Emergency business management and internet connectivity

Many technology experts believe the internet cannot be shut down as it was built by the military to be redundant. Organizations have accepted this premise and generally do not have the means to ensure continuing connectivity in the face of disruption. As early as 1997, however, the internet did experience disruption, leaving millions of users disconnected. It is argued that because the internet has been embedded into all business operations it is necessary for managers to review their policies regarding continued connectivity should a disruption occur. In this article I offer several practical suggestions regarding how managers can continue to operate critical processes in the face of short or extended internet outages. Further, I suggest that a view of corporate data processes based on traditional accounting perspectives needs to be revised to consider these data processes as a matrix interacting across customer, vendor, employee, and human interfaces.     

A two-methodology comparison study of a spatial gravity model in the context of interregional trade flows

This article argues that the introduction of spatial interactions to model the determinants of origin-destination (OD) flows can potentially result in excessive contiguity. To explain flows between OD regions, it is not only what happens in the origin and destination that is relevant, but also what happens in their neighbouring regions. However, what happens if there is a high degree of overlap between origin neighbouring areas and destination neighbouring areas? The article presents an empirical illustration to re-examine the evidence presented in previous research (Alamá-Sabater et al., 2013) and more closely analyses the territorial level, focusing on the case of interregional trade of goods at the NUTS3 level (Spanish provinces). We then use two different methodologies within the framework of a spatial gravity equation for interregional trade modelling. The findings confirm the importance of spatial dependence on trade flows and in particular that logistics decisions within a province affect shipments from contiguous provinces.     

Infrastructure and Connectivity in India: Getting the Basics Right

Infrastructure helps in building productive capacity by bridging connectivity gaps, reducing distribution and trade costs, and facilitating the sharing of the benefits of growth with poorer groups and communities, among others. The evidence in this paper suggests the need for India to develop both hard as well as soft infrastructure for enhancing trade flows and growth. The existence of both aspects simultaneously will produce gains of a significantly higher order but one without the other is likely to be ineffective.     

A strategic model of port-hinterland freight distribution networks

This paper presents a strategic model for port-hinterland freight distribution networks. The approach utilizes a combination of a multi-objective optimization model to estimate locations and networks of distribution centers and an assignment model that recognizes distributed service level preferences. Our example application concerns the European continent and is transferable to other regions. The model calibration is able to explain the European port-hinterland distribution structures satisfactorily. We compute novel performance measures that take into account port-hinterland distribution structures. The measures include port-hinterland transport cost, port-hinterland transport time, and distribution center-hinterland transport time. These measures can provide inputs for port-connectivity studies.     

Airline delay management problem with airport capacity constraints and priority decisions

This paper deals with the Airline Delay Management Problem (ADMP), which can be described as the task of dealing with daily airline operational delays and deciding whether to delay subsequent flights at a hub airport or to have them departing on time. An innovative integer linear programming approach is presented to the capacitated case of the ADMP and airport limitations in terms of bay availability, taxiway capacity and runway separation are incorporated to represent capacity constraints. Fuel cost, passenger compensation, and passenger inconvenience costs are included in the objective function. The decision variables include the re-timing of flight departures and arrivals, the use of the airport capacity over time and the rebooking of passengers in case of missed connections. To guarantee the linearity of the optimization model and fast computational times, a receding horizon modeling framework is adopted. The approach is applied to a case study using real operational and passenger data from an international hub-and-spoke carrier. The case study shows the capability of the linear model to deal with a complete day of operations within a few minutes. The results suggest that the proposed approach can lead to cost reductions of almost 30% during recovery, when compared with the solution from the airline. In addition, a sensitivity analysis is provided to investigate the impact of not including passenger inconvenience costs and of reducing runway capacity.     

