Household energy consumption versus income and relative standard of living: A panel approach

Our fundamental premise is that energy consumption at the household level is a key indicator of standard of living. We employ state-of-the-art panel cointegration techniques to evaluate the nature of the relationship between income measures and energy consumption measures for seven East Indian Ocean countries. The general finding is that income and household electricity consumption are not cointegrated. Given this finding, we conclude that standard of living measures that rely on income measures and do not include household-level energy consumption information will necessarily miss important indications of both levels and changes of standard of living.     

稳定同位素井间示踪技术在深层块状稠油油藏水驱特征研究的应用

经对冷43块深层块状普通稠油水驱注水5个试验井组开展的稳定同位素示踪测试，利用中子活化技术分析样品，采用先进的示踪剂定量分析与流动模拟相互结合的方法，以示踪数值模拟为手段，评价了油井连通、油层平面及纵向上的非均质性、隔层的封隔性等因素对水驱控制程度及动用状况的影响，通过优化注水推进方向及速度，强化动态调整措施，提高了稳产基础。     

Differential Action of Connexin Hemichannel and Pannexin Channel Therapeutics for Potential Treatment of Retinal Diseases

Dysregulation of retinal function in the early stages of light-induced retinal degeneration involves pannexins and connexins. These two types of proteins may contribute to channels that release ATP, leading to activation of the inflammasome pathway, spread of inflammation and retinal dysfunction. However, the effect of pannexin channel block alone or block of both pannexin channels and connexin hemichannels in parallel on retinal activity in vivo is unknown. In this study, the pannexin channel blocker probenecid and the connexin hemichannel blocker tonabersat were used in the light-damaged rat retina. Retinal function was evaluated using electroretinography (ERG), retinal structure was analyzed using optical coherence tomography (OCT) imaging and the tissue response to light-induced injury was assessed immunohistochemically with antibodies against glial fibrillary acidic protein (GFAP), Ionized calcium binding adaptor molecule 1 (Iba-1) and Connexin43 (Cx43). Probenecid did not further enhance the therapeutic effect of connexin hemichannel block in this model, but on its own improved activity of certain inner retina neurons. The therapeutic benefit of blocking connexin hemichannels was further evaluated by comparing these data against results from our previously published studies that also used the light-damaged rat retina model. The analysis showed that treatment with tonabersat alone was better than probenecid alone at restoring retinal function in the light-damaged retina model. The results assist in the interpretation of the differential action of connexin hemichannel and pannexin channel therapeutics for potential treatment of retinal diseases.     

Temporal aggregation and spurious instantaneous causality in multiple time series models

Large aggregation interval asymptotics are used to investigate the relation between Granger causality in disaggregated vector autoregressions (VARs) and associated contemporaneous correlation among innovations of the aggregated system. One of our main contributions is that we outline various conditions under which the informational content of error covariance matrices yields insight into the causal structure of the VAR. Monte Carlo results suggest that our asymptotic findings are applicable even when the aggregation interval is small, as long as the time series are not characterized by high levels of persistence.     

WE54镁合金中析出相的特点

WE54(Mg-5.4Y-2.3Nd-1.6Gd-0.5Zr)镁合金试样在铸态、T4和T6状态下,呈现出不同的显微组织形貌特征和微区化学成分,而且力学性能也随着处理工艺的不同而发生变化。采用金相显微镜、大功率X射线衍射仪、高分辨场发射扫描电镜及能谱仪分析研究了WE54合金的微观组织形貌、析出相以及微区化学成分的变化。结果表明,WE54合金在铸造状态下,Mg12Nd和Mg24Y5两种新相沿着晶界析出,呈现出网状结构,稀土Gd完全固溶在基体之中,在晶内和晶界析出物的微区化学成分分析中没有发现Gd;经过固溶处理后,铸态时沿晶界分布的大块析出物几乎全部固溶于基体Mg之中,力学性能有所提高;经过人工时效后,晶内析出大量细小的新相。经过对比试样沿横向和纵向析出相的特点,确定该析出相为片状结构。析出相沿3个方向排列分布,而且3个方向之间夹角互成120°,呈现出严格的位向关系,合金的强度进一步得到提高,但伸长率有所降低。     

挤压铸造ZA43合金组织及性能研究

研究了挤压铸造对ＺＡ４３合金组织性能的影响，分析了高压下凝固ＺＡ４３合金的组织形成过程。结果表明：挤压铸造可细化合金的铸态组织、减轻枝晶偏析，大幅度提高其力学性能；枝晶闸显微缩孔的消除是合金韧性显著改善的首要原因。     

State feedback control of continuous-time T-S fuzzy systems via switched fuzzy controllers

This paper studies the problem of state feedback control of continuous-time T-S fuzzy systems. Switched fuzzy controllers are exploited in the control design, which are switched based on the values of membership functions, and the control scheme is an extension of the parallel distributed compensation (PDC) scheme. Sufficient conditions for designing switched state feedback controllers are obtained with meeting an H_∞ norm bound requirement and quadratic D stability constraints. It is shown that the new control design method provides less conservative results than the corresponding ones via the parallel distributed compensation (PDC) scheme. A numerical example is given to illustrate the effectiveness of the proposed method.     

基于遗传神经网络的超混沌时间序列预测

研究了超混沌系统的预测问题。通过分析混沌时间序列,建立具有多个隐节点的3层前馈网络,基于泛化性考虑采用剪枝算法训练,在保证预测精度的基础上消去部分隐节点以降低网络复杂性,利用遗传算法具有的全局寻优能力重新训练网络,利用具有局部寻优能力BP算法再次训练该网络。对Mackey-Glass时滞混沌系统预测实验结果表明,改进算法的泛化性能优于经典BP网络,归一化预测精度提高10倍多,能够较好地解决超混沌系统的预测问题。     

Robust model selection with flexible trimming

The forward search provides data-driven flexible trimming of a C_p statistic for the choice of regression models that reveals the effect of outliers on model selection. An informed robust model choice follows. Even in small samples, the statistic has a null distribution indistinguishable from an F distribution. Limits on acceptable values of the C_p statistic follow. Two examples of widely differing size are discussed. A powerful graphical tool is the generalized candlestick plot, which summarizes the information on all forward searches and on the choice of models. A comparison is made with the use of M-estimation in robust model choice.     

Global existence and nonexistence for degenerate parabolic equations with nonlinear boundary flux

In this paper, by constructing various kinds of sub- and super-solutions and using the basic properties of M-matrix, we give the necessary and sufficient conditions of global existence for nonnegative solutions to a degenerate parabolic system with completely coupled boundary conditions, which generalize the recent results of, for instance, Cui [Z. Cui, Critical curves of the non-Newtonian polytropic filtration equations coupled with nonlinear boundary conditions, Nonlinear Anal. 68 (2008) 3201–3208], Zhou–Mu [J. Zhou, C. Mu, Algebraic criteria for global existence or blow-up for a boundary coupled system of nonlinear diffusion equations, Appl. Anal. 86 (2007) 1185–1197] etc.