Single-Index Quantile Regression with Left Truncated Data

The purpose of this paper is two fold. First, the authors investigate quantile regression(QR) estimation for single-index QR models when the response is subject to random left truncation.The random weights are introduced to deal with left truncated data and the associated iteration estimation method is proposed. The asymptotic properties for the proposed QR estimates of the index parameter and unknown link function are both obtained. Further, by combining the QR loss function and the adaptive LA...     

A new adaptive state space construction method for the mobile robot navigation

In order to solve the combinative explosion problems in a continuous and high dimensional state space, a function approximation approach is usually used to represent the state space. The normalized radial basis function （NRBF） was adopted as the local function approximator and a kind of adaptive state space construction strategy based on the NRBF （ASC-NRBF） was proposed, which enables the system to allocate appropriate number and size of the basis functions automatically. Combined with the reinforce- ment learning method, the proposed ASC-NRBF method was applied to the robot navigation problem. Simulation results illustrate the performance of the proposed method.     

Parallel Optimization of the Crystal-KMC on Tianhe-2

The Kinetic Monte Carlo(KMC) is one of the commonly used methods for simulating radiation damage of materials. Our team develops a parallel KMC software named Crystal-KMC, which supports the Embedded Atom Method(EAM) potential energy and utilizes the Message Passing Interface(MPI) technology to simulate the vacancy transition of the Copper(Cu) element under neutron radiation. To make better use of the computing power of modern supercomputers, we develop the parallel efficiency optimization model for the Crystal-KMC on Tianhe-2, to achieve a larger simulation of the damage process of materials under irradiation environment. Firstly, we analyze the performance bottleneck of the Crystal-KMC software and use the MIC offload statement to implement the operation of key modules of the software on the MIC coprocessor. We use Open MP to develop parallel optimization for the Crystal-KMC, combined with existing MPI inter-process communication optimization, finally achieving hybrid parallel optimization. The experimental results show that in the single-node CPU and MIC collaborative parallel mode, the speedup of the calculation hotspot reaches 30.1, and the speedup of the overall software reaches 7.43.     

MADDPG算法并行优先经验回放机制

多智能体深度确定性策略梯度(multi-agent deep deterministic policy gradient,MADDPG)算法是深度强化学习方法在多智能体系统(multi-agent system,MAS)领域的重要运用,为提升算法性能,提出基于并行优先经验回放机制的MADDPG算法.分析算法框架及训练方...     

核桃青皮主要活性物质及提取工艺研究进展

核桃青皮中含有多种活性物质,具有抑菌、杀虫、抗病毒等多种功效,然而其成分含量、提取工艺、检测技术存在差异。本文归纳整理了国内外与青皮主要活性物质的相关文献,综述其主要的有效成分、提取工艺、检测技术,为优化核桃青皮主要有效成分的提取工艺、进一步开发核桃青皮资源高效利用提供科学依据。     

Co-orbital restricted three-body problem and its application

The Purple Mountain Observatory of the Chinese Academy of Sciences and the Department of Astronomy, Nanjing University, cooperating with the Albert Einstein Institute in Germany, put forward a model of the planar co-orbital circular restricted three-body problem. We     

基于DFT的OFDM系统研究

在介绍OFDM系统技术背景的前提下,给出了基于DFT的OFDM系统的数学建模、分析及性能仿真.     

基于GIS技术的城镇建设用地适宜性评价研究——以嘉兴市凤桥镇为例

以GIS为主要技术平台,从建设经济性因子和自然生态因子两个方面进行城镇建设用地适宜性评价研究,探讨了评价方法与步骤,并以嘉兴市凤桥镇为案例进行实证研究.     

高等学校生态道德教育方法探析

生态危机是人类对自然态度的非合理性投射,实质上是自我价值危机.它不仅需要科学技术来解决,而且包含着强烈的道德诉求.以生态道德理念唤醒麻木的心灵,去除价值巫魅,追求诗意生存,教育将承受之重!高等学校生态道德教育尚付阙如,大学生生态道德缺失的现实都昭示了加强高校生态道德教育刻不容缓.生态道德教育的方法主要有:道德讨论法,研究性学习,体验教育等.     

高校研究生自我批判精神的弱化及重塑

由于受市场经济冲击、高校行政权力和学术权力失调以及研究生扩招等因素的影响,高校研究生的自我批判精神日趋弱化。重塑高校研究生自我批判精神的举措包括：坚守对高深知识的探究,理性应对市场经济带来的影响;放松管制,调适行政权力和学术权力的关系;着眼长远,正确定位大学的角色;理性扩招,提高研究生的培养质量。