investigations on vibration behaviors of railway track systems were attempted in this research. this was made by conducting a comprehensive field investigation into the free vibration of track systems and response of tracks to train moving loads. in-situ modal analysis was used in a railway track field as an efficient method of investigating dynamic properties of railway track systems. natural ...

Abstract: Modal analysis is a powerful technique for understanding the behavior and performance of structures. Modal analysis can be conducted via artificial excitation, e.g. shaker or instrument hammer excitation. Input force and output responses are measured. That is normally referred to as experimental modal analysis (EMA). EMA consists of three steps: data acquisition, system identificatio...

Stres kerja menjadi perhatian khusus yang telah berkembang di banyak perusahaan. Ini dapat berakibat kerugian bagi perusahaan bila tidak ditangani dengan benar. Karyawan memiliki tingkat stres tinggi dan berkepanjangan akan berniat meninggalkan karena modal psikologis, sosial manusia tangguh mampu menangani beban tuntutan pekerjaan. Tujuan dari studi ini adalah mengetahui keterkaitan antara sos...

The present study set out to investigate the effect of teaching substitution as a kind of grammatical cohesion on the true identification of confusing substitution elements with cohesive or non-cohesive roles in different contexts and also the production of modal, reporting and conditional contexts through clausal substitution acquaintance. To this end, the following procedures were taken. Firs...

An approximate numerical mthod is presented for analysis and determination of modal characteristics in straight, pretwisted non-unifom helicopter blades. The analysis considers the coupled flapwise bending (out of plane), chordwise bending (in plane), and torsion vibration of both rotating and non-rotating blades. The proposed method is based on the integral expansion of Green functions (struct...

the occurrence of chatter vibrations in boring operation has a great influence in improving workpiece dimensional accuracy, surface quality and production efficiency. in this paper instability analysis of machining process is presented by dynamic model of boring machine. this model, which consists of machine tool’s structure, is provided by finite element method and ansys software. the model is...

impulsive and convective frequencies are one of the most important subjects for evaluation of the seismic behavior of tanks. these two frequencies are defined by housner and used for obtaining rayleigh damping in time history analysis. aci 350 and nzsee standards have suggested some analytical solutions for finding convective and impulsive frequencies. these frequencies can also extract from mo...