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Henan area is climatologically situated in the transition between northern and southern China and the transition is reported to be highly sensitive to climate changes during the Holocene. To better understand the Holocene climatic and environmental changes in Henan area where high-quality data are lacking, this paper first reviewed those published palaeoenvironmental records in attempt to provide a low-resolution framework of the Holocene environmental changes in Henan area, and then synthesized the moisture proxy records from the surrounding areas in attempt to define a high-resolution trend of the Holocene moisture variation for our target site (i.e., Zhengzhou within Henan area). Two major conclusions can be drawn. First, the high-resolution Holocene moisture curve for our target site well follows the general moisture trend of China and the curve is well corroborated by two recently-reported data sets: one from Mangshan loess-palaeosol sequence and another from Laomu-Dongshiya Cave. Second, our synthesis supports an earlier notion stating that the "Holocene Moisture Optimum" in China was a delayed response to the oceanic "Holocene Thermal Optimum". The latter might in turn be a delayed response to the summer insolation peak. [ABSTRACT FROM AUTHOR]

Objective: To reduce the danger for firefighters and ensure the safety of firefighters as much as possible, based on the back propagation neural network (BPNN) the fire sensor multi-sensor information fusion detection system is investigated. Method: According to previous studies, the information sources and information processing methods for the design of this study are first explained. Then, the basic structure and flowchart of the research object in this study are designed. Based on the structure diagram and flowchart, the BPNN is selected to fuse the feature layers in this study, and the fuzzy control is selected to fuse the decision layers in this study. The multi-sensor information fusion detection system collects information for the sensors first, processes the collected information, and sends it to the processor of the robot. The processor analyzes and processes the received signal, and transmits the obtained information to the control terminal through the wireless communication system. Results: Through the tests in this study, it is found that when the number of hidden layer nodes of the BPNN is 7, the optimal training result is obtained. On this basis, the test of BPNN in this study is performed. The test results show that after 127 iterations, the error of the BPNN reaches the lowest target value, indicating that the BPNN achieves an excellent level of accuracy. The trained BPNN has a running time of 0.0276 s and a mean square error of 0.0013. The smaller the mean square error value is, the higher the accuracy of the BPNN is, which shows that the BPNN meets the high precision requirements of this study. Conclusion: The research on the multi-sensor information fusion detection system of fire robots in this study can provide theoretical support for the research on forest fire detection in China. Since the proposed BPNN-based robot is applied to the inspection and processing of forest remaining fire, the results are applicable to the forests of various countries, with a wide range of applications. [ABSTRACT FROM AUTHOR]

Many coastal cities reclaim land from the sea to meet the rapidly growing demand for land caused by population growth and economic development. Settlement in reclaimed land may delay construction and even damage infrastructures, so accurately predicting the settlement over reclaimed areas is important. However, the limited settlement observation and ambiguous final settlement estimation affect accurate settlement prediction in traditional methods. This study proposes a new strategy to solve these problems by using the Multitemporal Interferometric Synthetic Aperture Radar (MT-InSAR) method and takes the Xiamen Xiang'an International Airport, built on reclaimed land, as an example. The MT-InSAR is adopted to process the Sentinel-1 images to obtain the settlement history of the study area. The results show that settlement mainly occurs in the reclaimed areas, with the maximum average settlement rate exceeding 40 mm/y. We use the statistical properties of curve fitting to choose the best curve model from several candidate curve models to predict the settlement time series. The Asaoka method is used to identify the critical state between settlement and stability. We predict the consolidation time of the whole study area and reveal that the deformation rate is positively correlated with the consolidation time. The maximum remaining settlement time is over ten years since 24 December 2019. Therefore, manual compaction operations can be carried out to speed up settlement in the areas that need a long time to consolidate. The proposed method can be used to predict the settlement of similar reclaimed areas, and the predicted results can provide a reference for engineering construction. [ABSTRACT FROM AUTHOR]

The southeastern Lixiahe Plain (SELP) is the site of the only identified Neolithic human settlements in the eastern Northern Jiangsu Plain, East China, and it also represents the junction of the Lixiahe Plain (LP), the Northern Jiangsu coastal Plain, and the Yangtze River Delta northern flank Plain. Based on previous studies and lithology, marine micropaleontological analysis, and the results of AMS 14C dating of three sets of strata from the Neolithic "ruins area", we discussed the timings and mechanisms and the regional significance of the Early–Middle Holocene marine–terrestrial transitions in the SELP as well as the origins of its Neolithic culture. A rare phenomenon is identified in the study: Under the background of the rapid sea-level rise in the Early Holocene, the eastern part of the area accreted from the marine environment to a coastal tidal flat at approximately 8000 a BP (8900 cal a BP). This accretion was due to the obstruction of the palaeogeomorphic uplift belts to the east and south of the LP and the convergence and accumulation of sediments caused by the radiating tidal current field in the South Yellow Sea. The western part transformed into a swamp environment at approximately 5500 a BP (6300 cal a BP) due to the formation of the Yangtze River north coastal sand bank during the Early to Middle Holocene. As the first new land formed in the study area during the Holocene, the marine–terrestrial changes of the SELP formed the boundaries of the spatial evolution of the three plains, thus limiting their respective evolution range. As the archaeological evidence necessary to build a complete evidence chain is lacking, palaeogeography and traffic problems limit our current understanding on the Neolithic cultural origins in the SELP, which may be the future direction of research efforts. [ABSTRACT FROM AUTHOR]

The Thiessen polygon concept was applied to analyze how Neolithic sites were gathered and the features of agriculture, living environment and transportation in the Huaibei Plain, Anhui Province, East China, in the Shishanzi cultural period (8.0–6.5 ka BP), Dawenkou cultural period (6.5–4.5 ka BP), and Longshan cultural period (4.5–4.0 ka BP). The Thiessen polygon analysis method was effective in determining the settlement center of the region and helped to confer the complex relationships among agriculture, the living environment and transportation during the Neolithic Age. From the Shishanzi cultural period to the Longshan cultural period, a growing number of small polygons showed enhancement in the degree of gathering and cultural communication. In the Dawenkou and Longshan cultural periods, the central part of Huaibei Plain was the settlement center and the distance from the center of each Thiessen polygon to its edges was decreasing. This indicates that the ancients' dependence on agriculture and development conditions increased over the three cultures. The development of Neolithic cultures was also affected by the environmental changes in the Huaibei Plain. From the Shishanzi cultural period to the Longshan cultural period, the climate tended to be dry, and the area of marsh decreased. However, there was little change in temperature, which was beneficial to the ancients' lives and production. Not only did cultural sites and small polygons increase constantly, but groups of sites and settlement centers also appeared in the central part of plain and areas along the main stream of the Huai River. The Neolithic culture developed vigorously, and the abilities of ancients to adapt to environment and transform nature gradually improved. The NW to SE direction of the small polygons' distribution suggests the control of the ancient rivers on transportation in the Huaibei Plain. [ABSTRACT FROM AUTHOR]