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1.
针对置换流水车间调度问题,以最小化最大完成时间为调度目标,提出了一种离散候鸟迁徙优化(Discrete Migrating Birds Optimization,DMBO)调度算法。采用NEH产生一个调度可行解,其余个体随机产生,保证了种群的质量和多样性,初始化鸟群按优化目标值升序排成倒V字形。领飞鸟通过优化插入加优化交换产生的邻域解进化,而通过混合策略获得跟飞鸟的邻域解。跟飞鸟通过其邻域解和前面个体未使用的、较好的邻域解进化,这种进化机制是独一无二的。最后,采用局部搜索算法进一步优化种群。仿真实验中使用正交设计方法调节算法参数,通过求解Car 和Rec标准算例,验证了算法的有效性。  相似文献   

2.
针对处理时间不确定情况下带并行机的混合Flow Shop调度问题,基于模糊规划理论,采用一种模糊数排序的方法建立了调度模型;以最小化加权模糊最大完工时间的平均值和不确定度作为调度目标,提出一种改进分布估计算法(IEDA)求解上述问题。 IEDA算法采用基于NEH(Nawaz Enscore Ham)和破坏重建策略的初始化方法,对较优个体进行变邻域局部搜索以提高算法的局部搜索能力,同时采用破坏重建策略增加种群多样性,在最优解连续若干代没有改进时对其进行基于破坏重建策略的变邻域局部搜索,增强算法跳出局部最优的能力,并用正交设计的方法调节算法参数。仿真实验结果验证了本文算法的优越性。  相似文献   

3.
针对批量流水线调度问题,提出了一种改进的人工蜂群算法优化最大完成时间。该算法用NEH方法产生初始解,利用混沌的遍历性生成新的邻域解。为了跳出局部最优,使用最优解插入扰动替换一些连续若干步不能改进的解以提高算法的全局搜索能力,仿真实验结果验证了算法的可行性。  相似文献   

4.
针对流水车间中产品不存在缓冲区的多目标优化问题,研究了阻塞流水车间的最大完工时间和总流程时间的最小化问题,提出了一种多目标离散差分进化(Multi-objective Discrete Differential Evolution,MDDE)算法搜索Pareto最优调度解。MDDE的变异个体通过非支配解或当前解的邻域随机产生,实验个体通过交叉操作产生,而选择过程则设计为一种多目标选择策略。此外,算法还混合了一种基于插入的Pareto局部搜索方法。基于标准测试算例的数值仿真实验表明,MDDE算法获得的非支配解集在Inverted Generational Distance、Set Coverage和Hypervolume性能指标上均有较好的表现。  相似文献   

5.
作业车间调度问题属于NP-hard问题,是离散生产制造中广泛存在的一类组合优化问题。针对此问题,提出了一种新型遗传邻域万有引力算法。该算法借鉴万有引力搜索算法中惯性质量和欧氏距离的概念,提出了候选父代染色体个数的选择方法和染色体差距的计算方法,并以此定义了一种新的交叉策略;同时混合遗传算法与N5邻域结构,有效地求解了作业车间调度问题。通过对3个FT类和10个LA类标准测试算例的仿真,验证了本文遗传邻域万有引力算法的优越性。采用遗传邻域万有引力算法有效地解决了某水表制造企业中的大规模作业车间调度问题。  相似文献   

6.
牛群  顾幸生 《医学教育探索》2006,(12):1472-1477
针对流水车间调度这一典型的NP难问题,采用了一种新型进化算法——DNA进化算法进行求解,并对算法做了改进。改进的DNA进化算法中引入了交换操作以更好地搜索解空间,并采用黄金分割率控制变异个体的数目。同时为了进一步提高搜索性能,采用一种新颖的启发式规则产生初始种群。以50个T aillard基准问题进行仿真,并与遗传算法进行了详细比较,仿真结果表明:改进的DNA进化算法具有更好的求解性能以及更高的运算效率。  相似文献   

7.
针对一类加工时间不确定的以总流经时间(TFT)为目标的置换Flow Shop调度问题,应用模糊数学的方法表示加工时间的不确定性,提出了一种改进的智能算法——异步遗传局部搜索算法(AGLA)。该算法初始种群的一个解由构造型启发式算法产生,其他解随机产生;通过引入一个加强的变邻域搜索机制和一个简单的交叉算子,对种群执行异步进化操作(AE);算法最后加入重启机制防止陷入局部极小。仿真实验结果验证了AGLA解决模糊Flow Shop问题的有效性。  相似文献   

8.
张海刚  顾幸生 《医学教育探索》2006,(12):1463-14671481
在建立一种物流配送车辆调度模型的基础上,针对传统启发式算法对复杂问题搜索效率低、易陷入局部最优的缺点,构造了DNA进化算法求解该问题。将其在个体变异操作中进行了一些改进,避免陷入局部最优。车辆调度问题(V SP)属于组合优化NP难题。采用V SP问题进行测试,仿真结果表明:该算法简单可行,与其他算法相比较,不但有很好的求解性能,而且具有更快的收敛能力与搜索能力。  相似文献   

