Claim Missing Document
Check
Articles

Found 25 Documents
Search

Dissipative Controller Design for Networked Control Systems via the Markovian Jump System Approach Najmurrokhman, Asep; Riyanto T., Bambang; Syaichu-Rohman, Arief; Hendrawan, H.
Journal of Engineering and Technological Sciences Vol 45, No 1 (2013)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (235.954 KB) | DOI: 10.5614/j.eng.technol.sci.2013.45.1.3

Abstract

This paper describes a dissipative controller design for networked control systems modeled by the Markovian jump system. Dissipativity refers to the existence of a supply rate dealing with the system such that the closed-loop system has a dissipative property. The main result of this paper is a solvability condition in terms of linear matrix inequalities for achieving dissipativity of a dynamic output feedback problem in networked control systems via the Markovian jump system approach. A numerical example is given to show the efficacy of the proposed design.
Rancang Bangun Antena Log Periodic Dipole Array untuk Aplikasi Energy Harvesting Sinyal Seluler Setiawan, Antrisha Daneraici; Ramdani, Dani; Charisma, Atik; Najmurrokhman, Asep
Jurnal Teknik: Media Pengembangan Ilmu dan Aplikasi Teknik Vol 17 No 2 (2018): Jurnal Teknik - Media Pengembangan Ilmu dan Aplikasi Teknik
Publisher : Fakultas Teknik - Universitas Jenderal Achmad Yani

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (590.825 KB) | DOI: 10.26874/jt.vol17no2.81

Abstract

Energy harvesting adalah proses mengambil energi dari alam untuk dimanfaatkan sebagai sumber daya alternatif. Dalam dunia telekomunikasi, sebagian besar sinyal seluler yang dipancarkan oleh base transreceiver station (BTS) tidak akan diterima oleh pengguna telepon seluler. Hanya sebagian kecil saja yang dimanfaatkan untuk saling berkomunikasi antara pengguna dan BTS. Sinyal ini dapat dipanen dengan menggunakan antena dengan frekuensi kerja yang sesuai. Sinyal yang akan dipanen adalah sinyal pada frekuensi sekitar 1,8 GHz. Antena log periodic dipole array (LPDA) memiliki gain yang tinggi sehingga dapat memanen sinyal seluler dengan baik jika diarahkan ke sumber sinyal atau BTS. Perancangan antena LPDA dilakukan dengan melakukan simulasi pada perangkat lunak CST. Ukuran antena LPDA dihitung berdasarkan persamaan yang telah ada dan dilakukan optimasi untuk mendapatkan spesifikasi yang diinginkan. Antena LPDA berbahan dasar alumunium. Hasil simulasi memiliki rentang frekuensi kerja pada 1,7764 – 1,9044 GHz dengan bandwidth antena sebesar 128 MHz. Nilai S11 minimum terdapat pada frekuensi 1,8308 GHz sebesar -56,6837 dB. Sedangkan antena fabrikasi memiliki rentang frekuensi 1,738 – 1,846 GHz dengan bandwidth 108 MHz. Nilai minimum S11 sebesar -35,7 dB berada pada frekuensi 1,792 GHz.
Karakterisasi Konveks Melalui Pertidaksamaan Matriks Non Linier pada Analisis Stabilitas Kendali H∞ untuk Sistem Non Linier Najmurrokhman, Asep
Jurnal Teknik: Media Pengembangan Ilmu dan Aplikasi Teknik Vol 1 No 1 (2002): Jurnal Teknik - Media Pengembangan Ilmu dan Aplikasi Teknik
Publisher : Fakultas Teknik - Universitas Jenderal Achmad Yani

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26874/jt.vol1no1.196

Abstract

In this paper, stability analysis of nonlinear systems is considered. Existence of Lyapunov function as stability guarantee for a class of nonlinear systems is characterized in terms of nonlinear matrix inequalities which result in convex feasibility problems. A numerical example will be shown for clarity this method. The issue of solutions to these nonlinear matrix inequalities is proposed.
Analisis Sistem Kendali Kokoh pada Sistem Non Linier dengan Pendekatan Pertidaksamaan Matriks Non Linier Najmurrokhman, Asep
Jurnal Teknik: Media Pengembangan Ilmu dan Aplikasi Teknik Vol 1 No 2 (2002): Jurnal Teknik - Media Pengembangan Ilmu dan Aplikasi Teknik
Publisher : Fakultas Teknik - Universitas Jenderal Achmad Yani

