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Unmanned aerial vehicles (UAVs) have been undergoing fast development for providing broader signal coverage and more extensive surveillance capabilities in military and civilian applications. Due to the broadcast nature of the wireless signal and the openness of the space, UAV eavesdroppers (UEDs) pose a potential threat to ground communications. In this paper, we consider the communications of a legitimate ground link in the presence of friendly jamming and UEDs within a finite area of space. The spatial distribution of the UEDs obeying a uniform binomial point process (BPP) is used to characterize the randomness of the UEDs. The ground link is assumed to experience log-distance path loss and Rayleigh fading, while free space path loss with/without the averaged excess path loss due to the environment is used for the air-to-ground/air-to-air links. A piecewise function is proposed to approximate the line-of-sight (LoS) probability for the air-to-ground links, which provides a better approximation than using the existing sigmoid-based fitting. The analytical expression for the secure connection probability (SCP) of the legitimate ground link in the presence of non-colluding UEDs is derived. The analysis reveals some useful trends in the SCP as a function of the transmit signal to jamming power ratio, the locations of the UAV jammer, and the height of UAVs.

Progressive cities worldwide have demonstrated political leadership by initiating meaningful strategies and actions to tackle climate change. However, the lack of knowledge concerning embodied greenhouse gas (GHG) emissions of cities has hampered effective mitigation. We analyse trans-boundary GHG emission transfers between five Australian cities and their trading partners, with embodied emission flows broken down into major economic sectors. We examine intercity carbon footprint (CF) networks and disclose a hierarchy of responsibility for emissions between cities and regions. Allocations of emissions to households, businesses and government and the carbon efficiency of expenditure have been analysed to inform mitigation policies. Our findings indicate that final demand in the five largest cities in Australia accounts for more than half of the nation's CF. City households are responsible for about two thirds of the cities' CFs; the rest can be attributed to government and business consumption and investment. The city network flows highlight that over half of emissions embodied in imports (EEI) to the five cities occur overseas. However, a hierarchy of GHG emissions reveals that overseas regions also outsource emissions to Australian cities such as Perth. We finally discuss the implications of our findings on carbon neutrality, low-carbon city concepts and strategies and allocation of subnational GHG responsibility.

Background: In China, there was a pressing need to establish a governmental agency to oversee the organizations that provide public health and medical services. The Chinese Health Inspection Authority (HIA), a relatively independent organization functioning at each administrative level (provincial, municipal, and county), was mandated to conduct 11 health inspection functions to maintain efficient public health and medical services. These functions include issuing health permit, conducting health supervision and inspection, health testing and evaluation, case investigation, complaint handling, managing public health crisis, monitoring and safeguarding public health at major public events, enforcing supervision and inspection compliance, public health education, information management, and team training and management. Since the reform of the health inspection system by the Ministry of Health in 2000, the HIA underwent a series of changes and transitions. This study aimed to describe and assess the five factors that were considered to be important for meeting service delivery objectives of the HIA in the People's Republic of China. Methods: A total of 604 HIAs, sampled across three geographical regions of China at three administrative levels, participated in a cross-sectional survey conducted in 2013. Descriptive statistics were used to analyze the status of mandated operations, manpower, revenue and expenditures, and institutional infrastructure. Differences in these characteristics across the geographical regions and administrative levels were compared.Results: On average, the HIAs had not fully implemented the 11 mandated functions at any administrative levels. Governmental financial allocations were the main sources of revenue. Three primary personnel employment models coexisted and most employed the quasi-civil service employment model. The institutional infrastructure did not meet governmental mandated standards with respect to building area or the number and types of equipment available to conduct key functions. Conclusions: In 2012, the majority of the HIAs in China at the provincial, municipal, and county levels did not meet the mandated requirements, although positive indications toward meeting these requirements were observed. It is necessary for the government to pay more attention to institutional resources (buildings, equipment, and the level of the staff's educational attainment) and ensure that the HIAs can meet their service delivery objectives.

There is a heavy burden of cervical cancer in China. Although the Chinese government provides free cervical cancer screening for rural women aged 35 to 59 years, the screening rate remains low even in the more developed regions of eastern China. This study aimed to assess knowledge and attitudes about cervical cancer and its screening among rural women aged 30 to 65 years in eastern China. A cross-sectional study was conducted in four counties of Jining Prefecture in Shandong Province during August 2015. In total, 420 rural women were randomly recruited. Each woman participated in a face-to-face interview in which a questionnaire was administered by a trained interviewer. A total of 405 rural women (mean age 49 years old) were included in the final study. Among them, 210 (51.9%) participants had high knowledge levels. An overwhelming majority, 389 (96.0%) expressed positive attitudes, whilst only 258 (63.7%) had undergone screening for cervical cancer. Related knowledge was higher amongst the screened group relative to the unscreened group. Age, education and income were significantly associated with a higher knowledge level. Education was the only significant factor associated with a positive attitude. In addition, women who were older, or who had received a formal education were more likely to participate in cervical cancer screening. The knowledge of cervical cancer among rural women in eastern China was found to be poor, and the screening uptake was not high albeit a free cervical cancer screening program was provided. Government led initiatives to improve public awareness, knowledge, and participation in cervical cancer screening programs would likely be highly beneficial in reducing cervical cancer incidence and mortality for rural women. ; Tongtong Liu, Shunping Li, Julie Ratcliffe and Gang Chen

AbstractWe study market segmentation in China's stock markets, in which local firms issue two classes of shares: class A shares available only to Chinese citizens and class B shares available only to foreign citizens. Significant stock price discounts are documented for class B shares. We find that the price difference is primarily due to illiquid B‐share markets. Relatively illiquid B‐share stocks have a higher expected return and are priced lower to compensate investors for increased trading costs. However, between the two classes of shares, B‐share prices tend to move more closely with market fundamentals than do A‐share prices. Therefore, we find A‐share premiums rather than B‐share discounts in China's markets.JEL classification: G15

Abstract The outbreak of COVID-19 pandemic has resulted in a global economic recession but little is known about its impact on the informal economy including peer-to-peer rental market. Against this backdrop, this study assessed the financial loss of Airbnb listings and its hosts in Sydney from January to March 2020. Findings show that the pandemic resulted in 70% income loss for Airbnb hosts with hosts suffering eight times higher than the Airbnb platform itself. However, like other gig workers and freelancers, many Airbnb hosts are not qualified to claim the financial aids from the government in Australia. Our study shows the vulnerability of the sharing economy during a time of crisis. It contributes empirical evidence to the widening public debate on the sustainability and the sharing economy but most importantly, raises concerns over the sharing economy's contribution to a resilient society and economy.