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Background: This paper reports on the torques developed in the shoulder joint experienced by occupants of moving vehicles during manual handling tasks. Handling heavy weights can cause musculoskeletal injuries, especially if handling is done with arms extended or at high levels.Objective: The aim of the study was to measure the longitudinal and lateral accelerations in a variety of passenger vehicles together with the postures of subjects lifting luggage onto storage shelves. This data enabled the application of inverse dynamics methods in a non-inertial reference frame to calculate the shoulder joint torques.Methods: The subjects lifted 3 pieces of luggage of masses of 5 kg, 10 kg and 14 kg onto shelving which were at heights of 1.2 m, 1.6 m and 1.8 m. The movement of subjects was measured using a 12 camera, 3-dimensional optical tracking system. The subjects stood on force plates to measure the ground reaction forces.Results: Sixty-three trials were completed, although 9 trials were aborted because subjects felt unable to complete the task. It was found that the shoulder torques exceeded the levels recommend by the UK Health and Safety Executive for manual handling. A lift assistance device is suggested to reduce the shoulder torques required for luggage handling. [ABSTRACT FROM AUTHOR]

In this paper, first we introduce a new notion of pseudo anti-commuting for real hypersurfaces in complex two-plane Grassmannians G 2 ( C m + 2 ) and prove a complete classification theorem, which gives a shrinking Ricci soliton with potential Reeb flow on Hopf real hypersurfaces and a tube over a totally real totally geodesic Q P n , m = 2 n in G 2 ( C m + 2 ) . [ABSTRACT FROM AUTHOR]

Abstract: Most existing damage characterization exercises require explicitly defined material properties, geometric parameters and boundary conditions of the object to be evaluated. However, satisfying such a rudimental prerequisite can be a challenging task in reality. It may be somewhat difficult or even impossible to exactly acquire these parameters beforehand in some occasions, especially when the object comprises various structural components of distinct material/geometric properties and different boundary conditions. A damage characterization strategy, residing on a multi-scale pseudo-force damage model, was developed with an aim of achieving robust damage evaluation by tolerating ignorance of the knowledge on partial material/structural properties and boundary conditions of the object a priori. Proof-of-concept validation was carried out numerically and experimentally by characterizing a fine crack in an Euler–Bernoulli beam, a structural component included in a system with irregular boundaries, without knowing its material and structural parameters beforehand. Exact characterization results demonstrated the effectiveness and accuracy of the proposed approach. [Copyright &y& Elsevier]

In this study, Citrus sinensis (C. sinensis) solid waste was used to catalyze the conversion of free cyanide (F-CN) under alkaline conditions; conditions which represent most industrial wastewater containing F-CN. Acid hydrolysis of the solid waste increased the catalytic conversion of F-CN by 3.86 compared to the unhydrolysed solid waste. The conversion of F-CN using unhydrolysed and hydrolysed solid waste increased linearly with an increase in pH and temperature. The maximum catalytic conversion of a 100 mg F-CN/L solution containing 0.1% (w/v) of unhydrolysed and hydrolysed C. sinensis solid waste was 17.82% and 62.48%, respectively, at a pH of 12 and a temperature of 50 °C. The catalytic process was largely dependent on the availability of activated hydroxyl groups in the solid waste. As most wastewater contains heavy metals, it was determined that the presence of metallic species (Ni, Zn, and Cu) reduced the conversion of F-CN as the metallic ions attached to the hydroxyl groups. The observed reduction was 26.35% when 10 mg/L of heavy metals were present in the F-CN solution containing the hydrolysed solid waste at a pH of 12 and 40 °C. [ABSTRACT FROM AUTHOR]

Conventional force display systems provide a force sensation by applying force to the operator's body via actuators such as electric motors. These systems can potentially harm the operator, especially when providing a large force sensation. This study shows that constrictive pressure on the distal part of the forearms provides a force sensation such as holding a heavy object or pushing a wall when the pressure changes in accordance with the hand motion. This force display provides a large force sensation of ~10 N without applying real force to the operator's hand, which makes the system intrinsically safe and suitable as a wearable force display system. Experimental results show that the discrimination thresholds are consistent with Weber's Law. It was demonstrated that an operator could sort virtual objects by weight using this system. [ABSTRACT FROM AUTHOR]

