We present an improved hybrid genetic algorithm to solve the two-dimensional Eucli-dean traveling salesman problem (TSP), in which the crossover operator is enhanced with a local search. The proposed algorithm is expe...We present an improved hybrid genetic algorithm to solve the two-dimensional Eucli-dean traveling salesman problem (TSP), in which the crossover operator is enhanced with a local search. The proposed algorithm is expected to obtain higher quality solutions within a reasonable computational time for TSP by perfectly integrating GA and the local search. The elitist choice strategy, the local search crossover operator and the double-bridge random mutation are highlighted, to enhance the convergence and the possibility of escaping from the local optima. The experimental results illustrate that the novel hybrid genetic algorithm outperforms other genetic algorithms by providing higher accuracy and satisfactory efficiency in real optimization processing.展开更多
目的探讨非心脏外科择期手术患者手术室发生高血压危象的影响因素。方法选择2021年6月~2022年6月在我院行非心脏择期手术,入手术室发生高血压危象(血压超过180/110 mm Hg),导致择期手术延迟的患者为病例组。采用1∶3配对病例-对照研究设...目的探讨非心脏外科择期手术患者手术室发生高血压危象的影响因素。方法选择2021年6月~2022年6月在我院行非心脏择期手术,入手术室发生高血压危象(血压超过180/110 mm Hg),导致择期手术延迟的患者为病例组。采用1∶3配对病例-对照研究设计,选择同期未发生入手术室高血压危象的患者为对照组。采用单因素分析和多因素logistic回归分析筛选手术室发生围术期高血压危象的影响因素。结果单因素分析显示BMI、术前高血压分级、高血压危险分层、低密度脂蛋白、脑血管疾病史差异有显著性(P<0.05)。将有显著性差异的变量纳入多因素logistic逐步回归分析,结果显示术前2级高血压(OR=39.316,P=0.031)、3级高血压(OR=102.042,P=0.008)、脑血管疾病史(OR=3.482,P=0.015)、低密度脂蛋白水平升高(OR=1.504,P=0.007)是入手术室发生高血压危象的独立影响因素。结论患者术前较高的高血压分级(2级或3级)、脑血管疾病史、低密度脂蛋白水平升高是非心脏外科择期手术患者入手术室发生高血压危象的影响因素。展开更多
文摘We present an improved hybrid genetic algorithm to solve the two-dimensional Eucli-dean traveling salesman problem (TSP), in which the crossover operator is enhanced with a local search. The proposed algorithm is expected to obtain higher quality solutions within a reasonable computational time for TSP by perfectly integrating GA and the local search. The elitist choice strategy, the local search crossover operator and the double-bridge random mutation are highlighted, to enhance the convergence and the possibility of escaping from the local optima. The experimental results illustrate that the novel hybrid genetic algorithm outperforms other genetic algorithms by providing higher accuracy and satisfactory efficiency in real optimization processing.
文摘目的探讨非心脏外科择期手术患者手术室发生高血压危象的影响因素。方法选择2021年6月~2022年6月在我院行非心脏择期手术,入手术室发生高血压危象(血压超过180/110 mm Hg),导致择期手术延迟的患者为病例组。采用1∶3配对病例-对照研究设计,选择同期未发生入手术室高血压危象的患者为对照组。采用单因素分析和多因素logistic回归分析筛选手术室发生围术期高血压危象的影响因素。结果单因素分析显示BMI、术前高血压分级、高血压危险分层、低密度脂蛋白、脑血管疾病史差异有显著性(P<0.05)。将有显著性差异的变量纳入多因素logistic逐步回归分析,结果显示术前2级高血压(OR=39.316,P=0.031)、3级高血压(OR=102.042,P=0.008)、脑血管疾病史(OR=3.482,P=0.015)、低密度脂蛋白水平升高(OR=1.504,P=0.007)是入手术室发生高血压危象的独立影响因素。结论患者术前较高的高血压分级(2级或3级)、脑血管疾病史、低密度脂蛋白水平升高是非心脏外科择期手术患者入手术室发生高血压危象的影响因素。