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This study aims to consider the influence of density difference integral and relative flow difference on traffic flow, a novel two-lane lattice hydrodynamic model is proposed. The stability criterion for the new model is obtained through the linear analysis method.

The modified Korteweg de Vries (KdV) (mKdV) equation is derived to describe the characteristic of traffic jams near the critical point. Numerical simulations are carried out to explore how density difference integral and relative flow difference influence traffic stability. Numerical and analytical results demonstrate that traffic congestions can be effectively relieved considering density difference integral and relative flow difference.

The traffic congestions can be effectively relieved considering density difference integral and relative flow difference.

Novel two-lane lattice hydrodynamic model is presented considering density difference integral and relative flow difference. Applying the linear stability theory, the new model’s linear stability is obtained. Through nonlinear analysis, the mKdV equation is derived. Numerical results demonstrate that the traffic flow stability can be efficiently improved by the effect of density difference integral and relative flow difference.

The purpose of this paper is to explore the changes of the scale of urban tourists in mainland China under the impact of COVID-19 and, specifically, the following questions: how did the scale of domestic tourists change nationwide and in the seven geographic regions? What are the differences in the changes among the seven geographic regions? What are the changes in the hot spot areas and spatial clustering of domestic tourists across the country?

Using the data of domestic tourist arrivals in 337 cities in mainland China from 2018 to 2021, this research analyzes the absolute differences and relative differences in the scale of domestic tourists nationwide and in seven geographic divisions with the help of indicators such as range analysis, standard deviation, coefficient of variation and Herfindahl–Hirschman Index and explores the changes in the hot spot areas and spatial concentration degree of the spatial scale of domestic tourists nationwide under the influence of the epidemic using kernel density analysis and spatial auto-correlation analysis.

The absolute differences in all seven geographical divisions continue to increase during 2018–2021. The domestic tourism in southwest China is extremely uneven. Absolute differences in the northwest and northeast regions are relatively small, and the development in attracting domestic tourists is more balanced. Relative differences in southwest China are comparatively large, with the trend of uneven development being obvious. The northeast, northwest and eastern regions of China are small, and the development is more balanced. The popularity of domestic tourism in the Beijing–Tianjin–Hebei region, as well as the Yangtze River Delta region, continues to decline and then pick up in 2021. The inland southwest region became a new domestic tourism hot spot in 2021. The size of domestic tourists from 2018 to 2021 in mainland China cities shows a significant positive spatial correlation, and there is a spatial agglomeration phenomenon, but some regional agglomeration types change from 2018 to 2021.

The impact of the epidemic on the number and spatial scale of domestic tourism in China has been clarified, which makes up for the comparison of domestic tourism changes before and after the epidemic. A clear understanding of the changes in the number and spatial scale of domestic tourists in different regions after the epidemic is conducive to the development of domestic tourism revitalization strategies in accordance with the actual situation of each province and promotes the internal circulation of Chinese tourism.

This paper tries to clarify the quantitative scale of domestic tourism in different regions after the epidemic, which is conducive to the development of domestic tourism revitalization strategies in cities in different regions according to regional characteristics and the actual situation of each province and to promote the healthy operation of the internal circulation of tourism in China. This paper also tries to show the changes of domestic tourism market hot spots, agglomeration conditions changes before and after the outbreak and the clarity of tourists’ preference space changes.

Scale of domestic tourists; Absolute difference; Relative difference; Spatial hot spot distribution; Spatial agglomeration change

本文旨在探寻疫情影响下中国大陆城市游客规模演化规律, 具体而言, 疫情影响下, 全国及七大地理分区的国内游客量规模变化如何？七大地理地区的变化有何差异？以及疫情影响下, 全国国内游客空间规模的热点区域和空间集聚程度有何变化？

利用2018-2021年中国大陆337各城市的国内游客量数据, 借助极差、标准差、变异系数、赫芬达尔指等指标分析全国及七大地理分区国内游客规模的绝对差异和相对差异; 借助核密度分析、空间自相关分析等ArcGIS分析工具, 探寻疫情影响下全国国内游客空间规模的热点区域和空间集聚程度的变化情况。

