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An accurate assessment of the harmonious relationship between human beings and water resources is central to conducting the comprehensive management of water resources. The human-water relationship in the “Belt and Road” region is complex, but there is a lack of systematic quantitative research. An inadequate understanding of the human-water relationship hinders decision-makers in recognizing water management priorities. To fill this gap, this paper first selects six criteria for human-water harmony from the perspectives of a humanistic system and a water system. Based on these criteria, representative indexes were selected, and the harmony degree equation was used to calculate the degree of human-water harmony in 43 countries along the “Belt and Road” in 2002, 2007, 2012 and 2017. The results revealed that human-water harmony mainly exhibited a high rate of change in developing countries, while harmony was relatively stable in developed countries and generally higher than that in developing countries. At the same time, countries in the “Belt and Road” region had different human-water relationship problems, and it was necessary to solve these problems according to their national conditions. This study can be used by countries to propel themselves out of their unique situation and understand the human-water relationship from an overall perspective by conducting a comparative analysis of different countries at the national scale. These results can provide a reference for solving the harmonious development problem of the human-water relationship in countries along the “Belt and Road”.

City is an important foundation for human development. Natural disasters, whose impact on cities was influenced by disaster risk, urban vulnerability and resistance, have always posed serious threats to human development. It is important to identify the key factors in urban disaster preventing and urban securing to reduce the losses of disasters and ensure the urban safety. However, it is difficult to assess the urban safety comprehensively, as the characteristics of disasters and cities varied a lot, resulting in the limited efficiency of urban disaster prevention and management. As a result, we built an index system to improve the urban safety assessment method. By taking six types of urban disasters (urban flood and waterlogging, drought, low temperature, sandstorm, earthquake, and rockfall, landslide and debris flow disasters) into consideration, based on the open access data and the convenient methods to calculate weights and indices, this evaluation system is of applicability and simplicity, and it can overcome the low efficiency shortcoming of the current assessment methods. The index system was then applied to 596 cities in the mainland of China to validate its effectiveness and accuracy and understand the situation of urban safety of China. The interaction mechanisms among the three characteristics of urban disasters (disaster risk, urban vulnerability and resistance) were analysed qualitatively and quantitatively, and the ‘compensate effect’ between urban vulnerability and resistance was found. According to the result of the urban safety assessment, the safety situations of most cities in China were not satisfactory, but there was great potential to improve them. Since the major natural disasters and safety degrees varied in different cities, these Chinese mainland cities were classified into six different regions based on our results, and the key points of disaster management in each region were pointed out, in order to help the government to promote Chinese cities’ safety.

The consumption of raw oyster has been linked to numerous foodborne gastroenteritis outbreaks caused by norovirus (NoV) in different countries of the world, including in China. This study investigated the prevalence of NoV and contamination levels in retail oysters taken from markets in Beijing and Qingdao in China. The oysters were collected monthly from seafood markets between September 2015 and September 2016 (13 months) in both cities. The digestive glands of these oysters were dissected and NoV particles were extracted. Viral RNA was detected using a TaqMan-based real time one-step reverse transcription-PCR (qRT-PCR) protocol. Of total 672 oyster samples assessed, 652 were considered to be valid for inclusion in the study. The prevalence of NoV was 20.71% (135/652), and this included 21.48% (29/135) of the samples that were positive for the GI strain alone, 62.96% (85/135) contained the GII strain alone and 15.56% (21/135) were mixed with GI and GII, respectively. A total of 68 NoV-positive samples were quantified by qRT-PCR and values obtained ranged from 3.55 × 103 to 1.45 × 106 genomic copies per g digestive tissue. The NoV contamination in retail oysters fluctuated with the sampling month and peaks of contamination occurred in February (49.12%) and March (55.36%) 2016, respectively. Considering some of the oysters were consumed as raw or half-cooked in China, as a risk reduction measure these oysters should be well heated prior to consumption. Furthermore, successive and region-extended monitoring in retail oysters for NoV as well as risk communication is recommended.

In this paper, a novel method based on Kernel Principle Component Analysis is proposed to extract features of radar emitter signals image of Choi-Williams distribution. Then these discriminative and low dimensional features obtained were fed to the classifier designed for different radar LFM signals which is based on fuzzy Support Vector Machines (FSVMs). In simulation experiments, the classifier attains over 90% overall average correct classification rate. Experimental results show that the proposed FSVM classifier is efficient for different complex radar signals detection and classification.

In this paper, the modern radar signal waveforms are introduced. For improving the detection capability and reducing the probability of interception, the more complex signal waveforms are applied in the modern radar system. Some basic principles are provided in the design of the LPI signal waveforms. Some novel waveforms with complex modulation are introduced. The WVD-Hough transform are used to analysis the performance of novel radar signals. Experimental results show that the waveforms with combined modulation are efficient for radar anti-reconnaissance design in modern electronic warfare environment. (5 pages)