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The purpose of this study is to develop a stochastic finite element method (FEM) to solve the calculation precision deficiency caused by spatial variability of dam compaction quality.

The Choleski decomposition method was applied to generate constraint random field of porosity. Large-scale laboratory triaxial tests were conducted to determine the quantitative relationship between the dam compaction quality and Duncan–Chang constitutive model parameters. Based on this developed relationship, the constraint random fields of the mechanical parameters were generated. The stochastic FEM could be conducted.

When the fully random field was simulated without the restriction effect of experimental data on test pits, the spatial variabilities of both displacement and stress results were all overestimated; however, when the stochastic FEM was performed disregarding the correlation between mechanical parameters, the variabilities of vertical displacement and stress results were underestimated and variation pattern for horizontal displacement also changed. In addition, the method could produce results that are closer to the actual situation.

Although only concrete-faced rockfill dam was tested in the numerical examples, the proposed method is applicable for arbitrary types of rockfill dams.

The value of this study is that the proposed method allowed for the spatial variability of constitutive model parameters and that the applicability was confirmed by the actual project.

The purpose of this paper is to provide insights into the current practice, challenges and future development trends of intelligent compaction (IC) technology from a bibliometric perspective.

A bibliometric analysis on IC-relevant studies is presented. Through this quantitative manner, insights into the current IC research practice and development trends have been derived from the perspectives of publications and citations, spatial distribution, knowledge construction, structural variations, existing problems, and conclusions and recommendations.

Currently, IC applications are confronted with the issues of intelligent compaction measurement values (ICMVs) applicability, autonomous control, specifications and applications. To address the issues, three potential research directions are identified: a comprehensive ICMV measurement system that is designated for single layer analysis; autonomous control mechanisms with integrated management capabilities that can efficiently collaborate all stakeholders; and a standardized application workflow and the cost-benefit evaluation of IC in the context of the full life cycle.

The literature used in this paper is collected from the Web of Science. Although the database covers almost all the important publications in IC field, studies not indexed by the database are not considered.

This research quantitatively analyzes the current IC practice and development trends from the perspectives of bibliometric analysis. It provides an overview of the knowledge construction and development of IC technology. The discussions about the problems and the suggested solutions can be useful for those interested in this field.

This research establishes an evaluation index system and calculation method for the China's maritime power construction index (CMPCI). It has conducted practical tests on the progress of China's maritime power construction since the 12th–13th Five-Year Plans. This paper conducts a phased study on the construction of China's maritime power based on the CMPCI evaluation results; it expands the relevant achievements in the research field of quantitative research in China's maritime power construction. The verification results are consistent with the actual situation.

Fully reflect the guiding role of national marine policies in the new development stage, guide the transformation of China's marine management model. The CMPCI is a quantitative evaluation of the overall development level of China's maritime power construction over a certain period of time. The CMPCI in this article aims to comprehensively reflect the changes in the construction of China's maritime power, strives to cover various fields it encompasses. This study focuses on objective statistical data analysis, supplemented by multisource data, to objectively and fairly measure the level of CMPCI.

It fully reflects the highlights of marine science and technology, social democracy and strategic emerging industries. This research dynamically quantifies the trajectory of China's maritime power construction, synthetic reflecting the country's macroeconomic policy guiding function. Guiding the transformation of the marine resources utilization, marine economy development, marine scientific research and marine rights and interests maintenance and effectively serving the decision-making needs of the government.

In many cases, the external pipelines of aero-engine are subjected to random excitation. The purpose of this paper is to reduce the vibration response of the pipeline system effectively by adjusting the hoop layout.

In this paper, a spatial pipeline supported by multi-hoops is taken as the object, the methods of solution of the vibration response of the pipeline system by using pseudo excitation and hoop layouts optimization with amplitude reduction of vibration response as the goal are presented. First, the finite element model of the spatial pipeline system is presented. Then, an optimization model spatial pipeline is established. Finally, a case study is carried out to prove the rationality of the random vibration response analysis of the pipeline system. Furthermore, the proposed optimization model and genetic algorithm are applied to optimize the hoop layout.

The results show that the maximum response variance after optimization is reduced by 32.8%, which proves the rationality of the developed hoop layout optimization method.

The pseudo excitation method is used to solve the vibration response of aero-engine pipeline system, and the optimization of the hoop layout for aero-engine spatial pipelines under random excitation to reduce random vibration response is studied systematically.

In order to certify the testing of vehicle Cd on the real road can be replaced by the much simplified steady-state simulation process inside wind tunnel.

The paper opted innovative methods to verify the feasibility of using aerodynamic wind tunnel test for vehicle development purpose, including establishing the typical sinusoidal mapping function for road shapes during vehicle driving process to simplify the complexity of the road and choosing three different kinds of road spectrum amplitudes to establish the vehicle motion model, which can accurately predict the vehicle motion characteristics in the road driving process. The new approach simulates the vehicle aerodynamics on the road by taking into account the pitch angle changes during vehicle motion.

