This paper focuses on solving a problem of improving system robustness and the efficiency of a distributed system at the same time. Fault tolerance with active replication and load balancing techniques are used. The p...This paper focuses on solving a problem of improving system robustness and the efficiency of a distributed system at the same time. Fault tolerance with active replication and load balancing techniques are used. The pros and cons of both techniques are analyzed, and a novel load balancing framework for fault tolerant systems with active replication is presented. Hierarchical architecture is described in detail. The framework can dynamically adjust fault tolerant groups and their memberships with respect to system loads. Three potential task scheduler group selection methods are proposed and simulation tests are made. Further analysis of test data is done and helpful observations for system design are also pointed out, including effects of task arrival intensity and task set size, relationship between total task execution time and single task execution time.展开更多
In endoscopic placement of multiple plastic biliary stents (PBSs),we sometimes experience proximal dislocation of the first PBS at the time of subsequent PBS insertion.We describe the case of a 79-year-old male with o...In endoscopic placement of multiple plastic biliary stents (PBSs),we sometimes experience proximal dislocation of the first PBS at the time of subsequent PBS insertion.We describe the case of a 79-year-old male with obstructive jaundice caused by cholangiocarcinoma who needed to receive multiple PBS placements for management of cholangitis.Although proximal dislocation of the first PBS was observed,we prevented the dislocation via our technique of using guidewire inserted from the distal end of the first PBS to the side hole as the anchor-wire.We could complete this technique only by inserting guidewire through the side hole of the first PBS during the process of releasing the first PBS and pulling out the guidewire and the inner sheath.It did not matter whether the anchor-wire went towards the third portion of the duodenum or the duodenal bulb.Here we introduce this "anchor-wire technique",which is useful for the prevention of PBS proximal dislocation in placing multiple PBSs.展开更多
文摘This paper focuses on solving a problem of improving system robustness and the efficiency of a distributed system at the same time. Fault tolerance with active replication and load balancing techniques are used. The pros and cons of both techniques are analyzed, and a novel load balancing framework for fault tolerant systems with active replication is presented. Hierarchical architecture is described in detail. The framework can dynamically adjust fault tolerant groups and their memberships with respect to system loads. Three potential task scheduler group selection methods are proposed and simulation tests are made. Further analysis of test data is done and helpful observations for system design are also pointed out, including effects of task arrival intensity and task set size, relationship between total task execution time and single task execution time.
文摘In endoscopic placement of multiple plastic biliary stents (PBSs),we sometimes experience proximal dislocation of the first PBS at the time of subsequent PBS insertion.We describe the case of a 79-year-old male with obstructive jaundice caused by cholangiocarcinoma who needed to receive multiple PBS placements for management of cholangitis.Although proximal dislocation of the first PBS was observed,we prevented the dislocation via our technique of using guidewire inserted from the distal end of the first PBS to the side hole as the anchor-wire.We could complete this technique only by inserting guidewire through the side hole of the first PBS during the process of releasing the first PBS and pulling out the guidewire and the inner sheath.It did not matter whether the anchor-wire went towards the third portion of the duodenum or the duodenal bulb.Here we introduce this "anchor-wire technique",which is useful for the prevention of PBS proximal dislocation in placing multiple PBSs.