9.
针对并行机调度问题的求解,提出一种新的混合量子衍生进化规划算法(Hybrid Quan-tum-Inspired Evolutionary Programming, HQEP)。目标函数是最小化所有工件的拖期总和。HQEP将量子进化算法中的量子位、线性叠加态和量子旋转门的概念引入到进化规划算法中。定义了新的用于调度问题的量子旋转角,使个体向更好的解靠近。此外,针对并行机问题本身,改进了个体的编码方式和新的变异方法。为了验证算法的有效性和收敛性,将HQEP算法应用于同等并行机调度拖期问题的求解并加以不同规模  相似文献   

10.
基于以最小完工时间为目标的带阻塞有差速混合流水车间调度问题,提出了一种改进的离散布谷鸟搜索算法。在基本布谷鸟搜索算法的莱维飞行和巢寄生性的基础结构上,提出了一种基于交叉策略的莱维飞行机制,以便算法能够解决离散问题;同时,通过非余弦递减策略的动态发现概率去发现劣质鸟巢,并利用排列差分进化算法的变异思想将劣质鸟巢重建;在搜索过程中设定全局最优极值保持代数为阈值去重新发现劣质鸟巢,以防止算法陷入局部最优;最后利用邻域搜索方法进一步提高算法的搜索精度。通过仿真实验验证了该算法在求解混合流水车间调度类离散问题上的有效性与优越性。  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
FOR anesthesiologis s ,treatingpostoperativepainhas alwaysbeen a problem.Althoughopioidshave been provedtobe effective,theirsideeffectscouldnotbeignored.With thedevelopmentofscienceand pharmacology,many drugs with aspectsof satisfactoryanalgesicefficacyand couldbe welltoleratedby patientshave been developed.And lornoxicamisone of them, which isa non-steroidalanti-inflammatorydrug (NSAID ), with analgesic, anti-infl-ammatory,andantipyreticproperties.Itseliminationhalf-time(3 to 5 hours) isle…  相似文献   

14.
Objective: To observe the therapeutic effects in acupunture treatment of primary dysmenorrhea combined with spinal Tui Na, and study its mechanism. Methods: Thirty cases of the treatment group were treated by acupuncture combined with spinal Tui Na, and thirty cases in the control group were treated by routine acupuncture. Results: The total effective rate was 93.3% in the treatment group, and 73.3% in the control group, with a significant difference between the two groups (P<0.05). Conclusions: Acupuncture combined with spinal Tui Na has good prospects for treatment of primary dysmenorrhea.  相似文献   

15.
In treating chronic nephropathy,Luo Lingjie,a chief physician,pays attention to regulating the balance between yin and yang,treating infection if present,and removing pathogenic factors.He prescribes gentle drugs and uses carefully strongly warming-tonifying ones,emphasizes the importance of persuading the patient to persist in treatment with medication and nurse one's health for recuperation,and is good at combined use of TCM and western medicine therapy and brings the merits of various therapies into full play,with obvious theraoeutic effects.  相似文献   

16.
Dr.Zhang Ren,the chief physician,is the chairman of Shanghai Acupuncture and Moxibustion Association.Having been engaged in medicine for about 40 years,he is experienced in treating various intractable diseases.In his long years of clinical practice,he advocates taking the TCM differentiation as the basis to seek for the acupuncture method for treatment of modern intractable diseases.The author of this essay had the fortune to follow Dr.Zhang in study.The following is a summary of Dr.Zhang's experience in the acupuncture treatment for different intractable diseases with the same therapeutic principle.  相似文献   

17.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

18.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

19.
20.
目的 探讨猪肺磷脂注射液联合经鼻持续气道正压通气(NCPAP)对呼吸衰竭早产儿的临床疗效及肌酸激酶同工酶活性(CK-MB)的影响.方法 选取呼吸衰竭早产儿80例,分为观察组和对照组各40例.对照组采用NCPAP给氧治疗,观察组给予NCPAP给氧联合猪肺磷脂气管内给药.观察两组患儿治疗前及治疗12h、24 h后PaO2、PaCO2、血氧饱和度(SaO2)、pH的变化情况,检测治疗前及治疗5d后血清CK-MB水平;评估两组患儿的临床治疗效果.结果 两组患儿PaO2、PaCO2、SaO2、pH比较,差异均有统计学意义(P<0.05),其中观察组治疗后的PaO2、SaO2、pH均高于对照组,PaCO2则低于对照组.两组的PaO2、SaO2、pH均随观察时间延长而升高(P<0.05),PaCO2均随观察时间的延长而降低(P<0.05).观察组治疗有效率为87.5%,显著高于对照组的70.0% (P <0.05).治疗5d后两组患儿血清CK-MB水平均较前降低(P<0.05),且观察组明显低于对照组(P<0.05).结论 猪肺磷脂注射液气管内给药联合NCPAP可以显著降低呼吸衰竭早产儿CK-MB的含量,提高治疗有效率,起到很好的呼吸循环支持作用.  相似文献   

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