①绝对差异方面, 七大地理分区的绝对差异均持续增大。西南地区的游客量的绝对差异巨大, 国内游发展极不均衡。西北地区、东北地区绝对差异相对较小, 在吸引国内游客方面发展较为均衡。②相对差异方面, 西南地区的国内游发展相对差异较大, 发展不均衡趋势明显; 东北地区、西北地区、华东地区的国内游发展相对差异较小, 发展较为均衡。③热点区域变化方面, 京津冀地区、长三角地区的国内旅游热度持续下降, 在2021年有所回升; 内陆西南地区在2021年成为新的国内游热点区域。④2018年至2021年城市国内游客量规模均呈现出显著的空间正相关的关系, 存在着空间集聚现象, 但部分区域集聚类型在2018到2021年间发生变化。

①理论意义：明晰了疫情对中国国内旅游人次的数量规模和空间规模的影响, 弥补了当前疫情前后国内旅游业变化对比的研究; 阐明了疫情前后中国城市国内游客空间格局的变化, 拓展了研究情景, 丰富了中国旅游业时空变化的相关研究。②实践意义：明晰了疫后不同地区国内旅游人次的数量规模和空间规模变化情况, 以及国内旅游市场热点变化和游客空间偏好变化, 有利于各地区城市对症下药, 制定符合各省份实际情况的国内旅游业振兴策略, 促进中国旅游业内循环。

In Germany, open‐ended funds represent the prevailing form of indirect real estate investment for retail and institutional investors. The purpose of this paper is to address whether significant performance differences occur between retail and institutional funds.

The relative fund performance of 137 funds investing in Germany and abroad are each measured against tailored Investment Property Databank performance benchmarks of direct property investments. Such benchmarks shall mimic the asset allocation of any particular fund. Data on retail fund performance are retrieved from the fund association BVI, the data on institutional fund performance are derived from the individual statements of accounts for each fund.

German open‐ended funds show significant differences in mean relative returns. The differences are mainly driven by the respective asset allocation of the funds, although relative returns against tailored benchmarks as dependent variables are supposed to offset country‐specific return fluctuations. Institutional investors tend to be better‐off than retail investors.

Liquidity holdings are not (and can not be) extracted from fund performance with the given data. In this regard, it must be acknowledged that retail funds by nature are induced to carry more liquidity. Second, the high significance of the factor asset allocation may indicate that country‐specific benchmarks could still be tailored more effectively. However, the conclusions from this paper remain unaffected. Ex post variations in the grouping of funds explain additional fund performance variance. In particular, it would be interesting to analyze the performance patterns of single‐investor funds and the influence or control that is being exercised by single‐investors in institutional funds.

Results give new insights into the performance of open‐ended real estate funds. The analysis helps explaining performance patterns and contributes to an improved understanding of the German indirect real estate investment market.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

This paper aims to clarify the necessity of taking into account the commonly neglected radiation in built environments. Ignoring radiation within acclimatized spaces with moist air, which is a participating medium, can yield inaccurate values of the relevant variables, endangering the Heating, ventilation, and air conditioning design accuracy and leading to energy inefficiencies and discomfort.

The paper uses computational fluid dynamics to predict non-isothermal flows with radiation, for both mixing and displacement ventilation strategies. The tool is applied to a lab-scale model (scale 1:30), and the results are compared with experimental data and predictions without radiation. Furthermore, the radiation influence is also assessed at real-scale level, including a parametric study on the effect of the air relative humidity on radiation.

The paper demonstrates the unequivocal impact of radiation on the flows thermal-kinematics at real-scale: ignoring radiation yields average air temperature differences of 2ºC. This becomes more evident for larger air optical thicknesses (larger relative humidity): changing it from 20 per cent to 50 per cent and 70 per cent yields maximum relative differences of 100 per cent for the velocity components and 0.4ºC for the air temperature. Nevertheless, the results for the lab-scale case are not so conclusive about the effect of moist air radiation on the thermal flow characteristics, but they evidence its impact on the flow kinematics (maximum relative differences of velocity components of 35 per cent).

