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With tunnel boring machines (TBMs) widely used in tunnel construction, the adaptable adjustment of TBM operating status has become a research focus. Since the prediction of tunnel geological conditions is still challenging before excavating, the prediction of important TBM operating parameters plays an important role in the research on TBM adaptable adjustment. This paper proposes an intelligent prediction method of TBM tunneling parameters based on bidirectional gate recurrent unit incorporating attention mechanism (Bi-GRU-ATT) and selects a complete tunneling cycle to predict the tunneling parameters of the TBM complete tunneling cycle. Relying on the TBM3 bid section of Jilin Water Supply Project, 21 key parameters of the complete tunneling cycle are selected as the input features of the model to realize the prediction of four tunneling parameters in the complete driving cycle section of TBM. Compared with the Bi-GRU, GRU, and Long Short-Term Memory (LSTM) models, it can be seen that the Bi-GRU-ATT model has a goodness of fit for predicting TBM tunneling parameters above 0.92, and the average absolute percentage error is less than 1.8%. The results show that the prediction method of TBM tunneling parameters based on Bi-GRU-ATT model proposed in this paper has stronger learning and prediction capabilities. This prediction method provides a more feasible auxiliary intelligent decision-making method for TBM aided intelligent construction. [ABSTRACT FROM AUTHOR]

Jilin is an important grain producing area and heavy industry base in China. With the economic development and improvement of people's livelihood, water resource issues have been becoming increasingly prominent, Jilin Province comprehensive utilization of water resources is not efficient. The traditional method of water consumption per 10000 Yuan of output value cannot objectively reflect the water-use efficiency of different local industrial structures. Therefore, this paper builds the data envelopment analysis model based on the input-output relationship. In order to meet the requirements of data envelopment analysis model for data analysis, this paper introduces the principal component analysis method, and reduces the 16 water resources input indicators and 14 water resources output indicators of Jilin Province from 2004 to 2017 to 3 input principal components and 2 output principal components. The multi-model data envelopment analysis method is used to analyze the water-use efficiency of Jilin Province, and the results show that with the rapid economic growth, the water resources efficiency in 2010-2013 was relatively poor, there was a waste of water resources, and the management technology was backward, but with the deepening of the industrial transformation and upgrading, farming modernization and revitalizing the strategy of the old industrial base in Northeast China, the water-use efficiency and the water resources carrying capacity of Jilin Province has been improved. [ABSTRACT FROM AUTHOR]

In recent years, the main grain-producing areas in the west of Jilin have gradually concentrated in the perennial irrigation areas and supplementary irrigation areas in the north, and the stress degree of grain irrigation water resources is gradually increasing. Therefore, this paper selects the arid and semiarid area in the west of Jilin Province as the research area and compares and analyzes the modeling process and simulation accuracy of the temporal and spatial distribution of food security production and total water resources. Based on the center of gravity model, this paper studies the temporal and spatial distribution of food security production and total water resources in Western Jilin. It can be seen that after 2018, rice and wheat show a fluctuating upward trend, and their values rise from 0.612 to 0.786 and 0.356 to 0.612, respectively; the rise of corn is small, showing an inverted "U" trend, which first increases from 0.693 in 2018 to 0.701 in 2019 and then decreases to 0.671 in 2021; By comparing the precipitation statistics in different years, the inverted "U" trend of corn irrigation water efficiency may be related to the sudden increase of precipitation. The center of gravity model is used to analyze the evolution trend of the center of gravity of grain production and water resources in Western Jilin from the national and regional levels, and the spatiotemporal coupling degree of the center of gravity of grain production and water resources is explored through the two-factor center of gravity coupling situation model. [ABSTRACT FROM AUTHOR]

As an important ecosystem service, water supply is closely related to human well-being. Maintaining the balance of water supply and demand is essential in the sustainable development of a regional economy and society. Taking western Jilin, where the difference between water supply and demand is increasingly prominent, as the research object, from the perspective of land consolidation and precipitation changes, this paper analyzes the temporal and spatial changes of water resources supply and demand at the regional and county scales in western Jilin from 2000 to 2018 by the InVEST model and the water resource demand model. The results show that water production in western Jilin did not change significantly before and after land consolidation. The change in planting structure made water demand increase from 3.03 billion m3 to 4.96 billion m3, which reversed the relationship between supply and demand. The impact of precipitation changes on water production is extremely significant. The annual production of water in wet years is 8.05 billion m3, and the annual water production in dry years is 1.08 billion m3. The amount of precipitation can directly change the relationship between the supply and demand of local water resources. The evolution of the water resources supply and demand pattern in western Jilin is the result of the combined effect of land consolidation and precipitation changes. Precipitation mainly affects supply, while land consolidation mainly affects demand. [ABSTRACT FROM AUTHOR]

To promote the harmonious development of human and water resources, the scarcity and ecological value of water resources should be considered in water resource allocation. In this paper, synergetic theory was applied to the process of water resource allocation, and we constructed a synergetic theory-based water resource allocation model by investigating the synergetic principle of each link of water resource allocation. The objective equation was established for determining the optimal comprehensive benefit of the composite system. Multidimensional constraint conditions were constructed from the perspective of the social benefit, economic benefit and ecological benefit of water supply, and balance equations were established. Order parameters were selected for the social, economic and ecological subsystems, and the order degrees of the three subsystems and the synergetic degrees of allocation schemes were calculated by using the fuzzy mathematics method to provide a basis for the recommendation of an optimal scheme. Finally, we proposed a multicycle iterative algorithm to realize the overall objective of "harmonious development between humans and water resources", which provides an effective calculation tool for water resource synergetic allocation. This model was applied in Jilin, and an optimal scheme was recommended on the basis of a synergetic degree analysis, which shows that the water supply of conventional water sources will be saved by an increase in the reclaimed water supply. In addition, after the implementation of an external diversion project by 2030, the amount of groundwater withdrawal will be gradually reduced, and the water deficit rate will be significantly reduced. [ABSTRACT FROM AUTHOR]

Jilin Boluo lake wetland nature reserve is located in the northwest of Changchun city; the reserve has rich biodiversity and unique wetland water resources to develop eco-tourism. This paper first analyzes the general situation of Jilin Boluo lake wetland nature reserve and its water resources, second analyzes the water-related eco-tourism resources in the reserve, and then analyzes the status quo of eco-tourism development in the reserve on this basis. Third, the status of ecological quality and water resource management in the reserve was evaluated. Finally, based on the above research, the countermeasures of water resource utilization and protection in the development of eco-tourism in the reserve are put forward. [ABSTRACT FROM AUTHOR]

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Advance grouting is an important approach to reinforce the rock mass ahead of the tunnel face in TBM tunneling. To estimate the grouting result in TBM tunneling, a test method based on seismic ahead prospecting method was proposed. To check the grouting result, the seismic ahead prospecting was applied firstly to obtain the distribution and location of adverse geologies for grouting; Then, the geological conditions was estimated again after grouting; By studying the characteristics of reflections and velocity distributions, the grouting result could be checked. Numerical simulations prove the availability: Wave field snapshots indicate the energy of reflected waves reduces after grouting; Migration results indicate that the reflections reduce or disappear after advance grouting, as well as the estimated velocity increases. Moreover, the method was successfully applied in the diversion tunnel of the water supply project from Songhua River, which reveals the grouting result well and provides important geological guidance for construction. [ABSTRACT FROM AUTHOR]