Abstract: The pseudo-bistable phenomenon already shown to exist in the case of spherical domes is demonstrated in pre-stressed composite panels. This new concept for morphing structures uses intrinsic material viscoelasticity to actuate the structure passively between its different states. A pseudo-bistable structure is first snapped into a buckled state and allowed to relax under a constant strain. Once the actuation is removed, the structure remains in its buckled configuration for a period of time, before quickly returning to its initial state. In this paper, the principles of the pseudo-bistable behaviour are first outlined using a discrete truss model. An equivalent numerical model is then used to show how the time-dependent behaviour imparted to the structure can be controlled by the choice of the pre-straining boundary conditions. Next, the effect of a composite layup on the pseudo-bistable behaviour is shown, and a volume fraction limit is given. Finally, preliminary experimental results confirm the numerical simulations. [Copyright &y& Elsevier]

This paper presents a CMOS inverter-based class-AB pseudo-differential amplifier comprising current-mode common-mode feedback (CMFB). The circuit employs two CMOS inverters and the complementary CMFB consisting of current-mode common-mode (CM) detector and transimpedance amplifier. The circuit has been designed using 0.18 μm CMOS technology and operates at 1 V supply. The simulation results demonstrate rail-to-rail operation with low CM gain (−15 dB). The power dissipation of the circuit is 102.5 μW. [ABSTRACT FROM AUTHOR]

The preference of even approximations of the surface pseudo source method for calculation of the diffusion coefficient is substantiated. The homogenization limit for the G approximation in the case of the cell size tending to zero is analytically proved. [ABSTRACT FROM AUTHOR]

Complementary Work and the Force Method are developed for the analysis of plates and shells. A quadrilateral element is conceived with 4 nodes and nodal unknowns the 3 forces and 3 moments in a global coordinate system. A stress plate and shell theory is developed based on variational arguments which yields in its discrete form the global nodal forces and moments. The Force matrix of the element is established and force equilibrium postulated. The theory accepts applied displacements and rotations but applied loads or moments can be inserted as boundary conditions. The solution of the linear system of equations provide the internal loads. After solution, the displacement/rotation field can be estimated on an element basis. Numerical examples on a membrane specimen and plates and shells are provided. [ABSTRACT FROM AUTHOR]

The present work is an extension of the work that appeared in the article titled "Pseudorandom Pattern Generation by a 4-Neighborhood Cellular Automata (4NCA) using a Probabilistic Analysis". In this paper we propose a probabilistic analysis based technique for selecting good CA rules that can be used in pseudo random pattern generation. The proposed technique is applied on a CA of neighborhood four to construct one dimensional, non-uniform 4NCA random number generators. Another set of 4NCA random number generators were evolved using Cellular Programming (CP), a technique proposed by Tomassini and Sipper. A comparison is made between the pseudo random patterns generated by the proposed method and those obtained using CP. The results show that our approach outperforms CP both in terms of average time taken to evolve CA rules and in terms of quality of pseudo random patterns generated. The proposed approach is also shown to be better than the common generators such as Shift Register, Congruential Generator and Lagged Fibonacci Generator. [ABSTRACT FROM AUTHOR]

Abstract: Fundamental principles from structural dynamics, pseudo excitation method and pseudo force method are used to develop a new fast stochastic method for seismic response analysis of non-proportionally damped system. In the method, the mathematical equation of non-proportionally damped system is expressed in the iterative form, based on which the inverse operation of the matrices is avoided. Moreover, the new method does not need the solution of any complex eigenvalue problem, in contrast to other methods found in the literature. [Copyright &y& Elsevier]

We concisely derive the Coriolis force from the motions of a mass point on a smooth circular plate, which rotates with a constant angular velocity around its central axis perpendicular to the plate. The derivation of the Coriolis force is the way of general physics, which is easily understood. [ABSTRACT FROM AUTHOR]