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"This monograph presents computational models that describe electro-mechanical characteristics of tapered and cylinder roller bearings in various industrial applications. Applying the Levenberg-Marquardts algorithm to solving strongly nonlinear coupled equation systems, the computational models consisting of many circular slices per rolling element enable computations of the local Hertzian pressures at the elastohydrodynamic (EHD) contact area, the relating oil-film thickness in elastohydrodynamic lubrication (EHL), the limiting voltage of electro-pitting, bearing frictions, and fatigue lifetimes of the bearings for various load spectra. Using the best-known machine-learning method for clustering, the load spectrum is clustered in k cluster means based on the invariant damage number to accelerate the load spectrum. Furthermore, the accelerated load spectrum is used for the testing procedure of the bearings to reduce the testing time and costs as well."

"Bearing sering kali digunakan hampir pada setiap alat terutama pada bagian yang berputar, dan hal ini menunjukkan bahwa bearing adalah bagian yang sangat penting pada mesin. Kerusakan pada bearing mengakibatkan vibrasi yang dapat menimbulkan suara yang tidak diharapkan, stress yang tinggi atau kerusakan yang pada akhirnya mengakibatkan terjadinya awal kerusakan pada sebuah mesin. Analisa tentang teknologi vibrasi memberikan informasi awal pada kerusakan sehingga memungkinkan prediksi kegagalan terhadap bearing dengan kondisi yang sudah kritis dapat beroperasi lebih lama. Prognosis ini sangat berpotensi untuk mengurangi biaya perawatan dan meningkatkan operasional dan keamanan. Prognostic bearing test rig yang sudah ada dimodifikasi, di rancang ulang, dan di manufaktur dengan tujuan mengembangkan test rig yang ada untuk memastikan keakurasian dalam memproses signal. Selain itu, test rig juga dilengkapi dengan instrumentasi serta parangkat lunak untuk analisa vibrasi dengan tujuan meningkatkan efisiensi pendataan signal."

"The selection of materials for an engineering component is not only requested by its design function and shape, but alsothe sequence through which it is manufactured. The manufacturing operation of roller chains involves drawing andtrimming processes aimed at producing semi-finished chain drives component with a well-standardized dimension. Inaddition to final combination of properties required by design constraints, the ability of materials to be formed into adesired shape and geometry without failure is also critical. The objective of materials selection should therefore involveadditional attributes that are not typically accommodated by the standard procedure of materials selection. The presentpaper deals with the selection of materials for roller chains from the perspective of manufacturing process. Ears andun-uniform wall thickness have been identified as a key problem in the mass production of component. Provided allprocess parameters were established, the anisotropy factor of materials is critical. Simulative test can be reasonablyused to obtain material performance indices that can be added up to the standard procedure of material selection. Ofthree commercially available steel grades evaluated with regard to the criteria defined, one grade is more suitable for thepresent objective."

"Roller Compacted Concrete (RCC) telah menjadi material pilihan dalam berbagai aplikasi konstruksi karena keunggulannya dalam hal kekuatan, durabilitas, dan efisiensi biaya. RCC termasuk ke dalam no-slump concrete yang memiliki konsistensi kering dan dipadatkan menggunakan alat berat seperti roller, sehingga memberikan karakteristik unik dibandingkan dengan beton konvensional. Penelitian ini bertujuan untuk mengetahui korelasi antara hasil pengujian kuat tekan dan UPV sampel silinder RCC dengan pemanfaatan 60% fly ash dan semen tipe PCC. Metode yang digunakan dalam peneltian ini adalah pengujian destruktif untuk kuat tekan beton dan pengujian non destruktif untuk UPV. Hasil dari penelitian ini adalah nilai kuat tekan sampel RCC yang meningkat seiring pertambahan cepat rambat gelombang. Sampel RCC yang diuji sampai umur 28 hari nilai kuat tekannya 2.84 MPa dan belum memenuhi target kuat tekan fc’ 15 MPa. Dari grafik hubungan kuat tekan dan cepat rambat sampel RCC didapatkan persamaan fc'(v) = 0.3392e^(0.5951v).

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Roller Compacted Concrete (RCC) has become the material of choice in various construction applications due to its advantages in terms of strength, durability, and cost efficiency. RCC is classified as no-slump concrete, having a dry consistency and compacted using heavy equipment such as rollers, thus providing unique characteristics compared to conventional concrete. This study aims to determine the correlation between the results of compressive strength and UPV testing of RCC cylinder samples with the utilization of 60% fly ash and PCC type cement. The method used in this research is destructive testing for concrete compressive strength and non-destructive testing for UPV. The result of this research is the compressive strength value of RCC samples which increases as the wave propagation speed increases. RCC samples tested until the age of 28 days the compressive strength value is 2.84 MPa and has not met the target compressive strength fc' 15 MPa. From the graph of the relationship between compressive strength and propagation speed of the RCC sample, the equation is obtained fc'(v) = 0.3392e^(0.5951v)."

"Roller Compacted Concrete (RCC) adalah beton yang memiliki keunggulan dalam hal kecepatan pelaksanaan, biaya produksi yang lebih rendah, serta penggunaan semen yang lebih rendah dibandingkan beton konvensional. RCC umumnya dimanfaatkan pada struktur bendungan dan perkerasan jalan, tetapi belum banyak diaplikasikan di Indonesia. Pada kasus bendungan, RCC dapat dikombinasikan dengan penggunaan beton konvensional untuk memberikan keuntungan yang lebih baik. Penelitian ini bertujuan untuk mengkaji korelasi hubungan antara hasil uji kuat tekan dan ultrasonic pulse velocity (UPV) pada sampel silinder beton konvensional dengan campuran Portland Slag Cement (PSC) dan Portland Composite Cement (PCC) dalam kasus konstruksi Bendungan Roller Compacted Concrete (RCC). Penelitian dilakukan dengan menggunakan metode eksperimental laboratorium, yang melibatkan pengujian destruktif berupa uji kuat tekan dan pengujian non-destruktif berupa uji UPV. Hasil penelitian ini menunjukkan bahwa hasil uji kuat tekan dan UPV memiliki korelasi yang positif dan bervariasi berdasarkan jenis campuran beton yang digunakan, yang dipengaruhi oleh faktor seperti komposisi material, rasio air-semen, kepadatan dan homogenitas campuran, serta metode pembuatan dan perawatan sampel beton.

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Roller Compacted Concrete (RCC) is concrete that has advantages in terms of speed of implementation, lower production costs, and lower cement usage compared to conventional concrete. RCC is generally used in dam structures and road pavements, but has not been widely applied in Indonesia. In the case of dams, RCC can be combined with the use of conventional concrete to provide better benefits. This research aims to examine the correlation between the results of compressive strength and ultrasonic pulse velocity (UPV) tests on conventional concrete cylinder samples mixed with Portland Slag Cement (PSC) and Portland Composite Cement (PCC) in the case of Roller Compacted Concrete (RCC) Dam construction. The research was carried out using laboratory experimental methods, which involved destructive testing in the form of compressive strength tests and non-destructive testing in the form of UPV tests. The results of this research show that the compressive strength and UPV test results have a positive correlation and vary based on the type of concrete mixture used, which is influenced by factors such as material composition, water-cement ratio, density and homogeneity of the mixture, as well as the method of making and caring for the concrete samples."