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"This fully revised and updated third edition covers the physical and mathematical fundamentals of vibration analysis, including single degree of freedom, multi-degree of freedom, and continuous systems. A new chapter on special topics that include motion control, impact dynamics, and nonlinear dynamics is added to the new edition. In a simple and systematic manner, the book presents techniques that can easily be applied to the analysis of vibration of mechanical and structural systems. Suitable for a one-semester course on vibrations, the book presents the new concepts in simple terms and explains procedures for solving problems in considerable detail. It contains numerous exercises, examples and end-of-chapter problems."

"Tesis ini menampilkan perilaku konvergensi dari elemen 3 nodal (Triangular Free Formulation) yang dikembangkan oleh Bergan dan Felippa (1985; 1987) berdasarkan teknik formulasi bebas pada pelat FGM sandwich. Dilakukan studi numerik dengan berbagai jenis konfigurasi material, bentuk geometri, kondisi batas, serta indeks power-law. Selain itu, digunakan beberapa nilai scaling parameter untuk melihat pengaruhnya terhadap kecepatan konvergensi elemen. Hasil studi numerik menunjukkan elemen ini memiliki akurasi yang baik ketika dibandingkan dengan elemen DKMT (Discrete Kirchhoff-Mindlin Triangular) serta hasil referensi dari penelitian sebelumnya. Penggunaan scaling parameter tidak merusak konvergensi elemen dan hanya mempengaruhi kecepatan konvergensinya. Perubahan indeks power-law mempengaruhi kekakuan dari pelat, di mana semakin tinggi nilainya akan membuat kekakuan pelat semakin kecil. Hal ini terlihat dari hasil perpindahan yang semakin membesar dan frekuensi alami yang semakin mengecil.

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This thesis presents the convergence behavior of 3-node element developed by Bergan and Felippa (1985; 1987) based on free formulation technique on FGM sandwich plate. Numerical studies were done using various material configurations, geometries, boundary conditions, and power-law indexes. Furthermore, several scaling parameter values were used to observe its effect on the convergence rate of the element. The numerical studies showed that this element has good accuracy when compared to DKMT (Discrete Kirchhoff-Mindlin Triangular) element and reference results from previous researches. The use of the scaling parameter didn’t destroy the convergence of the element and only affects its rate. The change of the power-law index affects the stiffness of the plate, where the higher the value will decrease the stiffness of the plate. It can be observed from the increase of the displacement and the decrease of the natural frequency of the plate."

"Pada tesis ini, dilaporkan hasil pengujian deteksi getaran di dalam air dengan menggunakan Fiber Bragg Grating (FBG) Accelerometer 3 sumbu yang terdiri dari 3 buah FBG. Pompa air digunakan sebagai sumber getaran di dalam air dengan variasi posisi dari 0 hingga 10 cm. Hasil pengujian ditampilkan dalam bentuk perubahan panjang gelombang Bragg yang direfleksikan dan frekuensi. Pada tahap pertama, pengujian dilakukan di dalam box kontainer dengan ukuran 78 cm x 56 cm x 46 cm dengan ketinggian air sebesar 17 cm. Dari hasil pengujian pertama ditunjukkan bahwa seiring pertambahan jarak, saat pompa air berada pada FBG X, Y, atau Z maka panjang gelombang Bragg FBG X, Y, atau Z mengalami perubahan paling signifikan dengan nilai R-squared di atas 98%. Pada tahap kedua, pengujian dilakukan di dalam kolam air dengan ukuran 264 cm x 163 cm x 66 cm dengan ketinggian air sebesar 24 cm. Dari hasil pengujian kedua ditunjukkan bahwa seiring pertambahan jarak, saat pompa air berada pada FBG X, Y, atau Z, panjang gelombang Bragg FBG X, Y, atau Z mengalami perubahan paling signifikan dan menurun secara linier dengan gradien dan R-sqaured sebesar 0,0114 nm/cm dan 99,77%; 0,0124 nm/cm dan 99,71%; 0,0071 nm/cm dan 99,54%. Selanjutnya seiring pertambahan jarak, perubahan frekuensi menurun secara linier dengan gradien dan R-squared berturut-turut sebesar 1,4751 Hz/cm dan 99,53%; 1,6286 Hz/cm dan 99,82%; 1,7714 Hz/cm dan 99,84% untuk FBG X, Y, dan Z. Ditunjukkan pula bahwa eiring dengan pertambahan jarak, nilai strain dan akselerasi menurun. Hak ini menyebabkan nilai frekuensi menurun oleh karena hubungan langsung dengan strain dan akselerasi dan membutuhkan waktu yang lebih lama agar gelombang getaran mencapai FBG Accelerometer. Berdasarkan hasil perubahan frekuensi yang diterima oleh FBG X pada kondisi di udara dan di dalam air, nilai frekuensi dan amplitudo mengalami penurunan yang lebih signifikan di dalam air dibandingkan pada udara oleh karena redaman getaran oleh air, menambahkan momen inertia, dan menambahkan noise pada FBG. Dari hasil perhitungan transmisi data, terdapat delay sebesar 0,044 ms dengan kecepatan internet 7,5 Mbps dan nilai delay ini masuk dalam kategori sangat baik.