基于最小耗费距离模型的西山区生态连接度评价

针对目前生态连接度评价空间显式表达的不足,提出一种基于最小耗费距离模型的评价方法。按照不同生态功能分区,计算土地生态服务价值、障碍影响指数及生态连接度指数,并对影响土地生态连接度的驱动机制进行深入分析。以云南省西山区2009年、2015年土地利用数据和2020年土地规划数据为例进行验证。结果表明:基于最小耗费距离模型和GIS方法可以显式的表达研究区生态连接度的空间差异程度;研究区2009—2015年生态连接度下降,是因为"十二五"期间经济快速发展及城市化进程加快,无序蔓延式扩张致使绿地被分割、耕地被占用;规划末期2020年生态连接度逐渐趋于好转,源于"十三五"高度重视生态保护,大量风景名胜区和生态湿地的建立对生态环境具有很好的促进作用。该方法可为生态连接度定量分析评价及驱动机制研究提供借鉴和参考。     

区域景观格局视角的绿地生态网络优化研究*——以徐州为例

[目的]基于景观格局演变的区域绿地生态网络与生态功能优化研究是景观生态学研究的热点领域之一。[方法]文章以徐州示范为例,在城市研究区景观格局演变及其异质性研究分析基础上,探索城市规划区城乡绿地景观格局的优化路径;运用经济学与生态学原理,按“山水林田湖草”一体化理念,以区域生态系统服务优化及人与自然和谐发展为前提,从市域与城市规划区视角,合理配置城乡绿地生态网络景观组分,进而优化区域绿地生态网络。[结果]研究得出2005—2015年研究范围城市化造成大量耕地消失,城市建设用地快速增加,随着生态园林建设的快速推进,林地面积占比大幅度增加;地表覆被变化直接表现为景观格局的快速破碎化和景观多样性的下降,景观类型的丰富度和复杂度急需提高,景观多样性指数、景观均匀度指数也均呈现较为明显的下降趋势。同时,重点提出了强化景观格局与过程的完整性与连通性,挖掘潜在生态功能等的区域绿地生态网络一系列优化方案。[结论]文章为研究区及延伸的城乡区域绿地生态网络构建和生态系统服务优化提供了科学的依据、方法与途径。     

江苏经济增长的动力因素分析

20世纪90年代中期以来,江苏经济取得了持续、快速增长.文章运用灰色关联分析方法,从总量、产业、消费、投资、科技、政府作用、对外开放等方面分析了江苏经济增长的主要因素,结果表明:主要动力源于消费、第三产业、工业、投资等因素,但与科技、全员劳动生产率等因素关联性偏小.据此,文章提出了加快科技创新、优化产业结构、刺激消费、强化政府公共职能等对策与建议.     

Long memory in the high frequency cryptocurrency markets using fractal connectivity analysis: The impact of COVID-19

In this paper, we study the long memory behavior of the hourly cryptocurrency returns during the COVID-19 pandemic period. Initially, we apply different tests against the spurious long memory, with the results indicating the presence of true long memory for most cryptocurrencies. Yet, using the multivariate test, the series are found to be contaminated by level shifts or smooth trends. Then, we adopt the wavelet-based multivariate long memory approach suggested by Achard and Gannaz (2016) to model their long memory connectivity. The findings indicate a change in persistence for all series during the sample period. The fractal connectivity clustering indicates a similarity among Ethereum (ETH) and Litecoin (LTC), Monero (XMR), Bitcoin (BTC), and EOC token (EOS), while Stellar (XLM) is clustered away from the remaining series, indicating the absence of any interdependence with other crypto returns. Overall, shocks arising from COVID-19 crisis have led to changes in long-run correlation structure.     

Effects of enhanced air connectivity on the Kenyan tourism industry and their likely welfare implications

This paper investigates the links between air connectivity, tourism benefits and welfare. It improves on the common practice in the literature by demonstrating avenues of tourism expansion and their welfare implications using both a partial and a general equilibrium model. The results of the gravity model show that there is a strong connection between air connectivity factors and incoming passengers. Simulation results of tourism expansion brought about by improved connectivity demonstrate that all household groups experience an improvement in their welfare but with lower impact on low-income agricultural households. The study concludes that formulating policies that address the air connectivity gap in Kenya would benefit the tourism sector and all households if co-ordinated with rural development initiatives.