银西铁路半干旱区路堤绿植生长状态研究

银西高铁宁夏段大部分路段位于半干旱区，区间路段风沙量大、积沙现象严重，路堤边坡植物常规建植期成活率较低，难以起到有效的防风固沙作用。结合银西高铁宁夏段当地区域工程特性、气象资料及土壤养分情况，提出了穴孔营养杯和三水浇灌的护苗措施；通过开展3月、4月、5月三期建植期对比试验，研究结果表明宁夏半干旱区春季3月不利于建植，而5月建植期植物成活率达到90.49%，密度达到3.25株/m2 ,盖度提高为32.74%，三项生长状态指标均优于3月和4月建植期；通过对柠条、紫穗槐和四翅滨藜3种耐旱植物的优选试验，分别对其生长状态进行了对比分析，提出了各自优选的适用范围。研究成果为半干旱区路堤绿化工程提供了技术参考。     

Women's work and wages in the sixteenth century and Sweden's position in the ‘little divergence’

We use a unique source from the Swedish royal demesnes to examine the work and relative wages of women in sixteenth-century Sweden, an economic laggard in the early modern period. The source pertains to workers hired on yearly contracts, a type more representative of historical labour markets than day labour on large construction sites, and this allows us to observe directly the food consumed by workers. We speak to the debate on the ‘little divergence’ within Europe, as women's work and gender differentials in pay is a key indicator of women's relative autonomy and seen as a cause for the economic ascendency of the North Sea region during the period. We find small gender differentials among both unskilled and skilled workers, indicating that Sweden was a part of the ‘golden age’ for women. We argue that despite superficial equality, women's economic outlooks were restrained in many other ways – including their access to higher-skilled work and jobs in the expanding parts of the economy – adding important nuance to the discussion about the relationship between women's social position and economic growth in the early modern period.     

一种新的光伏发电预测模型的设计

为了对光伏发电的输出功率进行预测,本文分析光伏发电的影响因素,提出了一种基于太阳辐射功率曲线匹配的预测模型。该模型将历史数据按时段进行分解,查找与当前时段太阳辐射功率曲线最为匹配的数据,以此构建并训练BP神经网络,来预测未来3个小时内的太阳辐射功率,能够较好的实现预测目标。实验结果表明,该模型有较高的精度,可对电网调度起到重要的指导作用。     

发电企业运营期的资金管理研究 ——以Z发电企业为例

2021年,随着煤炭市场价格的不断高企,大用户直供交易和竞价上网等规模的不断扩大,发电企业的盈利能力水平遭受大幅度的削弱,火电行业整体处于亏损的经营局面,发电企业的生存环境极度恶化。如何在不断变化的市场环境中生存下来,是发电企业不得不面临的一个重要问题,本文以Z发电企业为例,通过对Z发电企业的资金管理现状进行剖析,制定出行之有效的具体措施,以期进一步提升发电企业的资金管理能力和创效水平。     

BOT项目特许权期决策方法研究

特许经营期长短的决定是高速公路BOT特许权经营的一个核心问题。由于在特许经营期的确定直接关系到东道国政府和项目公司的利益分配,如果特许权期限较长,东道国的利益受损;特许权期限较短则会影响项目公司的利益,这都会导致BOT项目的失败。本文分析了一些影响特许权经营期的因素,并分析了这些因素对特许权经营期决策的影响,建立了基于蒙特卡罗方法来确定特许经营期的模型,从而提供了更系统的理论方法来判断和决策BOT项目特许经营期。