A ski jumper tries to maintain an aerodynamic position in the in-run during changing environmental forces. The purpose of this study was to analyze the mechanical demands on a ski jumper taking the in-run in a static position. We simulated the in-run in ski jumping with a 4-segment forward dynamic model (foot, leg, thigh, and upper body). The curved path of the in-run was used as kinematic cons...

A systematic study is performed of the structure of the twist–2 contributions to the virtual Compton amplitude in deep–inelastic non–forward scattering for general spin states in the non–local light cone expansion. The gauge invariance is proven in this approach for the twist–2 contributions for non–forward scattering. Relations are derived between the contributing non–forward amplitudes.

FORWARD Designing an interface between systems is not a simple or straight-forward task. Parameters that must be taken into account include: data rate, data format, cable length, mode of transmission, termination, bus common mode range, connector type, and system configuration. Noting the number of parameters illustrates how complex this task actually is. Additionally, the interface’s compatibi...

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...

UNLABELLED Background Office workers spend a long period of time behind a computer during working hours. The relation between the posture of sitting during work with computer and neck pain is still debatable. Even though some researchers claim a significant difference in head posture between patients with neck pain and pain-free participants, the FHP (forward head posture) has not always been a...

In this study, a novel acidic magnetic dicationic ionic liquid was prepared in three steps to serve as a green  catalyst  in  organic  synthesis.  The  newly  synthesized  catalyst  was  characterized UV- VIS,  and  VSM  analysis.  Additionally,  the  decomposition  steps  acatalyst  were investigated by thermal  analysis  techniques  (TGA/DSC).  The  synthesized  acidic magnetic dication...

This paper describes the mechanical configuration of a quadruped robot firstly. Each of the four legs consists of three rotary joints. All joints of the robot are actuated by linear hydraulic servo cylinders. Then it deduces the forward and inverse kinematic equations for four legs with D-H transformation matrices. Furthermore, it gives a composite foot trajectory composed of cubic curve and st...

This paper models a machine replacement and capacity expansion problem as an infinite-horizon linear program. We establish a strong duality result and show that stationary dual prices are optimal, regardless of initial conditions. These prices measure the economic value of owning vintage machinery and thus define depreciation schedules. We present necessary and sufficient conditions for straigh...