Search

With the outbreak of COVID-19 in late 2019, people’s awareness of actively searching for health information has been growing. Coupled with the promotion of “Internet + medical and health,” social media, as an important platform for health information dissemination, has become one of the important information sources for users to obtain health information. However, health information seeking behavior in public health emergencies are quite different from those in daily life. Therefore, the research question of this paper is to explore the influencing factors of health information seeking behavior of social media users in the context of COVID-19. To this end, based on the research framework of social cognition theory, this paper selects six variables to construct a structural equation modeling, including information and platform quality, experience, social support, emotional arousal, self-efficacy, and social media users’ health information seeking behavior. The empirical study is carried out by collecting 219 valid questionnaires. The research results show that: (1) Information and platform quality, and use experience have a significant positive effect on emotional arousal; (2) Experience, social support, and emotional arousal have a significant positive effect on self-efficacy; (3) Emotional arousal and self-efficacy have a significant positive effect on social media users’ health information seeking behavior. The research provides an important theoretical reference for social media users and operators to cope with the huge demand for health information in the post-COVID-19 era.

Poverty reduction in rural areas is an important development goal concerned by the international community, but the traditional poverty-reduction methods have certain drawbacks. Social entrepreneurship, with its innovative way to solve social problems, has gradually become a new sustainable development path to solve rural poverty. Using the case study method, this paper analyzes the social entrepreneurship process of 9 enterprises and the process mechanism of solving the rural poverty problem based on the identification and development of social opportunities. Our analysis suggests that social entrepreneurship is the process of identification, development and realization of social opportunities. Multidimensional rural poverty creates different social opportunities, including social opportunities in social, economic and ecological poverty. Enterprises integrate farmers into their value chain to develop and realize social opportunities, which is a sustainable means of poverty alleviation. In theory, we propose a conceptual framework for the sustainable development of social entrepreneurship and enriches the research on the process of realizing social opportunities in social entrepreneurship. In practice, we provide a sustainable development ideas for rural areas.

Articulated steering vehicles (ASVs), with brilliant maneuverability and efficiency, are being widely applied in mining, construction, agriculture, and forestry. However, their special structures result in them having complex dynamic characteristics, but there are no reliable models for further research. This study established a simulation platform with the dynamic model of ASVs, where the subsystems of the power train, steering systems, tires, and frames were also included. The dynamic model was validated with field test data of typical working cycles, in which the focus was on longitudinal and lateral motions and the characteristics of steering and power train systems. Then, the distribution of hydraulic and drive power was revealed using the simulation platform and test data. For a load–haul–dump (LHD) vehicle with a 6 m3 capacity, the maximum power of the system was about 289 kW; the power of the motor accounted for the majority of the power at the beginning stage of loading, being about 74%, and then the hydraulic power dominated in the later stage of loading. During the transport stage, the power of the motor accounted for about 79% of the total power. Finally, the influence of the dynamic parameters on lateral and longitudinal motions was analyzed based on the validated platform.

Based on seismic and logging data, taking the downthrow fault nose of Binhai fault in Qikou Sag as the object of study, we analyzed fault characteristics, sand body distribution, fault-sand combinations and hydrocarbon accumulation to reveal the hydrocarbon enrichment law in the fault-rich area of fault depression lake basin. The results show that the Binhai Cenozoic fault nose is characterized by east-west zoning, the main part of the western fault segment is simple in structure, whereas the broom-shaped faults in the eastern segment are complex in structure, including several groups of faults. The difference of fault evolution controls the spatial distribution of sand bodies. The sand bodies are in continuous large pieces in the downthrow fault trough belt along the Gangdong Fault in the middle segment of the fault nose, forming consequent fault-sand combination; whereas the fault activity period of the eastern part of the fault nose was later, and the sand bodies controlled by paleogeomorphology are distributed in multi-phase north-south finger-shaped pattern, forming vertical fault-sand combination pattern matching with the fault. The configuration between faults and sand bodies, and oil sources and caprocks determine the vertical conductivity, plane distribution and vertical distribution of oil and gas. Two oil and gas accumulation modes, i.e. single main fault hydrocarbon supply–fault sand consequent matching–oil accumulation in multi-layers stereoscopically and fault system transportation–fault sand vertical matching–oil accumulation in banded overlapping layers occur in the middle and eastern segments of the fault nose respectively, and they control the difference of oil and gas distribution and enrichment degree in the Binhai fault nose. Key words: Bohai Bay Basin, Qikou Sag, Binhai fault nose, sandstone development mechanism, fault-sand combination, oil and gas accumulation, reservoir control mechanism