Knowledge Reasoning Method Based on Deep Transfer Reinforcement Learning:DTRLpath

In recent years,with the continuous development of deep learning and knowledge graph reasoning methods,more and more researchers have shown great interest in improving knowledge graph reasoning methods by inferring missing facts through reasoning.By searching paths on the knowledge graph and making fact and link predictions based on these paths,deep learning-based Reinforcement Learning(RL)agents can demonstrate good performance and interpretability.Therefore,deep reinforcement learning-based knowledge reasoning methods have rapidly emerged in recent years and have become a hot research topic.However,even in a small and fixed knowledge graph reasoning action space,there are still a large number of invalid actions.It often leads to the interruption of RL agents’wandering due to the selection of invalid actions,resulting in a significant decrease in the success rate of path mining.In order to improve the success rate of RL agents in the early stages of path search,this article proposes a knowledge reasoning method based on Deep Transfer Reinforcement Learning path(DTRLpath).Before supervised pre-training and retraining,a pre-task of searching for effective actions in a single step is added.The RL agent is first trained in the pre-task to improve its ability to search for effective actions.Then,the trained agent is transferred to the target reasoning task for path search training,which improves its success rate in searching for target task paths.Finally,based on the comparative experimental results on the FB15K-237 and NELL-995 datasets,it can be concluded that the proposed method significantly improves the success rate of path search and outperforms similar methods in most reasoning tasks.

超细颗粒物在非对称下呼吸道中沉积效应的数值模拟

超细颗粒物质量轻、体积小,易在空气中传播及人体呼吸系统中沉积,引起慢性疾病甚至癌症.超细颗粒物在下呼吸道沉积的相关研究较少.本研究基于Yeh模型建立第1~10级三维人体非对称支气管模型,并利用EI-Basth模型描述颗粒沉积规律,采用计算流体力学方法模拟研究不同支气管的形状和直径以及超细颗粒物的不同物性,对其沉积效应的影响及其与细颗粒物的差别.研究表明,形状变化缓和以及较大的径向流体速度差是超细颗粒物发生沉积的有利条件,曳力对超细颗粒物的作用是超细颗粒物在下呼吸道沉积的根本原因.肺部的右上叶与左下叶相比于其他部分,对超细颗粒物有一定的富集作用,在进行环境健康风险评估时应着重考虑这两个部位.不同直径超细颗粒物和细颗粒物在第1~10级支气管的沉积效应有明显区别,但它们在此部分的沉积率都低于20%.本文可为研究大气环境质量对人体肺部健康状态的影响提供理论指导和科学依据.

Excavation at Hanjing site yields evidence of early rice cultivation in the Huai River more than 8000 years ago

Through the analysis of macro-and micro-plant remains,food residues and the rice-field like features from the mid-Neolithic site of Hanjing in the Huai River region,we propose an early beginning of rice cultivation at Hanjing.The presence of non-shattering rice spikelet bases and the increasing percentages of rice phytoliths confirm the appearance of domesticated rice in the Hanjing archaeobotanical assemblage.However,as indicated by the different prediction rates of rice domestication shown by morphometric of the double-peaked Oryza-type glum cells and fish-scale decorations on the Oryza-type bulliform cells from different cultural phases before 7,000 a BP,rice cultivation was at an early stage of development.Our findings provide new and significant evidence towards the establishment of the Huai River as another important center for early rice cultivation and domestication in prehistoric China.

Evaluation and development of a predictive model for conjugate phase change heat transfer of energy storage system partially filled with porous media

The present study proposes a predictive model to explore the effect of partially filled porous media on the con-jugate heat transfer characteristic of phase change material(PCM)with interfacial coupling conditions between pure fluid region and porous region.The enthalpy-porosity method,local thermal non-equilibrium model and Darcy-Forchheimer law are comprehensively considered to describe the convective heat transfer process in porous media.The modified model is then validated by benchmark data provided by particle image velocimetry(PIV)ex-periments.The phase change behavior,heat transfer efficiency and energy storage performance are numerically investigated for different partial porous filling strategies in terms of filling content,position,height of porous foam and inclination angles of cavity.The results indicate that due to the resistance in porous region,the shear stress exerted by the main vortex(natural convection)in pure fluid region and the momentum transferred,a secondary vortex phenomenon appears in the porous region near the fluid/porous interface.Moreover,such dis-continuity of permeability and fluid-to-porous thermal conductivity results in the cusp of phase change interface at the horizontal fluid/porous boundary.Among four partial porous filling cases,the lower porous filling one has more desirable heat transfer performance,and the 3/4H lower porous filling configuration is the best solution for optimization of the latent heat thermal energy storage(LHTES)systems.For tilted cavity,the increase of inclination angle positively affects the heat transfer efficiency as well as the energy storage rate of the LHTES system,where the performance of 3/4H lower porous filling configuration is further highlighted.