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The superstructure of a coastal bridge is prone to overturn or unseating under a catastrophic tsunami, which seriously affects the post-disaster emergency rescue. In this paper, we establish a safety assessment framework for the superstructure of a bridge with a box girder under a potential landslide tsunami, and apply it to an in-service box girder and Baiyun Slide Complex on the southeast coast of China. First, a meshless numerical approach called Tsunami Squares (TS) is used to predict the movement of landslides and tsunamis. Additionally, we introduce the velocity-weakening basal friction effect in the model to optimize the landslide dynamics. Second, the maximum lateral and vertical wave loads on a box girder can be estimated using the time series of the wave height and velocity in the TS model. Third, we construct a safety evaluation method for the superstructure using the reaction of the bearing as the critical index. The results indicate that the framework developed here provides instructive guidance for evaluating the safety of coastal bridge superstructures during tsunami disasters, and we discuss the influence of the basal friction effect, bridge elevation, and support type on the structural safety. [ABSTRACT FROM AUTHOR]

To explore the mixed traffic characteristics of vehicles and aircraft on the airport surface and solve the problem of real-time conflict detection at key intersections. According to the actual taxiing procedures and airport control rules in China, this paper focus on abstracting the mixed motion process of aircraft and vehicles in the maneuvering area, defining the convergent cross-safety operation scenario. To quantify the driver's attention to safety separation and the degree of conservatism in adjusting speed, the vehicle deceleration rate and acceleration rate are defined with α as the exponent. Under the same spacing, the vehicle deceleration rate is directly proportional to α, and α is named the vehicle safety sensitivity. At the same time, the rules of speed change of vehicles and aircraft will be designed, and a convergent operation model of aircraft and vehicles will be proposed. Based on real-time speed and separation dynamic assessment of safety and efficiency under different traffic strategies, the computer simulation results show that vehicle safety sensitivity and deceleration rules determine the sequence of vehicles and aircraft when they are passing through in the short term and can affect the proportion of mixed traffic flow in the long run. The safety probability of vehicles passing the intersection first is negatively correlated with vehicle safety sensitivity, while the safety probability of aircraft passing the intersection first is correlated positively with vehicle safety sensitivity. The efficiency of passing without conflict with mixed traffic has an inverse relationship with vehicle safety sensitivity. When the vehicle safety sensitivity takes the value in the interval [0.4, 0.6], a mixed traffic flow with higher safety and efficiency, better stability, and a balanced ratio of locomotives can be obtained. [ABSTRACT FROM AUTHOR]

Lithocarpus litseifolius although known as "Sweet Tea" (ST), has been traditionally accepted as a daily beverage and used as a folk medicine in southern China with little understanding of its potential toxicity. This study evaluated the safety of a water extract of ST by a subchronic toxicity study in Sprague-Dawley rats. A total of 80 rats were randomized divided into 4 groups with 10 males and 10 females in each group, treated with 2000, 1,000, 500 and 0 mg/kg body weight of ST extract by gavage for 90 days, respectively. The results of the study showed that ST extract did not induce treatment-related changes in the body and organ weight, food intake, blood hematology and serum biochemistry, urine indices, and histopathology in rats. The NOAEL of ST extract was observed to be 2000 mg/kg/day for rats of both sexes. These results indicated that ST extract was of low toxicity in the experimental conditions of the current study and had the potential for application in food-related products. [ABSTRACT FROM AUTHOR]

Dai, W. and Yu, Y., 2020. Data analysis of safety assessment and early warning for offshore platform. In: Gong, D.; Zhang, M., and Liu, R. (eds.), Advances in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 106, pp. 536–539. Coconut Creek (Florida), ISSN 0749-0208. Offshore platform is a very complex system and is affected by wind, wave, currents, and other loads for a long time. When a safety problem occurs in the offshore platform, catastrophic accidents can cause incalculable loss of life and property and can also damage the vulnerable marine ecological environment. However, the research on the safety of early warning of offshore platforms in China is still in its infancy. Therefore, by performing safety assessment and early-warning work, this paper can obtain the health status of the offshore platform timely and accurately. By studying the safety assessment and early-warning system of the offshore platform, a theoretical basis for the safe operation of offshore platform can be provided. Through the technology of safety monitoring and safety evaluation, this paper constructs the safety early-warning model of the offshore platform, which realizes the monitoring, diagnosis, control, correction, and other functions of the production activities of the offshore platform. [ABSTRACT FROM AUTHOR]

