Impact of modern communication infrastructure on productivity,production structure and factor demands of US industries: Impact revisited

This study investigates the contribution of modern communication infrastructure characterized by high speed broadband access network on the productivity growth, production structure and factor demands for US industries and for the aggregate economy. To evaluate such contribution, we modify the traditional cost function by incorporating communication infrastructure as input in production process in conjunction with other public infrastructures. The network externality and spillover effect of broadband access technology are captured by introducing broadband penetration rate as a shift factor in industry level production function. Empirical results show that the increased use of modern communications infrastructure increases the productivity of all industries with wide variations across industries. Estimated impacts on input demands show that increase in use of communications infrastructure service saves labor and materials and increase the demand for private capital. Finally, aggregate social rate of return on such investment has been estimated for policy implications.     

互联网金融规制与市场有效性改善*——来自中国网络借贷行业的证据

中国的互联网金融经历了一个先创新发展后监管规制的过程，本文通过对网络借贷行业的实证研究，分析监管规则的出台实施对新型互联网融资市场有效性的影响。实证结果表明，网络借贷平台资金的银行存管、持有ICP证等强制性规定缓解了投资者、平台企业与借款人之间的信息不对称，对克服早期平台间通过竞相承诺高回报率来吸引投资者导致的“柠檬市场”问题、对解决网贷市场上缺乏平台风险性高低有效信号的问题都起到了正向作用，有助于互联网融资市场的有效性提高。     

民航地空通信自适应抗干扰系统设计与性能分析

在复杂电磁环境下，由于民航地空通信大频偏的要求，滤波器无法滤除波道内的干扰。针对此问题，提出了一种自适应抗干扰系统设计方法。对于落在波道内且与地空通信信号有效频带不重叠的干扰，首先对通信信号进行载波频率估计，然后使用自适应滤波方法进行干扰抑制；对于落在波道内且与地空通信信号有效频带重叠的恒包络干扰，首先重构载波信号，消除对恒包络信号估计的影响，然后根据恒包络信号的特性重构干扰信号并进行干扰分离。实验结果表明，该系统设计方法在不改变民航地空通信架构的前提下，抗有效频带外干扰的能力最大可以提升23.8 dB，抗恒包络干扰的能力最大可以提升39.4 dB，从而可以大幅提高航空飞行安全水平。     

What is happening in Paris? Airbnb,hotels, and the Parisian market: A case study

Airbnb has been the subject of heated discussions among tourism and hospitality scholars. In order to understand the true impact of P2Psharing on the tourism and hospitality landscape, it is important to understand that market in detail first. Therefore, in this paper, we explore the development of the Airbnb market over the last seven years in Paris, the most popular destination for Airbnb guests with more than 40,000 accommodation rentals. This research note is a summary of our findings on the Paris market. Our study shows different growth and seasonality patterns for Airbnb and hotels and dissimilarities in the geographical location of the offers. The findings indicate that the two products are not in direct competition and that their relationship might be more complex than previously thought. We trust that exploring the nature of the competitive relationship would be a valuable avenue for further investigation.     

Research engagement,impact and sustainable tourism

In this editorial, we reflect on how the Journal of Sustainable Tourism can contribute towards sustainable tourism researchers achieving more impact with their research. We propose some changes that can be tested in, and introduced gradually and collaboratively with, the community of the editorial board and authors. To support impactful mind sets, we will promote research that reflects diverse academic communities. To promote impactful research topics, we will encourage authors to frame their submitted articles against the Sustainable Development Goals, while research that is time sensitive will be fast tracked so it can contribute to current debates. To promote impactful methodologies, we shall favour articles that use mixed methods and action research, and those that conduct longitudinal, experimental, and evaluative research. To promote impactful partnerships, we will favour multidisciplinary approaches and research that has been co-created with stakeholders. To promote impactful communication and dissemination, we will continue to build an online community on social media for sustainable tourism researchers, we will promote articles in social media to raise their visibility, and we will provide free access to those articles that are deemed to have the greatest potential to impact positively on society.     

Twenty years of Hong Kong and Macao under Chinese rule: being absorbed under ‘one country,two systems’

This paper examines the implementation of ‘one country, two systems’ (1C2S) in the two former Western colonies, Hong Kong and Macao, as a policy innovation in managing inter-governmental relations of a large, diverse country like China. 1C2S embodies internal tensions because the Hong Kong and Chinese governments have multiple and often incompatible goals. After 20 years, these two special administrative regions (SARs) of China are gradually being absorbed.     

Sharing versus collaborative economy: how to align ICT developments and the SDGs in tourism?

Great hopes have been placed in the sharing economy to provide a new business model based on peer-to-peer (P2P) exchanges of underutilized assets. As a model, the sharing economy has been expected to make significant contributions to sustainability, providing new opportunities for entrepreneurship, more sustainable use of resources, and consumer co-operation in tight economic networks. However, in recent years, digital platforms have turned into the most important actors in the global sharing economy, turning global corporations, such as AirBnB, Booking, or TripAdvisor into intermediaries controlling and profiting from most transactions. Focused on accommodation, this paper conceptualizes the sharing economy in comparison to the wider collaborative economy, and discusses its social, economic, environmental, and political impacts in comparison to the sustainable development goals. It concludes that the sharing economy has great potential to make very significant contributions to sustainability, though the model is increasingly being replaced by the collaborative economy, which performs as an extension and acceleration of neoliberal economic practices.     

LT码新型度分布及其在电力线通信中的应用

Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC)，可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布，首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例，获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后，根据IBED在冗余度较小时译码成功率高，而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点，通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合，提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明，与其他方法及传统的RSD相比，采用新度分布进行LT编码，可明显降低译码开销，并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中，能有效地抑制PLC信道中各种噪声对电信号的干扰，并提高通信效率。