The paper fulfills an identified need to clarify the relevant effects of air moisture on radiation and on the flow turbulence and thermal-kinematic characteristics for forced convective flows inside built environments.

The technological innovation of Software as a Service-Enterprise Resource Planning (SaaS-ERP) opens several relative advantages, which may be realized by choosing the proper operation mode. Thus a company looking for a new ERP system faces the question: When and under what conditions does it make sense to choose a SaaS-ERP system? The paper aims to discuss these issues.

The relative advantage criterion of the diffusion of innovation theory, derived as operation mode differences, determine the conditions under which SaaS- or On-Premise-ERP is preferable: a classification of all main systemic operation mode differences between SaaS and On-Premise for the more complex ERP systems is presented. The systemic differences were identified by analytic generalization using triangulation between a literature review and a multiple case study with four ERP producers.

The most significant decision factors between ERP operation modes are flexibility, customization, cost, and operation and maintenance. General strategies have been derived by bringing the theoretical reasons together with the operation mode difference criteria. Typical criteria for selecting SaaS-ERP are a lack of IT-capacity or capabilities, as well as high need for flexibility, due to business development, seasonality, growth, collaboration and/or expansion. On-Premise-ERPs should be selected if specific or strategic resources would be outsourced or when major customization is a need.

Case research is limited in that it reveals only ERP producers’ view and omits outlying cases.

The findings implicate that ERP selecting customers should consider and expand their criteria for ERP selection by operation mode criteria.

The classification of the most essential operation mode differences allows, for the first time, ERP selecting customers to design selection strategies. ERP selecting companies should strategically favor the operation mode that best suits their respective organizational characteristics so as to obtain the best possible support from the ERP operation modes.

This paper studies the impact of ownership structure on performance in European banking both prior and during the recent crisis. We use a panel of European banks during the period 1996–2011 and utilize random effects estimations in order to identify differences in bank performance (profitability, loan quality, and cost efficiency) due to differences in ownership structure. Both stakeholder and shareholder banks have distinct advantages, shareholder banks showing better profitability before the crisis but stakeholder banks having higher loan quality before and during the crisis. Differences in profitability and loan quality between stakeholder and shareholder banks before the crisis are especially pronounced in countries that experienced a banking crisis after 2007. There is strong a heterogeneity in performance between different stakeholder ownership groups. With the exception of private savings banks, profitability and loan quality of stakeholder banks has improved relative to that of general shareholder banks during the crisis years. The paper contributes to the previous literature by comparing pre-crisis and crisis performance and includes more refined ownership classifications. The results indicate that the survival of the stakeholder model is due to its competitive advantages. Our findings provide support for those arguing that the diversity of organizational structures is worth preserving. Ownership pluralism should become a policy objective in the banking industry.

This paper seeks to investigate the impact of citrus tristeza virus (CTV) on the commercial value of fruit produced by navel orange trees.

Data are counts of fruit of various sizes and quality harvested from a tree in a year. The counted fruit are converted to a dollar value using a standardized pricing matrix and then normalized as a ratio of the tree value compared to trees in the same orchard and year that were free of virus. Statistical tests determine if trees at various stages of infection have different production values than virus‐free trees.

On average, trees infected with CTV have higher fruit production values than trees that did not contract the virus, after compensating for climate and location differences, even though the presence or absence of CTV explains only about 1 percent of the variation in production value.

Data are from commercially maintained orchards rather than a carefully controlled experiment in an isolated greenhouse environment.

Orange growers in the region should be reluctant to remove trees that have mild strains of CTV. The effects of a tree virus on production value should be a consideration in how to respond to the virus.

Development of a standardized pricing matrix to control for pricing fluctuations from year to year is a relatively novel concept. The applied concepts of tree status cohorts and relative crop values are original and provide valuable tools for combining data from different orchards and climate conditions.