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Analisa Dinamis dan Kendali Narrow Tilting Three-Wheeled Vehicle
Full text linkKemacetan dan polusi kendaraan menjadi masalah besar terutama di kota-kota besar. Masalah ini disebabkan oleh bertambahnya jumlah kendaraan. Penggunaan mobil dengan hanya 1-2 pengendara/penumpang menjadi salah satu sumber masalah utama kemacetan dan polusi. Penggunaan sepeda motor memang lebih efisien dalam memanfaatkan ruas jalan namun memiliki tingkat keamanan yang rendah.
Salah satu solusinya adalah Narrow Tilting Three-Wheeled Vehicle (NTTWV). Kendaraan ini memiliki 3 roda dengan 2 roda di depan sebagai kemudi dan 1 roda di belakang sebagai penggerak. Sistem active tilting digunakan untuk memberikan sudut roll φ yang berfungsi untuk melawan gaya sentrifugal agar kendaraan tidak guling ketika berbelok.
Tujuan dari penelitian ini adalah membuat model dinamis dari NTTWV ketika berbelok serta mendesain sistem kendali torsi tilting agar mampu memberikan kesetabilan dan keamanan terbaik. Semua parameter kendaraan disesuaikan pada data model 3D di Autodek Inventor Student. Model kontak antara roda dan jalan yang digunakan adalah model Dugof.
Model dinamis telah berhasil divalidasi agar mampu mewakili kondisi NTTWV ketika berbelok. Nilai cornering stiffness dari model dinamis ini diambil dari rata-rata cornering stiffness model Dugoff yaitu Kf = 4208.92 N/deg dan Kr = 6635.33 N/deg. Sistem kendali didesain dengan menggunakan roll gain Kφ = 0.76. Nilai tersebut mampu memenuhi batas dari sambungan A-arm dan kinerja dalam menjaga kendaraan untuk tidak guling. Peningkatan kecepatan kritis sesaat sebelum roda terangkat dibandingkan dengan kendaraan 3 roda non-tilting pada δ = 5 derajat dan δ = 10 derajat adalah 193% dan 171%. ===================================================================================================
Congestion and pollution become major problem in urban road. The problem is caused by the increase of vehicle number. The use of vehicle with only 1-2 passenger becomes one of the most significant cause of congestion and pollution.
In the other hand, motorcycle has better efficiency in using road area, but it has low level of safety. The proposed solution for this problem is Narrow Tilting Three-Wheeled
Vehicle (NTTWV). It has 3 wheels with 2 front wheels as steering and single rear wheel as traction wheel. Active tilting system is used to generate roll angle φ that can resist the centrifugal force to stabilize the vehicle during cornering. The goals of this research are to design the dynamic model of the NTTWV during cornering and to
design its control for tilting torque to give best safety and comfort. All parameters of the vehicle are based on 3D model in Autodesk Inventor Student. Contact model between tire and road surface use Dugoff model.
The dynamic model is validated to represent the NTTWV
condition during cornering. Cornering stiffness value of this dynamic model is generated by averaging the cornering stiffness in Dugoff model: 퐾푓=4208.92푁/푑푒푔
dan 퐾푟=4208. 92푁/푑푒푔. The control system is design
ed by using rollgain 퐾휑=0.76. the roll gain can maintain the A-arm joint limit and performance to prevent the vehicle from rollout. The improvement of critical speed compared to non-tilting three-wheeled vehicle at δ=50and δ=100 are 193% and 171%
Analisis Struktural Performa Chassis Sapuangin Speed 2013
Full text linkTim Sapuangin Institut Teknologi Sepuluh Nopember (ITS) untuk pertama kalinya berpartisipasi pada Student Formula Japan (SFJ) di Shizuoka Ecopa Stadium Japan Pada Tahun 2013. Mobil yang dilombakan pada ajang Formula SAE harus memiliki Chassis yang kuat namun ringan. Chassis mobil FSAE harus kuat karena beban yang diterima sangat besar ketika akselerasi, berbelok dan ketika melakukan pengereman. Di sisi lain, Bobot dari Chassis harus seringan mungkin agar beban yang ditopang Engine menjadi minimal. Untuk mengoptimasi kekuatan dan berat dari Chassis maka perlu dilakukan simulasi numerik. Pengujian dalam tugas akhir ini didahului dengan Studi literatur pada berbagai sumber dan pengumpulan data teknis Sapuangin Speed 2013. Selanjutnya adalah perhitungan beban yang meliputti beban vertikal, torsional, akselerasi, belok dan pengereman. Langkah selanjutnya adalah proses meshing atau pemecahan model 3d Chassis menjadi elemen hingga yang kemudian diuji kualitasnya dengan Convergent test. Setelah meshing dinyatakan Convergent, barulah simulasi dilakukan dengan boundary conditions yang telah didapatkan pada proses perhitungan beban. Pengujian ini diakhiri dengan memperoleh data hasil simulasi dan mengevaluasi perbandingan hasil. Pada penelitian ini didapatkan 5 hasil simulasi dari 5 jenis pembebanan. Dari hasil simulasi beban vertikal didapatkan tegangan von mises sebesar 77.016 MPa, deformasi maksimal sebesar 0.52 mm dan angka keamanan sebesar 3.96. Dari hasil simulasi beban Torsional, pada pembebanan 0.5Wsprung didapatkan tegangan von mises sebesar 187.72 MPa, deformasi maksimal sebesar 7.63 mm, angka keamanan sebesar 1.62 dan kekakuan sebesar 946.34 Nm/o . Dari hasil simulasi beban akselerasi didapatkan tegangan von mises sebesar 186.48 MPa, deformasi maksimal sebesar 1.69 mm dan angka keamanan sebesar 1.63 Dari hasil simulasi beban belok didapatkan tegangan von mises sebesar 167.35 MPa, deformasi maksimal sebesar 1.06 mm dan angka keamanan sebesar 1.82. Sedangkan dari hasil simulasi beban pengereman didapatkan tegangan von mises sebesar 70.376 MPa, deformasi maksimal sebesar 0.44 mm dan angka keamanan sebesar 4.33. Chassis Sapuangin Speed 2013 masih belum mempunyai angka keamanan dan kekakuan yang baik dan masih perlu mendapat tambahan elemen chassis.
