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OPTIMASI KECEPATAN SUDUT KELUARAN KOPELING UNIVERSAL PADA POROS SERI Fajar, Muhammad
Jurnal Teknik Mesin Vol 9, No 1 (2007): APRIL 2007
Publisher : Institute of Research and Community Outreach - Petra Christian University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (207.267 KB) | DOI: 10.9744/jtm.9.1.pp. 40-46

Abstract

The shafts in the steering linkage are connected by universal joints. These joints has characteristic producing fluctuation in the output angular velocity. So, this can cause a problem for steering linkage as the fluctuation of the output steering shaft. Furthermore, it will affect the ability to control the moving of the vehicle. Ideally, the input and the output angular velocity of the steering wheel should be equal so that the controlling of the vehicle motion by the driver could be easly or fully handling. In this research the output angular velocity of a series shafts connected by universal joint or also popular called Hooke's joint is optimised. It is usually applied in huge vehicles or truck steering linkage connection system. The optimisation will be done by developing Shaft Series Optimisation (SSO) package by utilising MATLAB Optimisation Toolbox. From the result of calculations using the developed software package it can be concluded that the output velocity of the series shafts approximates the input velocity at the operating angle less than 25º and at the phase angle of 90º. Abstract in Bahasa Indonesia : Pada umumnya mekanisme batang penghubung sistem kemudi menggunakan tipe sambungan kopeling universal yang memiliki karakteristik khas yaitu menghasilkan kecepatan sudut keluaran yang fluktuatif. Sebagai akibatnya, hal ini akan mempengaruhi tingkat kemampuan pengontrolan gerakan kendaraan. Kondisi ideal pengontrolan dapat dicapai jika kecepatan sudut masukan dari roda kemudi sama dengan kecepatan sudut poros keluaran yang terhubung ke kotak kemudi servo (power steering). Pada kondisi ini, pengontrolan gerakan kendaraan oleh pengemudi menjadi lebih mudah (fully handle). Oleh sebab itu, dalam penelitian ini dilakukan optimasi kecepatan sudut keluaran sebuah poros seri yang terhubung dengan kopeling universal atau juga dikenal dengan kopeling Hook. Sistem seperti ini umumnya diterapkan pada sistem penghubung kemudi kendaraan-kendaran besar atau truk. Optimasi dilakukan melalui pembuatan paket perangkat lunak Shaft Series Optimisation (SSO) berbasis Optimisation Toolbox dari MATLAB. Berdasarkan hasil perhitungan melalui paket SSO diperoleh hasil bahwa untuk tiga buah sambungan dengan empat buah poros seri ternyata kecepatan sudut masukan dan keluaran poros seri akan mendekati sama pada sudut operasi lebih kecil daripada 25° dan sudut fasa pada 90°. Kata kunci: Optimasi, kopeling universal, kecepatan sudut, poros seri, kemudi, pemrograman tak linier.
Relasi Intelektual, Modal, dan Negara di Indonesia: Faktor-faktor Yang Mengkondisikan dan Implikasinya Fajar, Muhammad
Jurnal Politik Vol 1, No 1 (2010): Jurnal Studi Politik
Publisher : Department of Political Science Universitas Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2206.452 KB) | DOI: 10.7454/jp.v1i1.101

Abstract

Dalam pengalaman relasi intelektual, modal dan negara pada era Reformasi, terdapat dua faktor yang mempengaruhi bagaimana relasi tersebut terbentuk. Secara struktural, faktor pertama ialah dorongan pencarian legitimasi politik oleh negara dan faktor kedua, pengaruh neo-liberalisme. Dua kasus yang menunjukkan relasi tersebut dapat dilacak pada kasus Kelompok Bakrie-Freedom Institute-negara dan relasi Asian Agri-intelektual kampus. Pada kasus pertama, kelompok intelektual mengafirmasi perilaku kelas borjuis dengan perantara ideology liberalisme. Sementara kasus kedua menunjukkan kelompok intelektual yang mendukung klaim-klaim kebenaran dalam ranah hukum lewat kerja-kerja penelitian.
PERANCANGAN AUTOPILOT LATERAL-DIREKSIONAL PESAWAT NIRAWAK LSU-05 (THE DESIGN OF THE LATERAL-DIRECTIONAL AUTOPILOT FOR THE LSU-05 UNMANNED AERIAL VEHICLE) Fajar, Muhammad; Arifianto, Ony
Jurnal Teknologi Dirgantara Vol. 15 No. 2 Desember 2017
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2017.v0.a2760

Abstract

The autopilot on the aircraft is developed based on the mode of motion of the aircraft i.e. longitudinal and lateral-directional motion. In this paper, an autopilot is designed in lateral-directional mode for LSU-05 aircraft. The autopilot is designed at a range of aircraft operating speeds of 15 m/s, 20 m/s, 25 m/s, and 30 m/s at 1000 m altitude. Designed autopilots are Roll Attitude Hold, Heading Hold and Waypoint Following. Autopilot is designed based on linear model in the form of state-space. The controller used is a Proportional-Integral-Derivative (PID) controller. Simulation results show the value of overshoot / undershoot does not exceed 5% and settling time is less than 30 second if given step command. Abstrak Autopilot pada pesawat dikembangkan berdasarkan pada modus gerak pesawat yaitu modus gerak longitudinal dan lateral-directional. Pada makalah ini, dirancang autopilot pada modus gerak lateral-directional untuk pesawat LSU-05. Autopilot dirancang pada range kecepatan operasi pesawat yaitu 15 m/dtk, 20 m/dtk, 25 m/dtk, dan 30 m/dtk dengan ketinggian 1000 m. Autopilot yang dirancang adalah Roll Attitude Hold, Heading Hold dan Waypoint Following. Autopilot dirancang berdasarkan model linier dalam bentuk state-space. Pengendali yang digunakan adalah pengendali Proportional-Integral-Derivative (PID). Hasil simulasi menunjukan nilai overshoot/undershoot tidak melebihi 5% dan settling time kurang dari 30 detik jika diberikan perintah step.
MEMBANGUN APLIKASI GAME “DUA SATU (21)” BERBASIS ANDROID MENGGUNAKAN METODE DEPTH FIRST SEARCH Fajar, Muhammad; Ningrum, Ika Purwanti; Ramadhan, Rahmat
semanTIK Vol 1, No 2 (2015): semanTIK
Publisher : Informatics Engineering Department of Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (183.291 KB)

Abstract

Kata game berasal dari bahasa inggris yang berarti permainan. Saat ini game berkembang di aplikasi mobile. Salah satu sistem operasi untuk perangkat mobile adalah Android. Perkembangan sistem operasi mobile Android diakibatkan oleh kelebihannya yang bersifat terbuka, sehingga kemudahan dalam menggunakannya menjadi nilai tambah. Hal ini menyebabkan pemakaian mobile Android terus meningkat. Untuk pencarian solusi dalam sebuah game dapat menggunakan metode pencarian, salah satunya adalah algoritma Depth-First Search (DFS). Dalam metode pencarian Depth First Search (DFS), pencarian dilakukan pada satu node dalam setiap level dari yang paling kiri. Jika pada level yang paling dalam solusi belum ditemukan, maka pencarian dilanjutkan pada node sebelah kanan. Pada penelitian ini, algoritma pencarian Depth First Search (DFS) diimplementasikan dalam sebuah game. Game yang diciptakan dalam penelitian ini adalah game Dua Satu (21). Hasil dari penelitian ini menunjukan bahwa algoritma pencarian Depth First Search dapat diterapkan dalam aplikasi game Dua Satu (21), namun tidak lengkap karena dari 144 kombinsi angka yang menjadi masukan, terdapat 30 kombinasi angka yang tidak muncul solusinya. Hal ini merupakan salah satu kekurangan dari algoritma pencarian Depth First Search yang memungkinkan untuk tidak ditemukannya solusi. Selain itu, hasil pengujian aplikasi ini ke beberapa smartphone juga menunjukkan kondisi yang sama, yaitu masih terdapat kombinasi angka yang tidak muncul solusinya, jadi spesifikasi dan merek smartphone tidak mempengaruhi hasil keluaran Kata Kunci : Game, Mobile, Depth First Search (DFS), Android dan Dua Satu (21).
PENGARUH PROFITABILITAS DAN LEVERAGE TERHADAP HARGA SAHAM PADA PERUSAHAAN SUB SEKTOR OTOMOTIF DAN KOMPONEN YANG TERDAFTAR DI BURSA EFEK INDONESIA Fajar, Muhammad; Ibrahim, Mariaty
Jurnal Online Mahasiswa (JOM) Bidang Ilmu Sosial dan Ilmu Politik Vol. 6: Edisi I Januari - Juni 2019
Publisher : Fakultas Ilmu Sosial dan Ilmu Politik Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Penelitisn aims to determine the effect of Profitabolitas and Leverage on Stock Price at automotive sub-companies and Components listed on the Indonesia Stock Exchange. Profitability is used as independent variable (X) that is with indicator Return On Asset (ROA), and Leverage with indicator that is Debt to Equity Ratio (DER). While used as the dependent variable (Y) is Price Earning Price Earning Ratio (PER). This research used secondary data that is financial report of Automotive and Components sub sector that listed in Indonesia Stock Exchange (BEI). Sampling was done by sampling the samples used were 12 Automotive and Component sub sector. The technique used is simple linear regression, multiple linear regression, coefficient of determination test, t test, and f test. Data analysis using linear regression analysis with SPSS 21 software. From result of research indicate that variable of Profitability and Leverage partially (t test) does not have an effect on Stock Price in Automotive sub sector and Component company listed in Indonesia Stock Exchange (BEI). The result of simultaneous research (Test f) shows that there is no influence of Profitability and Leverage variable on Stock Price in Automotive and Component sub sector companies listed in Indonesian Stock Exchange.
The Comparison Effect of Electrical Cigarrete and Conventional Cigarrete Smoke toward White Rat’s (Rattus norvegicus) Lung Histopathology Triantara, Yoan Asri; Almira, Inggit; Kusumo, Sarwan Adi; Fajar, Muhammad; Darmawan, Dicky; Winarni, Dwi
Jurnal Respirologi Indonesia Vol 39, No 2 (2019)
Publisher : Perhimpunan Dokter Paru Indonesia (PDPI)/The Indonesian Society of Respirology (ISR)

