nonlinear hunting speeds of railway vehicles running on a tangent track are analytically obtained using hopf bifurcation theory in this paper. the railway vehicle model consists of nonlinear primary yaw dampers, nonlinear flange contact stiffness as well as the clearance between the wheel flange and rail tread. linear and nonlinear critical speeds are obtained using bogoliubov method. a compreh...

Avoidance advice: This forms a very important component of treatment once a diagnosis of contact dermatitis has been made on the basis of a detailed history, examination and patch testing. Possible sources of exposure to the causative allergens should be identified and advice has to be tailored to an individual. The patient should be informed about the identification of the offending agent and ...

A 19-year-old female hairdressing student was referred because of hand eczema (Fig. 1a), which had developed during the 8 months she had been training. The history also showed an intense reaction following a ‘temporary henna tattoo’ when she was aged 15 years. Patch testing was performed, according to the ICDRG criteria, with the Spanish Contact Dermatitis Research Group baseline series (TRUE T...

A method for kinematics modeling of a six-wheel Rocker-Bogie mobile robot is described in detail. The forward kinematics is derived by using wheel Jacobian matrices in conjunction with wheel-ground contact angle estimation. Te inverse kinematics is to obtain the wheel velocities and steering angles from the desired forward velocity and turning rate of the robot. Traction Control also developed ...

A method for kinematics modeling of a six-wheel Rocker-Bogie mobile robot is described in detail. The forward kinematics is derived by using wheel Jacobian matrices in conjunction with wheel-ground contact angle estimation. The inverse kinematics is to obtain the wheel velocities and steering angles from the desired forward velocity and turning rate of the robot. Traction Control is also develo...

Background and aim: Contact dermatitis is an inflammatory skin response due to contact with environmental materials manifested as acute or chronic eczema. Patch test is the standard test to recognize responsible allergen. The objective of this study was to evaluate the frequency of false positive patch test responses in patients with Exited Skin Syndrome (ESS).Materials...

Many types of omnidirectional wheels with passive rollers have gaps between rollers. Since these gaps cause a wheel to make discontinuous contact with the ground, they lead to vertical and/or horizontal vibrations during wheel operation. In addition, the radii of passive rollers are related to the height of a bump an omnidirectional wheel can surmount. In this research a new design of the alter...