Abstract. The use of locks has a history thousands years. Barbed-spring padlocks are the typical used in ancient China and can be divided into three main types, namely open-keyhole, hidden-keyhole, blocked-keyhole padlocks. Since mechanical structures differ terms opening process, they reconfigurable mechanisms. With combinations changes springs, keys, keyholes, have variety different unlocking...

The stirring effect of a rotating laser on molten pool can expand the range heat source and effectively inhibit defects such as pores improve quality weld joint. Due to rotation, physical characteristics dynamic behavior keyhole are more complicated than those conventional welding. This paper adopts numerical simulation method. A three-dimensional model is developed, which takes into account co...

Keyhole plasma arc welding is a unique arc welding process for deep penetration. To ensure the quality of the welds, the presence of the keyhole is critical. Understanding of the keyhole will certainly benefit the improvement of the process and weld quality. Currently, the size of the keyhole is assumed to be correlative with the robustness of the keyhole process in maintaining the keyhole. To ...

OBJECTIVE To select a surgical approach for aneurysm clipping by comparing 2 approaches. MATERIALS AND METHODS 204 patients diagnosed with subarachnoid hemorrhage treated by the same neurosurgeon at a single institution from November 2011 to October 2013, 109 underwent surgical clipping. Among these, 40 patients with Hunt and Hess or Fisher grades 2 or lower were selected. Patients were assig...

PURPOSE It is aim to test the hypothesis that a dynamic keyhole MRI reconstruction technique using external/internal respiratory surrogate position reduces acquisition time while retaining image quality for real-time tumor monitoring, compared to the conventional keyhole technique. METHODS 46 thoracic MRI studies with 13 healthy human subjects have been acquired using a 3T GE MRI. Acquired MR...

In the magnetically controlled Plasma-GMAW welding process, composite arc forms a keyhole in workpiece to be welded. order explore effect of process parameters on coupling, weld pool and keyhole, behavior characteristics side information were collected using acquisition system high-speed camera during bead-on-plate welding. The image is processed by pseudo-color enhancement technology, molten a...

AIM Traditional craniotomies for treatment of the aneurysms at the A3 segment of anterior cerebral artery (A3As), such as frontal approach and interhemispheric approach, require pre-hairline incision and relatively long incision, extensive bone flap, inevitable supraorbital nerve injury, opening frontal sinus, and increased operative time. Here we reported anterior interhemispheric keyhole appr...

The relationships between the acoustic signal and the modes of the welding pool, such as no-keyhole (melt-in), keyhole and cutting, in variable-polarity plasma arc welding are investigated. The Welch power spectral density (PSD) estimate and short-time Fourier transformation are implemented to analyse and identify the diVerent modes of the welding pool. The results show that the no-keyhole mode...