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Abstract

Background: The number of cigarettes smoked per day has an average of 12,3% of cigarettes in 2013. The increase of the conventional cigarettes price in 2016 made some conventional smokers switch to electrical cigarettes because more safety than conventional One of the indicators of pulmonary damage is the increase of alveolar macrophage that cause pulmonary structural change triggered by substances in the cigarette. Methods: Thirty two of white rat were divided into four groups (control, conventional cigarette, electrical cigarette with 0 miligram (mg) nicotine, and electrical cigarette with 3 mg nicotine) and were exposed for 35 days (30x2 minutes; in the morning and evening). Results: The group exposed to conventional cigarette smoke has the highest average number of macrophages than the cigarette smoke group with nicotin levels of 0 mg, electric cigarette with 3 mg nicotine and control. Brown Forsythe test continued with Games-Howell post hoc test indicates that there are significant mean difference between each group except between group exposed to electric cigarette smoke with 3 mg nicotine and exposed to conventional cigarette smoke. Based on the indicator assumption of lymphoid infiltration and thickening and fusion of the alveolar, the smoke of conventional cigarette and electric cigarette with 3 mg nicotine caused more histopathological damage to the white rat’s lungs than of conventional cigarette than the smoke of electric cigarette with 0 mg nicotine and those in the control group. Conclusion: The exposure of conventional cigarette smoke caused the highest damage to Rattus norvegicus’ pulmo according to macrophage alveolar and histopathological indicator, but not significantly different with the exposure of electrical cigarette with 3 mg nicotine. The exposure of electrical cigarette with 0 mg nicotine caused minor damage equals to control group based on histopathological indicator. (J Respir Indo 2019; 39(2))
Sistem Proteksi Pelepasan Beban dengan Metode Descending Menggunakan Macro VBA Fajar, Muhammad; Rhomadhona, Herfia; Hafizd, Khairul Anwar
Jurnal Sains dan Informatika Vol 5 No 1 (2019): Jurnal Sains dan Informatika
Publisher : Teknik Informatika, Politeknik Negeri Tanah Laut

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (422.129 KB) | DOI: 10.34128/jsi.v5i1.165

Abstract

The last few months, PT. PLN WKSKT deliberately goes out to prevent the failure of the generator system network. Blackouts occur because there are uneven load uses. The use of the largest load is in the Barikin transmission line scheme towards the Tanjung and Cempaka direction. Both schemes are crucial load conditions when there is a disruption in the transmission line. This can interfere with the transmission of the load on targets that are in the two schemes, cause trips and blackouts. To resolve the issue, PT. PLN WKSKT create a special scheme for the protection system loads on specific targets. Which system can sort the target load from large to small. Descending is a sorting method that can complete the purpose of a protection system. With this method the target load is sorted and then calculated in VBA macros. The target load that has been sorted is then added to the equivalent of the line transfer. Calculations performed on VBA macros aim to obtain load release status based on enable, ready and trip indications. All three indicators used to monitor the load condition real time. So that the protection system is able to avoid interference that can cause black out on the electrical system.
PERBANDINGAN ALGORITMA PERLUASAN JARINGAN TELEKOMUNIKASI DENGAN MOBILE ROBOT DI DAERAH BENCANA MENGGUNAKAN OPEN DYNAMIC ENGINE Ramadhan, Arief; Hafidh, Abdullah; Suryana, M. Eka; Fajar, Muhammad
Jurnal Ilmu Komputer dan Informasi Vol 4, No 2 (2011): Jurnal Ilmu Komputer dan Informasi (Journal of Computer Science and Information)
Publisher : Faculty of Computer Science - Universitas Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1115.833 KB) | DOI: 10.21609/jiki.v4i2.170

