修正衰减曲线法在低渗气藏动态分析中的应用

摘要：压力是气井和气藏生产动态分析的灵魂，很多动态分析方法都与压力有着直接的联系。然而，由于致密低渗透气藏产量低、压力下降快、关井压力恢复缓慢等生产特征，以及生产方式的限制，在生产过程中很难获得气井或气藏地层压力资料。压降法、产量不稳定分析法和产量递减曲线分析方法是气藏常用的气井生产动态分析方法，但由于地层压力资料缺乏，压降法和产量不稳定分析法也都受到了很大的限制，在衰减递减曲线分析方法的基础上对其进行修正，摆脱了压力资料的限制，通过和压降法对比分析，验证了修正衰减曲线分析方法在生产动态分析中的可靠性。     

The Complete Exact Null Distribution of Spearman's Rho for n = 12(1)18

Spearman's rank correlation coefficient, Rho, is a widely used nonparametric measure of association. Complete, exact tables of the null distribution are calculated and presented for n = 12 to 18.     

大型体育场馆低碳规划策略研究——以第七届农运会为例

大型体育场馆投资金额大、管理复杂，早期规划直接影响后期经济效益，同时片面追求设计和形体美，使得体育场馆能耗严重，这与国家提倡的低碳建筑可持续发展观是背道而驰。文章以第七届农运会体育场馆为例，在充分分析农运会体育场馆建设及其特点的基础上，提出合理规划管理第七届农运会大型体育场馆的建设对策性建议，使之更好的为本国的体育发展服务。     

Asymptotic theory for maximum likelihood estimates in reduced-rank multivariate generalized linear models

Reduced-rank regression is a dimensionality reduction method with many applications. The asymptotic theory for reduced rank estimators of parameter matrices in multivariate linear models has been studied extensively. In contrast, few theoretical results are available for reduced-rank multivariate generalized linear models. We develop M-estimation theory for concave criterion functions that are maximized over parameter spaces that are neither convex nor closed. These results are used to derive the consistency and asymptotic distribution of maximum likelihood estimators in reduced-rank multivariate generalized linear models, when the response and predictor vectors have a joint distribution. We illustrate our results in a real data classification problem with binary covariates.     

The aligned rank transform and discrete variables: A warning

For two-way layouts in a between subjects ANOVA design the aligned rank transform (ART) is compared with the parametric F-test as well as six other nonparametric methods: rank transform (RT), inverse normal transform (INT), a combination of ART and INT, Puri & Sen's L statistic, van der Waerden and Akritas & Brunners ATS. The type I error rates are computed for the uniform and the exponential distributions, both as continuous and in several variations as discrete distribution. The computations had been performed for balanced and unbalanced designs as well as for several effect models. The aim of this study is to analyze the impact of discrete distributions on the error rate. And it is shown that this scaling impact is restricted to the ART- as well as the combination of ART- and INT-method. There are two effects: first with increasing cell counts their error rates rise beyond any acceptable limit up to 20 percent and more. And secondly their rates rise when the number of distinct values of the dependent variable decreases. This behavior is more severe for underlying exponential distributions than for uniform distributions. Therefore there is a recommendation not to apply the ART if the mean cell frequencies exceed 10.     

竞争市场中生产与碳交易策略

在碳排放约束下,利用动态古诺模型,分析厂商如何优化产量、交易碳排放权的规模、净化节约额以实现利润最大化的问题,得到相应的均衡量和各阶段最优量,并给出竞争市场中的企业减排策略以及政府的行为和碳排放权价格对企业减排策略的影响,阐述在竞争市场中减排和碳排放权交易的运行机制。研究发现: 双寡头竞争市场中存在均衡状态;在减排率较低时,制造上获得最高利润,而企业追求过高的减排率将会导致过分依赖碳减排市场而获得较低的利润;制造商应该适时低价购入过量碳排放权,而在高价时卖出多余的碳排放权,以充分利用碳排放权市场以增加利润降低成本;制造商的利润会随着政府碳排放权分配系数的增加而增加。     

Group sequential monitoring based on the weighted log‐rank test statistic with the Fleming–Harrington class of weights in cancer vaccine studies

In recent years, immunological science has evolved, and cancer vaccines are now approved and available for treating existing cancers. Because cancer vaccines require time to elicit an immune response, a delayed treatment effect is expected and is actually observed in drug approval studies. Accordingly, we propose the evaluation of survival endpoints by weighted log‐rank tests with the Fleming–Harrington class of weights. We consider group sequential monitoring, which allows early efficacy stopping, and determine a semiparametric information fraction for the Fleming–Harrington family of weights, which is necessary for the error spending function. Moreover, we give a flexible survival model in cancer vaccine studies that considers not only the delayed treatment effect but also the long‐term survivors. In a Monte Carlo simulation study, we illustrate that when the primary analysis is a weighted log‐rank test emphasizing the late differences, the proposed information fraction can be a useful alternative to the surrogate information fraction, which is proportional to the number of events. Copyright © 2016 John Wiley & Sons, Ltd.     

Robust Smoothed Rank Estimation Methods for Accelerated Failure Time Model Allowing Clusters

Smoothed Gehan rank estimation methods are widely used in accelerated failure time (AFT) models with/without clusters. However, most methods are sensitive to outliers in the covariates. In order to solve this problem, we propose robust approaches based on the smoothed Gehan rank estimation methods for the AFT model, allowing for clusters by employing two different weight functions. Simulation studies show that the proposed methods outperform existing smoothed rank estimation methods regarding their biases and standard deviations when there are outliers in the covariates. The proposed methods are also applied to a real dataset from the “Major cardiovascular interventions” study.     

大城市低收入老人群体状况分析

本文依据在广州的调查数据 ,揭示了低收入老人的群体特征 ,提出制订老龄政策时 ,适当照顾低收入老人 ,同时动员家庭、单位和社会都来积极关心这部分脆弱群体