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26874/jt.vol1no2.204

Abstract

This paper proposes about robust control systems analysis for a class of nonlinear systems using nonlinear matrix inequalities approach. Robustness corresponds with appropriately disturbance suppression. Controller that renders robustness property of the system is developed with solving solvability condition in advance. Such condition is described by three nonlinear matrix inequalities. Computational aspect is considered to solve these matrix inequalities.
Perancangan Sistem Robot Cerdas Berbasis Logika Fuzzy Asep Najmurrokhman
Jurnal Teknik: Media Pengembangan Ilmu dan Aplikasi Teknik Vol 5 No 2 (2006): Jurnal Teknik - Media Pengembangan Ilmu dan Aplikasi Teknik
Publisher : Fakultas Teknik - Universitas Jenderal Achmad Yani

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26874/jt.vol5no2.256

Abstract

Makalah ini memaparkan tentang klasifikasi robot dan beberapa prototipe yang pernah dirancang oleh penulis. Robot-robot tersebut meliputi manipulator, mobile robot, dan robot heksapoda. Sementara itu, seiring dengan kemajuan dalam bidang kendali cerdas (intelligent control), dibahas pula skema pengendalian gerak robot secara cerdas berbasis logika fuzzy. Penggunaan logika fuzzy dalam implementasi pengendalian gerak robot dipicu oleh kompleksitas yang ada dalam sistem robot, sehingga implementasi pengendali linier seperti PID tidak akan dapat menangani dinamika robot tersebut, di lain pihak, realisasi dengan pengendali non linier akan sangat rumit atau paling tidak memberi beban komputasi pada pengendalinya. Sebagai studi kasus, diuraikan perancangan dan simulasi sistem fuzzy dalam mobile robot. Hasil simulasi memperlihatkan bahwa pendekatan logika fuzzy dalam implementasi mobile robot dapat mengakomodasi sisi kecerdasan dalam pengambilan keputusan gerak dari mobile robot tersebut berdasarkan basis aturan yang diberikan padanya.
Dissipative Approach in Analysis and Synthesis of Control System via Linear Matrix Inequalities Asep Najmurrokhman
Jurnal Teknik: Media Pengembangan Ilmu dan Aplikasi Teknik Vol 7 No 2 (2008): Jurnal Teknik - Media Pengembangan Ilmu dan Aplikasi Teknik
Publisher : Fakultas Teknik - Universitas Jenderal Achmad Yani

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26874/jt.vol7no2.282

Abstract

This paper discusses about application of dissipative concept in dynamical systems for analysis and synthesis of control systems via linear matrix inegualities (LMIs). Motivated by dissipativity concept in mechanical and electrical circuit system, one could employ this concept to check stability and to design a controller of the underlying system. We derive the solvability condition of dissipativity for an output feedback LTI continuous system via LMIs. An algorithm to design such controller that satisfy the dissipativity of the system is also considered.
Perancangan Electronic Load Controller Berbasis Mikrokontroler sebagai Stabilizer Tegangan dan Frekuensi Asep Najmurrokhman; Kurnia A
Jurnal Teknik: Media Pengembangan Ilmu dan Aplikasi Teknik Vol 9 No 2 (2010): Jurnal Teknik - Media Pengembangan Ilmu dan Aplikasi Teknik
Publisher : Fakultas Teknik - Universitas Jenderal Achmad Yani

