In this paper, the fractional order differential terms are introduced into a horizontal nonlinear dynamics model of cold mill roller system. The resonance characteristics system under high-frequency and low-frequency excitation signals investigated. Firstly, dynamical equation with is established by replacing normal damping term term. Secondly, fast-slow variable separation method to solve equa...

In an estuarine system, the flood tidal wave may become a tidal bore during the early flood tide in a narrow funnelled channel under large tidal ranges. Herein new experiments were conducted in a large flume to investigate breaking tidal bores and the bore roller propagation. The results demonstrated several key features of tidal bores propagating in rectangular channels. The propagation of the...

Two types of computer input devices, a conventional mouse and a roller bar one, were studied in terms of muscular activity in m. trapezius dexter, m. deltoideus anterior dexter and m. extensor digitorum dexter, and comfort rating. Fifteen university students and employees participated in this study. The order of the devices was random. While a task was performed, electromyography (EMG) data wer...

Hands-on laboratory instruction is essential to improve student learning in engineering education. In the area of CAD/CAM/Manufacturing Technology lab courses, the high cost of commercial CNC machines like mills and lathes limits the quantity of machines accessible to the students. In this paper, a low-cost, build-your-own (BYO) three axis vertical computer numerical control (CNC) mill prototyp...

This work aims at comparing different preparation chains to produce wood powders suitable for further gasification in an entrained flow reactor. Three powders, with particle size below 1 mm, have been produced pilot scale from resinous chips: a powder of raw and torrefied both ground knife mill, vibration mill. The respective requirements energy feedstock material resource determined each chain...

in this paper a new isolating system is introduced for short to mid-rise buildings. in comparison to conventional systems such as lrb and hrb, the proposed system has the advantage of no need to cutting edge technology and has low manufacturing cost. this system is made up of two orthogonal pairs of pillow-shaped rollers that are located between flat bed and plates. by using this system in two ...

A novel method for large-scale culture of anchorage-dependent cells is described. Culture vessels were constructed by using roller bottles and Pyrex tubing. Parallel glass tubes, equally spaced by silicone rings and inserted into the roller bottles, provided an increased culture area. The roller bottles were fitted with a second opening for medium recirculation. Culture vessels of 1,000-, 4,000...

CONTEXT The identification and evaluation of activities capable of dislodging calyceal renal calculi require a patient surrogate or validated functional pyelocalyceal renal model. OBJECTIVE To evaluate roller coaster facilitation of calyceal renal calculi passage using a functional pyelocalyceal renal model. METHODS A previously described adult ureteroscopy and renoscopy simulator (Ideal An...

A 14 month retrospective study was undertaken to determine the cost implications of the opening of a roller skating rink to the local hospital accident and emergency department (A and E). A total of 398 patients attended following injury at the roller skating rink, of whom 384 were included in the study. The estimated cost of their injuries was determined by the hospital accounts department. Th...