Chronic and acute recurrent appendicitis are often underrecognized in clinical practice,particularly in patients presenting with persistent or recurrent right lower quadrant abdominal pain.It is essential to obtain a ...Chronic and acute recurrent appendicitis are often underrecognized in clinical practice,particularly in patients presenting with persistent or recurrent right lower quadrant abdominal pain.It is essential to obtain a detailed and comprehensive history from the patient,as careful questioning often reveals a history of prior attacks.Diagnosing recurrent and chronic appendicitis remains challenging,necessitating thorough history-taking,awareness of varied clinical presentations,and physical examination integrating specific maneuvers.Maintaining a high index of clinical suspicion is essential for recognizing these atypical presentations.Confirming a high pretest probability prior to surgical intervention is crucial to avoid unnecessary procedures.展开更多
文摘针对遥控水下机器人(remotely operated vehicle,ROV)的定深控制,提出了一种模糊线性自抗扰控制策略。该控制策略使用模糊控制对线性自抗扰控制器的参数进行在线整定,增强控制器的控制性能和抗扰动能力。首先,介绍了ROV的系统结构和功能;然后,建立了ROV的六自由度动力学模型,得到定深控制所需要的ROV在垂直面内的动力学模型;最后,设计了模糊线性自抗扰控制器。实验通过计算机仿真对所提控制策略与传统比例积分微分(proportional integral differential,PID)控制、线性自抗扰控制进行了对比,并将所提控制策略应用于露天水池下ROV的定深控制中。仿真结果表明,所提控制策略具有更好的控制效果,且在存在外部扰动的情况下具有较好的鲁棒性。基于露天水池的实际应用结果验证了所提控制策略的可行性。
文摘Chronic and acute recurrent appendicitis are often underrecognized in clinical practice,particularly in patients presenting with persistent or recurrent right lower quadrant abdominal pain.It is essential to obtain a detailed and comprehensive history from the patient,as careful questioning often reveals a history of prior attacks.Diagnosing recurrent and chronic appendicitis remains challenging,necessitating thorough history-taking,awareness of varied clinical presentations,and physical examination integrating specific maneuvers.Maintaining a high index of clinical suspicion is essential for recognizing these atypical presentations.Confirming a high pretest probability prior to surgical intervention is crucial to avoid unnecessary procedures.
