fuzzy inference system Mohamad Yusak Anshori; Teay Shawyun; Dennis V. Madrigal; Dinita Rahmalia; Fajar Annas Susanto; Teguh Herlambang; Dieky Adzkiya
IAES International Journal of Artificial Intelligence (IJ-AI) Vol 11, No 2: June 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijai.v11.i2.pp462-472

Abstract

Corona virus disease (COVID-19) have become a world health problem because they have attacked many people worldwide. Because this virus has spread massively in almost all countries, including Indonesia, the Indonesian government made some policies and rules to close down the hotels and restaurants to avoid the spread of COVID-19. Because of that, estimation of the number of closed down restaurants and hotels in Jakarta is vital for avoiding COVID-19 spreads further to other people, either domestic or foreign. In this paper, the adaptive neuro-fuzzy inference system (ANFIS) is chosen as the estimation method. In estimating the number of closed restaurants and hotels using ANFIS, supporting variables such as the amount of casualties in Jakarta, the amount of casualties in Indonesia, and the amount of casualties in the world is required. As a result, ANFIS can estimate the amount of closed down restaurants and hotels approaching the target. The simulations are organized by partitioning the dataset into two parts: data of (80%) and data of testing (20%). According to ANFIS simulations, ANFIS can estimate the number of closed down restaurants and hotels in training data with optimal RMSE equals 0.5324 and testing data with optimal RMSE equals 5.3198.
Business Process Improvement of Production Systems Using Coloured Petri Nets Imam Mukhlash; Widya Nilam Rumana; Dieky Adzkiya; Riyanarto Sarno
Bulletin of Electrical Engineering and Informatics Vol 7, No 1: March 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (430.09 KB) | DOI: 10.11591/eei.v7i1.845

Abstract

The quality of information systems affects the company's business performance. Therefore, it is necessary to analyze business processes to determine any discrepancies between the planned business processes and the actual ones. Based on the results of this analysis, the business process can be improved. The fundamental factor of manufacturing companies is production process. In reality, there are many discrepancies between the actual business processes with the pre-planned, so that there should be analyzed. The analysis can be performed by modeling the business process using Coloured Petri Nets (CPN). In this study, the objectives are to determine the level of conformance checking of business processes, reachability graph and the bottleneck analysis. The results of the analysis are used to construct a recommended model. Based on the analysis of the case study, e.g. a steel industry in Indonesia, the recommended model has a better value than initial model.
Business Process Improvement of Production Systems Using Coloured Petri Nets Imam Mukhlash; Widya Nilam Rumana; Dieky Adzkiya; Riyanarto Sarno
Bulletin of Electrical Engineering and Informatics Vol 7, No 1: March 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (430.09 KB) | DOI: 10.11591/eei.v7i1.845

Abstract

The quality of information systems affects the company's business performance. Therefore, it is necessary to analyze business processes to determine any discrepancies between the planned business processes and the actual ones. Based on the results of this analysis, the business process can be improved. The fundamental factor of manufacturing companies is production process. In reality, there are many discrepancies between the actual business processes with the pre-planned, so that there should be analyzed. The analysis can be performed by modeling the business process using Coloured Petri Nets (CPN). In this study, the objectives are to determine the level of conformance checking of business processes, reachability graph and the bottleneck analysis. The results of the analysis are used to construct a recommended model. Based on the analysis of the case study, e.g. a steel industry in Indonesia, the recommended model has a better value than initial model.
Magnetohidrodinamik Tak Tunak pada Konveksi Campuran yang Mengalir Melalui Bola Teriris Dalam Fluida Kental Di Bawah Pengaruh Medan Magnet Mochamad Satria Dharma Utama; Basuki Widodo; Dieky Adzkiya
Jurnal Sains dan Seni ITS Vol 7, No 1 (2018)
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat (LPPM), ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (932.637 KB) | DOI: 10.12962/j23373520.v7i1.28856