Abstract

Putusnya jaringan komunikasi sebagai dampak suatu bencana merupakan permasalahan yang perlu cepat diatasi agar tidak menimbulkan kerugian yang lebih besar. Komunikasi antara lokasi bencana dengan dunia luar menjadi sangat penting dalam menentukan tindakan yang tepat untuk meminimalisasi kerugian akibat bencana. Kajian penggunaan mobile robot otonom untuk menghubungkan menara-menara komunikasi yang terputus dapat menjadi solusi alternatif untuk mengatasi masalah ini. Dalam penelitian ini, penulis mengkaji beberapa algoritma perluasan jaringan dalam bentuk simulasi menggunakan Library Open Dynamic Engine. Library Open Dynamic Engine merupakan library yang telah menggunakan perhitungan fisika secara efisien dan teruji sehingga dapat mendekati keadaan dunia sebenarnya. Simulasi ini bertujuan untuk mendemontrasikan serta membandingkan bahwa algoritma ini dapat dikembangkan untuk menghubungkan menara komunikasi. The disconnection in communication networks as the impact of a disaster is a problem that needs to be addressed quickly in order to avoid greater losses. Communication between the disaster site with the outside world becomes very important in determining the appropriate action to minimize losses due to disasters. Study the use of autonomous mobile robots for connecting communication towers that was disconnected can be alternative solutions to address these issues. In this study, the authors examine some of the network expansion algorithm in the form of a simulation using Open Dynamics Engine library. Library of Open Dynamic Engine is a library that has used physics calculations in an efficient and tested so can approach the state of the real world. This simulation aims to demonstrate and compare that this algorithm can be developed to connect the communication towers.
IMPLEMENTASI SISTEM KLASIFIKASI MOBIL PADA SISTEM PENGATURAN LAMPU LALU LINTAS TERDISTRIBUSI BERBASISKAN JARINGAN SYARAF TIRUAN Ramadhan, Arief; Fajar, Muhammad; Suryana, M. Eka; Zaman, Big
Jurnal Ilmu Komputer dan Informasi Vol 4, No 2 (2011): Jurnal Ilmu Komputer dan Informasi (Journal of Computer Science and Information)
Publisher : Faculty of Computer Science - Universitas Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (800.535 KB) | DOI: 10.21609/jiki.v4i2.165

Abstract

Sistem Pengaturan Lampu Lalu Lintas Terdistribusi adalah sebuah sistem lampu lalu lintas yang ditujukan untuk memenuhi kebutuhan akan kinerja pengaturan lampu lalu lintas yang cerdas dengan pengambilan data secara real-time. Sistem ini dapat melakukan penjadwalan dan pengaturan jaringan banyakpersimpangan secarareal-time yang tidak bisa dilakukan oleh sistem pengaturan lampu lalu lintas konvensional. Penerapan klasifikasi di dalam sistem ini digunakan untuk meningkatkan akurasi dari pengenalan mobil. Proses klasifikasi diimplementasikan menggunakan tiga algoritma Jaringan Syaraf Tiruan, yakni Backpropagation, FLVQ, dan FLVQ-PSO. Berdasarkan hasil ujicoba, dapat ditunjukkan bahwa algoritma Backpropagationmemiliki performa akurasi yang lebih baik dibandingkan dua algoritma JST yang lainnya. Distributed Traffic Light Control System is a traffic light system intended to meet the need for setting the performance of intelligent traffic lights with real-time data capturing. The system can perform scheduling and network settings of multi-junction in real time that can not be done by a conventional traffic light settings system. Application of classification within this system is used to improve the accuracy of the car recognition. Classification process is implemented using three neural network algorithms, namely Backpropagation, FLVQ, and FLVQ-PSO. Based on the test results, it can be shown that the Backpropagation algorithm performs better accuracy than the other two algorithms.
IMPLEMENTATION COLOR FILTERING AND HARRIS CORNER METHOD ON PATTERN RECOGNITION SYSTEM Zarkasi, Ahmad; Sutarno, Sutarno; Ubaya, Huda; Fajar, Muhammad
Computer Engineering and Applications Journal Vol 6 No 3 (2017)
Publisher : Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (820.64 KB) | DOI: 10.18495/comengapp.v6i3.219

Abstract

Color recognition and angle detection of underwater objects can be done with the help of underwater robots (ROV) with image processing applications. The processing of the object's image is recognizing various shapes and colors of objects in the water. In this research, the color filtering and Harris corner method will be designed, studied, tested and implemented. The color filtering method is used to recognize object color patterns, while the Harris Corner method is used to detect angles of underwater objects. Then classify images to get data on environmental pattern recognition. The color patterns tested include red, green, yellow and blue. the results obtained are all color patterns can be recognized well. while the shape of the object being tested includes cubes, triangles, rectangles, pentagons, and hexagons. the results of testing some of the shapes can be detected with a good angle and others still have errors. This is because testing the form of objects is done in various positions, such as from the front, right, left, up and below.