Background: This study aims to better understand diagnosing and treating arterial gastrointestinal fistulas. Methods: The diagnosis and treatment of two patients with arterial gastrointestinal fistulas were reported, ...Background: This study aims to better understand diagnosing and treating arterial gastrointestinal fistulas. Methods: The diagnosis and treatment of two patients with arterial gastrointestinal fistulas were reported, and the experience with diagnosis and treatment was summarized. Results: In these two cases, both patients were admitted with bleeding as the primary complaint, both underwent emergency laparotomies, and both patients were diagnosed with small intestinal bleeding before surgery. the first patient died as a result of an abdominal aortic aneurysm rupture caused by chronic vascular repair and postoperative implant infection;the second patient underwent vascular repair on time, we treated him with third-generation cephalosporin, and after he was stabilized, we performed left total iliac stent placement and left internal iliac artery embolization;he had no fever after surgery, his incision was healed, and he was successfully discharged from the hospital. Conclusion: Aortic gastrointestinal fistula is rare and has a high mortality rate, attention should be paid to distinguishing it from small intestinal bleeding. Timely diagnosis and rapid surgical treatment are keys to improving survival.展开更多
With the development of new energy,the primary frequency control(PFC)is becoming more and more important and complicated.To improve the reliability of the PFC,an evaluation method of primary frequency control ability(...With the development of new energy,the primary frequency control(PFC)is becoming more and more important and complicated.To improve the reliability of the PFC,an evaluation method of primary frequency control ability(PFCA)was proposed.First,based on the coupling model of the coordinated control system(CCS)and digital electro-hydraulic control system(DEH),principle and control mode of the PFC were introduced in detail.The simulation results showed that the PFC of the CCS and DEH was the most effective control mode.Then,the analysis of the CCS model and variable condition revealed the internal relationship among main steam pressure,valve opening and power.In term of this,the radial basis function(RBF)neural network was established to estimate the PFCA.Because the simulation curves fit well with the actual curves,the accuracy of the coupling model was verified.On this basis,simulation data was produced by coupling model to verify the proposed evaluation method.The low predication error of main steam pressure,power and the PFCA indicated that the method was effective.In addition,the actual data obtained from historical operation data were used to estimate the PFCA accurately,which was the strongest evidence for this method.展开更多
文摘Background: This study aims to better understand diagnosing and treating arterial gastrointestinal fistulas. Methods: The diagnosis and treatment of two patients with arterial gastrointestinal fistulas were reported, and the experience with diagnosis and treatment was summarized. Results: In these two cases, both patients were admitted with bleeding as the primary complaint, both underwent emergency laparotomies, and both patients were diagnosed with small intestinal bleeding before surgery. the first patient died as a result of an abdominal aortic aneurysm rupture caused by chronic vascular repair and postoperative implant infection;the second patient underwent vascular repair on time, we treated him with third-generation cephalosporin, and after he was stabilized, we performed left total iliac stent placement and left internal iliac artery embolization;he had no fever after surgery, his incision was healed, and he was successfully discharged from the hospital. Conclusion: Aortic gastrointestinal fistula is rare and has a high mortality rate, attention should be paid to distinguishing it from small intestinal bleeding. Timely diagnosis and rapid surgical treatment are keys to improving survival.
基金supported by the Electric Power Research Institute of State Grid Corporation of China in Zhejiang province。
文摘With the development of new energy,the primary frequency control(PFC)is becoming more and more important and complicated.To improve the reliability of the PFC,an evaluation method of primary frequency control ability(PFCA)was proposed.First,based on the coupling model of the coordinated control system(CCS)and digital electro-hydraulic control system(DEH),principle and control mode of the PFC were introduced in detail.The simulation results showed that the PFC of the CCS and DEH was the most effective control mode.Then,the analysis of the CCS model and variable condition revealed the internal relationship among main steam pressure,valve opening and power.In term of this,the radial basis function(RBF)neural network was established to estimate the PFCA.Because the simulation curves fit well with the actual curves,the accuracy of the coupling model was verified.On this basis,simulation data was produced by coupling model to verify the proposed evaluation method.The low predication error of main steam pressure,power and the PFCA indicated that the method was effective.In addition,the actual data obtained from historical operation data were used to estimate the PFCA accurately,which was the strongest evidence for this method.