By comparing the transient drag coefficient on road with the steady-state simulated value in the conventional aerodynamic wind tunnel. This paper provides empirical insights about the flow field analysis around the vehicle on road that can verify the feasibility of using aerodynamic wind tunnel test for vehicle development purpose.

Because of establishing the typical sinusoidal mapping function for road shapes, the study results may lack generalizability. Therefore, researchers are encouraged to test the proposed propositions further.

This paper includes implications for the flow field analysis around the vehicle on road that can verify the feasibility of using aerodynamic wind tunnel test for vehicle development purpose.

This paper fulfills an identified need to use aerodynamic wind tunnel test for vehicle development purpose.

To solve the problem that the underwater vehicles is difficult to turn and exit in a small range in the face of complex marine environment such as concave and ring under the limitation of its limitation of its shape and maximum steering angle, this paper aims to propose an improved ant colony algorithm based on trap filling strategy and energy consumption constraint strategy.

Firstly, on the basis of searching the global path, the disturbed terrain was pre-filled in the complex marine environments. Based on the energy constraint strategy, the ant colony algorithm was improved to make the search path of the underwater vehicle meet the requirements of the lowest energy consumption and the shortest path in the complex obstacle environment.

The simulation results showed that the modified grid environment diagram effectively reduced the redundancy search and improved the optimization efficiency. Aiming at the problem of “the shortest distance is not the lowest energy consumption” in the traditional path optimization algorithm, the energy consumption level was reduced by 26.41% after increasing the energy consumption constraint, although the path length and the number of inflection points were slightly higher than the shortest path constraint, which was more conducive to the navigation of underwater vehicles.

The method proposed in this paper is not only suitable for trajectory planning of underwater robots but also suitable for trajectory planning of land robots.

China's economic transition is essentially the process of China's institutional changes. During the changes, the appearance of institutional innovation is not regular; instead, it is intermittent and random. The purpose of this paper is to show that the fitful appearance of institutional innovation is the root of China's economic growth and fluctuations.

This paper constructs a real business cycle (RBC) model introducing the institutional factor expressed in the quantitative form under the dynamic stochastic general equilibrium (DSGE) framework by measuring China's institutional changes quantitatively.

By comparing the characteristics of the actual economic data with those of the simulated economic data, we find that this RBC model can explain 94.44%, 66.07%, 23.46%, 21.03% and 15.45% of the cyclical fluctuations in output, investment, labor, consumption and capital, respectively.

The impulse response analysis finds that the institutional shocks have a relatively long duration, lasting about 30 years, and decline slowly over time, while technological shocks decline relatively fast, lasting approximately ten years.

The coefficient of thermal expansion (CTE) and modulus of elasticity (ME) values of mortar and stone from room temperature to cryogenic temperatures provide an experimental basis for the design of liquefied natural gas (LNG) storage tanks.

The CTE and ME of mortar and limestone were measured by resistance strain gauge testing technology at cryogenic temperatures.

The test results showed that CTE values of mortar and stone decreased with the decrease of temperature and CTE values of mortar was greater than that of stone from 0 °C to −165 °C. The ME values of mortar increased significantly at cryogenic temperatures, and less change in stone.

The material at cryogenic temperatures may continue to work in the elastic phase due to the continuous increase of elastic modulus. Therefore, the study of material in the elastic stage may be more important than in the ultimate bearing capacity stage, and it is necessary to carry out further study surrounding the deformation properties of materials at cryogenic temperatures. The CTE and ME values of mortar and stone from room temperature to cryogenic temperatures provide an experimental basis for the design of LNG storage tanks.

From the perspective of land mortgages, the purpose of this paper is to understand how farmers can be motivated to utilize environment-friendly formula fertilizers, thereby reducing the use of chemical fertilizers.

Two hypotheses are empirically tested using questionnaire responses from 714 farmers across three provinces in China to establish the relationship and to determine the role land rent plays.

This study finds that farmers who obtain land mortgages will be more willing to apply formula fertilizers in order to obtain higher value of their “own” land. This is because obtaining land mortgages can be considered as the process of titling land management rights. Farmers who have been transferred the land by verbal agreement no longer need to worry about losing it at any time. Hence, they are willing to apply formula fertilizers on their transferred land. Similarly, farmers who have been transferred the land by written contract to obtain more land mortgages will also be willing because the formula fertilizers can not only improve the quality of their transferred land, but also increase its value as collateral. This mechanism is clearer in the area where the average land rent is relatively lower.

No study has yet linked the reform of land mortgages to environmentally friendly behavior. While other studies have focused on the way access to credit changes farmer investments and spending, this particular relationship has not yet been formalized, giving this study theoretical and empirical significance.