A Study on How Urban Rail Operators Can Secure New Growth Engines for the Future Approach: The Case of Underground Urban Logistics System

Seoul Metro is Seoul’s leading metro company, transporting up to 3 billion people annually. However, future ridership is expected to plummet due to an aging and shrinking population with one of the fastest declining total fertility rates in the world. The COVID-19 pandemic in 2019 accelerated this phenomenon. On the contrary, the e-commerce and home delivery industries have developed significantly since COVID-19. Seoul’s current logistics infrastructure cannot handle it. Under the inflection point of declining passenger transportation demand and increasing urban logistics demand, urban rail operators need new growth engines. Therefore, it is necessary to consider the introduction of an UULS (underground urban logistics system) that transports parcels instead of passengers through urban railways. If the UULS becomes a reality, it can be expected to secure scarce logistics land in cities, protect the environment and prevent traffic congestion by operating eco-friendly mass urban transportation, and acquire new revenue sources for urban rail operators. The UULS’s B/C ratio is 1.32. The sensitivity analysis shows that the ratio is above 1 in most cases where the unit cost of transportation is not significantly reduced.

蒙古Toson Uul油田地应力和裂缝特征及其合理开发方式浅析

从天然裂缝、地应力及水力压裂等方面简要地论述了蒙古Toson Uul油田地应力分布特征及裂缝发育特征。通过实际资料,详细分析了油田天然裂缝发育程度以及水力压裂裂缝展布规律,提出适合油藏特征的开发方式。研究成果对加深油田储层裂缝认识,指导油田制定合理开发方式以及开发后期调整具有重要意义。

候选致病岛Uu146～Uu170基因在不孕不育患者解脲支原体上的鉴定和分析

目的鉴定和分析解脲支原体（Uu）候选致病岛（PAI）Uu146-Uu170基因，并探讨其与不孕不育症的关系。方法收集女性健康组Uu51株、不育女性疾病组Uu57株；男性健康组Uu42株、不育男性疾病组Uu38株。对Uu进行生物分群，PCR扩增PAI。用Fisher精确检验法比较临床表现型、生物群分布和PAI分布之间的关系。结果女性健康组和疾病组的生物1群分别占68．6％（35／51）和73．7％（42／57），PAI的阳性率分别为15．7％（8／51）和12．3％（7／57），健康组与疾病组差异均无统计学意义（均P〉0．05）；男性健康组和疾病组的生物1群分别占71．4％（30／42）和65．8％（25／38），PAI的阳性率分别为21．4％（9／42）和18．4％（7／38），2组间差异均无统计学意义（均P〉0．05）。但女性和男性疾病组的生物2群中PAI的阳性率（5／15和5／13）显著高于生物1群中PAI的阳性率（2／42和2／25）；而女性和男性健康组中的生物1群与生物2群中PAI的阳性率差异均无统计学意义（均P〉0．05）。结论此PAI单独存在不能改变Uu对不孕不育的致病力，但可能为与Uu生物2群相关的致病因子。