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The conventional bridge crane hoisting control method is limited by the complex factors of working conditions and generally adopts cumbersome off-line planning. In view of the problem of the inertia swing of the load caused by the trolley hauling the lifting rope during the transportation of the bridge crane, the trajectory off-line planning methods with the open-loop bring the control parameters to be complicated and tedious. A novel trajectory online planning and under-actuated control method on positioning and anti-swing for the bridge crane is proposed. According to the smooth positioning trajectory, the relationship among the motion parameters of the trolley, load swing angle, and other model parameters in the dynamic model are analyzed. With the dynamic coupling relationship between trolley motion and load swing, the function of anti-swing is designed online without changing the positioning performance. The trajectory online planning of the positioning and anti-swaying is accomplished. With the experimental and programming, the proposed method is compared with other different planning methods. The results show that this method can effectively realize the positioning and eliminating pendulum, and has the convenience of online adjusting parameters and fast response.

The Glasgow - Blatchford bleeding score (GBS) and admission and full Rockall scores are widely used risk scoring systems to stratify risk and determine the need for intervention in patients with upper gastrointestinal bleeding. We evaluated the performance of these risk scoring systems in patients with gastric cancer and tumor bleeding.This retrospective study included patients with inoperable gastric cancer who presented with tumor bleeding at the National Cancer Center, Korea, between 2001 and 2015. The GBS, and admission and full Rockall scores were calculated. Primary outcome was the performance of the risk scoring systems in predicting the need for urgent interventions (endoscopic therapy, transarterial embolization, and surgery). The risk factors associated with urgent intervention were analyzed.Of 357 patients with tumor bleeding, 118 (33.1 %; 116 endoscopic therapy, 2 trans-arterial embolization) required urgent intervention. The full Rockall score was better at predicting the need for urgent intervention (area under the receiver operating characteristic curve = 0.78;The full Rockall score was superior to the GBS and admission Rockall score in predicting the need for urgent intervention for tumor bleeding. Thus, endoscopic evaluation is required to determine the need for urgent intervention in patients with gastric cancer and tumor bleeding.