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In this thesis, the results of vibration detection underwater using Fiber Bragg Grating (FBG) Accelerometer 3-axis consisted of 3 FBGs are reported. Water pump is employed as vibration source with varied positions from 0 to 10 cm. The testing results are presented in the form of Bragg wavelength shift and frequency. On first stage, testing was conducted inside the container box with the dimensions of 78 cm x 56 cm x 46 cm with the water height of 17 cm. From the first testing results, it is shown that with increasing distance, when water pump is placed on FBG X, Y, and Z, Bragg wavelength of FBG X, Y, and Z has the most significant change and R-squared value above 98%. On second stage, testing was conducted inside the small pool with the dimensions of 264 cm x 163 cm x 66 cm with the water height of 24 cm. From the second testing results, it is shown that with increasing distance, when water pump is on FBG X, Y, and Z, Bragg wavelength FBG X, Y, and Z has the most significant change and decreases linearly with successive gradients and R-squared values of 0,0114 nm/cm and 99,77%; 0,0124 nm/cm and 99,71%; 0,0071 nm/cm and 99,54%. It is also shown that with increasing distance, the frequency decreases linearly with successive gradients and R-squared values of 1.4751 Hz/cm and 99.53%; 1.6286 Hz/cm and 99,82%; 1,7714 Hz/cm and 99,84% for FBG X, Y, and Z. It also shown that as distance increased, the strain and acceleration value decreased. This caused frequency value to decrease because frequency is linearly connected to strain and acceleration and it takes longer for vibration wave to reach FBG Accelerometer. Based on frequency change received by FBG X on air and inside the water, the frequency and amplitude decreased more inside the water than on air because of viscosity damping of water, increase inertia moment, and increase noice on FBG. From data transmission calculations, the delay value is 0,044 ms with the internet speed of 7,5 Mbps and this value classified as very good."

"This volume contains the contributions to the 10th International Workshop on Railway Noise, held October 18–22, 2010, in Nagahama, Japan, organized by the Railway Technical Research Institute (RTRI), Japan. With 11 sessions and 3 poster sessions, the workshop featured presentations by international leaders in the field of railway noise and vibration. All subjects relating to 1. prospects, legal regulation, and perception ; 2. wheel and rail noise ; 3. structure-borne noise and squeal noise ; 4. ground-borne vibration ; 5. aerodynamic noise and micro-pressure waves from tunnel portals ; 6. interior noise and sound barriers ; and 7. prediction, measurements, and monitoring are addressed here."

"The book discusses the recent research trends in various sub-domains of computing, communication and control. It includes research papers presented at the First International Conference on Emerging Trends in Engineering and Science. Focusing on areas such as optimization techniques, game theory, supply chain, green computing, 5g networks, Internet of Things, social networks, power electronics and robotics, it is a useful resource for academics and researchers alike."