Air Afrique: the demise of a continental icon

Although the rationale for multi-flag airlines' formation is rooted in contemporary strategic thinking, our understanding of their emergence and subsequent mass disappearances in the twentieth century remains an elusive issue. This article seeks to fill this void by examining the emergence, ascendency and demise of Air Afrique, an airline once seen as a symbol of regional integration in Africa. This examination takes a historical perspective and covers the period from 1961 to 2002. On the basis of this historical analysis, five distinct stages have been identified reflecting the firm's glorious days, precipitous decline and subsequent collapse. These are: the golden age; Africanisation; escalating indecision, escalating commitment and dissolution phases. Each phase provides insights into the deterministic and voluntaristic perspectives of organisational failure. The implications of the findings of this research for theory and practice are discussed.     

省直管县改革与区域空气污染——来自卫星反演数据的实证证据

从政府治理结构改革的角度探讨如何推进环境污染治理是一种有益的尝试。从理论上来说,省直管县改革作为一种重要的政府治理结构改革,能够通过简化政府治理级次来改变政府治理效率,影响诸如环保等公共产品和服务的供给。本文采用卫星反演的PM2.5数据检验了省直管县改革前后县级区域空气污染的变动趋势。发现“财政省直管县”改革能显著降低地区空气污染水平,“强县扩权”改革则显著加剧了地区空气污染。稳健性检验、进一步的分析结果均支持上述结论。机制检验发现,“财政省直管县”主要体现为财力保障水平提升导致的治理变化,而“强县扩权”则主要体现为地方政府竞争行为改变导致的空气污染治理变化。总之,单纯的政府级次减少可能并不必然利于地方公共服务的提供,良好的财力保障为地方污染治理服务提供了支撑,竞争行为变化带来的改革效应则会受到政府对环境污染重视程度的显著影响。     

Analyzing air cargo flows of international routes: an empirical study of Taiwan Taoyuan International Airport

Air cargo demand is an important aspect of the operation and planning of private and public agencies responsible for airports. While most existing studies in this field include only geo-economic characteristics of airports and their hinterlands as explanatory variables, this study develops a gravity model of air cargo flows by trying to incorporate more factors that might influence international air cargo flows of an airport. The model is developed based on the panel data of air cargo services on scheduled routes at Taiwan Taoyuan International Airport during the years 2004-2007. The results indicate that population, air freight rate and three dummy variables, including the regional economic bloc of the “Chinese Circle”(an informal partnership between Hong Kong, Macao, Taiwan and mainland China), the Open Sky Agreements and long established colonial links, are key determinants of international air cargo flows from/to Taiwan. These results suggest a wider array of factors needs to be considered in policy.     

Economies of traffic density and scale in the integrated air cargo industry: The cost structures of FedEx Express and UPS Airlines

This paper examines the cost structures of the leading integrated air cargo carriers, FedEx Express and UPS Airlines. A total cost model is estimated for the two carriers using quarterly data on domestic operations and costs over a nine-year period (2003–2011). The estimated model indicates that the integrated industry exhibits increasing returns to traffic density and constant returns to scale. Accounting for carrier-specific differences in cost structure and network size, FedEx Express is found to be more cost-efficient than UPS Airlines. Looking at the carriers individually, UPS Airlines exhibits substantial economies of traffic density and constant returns to scale while FedEx Express' cost structure is characterized by weak economies of density and constant returns to scale. The combined effect of returns to density and returns to scale on the cost structures of integrated carriers is captured by economies of size. Both FedEx Express and UPS Airlines exhibit economies of size, indicating that carriers in the integrated industry can be more cost efficient by making appropriate adjustments to their network size as their output grows. Moreover, the relative cost-efficiencies of the carriers are reversed when their network-size differences are not controlled.     