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Institut Teknologi Sepuluh Nopember (ITS) Sapuangin team participated in Student Formula Japan (SFJ) at Shizuoka Ecopa Stadium Japan for the first time in 2013. The car that competed in Formula SAE must have light and strength chassis. FSAE car’s chassis must be strong because some very large load received when accelerating, turning and braking. On the other hand, the weight of the chassis must be as light as possible so the load that applied to the Engine becomes minimal. To optimize the strength and weight of the chassis, numerical simulation is necessary. Analysis in this final project is preceded by literature studies on the various sources and technical data collection of Sapuangin Speed 2013. The next step is the computation load including vertical load, torsional, acceleration, turning and braking. The ext step is the process of meshing or splitting the 3d chassis model into a finite element which is then quality tested by Convergent test. After meshing Convergent declared, then the simulation is performed with the boundary conditions that have been obtained in the process of load calculation. The project is ended by acquiring data and evaluating the simulation comparison results. In this study, 5 simulation results of 5 different types of loading are acquired. From the vertical load simulation results obtained, von mises stress is 77 016 MPa, deformation is 0:52 mm and maximum safety factor is 3.96. From the Torsional load simulation results obtained, for 0.5Wsprung load, von mises stress is 187.72 MPa, the maximum deformation is 7.63 mm, the safety factor is 1.62 and stiffness is 946.34 Nm / o . From the acceleration load simulation results obtained, von mises stress is 186.48 MPa, the maximum deformation is 1.69 mm and a safety factor is 1.63 from the turning load simulation results obtained, von mises stress is 167.35 MPa, the maximum deformation is 1.06 mm and a safety factor is 1.82. From the braking load simulation results obtained, von mises stress is 70 376 MPa, deformation is 0.44 mm and maximum safety factor is 4.33. Chassis Sapuangin Speed 2013 does not have good safety factor and rigidity and still need to get an extra element of the chassis
Sistem Informasi Presensi Online Menggunakan Teknologi Face Recognition dan GPS
Full text linkSistem presensi di SMK Muhammadiyah 1 Weleri masih menggukan cara konvensional sehingga membutuhkan waktu yang lama dan rentan adanya manipulasi data maupun data ganda. Perancangan system informasi presensi online ini dibangun dengan teknologi GPS dan Face Recognition yang berbasis android dan web. Sistem ini dirancang dengan menggunakan PHP sebagai bahasa pemrograman, dan MySQL sebagai basis data. Dalam Pembuatan system pada penelitian ini penulis menggunakan metode Software Development Life Cycle (SDLC) Waterfall. Kemudian untuk pengujian menggunakan User Acceptance Testing (UAT) untuk menguji sistem terhadap spesifikasi aplikasi dengan membagikan kuisioner untuk responden. Pengujian tersebut akan dilakukan oleh guru dan karyawan di SMK Muhammadiyah 1 Weleri. Penelitian ini bertujuan untuk memudahkan pengelolaan presensi guru dan karyawan, sehingga dapat memberikan informasi secara lengkap dan akurat, serta dapat melakukan monitoring presensi tersebut dengan efektif dan efisien. Kemudian hasil dari uji sistem menggunakan User Acceptance Testing (UAT) sebesar 93,8% yang menandakan sistem ini dapat diterima oleh penggunanya
Sistem Automatic Feeder, Pemantauan Suhu dan Kendali Kadar pH di Kolam Budidaya Ikan Lele Menggunakan Aplikasi Blynk
No full textThe presence of fish farmers to control water quality and maintain consistency in feeding must of course always be at the cultivation site, this becomes a challenge if the cultivator is faced with other activities or traveling for a long period of time. Therefore, the author took the initiative to collaborate technological advances with fish culture techniques using the prototype system development method. So that the research produces products or tools based on the Internet of Things (IoT) that can be connected to smart phones through the Blynk application. The sensor used to detect temperature is DS18B20, while the pH sensor uses PH-4502C. The results obtained from this research are tools that are able to monitor temperature, control pH and feed automatically with control media via smart phones.Kehadiran pembudidaya ikan untuk mengontrol kualitas air dan menjaga konsistensi pemberian pakan tentunya harus selalu berada di lokasi budidaya, hal tersebut menjadi sebuah tantangan jika pembudidaya sedang dihadapkan dengan kesibukan lain atau bepergian dalam jangka waktu yang lama. Oleh karena itu penulis berinisiatif untuk mengkolaborasikan kemajuan teknologi dengan teknik bududaya ikan menggunakan metode pengembangan sistem prototipe. Sehingga penelitian tersebut menghasilkan produk atau alat dengan basis Internet of Things (IoT) yang dapat terhubung dengan ponsel pintar melalui aplikasi Blynk. Sensor yang dipakai untuk mendeteksi suhu adalah DS18B20, sementara untuk sensor pH menggunakan PH-4502C. Hasil yang didapat dari penelitian ini merupakan alat yang mampu memantau suhu, mengendalikan pH dan memberi pakan otomatis dengan media kontrol melalui ponsel pintar
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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