汽车制造商分时租赁模式采用及产品线策略研究

考虑自有平台和第三方平台两种分时租赁方式,将汽车质量划分为性能质量和环境质量,构建销售模式、纯分时租赁模式和混合模式下的产品线策略模型,研究制造商产品线策略与商业模式之间的相互作用。研究发现,同品牌产品间竞争和合并效应是分时租赁模式影响产品线策略的两个关键因素。同品牌产品间竞争的加剧和合并效应的增大都会激励企业选择性能更好的车型而忽略其环境表现。分时租赁模式能同时改进利润与产品环境表现,但存在条件:当消费者价格敏感性较低时,使用成本高且合并效应小是实现同时改进的条件;当消费者价格敏感较高时,使用成本低且合并效应小则是同时改进的条件。     

On Riemann-Finsler geometry

The history of Finsler geometry is reviewed and briefly recent development in Finsler geometry and its application is completed systematically. Furthermore, an interesting open problem has been proposed in this field.     

非线性机电系统数学建模的联结方法

由于传统建模方法缺乏通用性,发展通用建模方法已成为必要．在总结了传统的机电系统数学建模优缺点、引入位移联结、速度联结和加速度联结概念的基础上,提出了适用于非线性机电系统数学建模的通用方法——联结方法．将联结理论从线性系统拓宽于非线性系统,拓展了联结理论．将联结方法与传统的拉格朗日法进行对比,说明了联结方法可避免建模过程中严重偏微分运算的优越性,并从理论上证明了研究结果的可靠性．     

旋转水流消能及其空化特性

研究了高水头（Ｈ〉２００ｍ）泄水建筑物隧洞内部消能的一种新型消能工,将竖井与隧洞切向连接,在隧洞内形式螺旋形的旋转水流,这种水流结构可消散水流中大部分能量,使流向下游的水流剩余能量较小,减轻下游的消能负担和减少下游冲刷。这种消能工的最基本的水流形态环流,在其固体边壁存在着较大的离心力,其中心为大气压,整个水流不会出现负压,流速迅速降低,空化特性较好,不会产生空化与空蚀。还分析了旋转水流的消能机理、     

用户中继热线自动接续系统

提出以单片机为核心构成自动接续装置,检测程控交换机中继线路的直流状态和交流信号音,实现“热线电话”中继线路的自动接续．     

从切丛的微分几何看Finsler联络的比安基恒等式

应用切丛微分几何中Ｎ－分解的理论,证明Ｆｉｎｓｌｅｒ型线性联络的两个比安基恒等式等价于Ｆｉｎｓｌｅｒ联络的１１个比安基恒等式。     

Detection of single nucleotide polymorphisms using electrospray ionization mass spectrometry: validation of a one-well assay and quantitative pooling studies

Single nucleotide polymorphisms (SNPs) are currently being mapped and databased at a remarkable pace, providing a viable means for understanding disease susceptibility, differential drug response and human evolution. Consequently, there is an increasing demand for SNP genotyping technologies that are simple, rapid, cost effective and readily amenable to automation for high-throughput analyses. In this study, we improved the Survivor Assay, a SNP detection method based on electrospray ionization mass spectrometry (ESI-MS), with several developments. One improvement is the development of a one-well assay, requiring no off-line purification of the polymerase chain reaction product, achieved by simple addition of reagent solution into a single well. Another is the on-line separation of magnesium and dideoxynucleotides using an in-house made monolithic metal chelating column, eliminating any off-line sample preparation prior to mass spectrometric analysis. Here the Survivor Assay is extended from a proof-of-principle concept to a validated method by genotyping six SNPs from five different regions of human genomic DNA in 55 individual samples with 100% accuracy. This improved Survivor Assay eliminates the tedious and time-consuming steps of sample preparation, minimizes sample handing and offers a high-throughput analysis of SNPs by ESI-MS. The current combined preparation and analysis time is 2 min per sample. The simplicity of this method has potential for full automation and parallel chromatography and, thus, reduced analysis time. In addition, we have adapted the Survivor Assay for quantitative SNP analysis in pooled DNA samples. The capabilities and sensitivity of this approach were evaluated. We demonstrate that an allele occurring at a frequency of 2% can consistently be quantitated.     

All-glass open-split interface for capillary GC/MS

This paper describes a design for an all-glass GC/MS interface. The design has advantages due to low dead volume, lack of column effluent adsorption and degradation, simple interface production and installation, and ease of column mounting/dismounting.     

J2EE架构下的数据库访问技术分析与研究

本文讨论了基于J2EE的数据库访问方法，并对各方法的实现进行了比较，给出了在实际开发中数据库访问方法选择的建议。     

从当代西方环境伦理学看韩愈的天人感应论

韩愈的天人感应论属于我国古代天人感应论的第四种类型，他从“天入相乖”、“祸善福淫”的角度提出了天与入感应的独特方式。从当代环境伦理学视角看，韩愈的天人感应论表达了对大自然的道德关怀，与当代环境伦理学一样，具有强烈的反传统人类中心主义倾向以及相似的基本原则和道德目标。在环境问题日益严重的今天，探讨韩愈的天人感应论，对我们坚持科学发展观，处理好发展经济与保护环境的关系，搞好社会主义和谐社会建设，具有一定借鉴意义。