Monotower平台在海上边际油气田开发中的应用前景

介绍了2006年4月英国北海南部区域Catter气田安装的世界上第一座靠风能和太阳能提供能量的创新型、环保型和节约型采油平台Monotower的结构型式、组成部分、特点和优点及应用现状，并结合目前国内海上边际油气田的开发现状、边际油气田开发技术创新前景、国际油价变化和能源的安全、有效供给、新能源的开发和利用、环境污染和气候变化等方面，对Monotower平台在边际油气田开发中的应用前景作了探讨。     

道路运输效率视角下的车道资源配置研究

对道路运输效率科学认识的缺乏,会导致设计理念的偏颇、道路资源配置的实际作用与其设计初衷的差异和交通问题的加剧。针对道路运输效率进行分析,认为合理减少出行时耗是提高道路运输效率的关键。在国内外干、支路车道资源配置,主、辅路车道资源配置,以及干、支路衔接模式的研究基础上,指出国内将提高通行能力和保障干路车速作为交通改善目的的逻辑性错误是导致路网结构失调,干、支路衔接不便的重要原因。最后,通过车道边际效用分析,以及干、支路,主、辅路车道资源增减对交通及城市功能的影响分析,得到车道资源合理配置的一般性方法。     

The maximum approximate composite marginal likelihood (MACML) estimation of multinomial probit-based unordered response choice models

The likelihood functions of multinomial probit (MNP)-based choice models entail the evaluation of analytically-intractable integrals. As a result, such models are usually estimated using maximum simulated likelihood (MSL) techniques. Unfortunately, for many practical situations, the computational cost to ensure good asymptotic MSL estimator properties can be prohibitive and practically infeasible as the number of dimensions of integration rises. In this paper, we introduce a maximum approximate composite marginal likelihood (MACML) estimation approach for MNP models that can be applied using simple optimization software for likelihood estimation. It also represents a conceptually and pedagogically simpler procedure relative to simulation techniques, and has the advantage of substantial computational time efficiency relative to the MSL approach. The paper provides a “blueprint” for the MACML estimation for a wide variety of MNP models.