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131.
132.
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
133.
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
134.
参数假设检验中存在四对密切相关的概念:原假设与备择假设、两类错误、P-值法与临界值法、区间估计与假设检验,深入了解这些概念及其原理之间的关系有利于准确把握假设检验的思想与方法。 相似文献
135.
以排队论理论为基础,建立了医院眼科病人排队系统的数学模型.首先,建立了对医院病床安排系统进行综合评价的指标体系,并对现有FCFS规则扣改进规则进行了评价;然后,建立了区间估计模型,使得病人在门诊时就被告知大致入住时间.最后,建立了多指标床位分配模型,得出了床位的最佳设置值. 相似文献
136.
随着可计算一般均衡模型(CGE)在经济政策领域中的广泛应用,可计算一般均衡模型所需要的基础研究——对资本存量和可计算总量生产函数的估计就成为必不可少的一个环节。通过估计中国资本存量,用计量分析的方法拟合出CGE计算所需的中国总量生产函数。 相似文献
137.
文章从随机变量k-阶矩的定义出发,结合已有的定理推导出一些不等式,进而说明一些相关随机变量k-阶矩存在的条件。 相似文献
138.
通过文献资料法、归纳演绎法对分级教学过程中的分级标准及评价体系进行分析,旨在对高校体育课的分级教学提供有益参考. 相似文献
139.
Temporal variation of dynamical modal properties of a base-isolated building is investigated using earthquake records in the building. A batch processing least-squares estimation method is applied to segment-wise time-series data. To construct an input-output system, an auto-regressive model with exogenous input (ARX) of second-order including a forgetting coefficient as a weighting coefficient is used for the estimation of modal parameters. The fundamental and second natural frequencies and the damping ratios of the fundamental and second natural modes of the base-isolated building are identified in the time domain. The identified results are consistent with the results obtained from the micro-tremor vibration data, forced-vibration test data and earthquake records in the present base-isolated building in the case of taking into account the amplitude-dependency of the iso- lators and viscous dampers. It is finally pointed out that several factors, e.g., amplitude dependency of the isolator and damper system and special characteristics of the series-type viscous damper system, may be related complicatedly with the temporal variation in modal properties of the above-mentioned system. 相似文献
140.
在指数分布参数的先验分布为其共轭先验分布时,给出了其在熵损失函数下的-估计公式,并给出了容许估计的一般形式. 相似文献