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141.
利用SPSS Clementine 10.1数据挖掘工具,遵循CRISP-DM模型的商业目标、数据理解、建立模型的流程对超市顾客进行分析研究。提出衡量超市客户忠诚度的忠诚度系数指标,建立忠诚度—盈利性顾客细分模型,运用k-means算法对超市顾客进行聚类分析,帮助超市企业准确识别不同类型的顾客群,尤其是忠诚的高盈利顾客。再利用所建立的序列分析模型分析顾客类别变化路径,预测顾客价值变化趋势,及早发现潜在价值顾客,使其尽早成为企业忠诚的高价值顾客,实现超市企业利润的有效提升,最终在日益激烈的商业竞争中立于不败之地。  相似文献   
142.
城市震害时空序列的展开过程分析   总被引:1,自引:0,他引:1  
本文系统地介绍城市地震灾害的主体,震害的特征及按时间、空间序列的发展过程。城市震害是多种灾害同时发生、相互影响,并且多种灾害在时空序列上都有发生、发展和延续的过程。通过对以往几次城市地震灾害的现象的研究、展示其在时空序列的分布规律,力求找到各种灾害与抗震救灾活动的对应关系  相似文献   
143.
We report the diagnosis of amnion rupture sequence made by sonography and fetoscopy during the first trimester of gestation in a case of missed abortion. The investigation revealed a demised fetus with the characteristics of 9 weeks of development. The early fetus had an amnion adhesion at the tip of the nose and strands of amnion wrapped around the terminal phalanges of both feet. No defects in addition to the face and limb involvement were identified. The karyotype was normal: 46,XX. In the reported case, fetoscopy allowed confirmation of the sonographic diagnosis of an amnion rupture sequence in the first trimester of gestation and consequently helped to clarify the cause of abortion in this case of early fetal demise. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
144.
Sulfide dioxide(SO2) is often released during the combustion processes of fossil fuels. An integrated bioreactor with two sections, namely, a suspended zone(SZ) and immobilized zone(IZ), was applied to treat SO2 for 6 months. Sampling ports were set in both sections to investigate the performance and microbial characteristics of the integrated bioreactor. SO2 was effectively removed by the synergistic effect of the SZ and IZ, and more than 85%removal efficiency was achieved at steady state. The average elimination capacity of SO2 in the bioreactor was 2.80 g/(m3·hr) for the SZ and 1.50 g/(m3· hr) for the IZ. Most SO2 was eliminated in the SZ. The liquid level of the SZ and the water content ratio of the packing material in the IZ affected SO2 removal efficiency. The SZ served a key function not only in SO2 elimination, but also in moisture maintenance for the IZ. The desired water content in IZ could be feasibly maintained without any additional pre-humidification facilities. Clone libraries of 16 S r DNA directly amplified from the DNA of each sample were constructed and sequenced to analyze the community composition and diversity in the individual zones.The desulfurization bacteria dominated both zones. Paenibacillus sp. was present in both zones, whereas Ralstonia sp. existed only in the SZ. The transfer of SO2 to the SZ involved dissolution in the nutrient solution and biodegradation by the sulfur-oxidizing bacteria.This work presents a potential biological treatment method for waste gases containing hydrophilic compounds.  相似文献   
145.
农田溪流人工深潭地貌格局暂态存储特征分析   总被引:2,自引:0,他引:2  
李如忠  黄青飞  钱靖  殷晓曦  韦林 《环境科学》2016,37(8):2964-2972
2015年11月~2016年2月,以NaCl为示踪剂,在巢湖流域某一农田源头溪流开展了5次野外示踪试验,并据此计算溪流的物理特征参数和暂态存储指标;通过对深潭渠段与平直渠段相关指标的比较,解析人工深潭地貌格局的暂态存储特征.结果表明:1人工深潭地貌格局渠段A_s/A基本都较平直渠段更高,但其交换系数α却较平直渠段低一个数量级;2人工深潭地貌格局的暂态存储对于溶质滞留的影响较平直渠段大,但其流动水体的溶质滞留能力则较平直渠段弱;3尽管深潭地貌格局拥有相对较大的A_s/A比值,但对溶质运移转化的综合影响却低于平直渠段;4人工深潭的暂态存储指标F200med可以解释18.86%~26.05%的溶质行进时间,平直渠段可以解释5.28%~33.87%,且大部分情况下平直渠段都较深潭渠段更高;5深潭地貌格局与平直渠段在φ_w、φ_A和T_s方面差异明显,而在其他指标方面则区别不显著.  相似文献   
146.
The application of sequential extraction procedures to determine metal speciation in sediments is fraught with uncertainty regarding what is actually dissolving or re-precipitating at each stage. In order to choose an appropriate scheme for the investigation of contaminated anaerobic mud two different sequential extraction procedures (Kersten and Förstner, 1986; Quevauviller, 1998) were investigated using a Cryogenic SEM (CryoSEM) technique coupled with energy dispersive X-ray analysis (EDXA). This enabled assessment of the degree of reagent selectivity and any re-precipitation associated with the respective methods. Analysis of the non-leached sediment revealed the most abundant authigenic minerals in order of decreasing abundance to be Fe2+-phosphate vivianite (Fe3(PO4)2·8H2O), mixed Fe, Zn, Cu sulphides, pyrite and calcite. After each stage of the sequential extraction the sediment residue was examined using CryoSEM. After extraction of the exchangeable fraction no obvious evidence of mineral dissolution was observed. Calcite was not completely dissolved during the carbonate extraction stage of either procedure. Vivianite began to dissolve in the carbonate extraction stage of both procedures and was completely dissolved by oxide extraction stage of both procedures. The sediment leached by acidified ammonium oxalate, contained abundant Fe oxalate crystals, suggesting that a large proportion of the Fe released from the vivianite has been re-precipitated. The Fe oxalate was then dissolved with the subsequent sulphide fraction. The technique used to extract the sulphide and organic fraction is the same in both schemes and no sulphide or metal rich organic matter was found in either residue.  相似文献   
147.
江西九江“11.26”地震应急   总被引:1,自引:0,他引:1  
  相似文献   
148.
Stickler syndrome or hereditary progressive arthro-ophthalmopathy, is an autosomal dominant condition characterized by ocular manifestations, arthritic changes, orofacial features and deafness, in variable degrees. We report the first case of prenatal diagnosis of Stickler syndrome in a child with a Pierre–Robin sequence (PRS) causing a polyhydramnios. When isolated polyhydramnios is not explained by immunological, metabolic or infectious causes, swallowing difficulty due to PRS must be considered. As PRS is aetiologically heterogenous, the prognosis depends on the cause. Genetic investigations and familial history must be taken into account. Here, in a context of familial Stickler syndrome, making the prenatal diagnosis of PRS as part of Stickler syndrome allowed us to reassure the parents and to anticipate airway trouble at the child's birth. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
149.
150.
本文介绍了江西省九江"11·26"5.7级破坏性地震基本情况,对少震弱震地区发生破坏性地震后如何应对进行了分析,从加强地震序列跟踪监测,地震台站在新时期为政府、为社会服务,发挥其应有的作用三个方面提出了应对破坏性地震的对策.  相似文献   
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