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1.
CLIMATIC CHANGE SINCE LITTLE ICE AGE RECORDED BY DUNDE ICE CAP   总被引:21,自引:0,他引:21  
The climatic change since the Little Ice Age recorded in the Dunde Ice Cap is presentedin this paper. There have been three cold periods and three warm periods since 1400AD.Among them, the coldest one was in the 17th century. Many evidences verified the three coldand warm variations recorded in the Dundc Ice Cap. But it was found from the comparison between the Dunde Icc Cap climatic record and thewinter temperature record in Shanghai that there was a temporal dfference in climatic changebetween East China and West China. The general trend is that the cooling and warmingprocesses in West China were earlier than that in East China. In the Dunde Ice Cap, it isnow in an anomalous warm period, while it is not as warm as in Dunde Ice Cap recordaccording to the winter temperature in Shanghai. In addition to the possible cause of temporaldifference in climatic change between West China and East China, another possible cause isthat the greenhouse effect of CO_2 may already be recognizable in the Dunde Ice Cap a  相似文献   
2.
Autoverification is a process in which computer software will automatically evaluate laboratory test results, verify result integrity, and then release the results to the hospital interface without any technologist intervention. Autoverify release criteria are user defined and can be customized. The process of developing, implementing, and monitoring autoverify is achievable for most test results in laboratory medicine. The use of autoverification will improve result quality, increase revenue, and create faster turn-around times. All of this put together will ultimately lead to improved customer satisfaction. Computers and autoverification are survival tools in the competitive market of laboratory diagnostics services.Presented at the 8th Conference on Quality in the Spotlight, 17–18 March 2003, Antwerp, Belgium  相似文献   
3.
For a general renewal process N (allowing delay, defect and multiple simultaneous arrivals) the independence of the first renewal epochs of the marked processes got from N by Bernoulli 0/1 thinning is characterized. This independence is well-known to hold true in the case of homogeneous Poisson processes; by way of corollary one obtains the interesting observation that, when coupled with some minimal extra conditions, it in fact already identifies them. The proof is analytic in character.  相似文献   
4.
Let X1,X2,... be a sequence of i.i.d. random variables and let X(1),X(2),... be the associatedrecord value sequence. We focus on the asymptotic distributions of sums of records, Tn=∑nk=1X(k), forX1 ∈ LN(γ). In this case, we find that 2 is a strange point for parameter γ. When γ> 2, Tn is asymptoticallynormal, while for 2 >γ> 1, we prove that Tn cannot converge in distribution to any non-degenerate lawthrough common centralizing and normalizing and log Tn is asymptotically normal.  相似文献   
5.
Weak and strong functional limit theorems are obtained for record values and record epochs in a sequence of independent random variables with common distribution F. The emphasis is on the case in which F is concentrated on the non-negative integers. For contrast, the well-known case of continuous F is also considered. Analogues of results obtained earlier by Resnick, de Haan and the author for continuous F are presented here for F concentrated on the non-negative integers. Also is investigated under which circumstances the latter case is so close to the continuous F case that the resulting limit theorems are the same.  相似文献   
6.
Consider a multivariate mixture model where the random variables X 1, ..., X n given (1, ..., n ), are conditionally independent. Conditions are obtained under which different kinds of positive dependence hold among X i 's. The results obtained are applied to a variety of problems including the concomitants of order statistics and of record values; and to frailty models.  相似文献   
7.
本文估计序列|cm|1m{}的密集区域,其中{cm}是m型的.  相似文献   
8.
In this article, we introduce a novel Bayesian approach for linking multiple social networks in order to discover the same real world person having different accounts across networks. In particular, we develop a latent model that allows us to jointly characterize the network and linkage structures relying on both relational and profile data. In contrast to other existing approaches in the machine learning literature, our Bayesian implementation naturally provides uncertainty quantification via posterior probabilities for the linkage structure itself or any function of it. Our findings clearly suggest that our methodology can produce accurate point estimates of the linkage structure even in the absence of profile information, and also, in an identity resolution setting, our results confirm that including relational data into the matching process improves the linkage accuracy. We illustrate our methodology using real data from popular social networks such as Twitter , Facebook , and YouTube .  相似文献   
9.
卢全昌 《摩擦学学报》1993,13(4):356-363
本文研究了一种多变量在线测录仪,可用其在定向运转和反复正反变向运转的摩擦学试验中连续测量和记录试样的角速度、方位角、转数和摩擦距离等多个旋转变量的瞬时值,并且通过时间变量的关系,还可以清晰地显示出它们的变化过程和相互关系,基本能够描绘出试样在整个摩擦试验过程中的旋转动态。文章指出,利用这种测录仪还可得出一些间接的信息,如摩擦副的相对滑动量和试验过程中试样摩擦力的变化等。该仪器具有一机多用、所占空间  相似文献   
10.
This paper deals with the problem of predicting thesth record value based on the firstm record values (s>m) when the observations are from the exponential distribution. Various estimates for thesth record value are obtained and their mean square errors are compared.  相似文献   
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