Income, Time Effects and Direct Preferences in a Multimodal Choice Context: Application of Mixed RP/SP Models with Non-Linear Utilities

Transport problems typically involve at least two types of constraints, on income and on time. Therefore, the indirect utility function depends either on the income available after having subtracted the cost of the discrete alternative and on the free time left after having worked and travelled by each competing option. In the typical linear-in-the-attributes and in-the-parameters specification, that represents the first grade approximation of the indirect utility function, the effect of income and time constraints cancel out and only the cost and time of the alternatives matter in the comparison between them. From a microeconomic point of view this is equivalent to assume that income and time effects could be disregarded; which is not always the case. To account for these effects the utility function should include second order attributes; however, in non-linear utility functions it may not be easy to distinguish among several effects that could be relevant: direct preferences for good and leisure, and simple interactions between attributes other than income and time effects. This paper analyses these effects from a theoretical point of view focusing on the possible confounding problem in detecting income and time effects. We use a dataset collected for a modal choice context and containing both revealed and stated preference data, and estimate several NL models examining the effect of the different second-order terms on detecting income and time effects. We compared specifications including square cost and time attributes, interactions between time and cost, cost divided by the income available to be spent on free time, and time multiplied by free time. Our results confirm the strong effect of direct preferences for goods and leisure time on choice, and the potential confounding effect between quadratic attributes and other non-linear omitted terms. Finally, we also found that care should be taken in highlighting income and time effects using mixed data sources, since confounding effects can occur when non-linearities are accounted for in both data sets.     

二元复合驱阶段见效特征

针对孤东油田油藏条件，通过室内试验研究，确定了以胜利石油磺酸盐为活性剂主剂和聚合物的二元复合驱油体系，通过两者之间的协同效应，增加水驱波及体积和洗油效率。该体系在孤东油田七区西馆上54—61层进行试验，取得了较好的阶段性降水增油效果。本文分析了复合驱见效特征和影响见效因素，为下步跟踪分析调整具有指导意义。     

拟声波构建技术在砂泥岩薄互层储层预测中的应用

拟声波构建技术依据对储层敏感的非声波地球物理测井信息构建具有声波量纲的新曲线，进而形成拟声波曲线。由于该声波曲线既能反映地层速度和波阻抗的变化，又能反映地层岩性的细微差别，可以较好地解决薄互层储层定量预测中的岩性识别、薄层分辨等难题。针对歧口凹陷南大港地区地层实测声波时差曲线对砂、泥岩的岩性反映不明显，无法进行储层反演预测的问题，采用了拟声波构建技术。将对储层岩性敏感性好的自然电位曲线转换成拟声波曲线，以此为约束条件实现了储层预测的目的，取得了较好的应用效果。     

矿物质催化合成SP及SP-C

探索出一种以矿物质（橡胶填充剂）为催化剂合成ＳＰ及ＳＰ－Ｃ的新工艺。选择了最佳的工艺条件。此法制成的ＳＰ及ＳＰ－Ｃ产品性能优良、质量稳定。     

成品催化剂间歇控制系统设计和实现

以某石化公司新建的一条通用催化剂生产线为背景,介绍间歇过程设计需要遵守的SP88标准和此间歇控制系统的软硬件配置.深入分析TPB(Total Plant Batch)软件功能体系,给出能完成多种成品催化剂制备要求的一个间歇过程控制系统设计和实现方法,并在实际中得到了成功应用.     

不同尺寸段塞组合等流度二元驱驱油效果评价

辽河油田锦16块实施二元复合驱以来,仍存在部分注入井单层吸液量过大,使注入液在各层中的推进速度不一致,从而导致相应的采油井聚合物质量浓度上升较快的问题。通过室内驱替实验,采用均质岩心和非均质岩心,对比不同段塞组合的等流度二元驱驱油方法在非均质岩心上的驱油效果。结果表明,在相同聚合物用量和总注入孔隙体积倍数条件下,在三层非均质岩心上等流度驱油方法比常规单段塞驱油方法化学驱采出程度高出3.54%;多段塞等流度驱油方法可以明显提高中、低渗层分流率,降低高渗层分流率。因此,合理段塞组合等流度二元驱油方法可有效提高高渗透非均质油藏的采收率。     

农业信息网格数据传输资源调度方法

针对农业信息网格环境中系统负载不均衡和数据传输服务性能不高的问题,结合经典的Globus平台GridFTP传输技术和P2P技术,提出了一种P2SP(pcer to sever&peer,用户对服务器和用户)模式的农业信息网格资源调度方法.该方法既保证了系统的负载均衡性,又提高了数据传输的性能和质量,实验证明该方法是一种可行的信息网格资源调度方法.     

对等服务器网络模式

C/S模式具有较好的可管理性和稳定性,但不能自适应客户数量的变化.P2P模式可自动适应网络规模的变化,但可管理较差.对等服务器网络(P2SP)模式融合了C/S和P2P两者的技术优势,可以提高信息服务的质量,同时控制系统的成本.分析了P2SP的结构和特点,并给出了P2SP目录服务器的结构和信息认证模型.     

基于SAML2的单点登录服务器FAAS的设计与实现

单点登录是实现集中身份认证和数据统一管理的一种访问控制方法,它能够解决分布式系统的多重认证问题.在对单点登录以及安全断言标记语言(SAME)分析的基础上,设计和实现了基于SAML2的单点登录服务器FAAS(联邦认证授权服务器),并成功用于某上市企业ERP开发集成项目中.该设计的重点是SAML2的协议实现和FAAS的架构.     

一种卷板填充分层递归排样的优化算法

研究了卷板填充排样问题,提出了一种分层递归排样的优化算法。算法使用水平剪切线将卷板分层,每层的宽度和卷板宽度相同,高度和层最左端的主毛坯高度相同;通过调用递归过程确定卷板中层的排列,为各层选定主毛坯,并确定毛坯的排列方式;采用分支定界技术缩小搜索空间。实验结果说明该算法比文献中最近报道的几种算法都有效。