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排序方式: 共有976条查询结果,搜索用时 15 毫秒
61.
建立了一类新的差分不等式,利用差分定义、求和技巧、差分方程比较原理,给出了不等式中未知函数的估计,推广了已有的结果. 相似文献
62.
以金融时间序列中同积向量的充分改进为对象,分析充分改进的最小二乘估计。在统计量的极限分布非标准时,构造充分改进的最小二乘估计。研究表明,改进的最小二乘估计方法是一种非参数方法,有助于充分的最小二乘估计。 相似文献
63.
余思勤 《上海海事大学学报》1995,(4)
讨论了抽样调查在港口吞吐量调查中的应用前景,分析了港口吞吐量抽样调查方案设计的各个环节,包括:方案设计的原则、技术方法、抽样公式、调查时间、分层确定、季节变动处理和非抽样误差控制等。 相似文献
64.
林昭绒 《武汉体育学院学报》2001,35(6):86-88
论述了指导发现式教学模式在健美操课中的运用程序与实现环境等原理,并在其对健美操中的运用进行了分析. 相似文献
65.
66.
Demand for and productivity analysis of Turkish public theater 总被引:1,自引:0,他引:1
We estimate a demand function for live theater provided by the General Directorate of State Theaters in Turkey. We show that demand is more elastic in less developed cities, that attendance is not significantly affected by various qualitative variables, and that the government's practice of offering free passes to government officials is an ineffective way of increasing paid attendance. Comedies and musicals both show significantly higher attendance. Having a Turkish author does not significantly affect attendance. Having a known author significantly increases attendance for more developed cities but not for less developed cities. Being the opening season significantly reduces attendance in less developed cities but has no effect in more developed cities. We also present evidence of inefficiency in state theaters in Turkey through a performance of plays equation in which we evaluate the determinants of the number of performances per play. 相似文献
67.
为了使桥式起重机的寿命管理措施更切合实际,必须提高桥机的强度和刚度测试的精度。文中提出了现场测试中可以采用的一些提高精度的措施和方法。 相似文献
68.
根据收集到的某航运公司4318只自备和长期租用的冷藏集装箱在4年多时间内的现场故障数据,采用截尾寿命数据分析的技术,求解了当部分样本失效时,母体的参数估计值和冷藏集装箱制冷装置的主要部件如压缩机、膨胀阀以及蒸发器的可靠性概率密度函数等可靠性特征值。文章还讨论和考察了Daikin,PaulKlinge,Mitsubishi和Carrier4种主要集装箱制冷装置的可靠性特性。 相似文献
69.
粒子群优化算法具有全局性能好、搜索效率高、容易实现等优点.文章在极大似然估计模型的基础上,采用粒子群优化算法,提出一种基于实例的边坡安全系数估计模型.工程实例研究表明,该模型精度明显优于传统极大似然估计模型和遗传算法优化模型,说明本文方法是科学可行性的. 相似文献
70.
Shanmugasundaram Kumaravel 《Indian journal of clinical biochemistry : IJCB》2012,27(4):422-425
Criterion for patient selection and demographic comparison between the two groups, the numbers in individual groups (normal union or defective union) how the observers were blinded for the samples and control group measurements in the graphs were not mentioned. No data on actual measurement levels is given. No where it is mentioned like it is an average of all normal union or defective union in tables or diagrams. The treatment methodology maybe still focused including either conservative or surgical treatment since a displaced fracture cannot be compared with an osteotomy. The cases shall be followed up for a longer period. Some suggestions on how to blind the observers is given. In the one year period there was neither mention of the failure of treatment or complications of any of neither these 36 cases nor any drop out for follow-ups. There was also no mention of any case which initially put on conservation was changed to surgical management. The authors could have one group of patients taking this food stuff and another group who refused this food stuff. The statistical test used to compare the levels of factor is not mentioned. Mere statement that ‘p’ values were significant will not benefit the reader. Failure to produce X-rays even for a single case weakens the study. X-rays are needed to confirm the diagnosis of a fracture and confirm the position of implants and fracture fragments. The remaining period after confirming the fracture/implant position the case shall be followed only with marker estimation. Once the desired levels of increase or tapering of marker level achieved then X-rays can be taken to correlate with clinical findings and radiology. Union as one group and the second group shall be called as non-union or delayed union. The second group (the poor callus group) is mentioned as malunion possibly by over-sight. Probably they were meaning the non union or delayed union group or defective union as malunion. This should be preferably be written non union or delayed union. Malunion means the fracture actually unites and union process is completed. In a group of fractures (hypertrophic non unions) the callus formation is excessive, still the fracture is ununited. Thus the enzyme or markers alone cannot disclose the details of the completion of union they can herald bone formation. 相似文献