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41.
文章在经济转型和大城市人口调控背景下,研究了上海劳动力资源供需平衡趋势与外来劳动力需求情况。研究显示,在上海经济保持一定的增长速度下,2015-2020年外来劳动力需求量在700-856万人之间,这使大城市在对待外来劳动力上处于尴尬境地,一方面面临着经济发展对外来劳动力的依赖性,另一方面面临着大城市人口调控的压力。目前上海劳动力市场中外来劳动力与本地劳动力在就业岗位、工资待遇、社会福利等方面仍存在一定的差异。外来劳动力与本地劳动力在岗位上更多的是一种优势互补关系,对外来劳动力歧视有悖于社会公平理论,同时政府的强行调控政策也不利于劳动力市场的发展。政府的职责应该是尽可能地创造出健康、有序、公平的市场秩序,让市场在调节劳动力供需和结构性短缺上发挥决定性作用。  相似文献   
42.
The concepts of technology convergence or technology fusion describe the phenomenon of technology overlap. Despite evidence of the higher value associated to interdisciplinary research and cross-industry innovation, few studies have investigated the characteristics of technology fusion based on patent data. This study identifies new cases of convergence relying on the International Patent Classification (IPC) of patents filed at the European Patent Office between 1991 and 2007: the first occurrence of a patent incorporating a combination of IPC subclasses signals a new instance of fusion. Duration models are employed to investigate the impact of field level characteristics derived from patent bibliometrics on the likelihood of identifying a new fusion. The results show that merges are more frequent if the focal technology fields are closely related (based on a higher number of cross citations), are characterized by wide technological scope, and are the result of an inter-firm collaboration. In contrast to previous findings, the results show that the more complex the technologies involved, the less the likelihood of their convergence or fusion. The correlation between fusion likelihood and the characteristics of the merging fields could help managers and policymakers to predict the emergence of new technology areas.  相似文献   
43.
Airlines are able to deal with passenger growth by either increasing the frequency or the aircraft size, which may entail different numbers of aircraft movements. Forecasting the latter is necessary for evaluating technologies, approaching future emissions or anticipating capacity constraints. Purpose of this paper is to forecast a typical fleet mix and the growth of aircraft movements on flight segments worldwide based on an assumed passenger growth. The methodology is implemented in a model called Forecast of Aircraft Movements. Basic approach is the assignment of each flight segment worldwide to a distance, passenger number and aircraft category. For each combination of distance and passenger numbers a typical fleet mix is defined. The forecasted worldwide growth of passenger demand and the empirically determined fleet mix is applied to all segments in order to derive a future scenario. Assuming a certain seat load factor, the frequency growth can be deduced from the aircraft movements generated for all segments. The paper includes a forecast for aircraft movements in a future scenario based on real schedule and passenger data and gives a detailed overview of the methodology and results considering airlines' behaviour.  相似文献   
44.
This paper analyses four key markets within the European context. In this context, where the level of analyst coverage is lower than in the US setting, we aim to ascertain whether the origin of optimism in analyst forecasts in these markets is mainly strategic or whether it also contains an element of cognitive bias. Despite the fact that forecast errors lack the explanatory power to account for a significant percentage of the relationship between market sentiment and future stock returns, our new tests based on selection bias (SB1 and SB2), in conjunction with an analysis of abnormal trading volume, confirm the presence of both cognitive bias and strategic behaviour in analyst forecasts. This shows that, although regulation can reduce analyst optimism bias, the benefits are constrained by the fact that optimism bias is partly associated with cognitive bias.  相似文献   
45.
《价值工程》2012,10(20)
提出了用温度梯度量测预报隧道突水。阐述了利用掌子面温度变化预报隧道突泥突水的基本原理;结合石林隧道的工程实践,介绍了该方法的实施步骤和效果。为超前地质预报提供了一个新的途径。  相似文献   
46.
为了实现企业产品销量预估,提高生产供应的准确性与效率,提出了基于Stacking模型的融合算法进行销量预测。算法设计了两层堆叠的模型结构,初级学习器采用随机森林、支持向量回归、差分整合移动平均自回归、轻量级梯度提升机器和门控循环单元5种单模型,将分类与回归树作为次级学习器构成Stacking融合模型,并对数据进行了预测。预测结果显示,使用Stacking模型融合后得到了较好的预测结果,比单模型中效果最好的模型的均方根误差更小,平均绝对误差更小,决定系数值更大,表明Stacking融合模型的预测准确率更高。所设计模型可用于对企业店铺的产品销量进行预测,帮助企业更好地安排生产、营销活动,为减少库存、缩短生产销售周期提供数据支持,对企业生产决策有一定的参考价值。  相似文献   
47.
Disclosure and the cost of equity in international cross-listing   总被引:1,自引:1,他引:0  
In this paper, we examine the relationship between disclosure level and the cost of equity capital for a sample of international firms cross-listing on the New York Stock Exchange. Increased disclosure has the potential to reduce information asymmetry, reduce the cost of financing and increase analyst following. Using an international asset pricing model, we find that listing firms experience a decrease in both disclosure risk and systematic risk while matching firms do not. Further, we find that the magnitude of the decrease is related to three types of disclosure: accounting standards; analyst following; and exchange/regulatory investor protection. Our results suggest that increased disclosure through accounting standards is beneficial to investors and that disclosure can be accomplished through information intermediaries, e.g., analyst following. For firms with the lowest levels of disclosure prior to cross-listing, all three types of disclosure appear to be valuable.
Daniel G. WeaverEmail:
  相似文献   
48.
文章根据地面气象测报工作现状,结合笔者多年测报工作经验,谈几点提高地面测报工作质量的体会。  相似文献   
49.
王莹  吴建华 《价值工程》2011,30(10):154-155
本文是以云南省麻栗坝水库的水情测报为载体,研究开发水库水情自动监测系统中的工作体制和通讯方式优化,尽可能以较经济的方式达到充分利用水资源、洪水预报和科学调度的目的。  相似文献   
50.
文章根据地面气象测报工作现状,结合笔者多年测报工作经验,谈几点提高地面测报工作质量的体会。  相似文献   
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