北斗卫星导航系统应用推广中的冲突与应对策略

随着北斗卫星导航系统的不断完善以及民众国家安全意识的提高,北斗系统必将主导国内市场并进入国际市场。加快启动北斗系统的应用推广工程具有十分重要的政治、经济和社会意义。在宏观研究层面上,基于系统科学理论,提出了北斗系统应用推广的系统工程观点以及注重冲突分析应用价值的基本思想,对后续的中观和微观研究具有启示作用。     

谈贵港港平南港区武林作业区二期工程对航道的影响

文章全面分析了贵港港平南港区武林作业区二期工程建设前后水位的变化、工程河道动力轴线的变化,以及工程对河槽、岸线、河势稳定的综合影响,工程建设对上下游航行条件、临河建筑物及航道远期发展规划的影响,并对工程建设后河道冲淤以及船舶靠泊、离泊、调头作业航线等进行分析。     

Policy impacts on the propensity to travel by HSR in the Amsterdam – London market

This paper investigates the impacts of possible measures to enhance HSR market share in the London-Amsterdam market. To this aim, we adopted a two-level aggregate nested logit model able to jointly model trip distribution and trip generation, thus taking into account that the tested policies may increase or decrease the overall demand. The model was applied to an extensive dataset about passenger flows traveling between London airports and HSR station and Amsterdam in the period 2015–2019. The results show that both the reduction of HSR fares and the application of an air ticket tax, albeit with different impacts in terms of stimulus or reduction effect on overall demand, are ineffective in increasing HSR market share, if not adequately supported by improving HSR service. Increasing HSR frequency and reducing HSR travel times constitute the best opportunities to increase HSR ridership by stimulating a higher substitution effect than modifications in relative fares. Lastly, the recent queueing at airports, following staff shortages and strikes, significantly lower air transport demand and potentially has a substantial upward effect on HSR market share.     

我国沪深股市同配性和网络导航现象研究——基于复杂网络理论

分别按照地区、行业、市值三种分类标准对我国沪深市场股票进行分类,以股票为网络节点,研究了三种分类标准下的股票同配性,进而研究了行业分类标准下的网络导航现象。结果表明:上海市场和深圳主板市场在阈值较高、按行业分类时表现出较为明显的同配性;沪深股市在阈值较低时表现出一定的异配性,而当阈值达到一定程度时表示出较强的同配性;网络导航现象体现了股市中异类股票间的相互影响作用;中国股市存在较多的网络导航现象;在较长时期内造成该现象的主要原因是分类标准不准确、股票涉及共同的炒作概念、具有共同的股权投资对象、新股上市日期相近等,短期内的原因还包括消息面或事件性的驱动因素。     

G公司内部控制变革研究——从会计控制到高级导航系统

控制论和权变理论认为,公司内部控制应根据其所处的内外部条件随机应变。G公司为应对内外环境的变迁实施了"新一代内部控制",并将其定位为"高级导航系统",以强化内部控制的决策支持作用。研究发现,G公司内部控制变革的驱动力主要来自环境的变化,多次并购引起的规模扩张及自身组织结构变化;新的控制系统在控制目标、控制方法、重点控制领域、新的信息系统构建、组织结构及内部控制实施人员的角色再定位等方面进行了变革。本文在内部控制变革框架基础上,通过对内部控制部门员工实施问卷调查,检验了该公司从传统的会计控制到新一代内部控制转变的效果。     

Implementing technology-forcing policies: The 1970 Clean Air Act Amendments and the introduction of advanced automotive emissions controls in the United States

Technology forcing is a strategy where a regulator specifies a standard that cannot be met with existing technology, or at least not at an acceptable cost. Using the 1970 U.S. Clean Air Act for controlling automobile emissions as a baseline example, we demonstrate the importance of the regulatory implementation process if regulations are to foster technological change. The 1970 legislation required steep emissions reductions for new 1975 and 1976 automobiles, which presented automakers with major technical and economic challenges. Nevertheless, the U.S. Environmental Protection Agency successfully forced the adoption of two marquee control technologies—the catalytic converter in 1975 and the three-way catalyst in 1981. We focus on three factors critical to the implementation process: agency credibility to enforce standards, competitive pressures to drive industry research and development, and uncertainty about technological development.