This research was conducted on Diesel engine single cylinder which aims to study the dynamic characteristics of Diesel engine type HATZ 1D 80 made in Germany. The test was performed by measuring the Frequency Response Function (FRF). In this study, the vibration response was measured at three points: point A which was situated below the engine shaft and in line with the stinger. Point A indicated the FRF point. Point B was located in the valve train component, while point C was situated above the cap of the valve train component. The range of frequencies applied was 0 - 3200 Hz, 3200 - 6400 Hz, 6400 - 9600 Hz, and 9600 - 11200 Hz. This research indicates that the natural frequencies arose because of the global vibration mode. The global vibration mode occurred at natural frequencies of 3118, 4805, 4821, 5021, 7129, 8601, and 11107 Hz. While other natural frequencies were associated with the local vibration mode because it appears only at one point of measurement.

Bearing acts as a pad that supports a shaft to rotate without excessive friction, hold the radial load and maintain the motion towards the left and right shafts (Thrust Load) when turning together. Due to frequent taper bearing damage to the wheels, predictive maintenance is therefore necessary. One of the predictive maintenance methods widely used today is vibration analysis. The principles of vibration-based bearing damage detection using the Frequency Response Function (FRF) method will be shown in this paper. Harmonics signal is given to the bearing surface in a vertical or perpendicular direction to the taper bearing surface. The vibration response measurement was carried out on three axes (x, y, and z). The results of this study indicated the ability of FRFs to predict any damage on the bearing taper.

A motorized vehicle needs a system that can not only reduce the speed and stop the vehicle but can also serve as a safety tool and ensure a safe distribution which is called a braking system. It is important to conduct maintenance of a disc brake that is part of the braking system. Therefore, this study developed a technique to inspect a 1200-cc Daihatsu Sigra disc brake through the vibration measurement using a bump test. A disc brake is comprised of three fields:  A (located next to the center of the disc brake), B ( in the middle diameter), and C ( in the outer diameter of the disc brake). Each field has ten measurement points. This study showed that disc brake damages occurring in field A were at points 1-3, and they appeared after the  250-Hz frequency. Meanwhile, in fields B and C, at all measurement points, there were no changes taking place at any frequency.

The air compressor engine is becoming a requirement for both large and small industries production machines instead of the drive system of the driven motor becomes pneumatic. In a pneumatic drive system requires certain air pressures are adjusted to the needs of the industry. Compressor engine which widely used is a screw compressor. On the screw compressor, male and female rotors in the air producer are part of the very important because as the primary producer of compressed air from the motor rotation, then the maintenance must be considered regularly, especially vibrations resulting. The study was conducted to test the amount of vibration that occurs on the screw compressor rotor from the rotor rotation variations using vibration measuring devices FFT analyzer. Measurements are made by attaching the accelerometer sensor to the x, y, and z-axis of the compressor screw rotor casing. Three variations rotors are 2557 rpm, 5042 rpm, and 7508 rpm to get a reference to the magnitude of rotation that is best used in the refrigeration machine is reviewed of the amount of vibration produced. From the results of testing and data collection, it can be concluded that vibration is measured using an FFT analyzer of vibration values the highest is at 7508 rpm which is 7.768 Hz and the lowest is at rotation 2557 rpm of 6,442 Hz. Characteristics of screw compressor vibrations in various rotation conditions can be unbalanced due to the emergence of amplitude at 1x rpm it also experiences a misalignment due to generating vibrations which are higher than usual 2x rpm.

<p>Aktivitas logistik memegang peranan penting dalam proses bisnis dimana terdapat proses <br />distribusi untuk menyalurkan produk dari produsen/penjual kepada konsumen. Saat ini<br />bermunculan semakin banyak perusahaan yang bergerak di bidang penyediaan pelayanan jasa <br />logistik, dengan berbagai kelebihan dan kekurangannya. Kondisi ini membuat pengguna jasa lebih <br />leluasa dalam menentukan pilihan, perusahaan kurir mana yang dipercaya untuk mengambil alih <br />sebagian fungsi bisnisnya.Untuk membantu pengambilan keputusan dalam pemilihan penyedia <br />jasa kurir, penulis melakukan penelitian mengenai kriteria yang digunakan pengguna jasa dalam <br />menentukan penyedia jasa terbaik. Penelitian dilakukan menggunakan metode Analytical <br />Hierarchy Process (AHP), metode AHP dipilih karena metode ini dapat membuat sebuah kerangka <br />pengambilan keputusan dengan efektif atas persoalan yang kompleks. Permasalahan yang terdiri <br />atas beberapa pertimbangan, kemudian disederhanakan ke dalam beberapa kriteria yang kemudian <br />disusunan dalam suatu hirarki.Setelah disusun dalam hierarki dapatditentukan criteria terpenting <br />yang menjadi pertimbangan utama pengguna jasa. Penelitian ini dibatasi pada perusahaan<br />penyedia jasa logistik yang bergerak pada jasa pengiriman ekspres (kurir). Reponden dibatasi pada <br />pengguna yang menggunakan jasa pengantaran barang (kurir) untuk keperluan penjualan online. <br />Tujuan penelitian ini adalah untuk mengetahui kriteria utama yang diprioritaskan sebagai <br />pertimbangan bagi pengguna jasa dalam pemilihan penyedia jasa logistik. Berdasarkan survey <br />yang dilakukan terhadap para penjual online, diketahui bahwa kriteria yang menjadi pertimbangan <br />utama dalam pemilihan jasa kurir adalah Reliability, yaitu keandalan suatu perusahaan jasa kurir<br />dalam melayani kebutuhan dan keinginan pelanggannya diikuti dengan cost (biaya pengiriman) <br />dan Convinience (kenyamanan).</p>