The safety condition assessment of prestressed concrete bridges is currently subject to great uncertainty due to the subjectivity of data collection and data types. This study proposes an improved evidence fusion method, improving the conventional Dempster–Shafer fusion method to reduce assessment inaccuracies caused by data uncertainty. Firstly, the uncertain analytic hierarchy process was applied to construct a three-level safety assessment model for 15 different indicators with their initial weights. Secondly, the fuzzy matter element theory was proposed to obtain basic probability assignments required for the evidence fusion. Finally, an improved evidence fusion method was proposed based on the evidence credibility and preprocessing corrections for highly conflicting evidence. In this study, a prestressed concrete bridge in eastern China was used as a case study to perform a comprehensive safety assessment and verify the effectiveness and practicality of the proposed method. The assessment results demonstrate that the improved fusion method in this study can deal with conflicting evidence better than existing fusion methods. Compared with conventional fuzzy AHP method, it has greater sensitivity to certain indicators with severe damages, which prevents those indicators from being overshadowed by other well-performing ones in the overall assessment. [ABSTRACT FROM AUTHOR]

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Road safety conditions in China have worsened following rapid urbanization and motorization. For a long time now, China has ranked first in the world in the number of road accidents and fatalities. Therefore, evaluating safety levels is essential to implementing effective countermeasures. For developing countries like China, however, assessing safety levels via crash data statistical analysis is difficult because of limitations on a short history of collecting crash data, small samples and an incomplete collection of information. To address these limitations, the method of surrogate safety analysis using the traffic conflict technique (TCT) has become a widely used evaluation procedure. On the basis of the mechanism analysis of TCT, the paper presents a conflict hazardous assessment model (CHAM) for the mixed traffic safety evaluation of urban intersections. In the proposed model, the principle of the conservation of momentum is used. CHAM is a model used for assessing safety levels from the aspects of severe conflict numbers and conflict hazardous levels (CHLs) when traffic conflicts among mixed-traffic modes occur. Factors such as the conflict type and conflict angle of different traffic modes, weight and velocity are considered and incorporated into the model through the integration of the accident collision theory and the head injury criterion (HIC) index for head hazard assessments. The calibration and validation of CHL models are also carried out using 341 intersection crash reports in Beijing from 2006 to 2008. The results show that the established CHL models have good validity. [ABSTRACT FROM AUTHOR]

Multiple lines of transgenic rice expressing insecticidal genes from the bacterium Bacillus thuringiensis ( Bt) have been developed in China, posing the prospect of increases in production with decreased application of pesticides. We explore the issues facing adoption of Bt rice for commercial production in China. A body of safety assessment work on Bt rice has shown that Bt rice poses a negligible risk to the environment and that Bt rice products are as safe as non- Bt control rice products as food. China has a relatively well-developed regulatory system for risk assessment and management of genetically modified ( GM) plants; however, decision-making regarding approval of commercial production has become politicized, and two Bt rice lines that otherwise were ready have not been allowed to enter the Chinese agricultural system. We predict that Chinese farmers would value the prospect of increased yield with decreased use of pesticide and would readily adopt production of Bt rice. That Bt rice lines may not be commercialized in the near future we attribute to social pressures, largely due to the low level of understanding and acceptance of GM crops by Chinese consumers. Hence, enhancing communication of GM crop science-related issues to the public is an important, unmet need. While the dynamics of each issue are particular to China, they typify those in many countries where adoption of GM crops has been not been rapid; hence, the assessment of these dynamics might inform resolution of these issues in other countries. [ABSTRACT FROM AUTHOR]