Nacrtak In Turkey ground base skidding method is frequently used to extract log material. Physical damages occurring on the skidded log during ground based skidding cause quality and quantity loss of the log. This damage is formed by the ground structure, mass of transported logs, friction coefficient and skidding distance. In this study to improve a »Damage Prediction Model« means to predict t...

Based on the mechanical model, friction loss between ball and raceway along major axis of contact ellipse is analyzed. The result shows that this part accounts for about 13.67% overall loss, which mainly determined by sliding length cannot be ignored. effects radial force, torque, rotational speed groove curvature ratio are all studied. Compared with other factors, force has greatest influence ...

Following a recession, the aggregate labor market is slack–employment remains below normal and recruiting efforts of employers, as measured by help-wanted advertising and vacancies, are low. A model of matching friction explains the qualitative responses of the labor market to adverse shocks, but requires implausibly large shocks to account for the magnitude of observed fluctuations. The incorp...

Similarity of equations of motion for the classical and quantum trajectories is used to introduce a friction term dependent on the wavefunction phase into the time-dependent Schrödinger equation. The term describes irreversible energy loss by the quantum system. The force of friction is proportional to the velocity of a quantum trajectory. The resulting Schrödinger equation is nonlinear, conser...

The average bed shear stress and bed friction factor of samples with any roughness was derived from the head loss between upstream and downstream of a test section in an erosion tunnel. The method was validated in both hydraulically smooth (plexiglass; Reynolds number less than 25,000) and rough regimes (calibrated particles with known roughness). As a first step toward using this method on nat...

Friction welding is a solid state bonding technique which utilizes the heat generated by rubbing of two faying surfaces for the coalescence of material. Friction welding process is normally considered as a multi-input and multi-output process. Optimization of friction welding parameters is required to get good quality joints. Present study establishes the relationship between the input variable...

Welfare Implications of India’s Employment Guarantee Programme with a Wage Payment Delay* We examine the efficacy of a popular anti-poverty programme, namely the National Rural Employment Guarantee Act (NREGA) of the Government of India. We argue that a chronic friction of wage payment delay in this flagship programme could adversely affect the welfare of the poor through two channels. First, i...

This paper presents the results of an experimental study on capillary tubes commonly used as expansion device in household refrigerators and freezers. The experiments were performed with HFC-134a at different condensing pressures and level of subcooling. The pressure and temperature profiles along the capillary tubes were measured in each test run. The data set was then used to evaluate the sui...

We investigate the influence of low-energy recoils with respect to the electronic excitation of solids generated in atomic collision cascades. It is found that the electronic friction experienced by recoil atoms moving with kinetic energies below 10 eV contributes substantially to the total excitation energy dissipated into electronic degrees of freedom. The collision dynamics, on the other han...

Original scientific paper In this paper, the results of investigations of the temperature field distribution and tool wearing during C60 steel turning are presented. Abrasive wear resistance tests were carried out for cutters made of low-alloy high-speed steel. Steel samples were heat treated, and then were subjected to ion nitriding, TiN coating, or to complex treatment. The influence of cutti...