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1.
四川盆地卤水分布广泛,资源丰富, 早为世人所瞩目,中三叠统雷口坡组是四川盆地最早开采天然气和盐卤的层系之一。根据盆地雷口坡组大量钻井资料研究表明,盆地雷口坡组主要成盐期分别为雷三2 期和雷四2 期,在盆地东部和南部由于受到古隆起的影响,盐岩地层已被剥蚀难以保存,现今盐岩主要分布在开江古隆起和泸州古隆起的西部以及天井山古隆起的南部(华蓥山以西—龙门山以东的川西—川中地区)。印支运动对盆地雷口坡组盐岩在平面的迁移起着十分重要的作用,根据不同时期盐岩统计数据看,两期盐盆在平面上具有向西迁移、叠加的特征,其中川中的GS1 井就钻遇了这两期的盐岩。  相似文献   
2.
1938年夏天,美国年轻学者科尼利尔斯·奥斯古德为了履行与燕京大学的合作计划,不远万里来到滇池西岸一个名不见经传的小村庄调查.1961年,他开启尘封的笔记本,整理旧资料,补充新文献,完成了<旧中国的农村生活:对云南高峣的社区研究>.70年过去,重温科尼利尔斯·奥斯古德的研究历程,我们仍会从中获得许多有益的启示.  相似文献   
3.
Approximation formulae are developed for the bias of ordinary and generalized Least Squares Dummy Variable (LSDV) estimators in dynamic panel data models. Results from Kiviet [Kiviet, J. F. (1995), on bias, inconsistency, and efficiency of various estimators in dynamic panel data models, J. Econometrics68:53-78; Kiviet, J. F. (1999), Expectations of expansions for estimators in a dynamic panel data model: some results for weakly exogenous regressors, In: Hsiao, C., Lahiri, K., Lee, L-F., Pesaran, M. H., eds., Analysis of Panels and Limited Dependent Variables, Cambridge: Cambridge University Press, pp. 199-225] are extended to higher-order dynamic panel data models with general covariance structure. The focus is on estimation of both short- and long-run coefficients. The results show that proper modelling of the disturbance covariance structure is indispensable. The bias approximations are used to construct bias corrected estimators which are then applied to quarterly data from 14 European Union countries. Money demand functions for M1, M2 and M3 are estimated for the EU area as a whole for the period 1991: I-1995: IV. Significant spillovers between countries are found reflecting the dependence of domestic money demand on foreign developments. The empirical results show that in general plausible long-run effects are obtained by the bias corrected estimators. Moreover, finite sample bias, although of moderate magnitude, is present underlining the importance of more refined estimation techniques. Also the efficiency gains by exploiting the heteroscedasticity and cross-correlation patterns between countries are sometimes considerable.  相似文献   
4.
马克思与后现代主义都对传统主体概念进行了颠覆。在马克思那里 ,主体不再指自我意识或自我 ,而是渗透了历史性原则 ,是创造和规定人及产物的历史过程 ;其客观上表现为一定的社会关系和社会形态 ,主观上表现为人的社会历史存在。而后现代主义则反对主客二分 ,反对人类中心主义 ,反对寻求同一性 ,反对普遍主义 ,把以认识主体为核心的反映论作为批判的目标。这是两种不同的颠覆方式 ,但都宣判了传统主体概念的死亡。  相似文献   
5.
In this paper, we deal with a discrete-time multiserver retrial queue with finite population. Firstly, we study the Markov chain at the epochs immediately after slot boundaries making emphasis on the computation of its steady-state distribution. Then, the main performance measures are investigated. Besides, we simulate the waiting time of a customer in the retrial group under three different queueing policies. Some numerical examples are given to illustrate the analysis.  相似文献   
6.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations.  相似文献   
7.
Summary We consider a lotL formed byN apparently similar unitsW 1,…,W N, where each of theW i may come from one of two different populationsP 1 andP 2;T 1,…,T N denote the corresponding lifetimes. The units fromP i undergo a failure of kindi and their survival function isS i (t). We assume that the failure rate function are known and that the units fromP 1 are ?substandard?: λ 1 (t)≥λ 2 (t), ∀t≥0. We want to putW 1,…,W N under a pre-operational test (burn-in test) in order to eliminate at least a great part of the substandard units and we face the problem of obtaining a rule for stopping the test under the assumption that, with the failure of a unit, it is possible to recognize the population from which the unit comes. Such a problem will be formalized as an optimal stopping problem for a suitably defined Markov process. Our study shall evidentiate some fundamental aspects of the problem and the role of the prior distribution of the (random) numberM 0 of those units inL coming fromP 1 (substandard). The latter distribution has a great influence on the form of the solution. This research was supported by the C.N.R. Project ?Statistica Bayesiana e Simulazione in Affidalità e Modellistica Biologica?.  相似文献   
8.
Federal legislation regarding health care in the U.S. has increased rapidly in the past few years. A major law with potential far-reaching effects was enacted as a result of increasing legislation and rising health care costs. This law,The National Health Planning and Resources Development Act,has created a network of over 200 local, mostly nongovernment units, called health systems agencies. These agencies are responsible for areawide health planning, plan implementation, review and approval of federal health care expenditures for local programs, and facilities review. They will affect health and mental health programs at the local level. The article is directed to local health and mental health care providers who will, of necessity, deal directly with the local HSA's.  相似文献   
9.
程代伟 《科学咨询》2003,(17):27-27
准确的基础资料是系统运行的前提.在ERP系统的使用中,基础资料一定要保证正确性、完整性和唯一性.BOM是系统最重要的基础资料之一,它的准确与否将直接影响MRP计划、生产投料、生产领料、成本计算等业务的正确性.为准确录入BOM的基础数据,在长期工作实践中,本人摸索出一些技巧,不敢私自独用,便拿出来与大家分享.  相似文献   
10.
从理论语言学史看,伦敦学派经历了从马林诺夫斯基人类语言学到弗斯语境语言学,再到韩礼德系统功能语言学的发展。后现代哲学使哲学的终极性基础,亦即使认识主客观对象的途径和方法得到根本的转换(转换成符号),是西方哲学中最重要的思想事件,即所谓"语言学转向",我们无妨说,韩礼德80年代后对他的系统功能语言学的推进,是以符号中介论为其深层理论背景的,或者说与"语言学转向"是一致的。  相似文献   
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