This paper aims at identifying the differences human, and inexperienced people could easily perform good between skilled and unskilled welders by analyzing the position welds. These are important considering the scarcity of skilled data obtained with a 3D motion capture system. Using the welding personnel and for reducing the costs of captured position data of various markers on the arm of the manufacturing. welder and the welding torch, the tip point position of the torch, With a human assist welding robot system (Fig. 1), the the elbow angle and roll angle of the human arm are h constructed. These constructed values are analyzed. The time human can control the process (adjust the variables and domain analysis reveals that a skilled welder has better control maintain proper torch speed and positioning) while the robot over 1) the movement of the torch tip in the perpendicular assists the human in suppressing uncontrolled vibrations, direction to the welding line, 2) the height of the torch tip from avoiding a priori known improper movements of the torch, the welded material, and 3) the speed of welding through the providing the power for lifting the torch, and placing the welding line. The frequency analysis shows that the amount and torch in awkward positions. This paper aims at determining amplitude of vibrations are larger with the unskilled welders. t The statistical analysis reveals that the difference of variation of the uncontrolled vibrations and improper torch movements in the parameters between the skilled and unskilled welders is the welding of an unskilled welder in comparison to a skilled significant.one. The knowledge derived from such a study can be used to control the human assist welding robot. Harada et al. I. INTRODUCTION(2002) have briefly reported a study on measurement of A successful arc welding necessitates managing three manual welding skills. They have concluded that an expert is phases of the process in an optimal way: Setting the able to maintain a stable motion of the torch and adapt to the parameters (initial voltage) and selecting the materials changing welding current, but an unskilled welder is not. (shielding gas, filling material) before the welding; adjusting It is hypothesized that the skill to minimize uncontrolled the variables while welding (voltage, wire feed rate); and vibrations and maintain a regular torch speed profile are the maintaining the torch position, orientation and speed during two important differences between a skilled an unskilled the welding (Pires et al., 2006). This paper is concerned with welder. This paper aims at identifying the characteristics the third phase, namely maintaining the torch position and (magnitude, frequency, range) of these features by collecting speed throughout welding. and comparing the position profile data of a number of Fully automated robots are widely used for welding in the skilled and unskilled welders. The position data of the industry (Pires et al., 2003; Yagi, 2004; Lima II et al., 321). various parts of the human arm...
Genetically encoded voltage indicators (GEVIs), particularly those based on microbial rhodopsins, are gaining traction in neuroscience as fluorescent sensors for imaging voltage dynamics with high-spatiotemporal precision. Here we establish a novel GEVI candidate based on the recently discovered subfamily of the microbial rhodopsin clade, termed heliorhodopsins. We discovered that upon excitation at 530-560nm, wild type heliorhodopsin exhibits near infra-red fluorescence which is sensitive to membrane voltage. We characterized the fluorescence brightness, photostability, voltage sensitivity and kinetics of wild type heliorhodopsin in HEK293T cells and further examined the impact of mutating key residues near the retinal chromophore. The S237A mutation significantly improved the fluorescence response of heliorhodopsin by 76% providing a highly promising starting point for further protein evolution.
Objectives:To determine the diagnostic value for predicting cerebral hyperperfusion syndrome (CHS) by adding a transcranial Doppler (TCD) measurement in the early postoperative phase after carotid endarterectomy (CEA).Design: Patients who underwent carotid endarterectomy between January 2004 and August 2010 and in whom both intra-and postoperative TCD monitoring were performed were included.Methods: In 184 CEA patients the mean velocity (V mean ) preoperatively (V 1 ), pre-clamping (V 2 ), post-declamping (V 3 ) and postoperatively (V 4 ) was measured using TCD. The intra-operative V mean increase ((V 3 Ϫ V 2 )/V 2 ) was compared to the postoperative increase ((V 4 Ϫ V 1 )/V 1 ) in relation to CHS. CHS was diagnosed if the patient developed neurological complaints in the presence of a preoperative V mean increase Ͼ100%.Results: Sixteen patients (9%) had an intra-operative V mean increase Ͼ100% and 22 patients (12%) a postoperative V mean increase of Ͼ100%. In 10 patients (5%) CHS was diagnosed; two of those had an intra-operative V mean increase of Ͼ100% and nine postoperative V mean increase Ͼ100%. This results in a positive predictive value of 13% for the intra-operative and 41% for the postoperative measurement.Conclusions: Besides the commonly used intra-operative TCD monitoring additional TCD measurement in the early postoperative phase is useful to more accurately predict CHS after CEA. Unselected Percutaneous Access with Large Vessel Closure for Endovascular
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