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26874/jt.vol9no2.324

Abstract

Kestabilan frekuensi dan tegangan sangat diperlukan dalam kelangsungan pelayanan tenaga listrik dari suatu pembangkit listrik. Pemakaian beban konsumen yang tidak menentu menyebabkan frekuensi dan tegangan yang berubah-ubah. Frekuensi dan tegangan yang tidak stabil merusak peralatan (beban) karena beban tidak bisa bekerja secara optimal. Dalam makalah ini diuraikan tentang perancangan electronic load controller (ELC) berbasis mikrokontroler sebagai stabilizer tegangan dan frekuensi. Alat ini dapat mencegah kerusakan akibat frekuensi dan tegangan keluaran dari sistem distribusi energi listrik yang tidak stabil. Pengontrolan beban secara elektronik menggunakan pengondisi sinyal frekuensi dan tegangan yang akan mendeteksi frekuensi dan tegangan sebelum masuk ke beban, yang kemudian akan dibaca oleh mikrokontroler. Data akan diproses untuk menentukan kerja dari sistem dan frekuensi, tegangan akan ditampilkan pada LCD. Sistem pengaturan frekuensi dan tegangan melalui pengaturan beban secara elektronik bekerja dengan mengatur daya yang disalurkan ke beban sekunder setiap terjadi perubahan frekuensi dan tegangan akibat perubahan beban pada beban utama. Dengan demikian, beban total generator (beban utama dan beban komplemen) cenderung tetap. Hasil pengujian menunjukkan frekuensi dan tegangan yang diatur bersifat stabil saat diberi beban maupun tidak diberi beban.
High Sensitivity Very Low Frequency Receiver for Earthquake Data Acquisition Achmad Munir; Kusmadi Kusmadi; Kusnandar Kusnandar; Asep Najmurrokhman; Chairunnisa Chairunnisa; Sunubroto Sunubroto
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 15, No 1: March 2017
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v15i1.3484

Abstract

A high sensitivity very low frequency (VLF) receiver is developed based on AD744 monolithic operational amplifier (Op-Amp) for earthquake data acquisition. In research related natural phenomena such as atmospheric noise, lightning and earthquake, a VLF receiver particularly with high sensitivity is utterly required due to the low power of VLF wave signals received by the antenna. The developed receiver is intended to have high sensitivity reception for the signals in frequency range of 10-30 kHz allocated for earthquake observation. The VLF receiver which is portably designed is also equipped with an output port connectable to the soundcard of personal computer for further data acquisition. After obtaining the optimum design, the hardware realization is implemented on a printed circuit board (PCB) for experimental characterization. It shows that the sensitivity of realized VLF receiver is almost linear in the predefined frequency range for the input signals lower than -12dBm and to be quadratic for the higher level input signals.
Dissipative Controller Design for Networked Control Systems via the Markovian Jump System Approach Asep Najmurrokhman; Bambang Riyanto T.; Arief Syaichu-Rohman; H. Hendrawan
Journal of Engineering and Technological Sciences Vol. 45 No. 1 (2013)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2013.45.1.3

Abstract

This paper describes a dissipative controller design for networked control systems modeled by the Markovian jump system. Dissipativity refers to the existence of a supply rate dealing with the system such that the closed-loop system has a dissipative property. The main result of this paper is a solvability condition in terms of linear matrix inequalities for achieving dissipativity of a dynamic output feedback problem in networked control systems via the Markovian jump system approach. A numerical example is given to show the efficacy of the proposed design.
Emotion brain-computer interface using wavelet and recurrent neural networks Esmeralda Contessa Djamal; Hamid Fadhilah; Asep Najmurrokhman; Arlisa Wulandari; Faiza Renaldi
International Journal of Advances in Intelligent Informatics Vol 6, No 1 (2020): March 2020
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26555/ijain.v6i1.432

Abstract

Brain-Computer Interface (BCI) has an intermediate tool that is usually obtained from EEG signal information. This paper proposed the BCI to control a robot simulator based on three emotions for five seconds by extracting a wavelet function in advance with Recurrent Neural Networks (RNN). Emotion is amongst variables of the brain that can be used to move external devices. BCI's success depends on the ability to recognize one person’s emotions by extracting their EEG signals. One method to appropriately recognize EEG signals as a moving signal is wavelet transformation. Wavelet extracted EEG signal into theta, alpha, and beta wave, and consider them as the input of the RNN technique. Connectivity between sequences is accomplished with Long Short-Term Memory (LSTM). The study also compared frequency extraction methods using Fast Fourier Transform (FFT). The results showed that by extracting EEG signals using Wavelet transformations, we could achieve a confident accuracy of 100% for the training data and 70.54% of new data. While the same RNN configuration without pre-processing provided 39% accuracy, even adding FFT would only increase it to 52%. Furthermore, by using features of the frequency filter, we can increase its accuracy from 70.54% to 79.3%. These results showed the importance of selecting features because of RNNs concern to sequenced its inputs. The use of emotional variables is still relevant for instructions on BCI-based external devices, which provide an average computing time of merely 0.235 seconds.