The European refugee crisis and the natural rate of output

The European Commission follows a harmonized approach for calculating structural (potential) output for EU member states that takes into account labour as an important ingredient. This article shows how the recent huge migrants’ inflow to Europe affects trend output. Due to the fact that the immigrants immediately increase the working population but effectively do not enter the labour market, we illustrate that the potential output is potentially upward biased without any corrections. Taking Germany as an example, we find that the average medium-term potential growth rate is lower if the migration flow is modelled adequately compared to results based on the unadjusted European Commission procedure.     

我国软件外包承接城市效率评价与驱动因素研究

就 业问题、环境污染以及从业人员研发能力下降已经成为制约软件外包承接城市发展的瓶颈问 题。文章运用DEA方法构建考虑非期望产出和非合意变量的软件外包承接效率评价模型，重 点比较不同模型下我国软件外包承接城市效率的差异，并引入Tobit回归分析软件外包承接 城市效率的驱动因素。研究发现：我国软件外包承接城市的投入产出组合在逐步优化，且东 部沿海城市的效率值明显优于中西部城市，其中大连市的效率值始终为1，处于生产的前沿 面。另外，人才竞争力对软件外包承接城市效率有显著的正向影响，信息技术基础设施竞争力与承接效率的关系呈显著负相关。     

基于通勤行为的小城镇土地利用与格局优化对策研究——以扬中市为例

研究目的:从居民的通勤行为特征中寻求小城镇土地利用格局优化路径,为产城融合的实现提供理论支持。研究方法:构建通勤流矩阵,运用Arc GIS路径分析测算通勤距离,并通过缓冲区分析通勤距离在空间上的特征,并与土地利用类型进行对比分析,同时建立通勤距离与社会经济因素的回归方程,分析通勤距离的影响因素。研究结果:小城镇通勤方式以便捷型工具为主,通勤高峰集中于上下班,通勤距离随着城镇化和工业化水平的提高,短距离占比增大。主要结论:在城镇化和工业化发展较快的区域,短距离通勤集聚更具有"同心圆"特征,核心力更强。工业化带动的聚集结构呈现出"条带形"态势,与区域工业布局结构有较密切的关系,也与城镇化和工业化扩增融合有关。短距离通勤集聚区会随着城镇化水平的提高而由"双核"向"单核"结构发展,并针对以上问题提出了相应的对策。     

华为负值PBGT切换技术应用

负值PBGT切换技术的实现和分层分级算法相似,但比分层分级算法更加灵活,它是移动通信系统中非常重要的技术。现通过工程实践多次使用网络优化工具设置负值PBGT切换参数,实现在双频网优化上的应用,可以避免乒乓切换引起掉话,该技术的应用有重要的现实意义。     

浅谈价值工程在地下管线探测项目设计方案评价中的应用

价值工程作为一种将功能与成本、技术与经济相结合而进行技术经济评价的方法,又称为价值分析。本文通过结合地下管线探测项目的具体实例,探讨了在具体的施工过程中,为了在降低工程成本的同时能够有效的保证施工工程的质量和进度,如何采用价值工程的方法选择以及优化施工组织设计的方案。实践证明,在施工项目中应用价值工程的方法不仅能够完善施工方案,还能有效确保施工进度并且能够有效提高利润,最重要的是还能够很好的保证施工质量。     

输出假设理论对我国英语教学的启示

语言学家Swain所提出的语言输出的功能和输出假设模式是语言学研究的重要理论,系统了解输出假设理论会对我国英语教学产生积极的启示。当前我国的英语教学中存在一个突出问题,那就是"高分低能、哑巴英语、费时低效"。在英语教学实践中,重视语言输出作用,强化输出练习有助于解决这一问题。     

The shared environmental responsibility principle: new developments applied to the case of marine ecosystems

Estuaries provide advantageous sites for both harbors and fish habitats. In many countries, harbor expansion in estuaries contributed to the decline of fish populations with impacts at the global scale. Restoring these habitats is important to prevent a global biodiversity crisis but is costly and potentially unaffordable for polluters under the Polluter Pays Principle. Such affordability issues prompt decision-makers to reduce environmental targets of restoration programs. Harbor infrastructures destroy fish habitats but generate benefits for society and contribute to the public interest, raising some questions on who is responsible for environmental degradations and who can afford environmental restoration costs? One way to allocate restoration costs is to analyze the amount of harbor services consumed by economic sectors. This paper addresses these questions by computing burden sharing scenarios with an input–output matrix. These scenarios are simulated under the shared responsibility principle to distribute restoration costs among stakeholders in the Seine estuary, France.     

Pareto efficient allocation of an in-motion wireless charging infrastructure for electric vehicles in a multipath network

Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.     

Government spending multipliers in contraction and expansion

This paper investigates the impact of government spending on output and the size of the spending multiplier during periods of output contraction and expansion. It also investigates the impact of spending when the economy hits the nominal zero lower bound. It uses a panel of 21 advanced countries over the period of 1979–2011, applying a TSLS estimation technique. We find a spending multiplier of close to 1 during expansion and values of up to 3 during contractions. However, our results do not indicate a difference in the impact of spending during nominal zero lower bound periods.     

Diversified behavioral portfolio as an alternative to Modern Portfolio Theory

The traditional mean–variance approach has been complemented by alternative theories that use risk measures different from standard deviation of returns or involve additional distributional features of returns like skewness and kurtosis. We propose a portfolio choice model that combines different distributional characteristics of the returns in the decision-making making process, considering preferences of investors which are modeled as non-statistical uncertainties of investors using fuzzy theory. We use 20 stocks of the S&P500 from January 2013 to December 2017. We assess the obtained portfolios’ performance, and the diversified behavioral portfolios outperform than the mean–variance portfolio. This methodological proposal can be seen as a strong managerial tool to make investment portfolio decisions.