Abstract

Magnetohidrodinamik (MHD) adalah studi mengenai dinamika fluida konduksi listrik akibat medan magnet. Pada penelitian ini diamati permasalahan tentang aliran fluida kental yang mengaliri bola teriris bermagnet dengan alirannya dipengaruhi konveksi campuran dengan berfokus pada kondisi tak tunak. Aliran fluida kental yang melewati bola teriris akan membentuk lapisan batas. Berdasarkan fenomena pada lapisan batas tersebut dibentuk Persamaan Pembangun dari model matematika, Persamaan Pembangun berdimensi ditransformasikan ke dalam bentuk non-dimensional selanjutnya ditransformasikan ke dalam bentuk Persamaan Similaritas. Kemudian, Persamaan Similiritas tersebut diselesaikan secara numerik dengan metode Keller-Box. Setelah itu, dikaji tentang perbandingan parameter yang digunakan yaitu parameter magnetik, parameter konveksi, dan besar sudut irisan bola terhadap kurva kecepatan dan temperatur dengan cara mengembangkan model matematika dari permasalahan di atas dan menyelesaikan secara numerik menggunakan metode Keller-Box. Hasil dari penelitian ini, model matematika yang didapatkan melalui persamaan-persamaan sebelumnya, jika semakin besar parameter magnetik, parameter konveksi dan sudut irisan, maka semakin meningkat pula kecepatan aliran fluida. Sehingga variasi parameter tersebut berbanding lurus dengan kecepatan fluida. Selain itu, jika semakin besar parameter magnetik, parameter konveksi dan sudut irisan, maka semakin berkurang pula temperatur fluida. Sehingga parameter tersebut berbanding terbalik dengan temperatur fluida. Namun pada simulasi temperatur Bilangan Prandtl berlaku sebaliknya. Bilangan Prandtl berbanding lurus dengan temperatur fluida dan berbanding terbalik terhadap kecepatan fluida. Hasil dari setiap simulasi menunjukkan bahwa setiap kurva dari setiap simulasi parameter akan berubah secara signifikan pada setiap perubahan jarak titik penelitan atau jarak lapisan batas.
Business Process Improvement of Production Systems Using Coloured Petri Nets Imam Mukhlash; Widya Nilam Rumana; Dieky Adzkiya; Riyanarto Sarno
Bulletin of Electrical Engineering and Informatics Vol 7, No 1: March 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (430.09 KB) | DOI: 10.11591/eei.v7i1.845

Abstract

The quality of information systems affects the company's business performance. Therefore, it is necessary to analyze business processes to determine any discrepancies between the planned business processes and the actual ones. Based on the results of this analysis, the business process can be improved. The fundamental factor of manufacturing companies is production process. In reality, there are many discrepancies between the actual business processes with the pre-planned, so that there should be analyzed. The analysis can be performed by modeling the business process using Coloured Petri Nets (CPN). In this study, the objectives are to determine the level of conformance checking of business processes, reachability graph and the bottleneck analysis. The results of the analysis are used to construct a recommended model. Based on the analysis of the case study, e.g. a steel industry in Indonesia, the recommended model has a better value than initial model.
Pergerakan Aliran MHD Ag-AIR Melewati Bola Pejal Yolanda Norasia; Basuki Widodo; Dieky Adzkiya
Limits: Journal of Mathematics and Its Applications Vol 18, No 1 (2021)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/limits.v18i1.7888

Abstract

Fluida merupakan zat yang dapat mengalir dan mengalami perubahan secara kontinu akibat adanya tegangan geser. Analisis pengukuran dari ketahanan fluida terhadap tegangan geser menggunakan viskositas. Berdasarkan viskositas, fluida dibagi menjadi dua yaitu fluida newtonian dan fluida non-newtonian.   Fluida non-newtonian terdiri atas fluida viskos, fluida mikropolar dan fluida nano. Salah satu contoh fluida nano adalah Ag-Air. Fluida tersebut tersusun dari fluida dasar air dan partikel nano Ag yang memiliki daya hantar dan tingkat konduktivitas yang tinggi. Adanya pengaruh medan magnet pada Fluida nano Ag-Air, maka menjadi fluida tersebut dapat menghantarkan arus listrik (memiliki sifat magnetohidrodinamik/MHD).  Merujuk pada hasil riset sebelumnya bahwa parameter magnetik dan konveksi dapat mempengaruhi profil kecepatan dan temperatur pada fluida. Pada penelitian ini dibahas mengenai model matematika dan penyelesaian numeriknya dari permasalahan pergerakan aliran MHD Ag-Air yang melewati bola pejal dengan pengaruh parameter magnetik dan konveksi. Diperoleh hasil bahwa variasi magnetik yang meningkat mengakibatkan pergerakan Ag-Air melambat dan temperatur Ag-Air meningkat. Dengan meningkatkan parameter konveksi diperoleh pergerakan Ag-Air lebih cepat dan temperatur Ag-Air mengalami penurunan.