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It is proven that there is a macro dust belt over the Northern Hemisphere, extending from northern Africa to East Asia. The dust emissions from the dust belt can reach up to around 2100 Tg/year. The Saharan desert is the largest contributor to the dust belt, accounting for about 50-60% of the total global dust. Our study indicates that Saharan dust can be transported to the upper troposphere in East Asia, contributing a substantial dust 22.88-44.94 Tg/year. It provides a new perspective on the important role of Saharan dust over East Asia. Climate variability has a significant impact on these regions, so that, it is needed to know how the aerosol particles change in the region in the context of global warming. Aiming to obtain the vertical distribution of dust aerosol and clouds, we have initiated a ground-based lidar network along the dust belt since 2018. Dust events were observed by the ground-based lidar at Tazhong station in 2021 and Ruoqiang station in 2020. We characterized the vertical distribution of these dust events. In the future, the lidar network is expected to establish 15 sites before 2024, extending from China to Northern Africa. The ground-based lidar system in the lidar network is a multi-wavelength Mie-Raman polarization lidar developed by Lanzhou University for continuously detecting water vapor, aerosols and clouds. To better assess the climate effect of dust aerosol over the region, other advanced instruments, such as sun-photometer, microwave radiometers, PM10/PM2.5 monitoring device, automatic meteorological station etc., are installed at each lidar site. The lidar network will provide continuous observational data of aerosols and clouds, which helps to better understand climate change in the region.

Development Zone A is a heterogeneous oil field with continental river-delta deposits. The channel sand body is small in scale and is dominated by straight distributary channel sand body. This type of sand body development scale is small, the drilling rate is low, generally only 17.71%, the plane shows a strong heterogeneity, the well pattern control degree is low, the sand body prediction accuracy under the current well pattern condition is low, generally only about 70%. Due to the small scale of sand body development and the development of faults, the contradiction of imperfect injection-production relationship of single sand body is prominent. In 2016, the expansion Wells of Development Zone A were put into operation successively. Based on the re-understanding of the geology of the new drilling area, the adjustment potential of development Zone A was studied, the injection-production relationship of single sand body was clarified, and the adjustment potential was implemented in combination with the results of multidisciplinary reservoir research, so as to achieve the purpose of improving the water drive control degree of the block and improving the injectionproduction relationship of sand body. After careful analysis, it was preliminatively determined that 19 Wells adjusted for injection and production system were reinjected (6 Wells were reinjected after filling holes). Internal supplementary Wells 19; One oil well was regenerated into a water well, and one water injection well was restored. A total of 41 Wells.

Horizontal well and large-scale hydraulic fracturing are the main technical means for tight gas development at present. However, tight gas reservoirs are characterized by strong heterogeneity, and different types of gas Wells have different production characteristics and pressure propagation laws. In view of the above problems, based on the physical characteristics and reservoir reconstruction evaluation of tight gas reservoir in GAS Reservoir A in Sichuan Basin, three types of reservoir hydraulic fracture models and numerical simulation models were generated by using numerical simulation method, and the production dynamic prediction and pressure wave propagation law were studied. The simulation results show that: (1) In the beginning of production, the deflated area is mainly hydraulic fracture reconstruction area, and the drainage radius of all kinds of gas Wells expands at similar speed; (2) When the drainage range is expanded in the untransformed area, the dimensionless drainage radius expansion speed of gas well is positively correlated with the reservoir physical property. The dimensionless drainage radius and drainage area of class I and II horizontal Wells are relatively faster, while that of Class III Wells is slightly slower.

Occupant behaviours in the buildings are not only random and uncertain but also related to each occupant’s habitual preference. This leads to the performance gap between actual and expected energy consumption in buildings. Therefore, accurate information and modelling with regard to occupant behaviour are important for reliable energy simulation and energy-saving optimization design. Existing studies on occupant behaviour models in office space usually focus on single-person offices or full-floor buildings, without considering the behavioural differences among offices with different occupancy. Therefore, this study established the air-conditioning usage behaviour models in offices with different occupancy based on questionnaires and measured data. The results show that occupant compromise and clustering effect will increase with the increase of occupancy. Using the established models as input, this study compared the simulation results with that under the standard schedule. The difference rate is as high as 32.19% in winter and 13.07% in the whole year. And for areas with high energy consumption in winter, the gap may be bigger.

Public health emergencies such as the COVID-19 outbreak has made all industries to reexamine the way the cities have always grown. Urban planning is no exception. Based on the analysis of the development track and phenomenon of Wuhan City, this paper puts forward the planning thinking of the development of China’s big cities. According to the study, it is urgent to study the suitable size, structure and form of big cities. The consistent practice of high-intensity development needs to stop. Urban development should pay more attention to the space that can not directly generate economic benefits.

Alertness is the state of attention by high sensory awareness. A lack of alertness is one of the main reasons of serious accidents. Traffic accidents caused by driver’s drowsy driving have a high fatality rate. This paper presents an EEG-based alertness detection system. In order to ensure the convenience and long-term wearing comfort of EEG recordings, the wearable electrode cap will be the principal choice in the future, and the selection of channels will be limited. We first built a 3-D simulated driving platform using Unity3D. Then, we perform an experiment with driving drift task. EEG signals are recorded form frontal and occipital regions. We select data segments using the driving reaction time, classify the state of alertness with a support vector machine (SVM), and select the optimal combination of channels with minimum number of channels. Our results demonstrate that alertness can be classified efficiently with one channel (PO6) at accuracy of 93.52%, with two channels (FP1+PO6) at 95.85% and with three channels (FP1+PO6+PO5 and FP1+PO6+POZ) at 96.11%.

Since formally introduced the friendly Amicable Settlement mechanism in 1987, FIDIC’ s efforts to promote and improve the alternative dispute settlement mechanism for construction work have been greatly developed. The current laws and regulations in China on alternative dispute resolution mechanisms for construction disputes are not perfect, and the newly revised “Conditions of contract for Construction” (GF2017-0201) lacks operability. It is of great significance to improve the dispute settlement mechanism by drawing on the provisions of article 20 of FIDIC (New Red Book), accumulate international experience and develop “One Belt And One Road”.