A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

Most existing treatments for origami-folding simulations have focused on regular-shaped configurations.This article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities nowadays.To better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between planes.Based on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five candidates.When the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami configuration.When the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

Numerical simulation of groundwater under complex karst conditions and the prediction of roadway gushing in a coal mine:a case study in the Guang'an Longtan Reservoir in Sichuan Province, China

Numerical simulation of groundwater in karst areas has long been restricted by the difficulty of generalizing the hydrogeological conditions of reservoirs and of determining the relevant parameters due to the anisotropy and discontinuity of the karst water-bearing media in these areas. In this study, we used the Guang'an Longtan Coal mine in Sichuan as an example, and generalized the complex hydrogeological conditions in the reservoir area. A finite element numerical flow model was used to simulate current and future scenarios of roadway gushing at the bottom of the coal mine at pile number 1 + 700 m. The results show that the roadway section corresponding to valleys has a gushing quantity of 4323.8–4551.25 m^3/d before impoundment. Modeled water inflow after impoundment increased to 1.6 times the water inflow before impoundment, which threatens the impoundment as well as the roadway's normal operation. Therefore, roadway processing measures are needed to guarantee the safety of the impoundment and of the mining operation.

Economic Effects of China’s Import Expansion Strategy

Since 2018,China has enacted a string of policy initiatives to increase imports.To quantify this import expansion strategy’s economic effects,we created a large numerical general equilibrium model and quantitatively simulated the economic effects of the reductions of tariff and non-tariff barriers on China and other economies.Our simulation results show that overall,China’s import expansion strategy benefited both itself and others and contributed to employment,welfare,and trade growth in China and the rest of the world.In relative terms,however,China’s import expansion strategy benefited other countries more than it did itself and contributed more to the growth of the world economy.Additionally,the import expansion strategy may effectively promote China’s trade balance,and the trade equilibrium effect driven by the reduction of non-tariff barriers is more significant than that of tariff barriers.Furthermore,regarding the self-benefiting effects of import expansion,the effects of nontariff measures are significantly greater than those of tariff measures,and this result has policy implications for China’s import expansion strategy going forward.

Study on the mesoscale eddies around the Ryukyu Islands

Results of the Ocean General Circulation Model for the Earth Simulator（OFES） from January 1977 to December2006 are used to investigate mesoscale eddies near the Ryukyu Islands. The results show that：（1） Larger eddies are mainly east of Taiwan, above the Ryukyu Trench and south of the Shikoku Island. These three sea areas are all in the vicinity of the Ryukyu Current.（2） Eddies in the area of the Ryukyu Current are mainly anticyclonic, and conducive to that current. The transport of water east of the Ryukyu Islands is mainly toward the northeast.（3）The Ryukyu Current is significantly affected by the eddies. The lower the latitude, the greater these effects.However, the Kuroshio is relatively stable, and the effect of mesoscale eddies is not significant.（4） A warm eddy south of the Shikoku Island break away from the Kuroshio and move southwest, and is clearly affected by the Ryukyu Current and Kuroshio. Relationships between the mesoscale eddies, Kuroshio meanders, and Ryukyu Current are discussed.

General Simulated Annealing

Simulated annealing is a new kind of random search methods developed in recent years.it can also be considered as an extension to the classical hill-climbing method in AI——probabilistic hill-cimbing.One of its most important features is its global convergence.The convergence of simulated annealing algorithm is determined by state generating probability,state accepting probability,and temperature decreasing rate.This paper gives a generalized simulated annealing algorithm with dynamic generating and accepting probabilities.The paper also shows that the generating and accepting probabilities can adopt many different kinds of distributions while the global convergence is guaranteed.

NUMERICAL SIMULATIONS OF HEATING ANOMALY EFFECTS OF TIBETAN PLATEAU ON CIRCULATION IN SUMMER

A 5-layer numerical model with p-σ incorporated coordinate system and primitive equations is used to simulate the effects of heating anomaly at and over the Tibetan(Qinghai-Xizang)Plateau on the circulations in East Asia in sum- mer,The model is described briefly in the text and the results are analysed in somewhat detail.Results show that the sur- face albedo,the drag coefficient,the evaporation rate and the ground temperature all have large influences on the circula- tion near the Plateau and in East Asia.When the heating at the surface increases,the Tibetan high in the upper troposphere intensifies,too.Its area enlarges and its axis tilts to northwest.The upper tropical easterly increase and shifts to north.The southwesterly in the lower troposphere,in consistence,also increases.The cross-equatorial low-lev- el currents along Somali and South India are influenced to increase their speeds while those over North Australia de- crease.The land low over the Asian Continent deepens.Meanwhile the upward motions over the land of east China and over the Indo-China Peninsula intensify and therefore the precipitation over those areas increases.However,along the coastal area of China the upward motions and therefore the precipitation decrease. Atmospheric heat source anomaly has large influence on the circulation,too.Simulated results indicate that heat source anomaly in the lower atmosphere over the Plateau influences the intensity and the position of the monsoon circu- lation while that in the upper atmosphere only affects the intensity.The heating status over the Plateau has slight influ- ence on the westerly jet,north of the Plateau,while it has strong effect on the subtropical jet at the mid and low latitudes.