改革开放:中国电影的艺术成就与文化表达

钟大丰在市场化进程中探索中国电影学院的追求回顾我们改革开放四十年,从中国的范围来讲,是一个不断走向商品市场开放的过程。电影的发展和市场开放的进程有着特别紧密的关系,当我们跟改革开放的总体进程结合得比较紧的时候,我们会看到电影表现出活力;当我们离开改革开放进程相对比较远的时候,它的活力就会减少,问题就会出现,改革开放这四十年并不一直是一帆风顺的。很多人对80年代的活跃局面很怀念,那个时

大型水利工程影响区水文生态系统变化及调控研究

《大型水利工程影响区水文生态系统变化及调控研究》系河南省科技攻关计划项目,编号为0224660030。本项目的研究成果：提出采用水文系统变异性研究方法、生态环境演变趋势研究方法,来量化研究大型水利工程水文生态效应;总结提出一种水量～水质～生态耦合系统“多箱模型”(Multi-box modeling method)方法,建立了水文-生态耦合系统模型;提出“基于DEM的流域分布式水文模型研制方法”;基于RS和GIS相结合技术、可持续发展思想,建立了大型水利工程影响区生态环境调控理论框架,为制定一般大型水利工程影响区生态环境调控对策提供理论依据;研究水文生态效应及调控对策;研究生态环境动态变化

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors