Panel unit root tests under cross section dependence with recursive mean adjustment

Utilizing recursive mean adjustment (RMA) we provide two unit root tests: the covariate RMA unit root test and the panel feasible generalized RMA unit root test. The proposed panel unit root tests are precise and powerful, especially when T > N.     

中部地区实现跨越式发展的路径选择

中部六省地处祖国内陆腹地,在全国地域分工中扮演着十分重要的角色。如何有效发挥中部地区综合优势,加速在全国区域经济板块中崛起,是摆在我们面前的重大课题。文章立足中部六省现状,在深入分析中部地区拥有的各项优势后,指出后发优势战略与比较优势战略相结合,大力发展混合所     

Housing Vouchers,Tenant Quality,and Apartment Values

Landlords face unique concerns in maximizing profits when they accept subsidized as well as unsubsidized tenants. Subsidized tenants come with lower rental collection risk because part or all of the rent is paid by a public agency and accepting subsidized tenants may widen the potential tenant market. But subsidized tenants tend to reduce overall tenant quality and to impose higher operating costs. By accepting subsidies, landlords may also subject themselves to periodic site inspections that may increase capital costs. Further, subsidized tenants may eventually crowd out unsubsidized tenants, lowering the average quality of the resident mix. Tests from Washington, DC apartments on accepting and advertising for Section 8 tenants support these qualitative predictions. Accepting Section 8 tenants enhances revenues, but advertising for them lowers revenues. More aggressive solicitation of subsidized tenants leads to a crowding out or displacement risk that dominates over any diminished collection risk.     

GPS RTK技术及在架空送电线路测量中的应用

文章结合横县220kV线路测量的实践,讨论了GPS RTK技术及在送电线路测量中的应用。     

关于电磁场边界条件的另一种合适推求

本文在两个层次上(首先,在一般小直圆柱状盒子面或小长方形回路上,其次,在任意形状小闭合面或小闭合回路上),摒弃不必要的假设,充分利用各个相应矢量在微元范围内为一恒矢量这一特点,从而,合乎逻辑地推得电磁场边界条件。     

How Informative Is Floating NAV When Securities Trade Infrequently?

We examine if a floating net asset value (NAV) increases the transparency of risk for investors. Using closed‐income fixed income funds we find little evidence that a floating NAV helps investors better understand the value and risk of a fund when a fund's assets trade infrequently. This potentially informs the debate regarding the adoption of a floating NAV in the money market industry. Our results suggest that it is unlikely that the benefits of floating NAV will outweigh the costs.     

Transdisciplinary Research in Sustainable Operations – An Application to Closed‐Loop Supply Chains

This contribution provides implications for academic research and practitioners, as it identifies the lack, necessity and major benefits of transdisciplinary research and the collaboration of academics and industry in order to fulfill the goals of a sustainable supply chain. Closed‐loop supply chain management is a major contributor to implementing sustainable operations. An essential prerequisite for successful realization is the expertise and cooperation of representatives from engineering, management and natural sciences as well as practice. We identify a need for transdisciplinary collaboration within two steps. First, a literature review points out that various research disciplines as well as practice mostly operate in isolation. Second, we develop a framework that highlights the benefits of collaboration between these research areas. This paper provides an overview to better understand current trends in this complex field, which is a rich area for research that is still in its infancy. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment     

尿素车间一段分解塔筒节局部减薄原因及防范对策

对某化肥公司尿素一段分解塔筒节进行了宏观检验、仪器测量和壁厚校核。根据实际检验情况对尿素一段分解塔筒节的腐蚀原因进行了分析。结合实际情况对尿素一段分解塔筒节的修理和使用提出了防腐措施。     

北美新一代合作社经验对中国林业合作社发展的启示

相比于农民专业合作社,国内学者对于林业合作社的研究还相对较少,但随着集体林权制度改革的逐步落实,越来越多的个体经营的林农会希望通过加入合作社来提高组织化程度,共同抵御市场风险,最终实现提高林业经营收益的目标。通过介绍北美新一代合作社组建、发展过程中的成功经验,初步探索适合当前中国林业合作社发展状况的合作社规范化发展措施,力图通过具体措施的实施来实现促进中国林业合作社更好更快发展的目的。