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1. chinaXiv:202105.00070 [pdf]

Copula熵:理论和应用

马健
Subjects: Statistics >> Mathematical Statistics
Subjects: Computer Science >> Computer Application Technology
Subjects: Information Science and Systems Science >> Basic Disciplines of Information Science and Systems Science

统计独立性是统计学和机器学习领域的基础性概念,如何表示和度量统计独立性是该领域的基本问题。Copula理论提供了统计相关性表示的理论工具,而Copula熵理论则给出了度量统计独立性的概念工具。本文综述了Copula熵的理论和应用,概述了其基本概念和定理,以及估计方法。介绍了Copula熵研究的最新进展,包括其在统计学四个基本问题(结构学习、关联发现、变量选择和时序因果发现等)上的理论应用。讨论了四个理论应用之间的关系,以及其对应的深层次的相关性和因果性概念之间的联系,并将Copula熵的(条件)独立性度量框架与基于核函数和距离的相关性度量框架进行了对比。简述了Copula熵在水文学、环境气象学、生态学、认知神经学、系统生物学、老年医学、公共卫生学,以及能源工程、制造工程和可靠性工程等领域的实际应用。

submitted time 2021-08-19 Hits7686Downloads953 Comment 0

2. chinaXiv:202105.00090 [pdf]

基于深度学习神经网络的电池分容阶段容量预测的方法

孙瑜
Subjects: Computer Science >> Computer Application Technology

本文提出了一个使用深度学习方法预测锂离子电池分容工序的容量的解决方案。该方案从化成和分容工序中提取部分工步的物理观测值记录作为特征,训练了一个深度神经网络(Deep Neural Network, DNN)实现了电池容量的精准预测。据测试,该模型预测的电池容量与真实值相比,平均百分比绝对误差(Mean Absolute Percentage Error, MAPE)仅为0.78%。将该模型与生产线结合,可以大大缩减生产时间与能耗,降低电池生产成本。

submitted time 2021-05-29 Hits4685Downloads370 Comment 0

3. chinaXiv:202105.00077 [pdf]

二维光学刺激下的视觉感知定律

祝锐; 刘玉红; 王体春; 陈龙聪; 谢正祥
Subjects: Computer Science >> Computer Application Technology
Subjects: Engineering and technical science >> Optical Engineering

人类对刺激量的感知分为数量感知和质量感知。无论是韦伯-费克纳(Weber-Fechner)的对数感觉定律还是史蒂文斯(Stevens)的幂函数感觉定律,都是关于感觉量与一维亮度刺激之间定量关系的定律。图像属于具有二维亮度分布特征的刺激量。本文研究的是二维亮度刺激的质量的感知,即二维亮度刺激质量好坏程度的感知。好坏程度是一个模糊的心理学概念,因此我们需要用模糊数学的方法来量化图像视觉感知质量的好坏程度,即建立一个模糊隶属函数PQ来定量表示图像视觉质量的好与坏的程度。

submitted time 2021-05-24 Hits5176Downloads502 Comment 0

4. chinaXiv:202009.00125 [pdf]

Small Private Online Judge: A New Tool for Empirical Education Research

祝云篪; 赵作翰; 童澄达; 夏小俊
Subjects: Computer Science >> Computer Application Technology

This paper puts forward the concept of Small Private Online Judge (SPOJ). Compared with Massive Open Online Judge (MOOJ), SPOJ has advantages in structured data acquisition of students' virtual behavior for its specific function and tight coupling with the classroom. SPOJ-based empirical education research can be conducted within "Acquisition-Analysis-Application" (3A) Framework. The case study of a SPOJ program clarifies the standard pattern of SPOJ-based 3A research and highlights the emergence of education-intelligence concept. The challenges of SPOJ-based empirical education research and implications of SPOJ are also discussed.

submitted time 2020-09-30 Hits30178Downloads5263 Comment 0

5. chinaXiv:202008.00091 [pdf]

Better Than Reference In Low Light Image Enhancement Conditional Re-Enhancement Networks

张雨; 遆晓光; 张斌; 季锐航; 王春晖
Subjects: Computer Science >> Computer Application Technology

Low light images suffer from severe noise, low brightness, low contrast, etc. In previous researches, many image enhancement methods have been proposed, but few methods can deal with these problems simultaneously. In this paper, to solve these problems simultaneously, we propose a low light image enhancement method that can combined with supervised learning and previous HSV (Hue, Saturation, Value) or Retinex model based image enhancement methods. First, we analyse the relationship between the HSV color space and the Retinex theory, and show that the V channel (V channel in HSV color space, equals the maximum channel in RGB color space) of the enhanced image can well represent the contrast and brightness enhancement process. Then, a data-driven conditional re-enhancement network (denoted as CRENet) is proposed. The network takes low light images as input and the enhanced V channel as condition, then it can re-enhance the contrast and brightness of the low light image and at the same time reduce noise and color distortion. It should be noted that during the training process, any paired images with different exposure time can be used for training, and there is no need to carefully select the supervised images which will save a lot. In addition, it takes less than 20 ms to process a color image with the resolution 400*600 on a 2080Ti GPU. Finally, some comparative experiments are implemented to prove the effectiveness of the method. The results show that the method proposed in this paper can significantly improve the quality of the enhanced image, and by combining with other image contrast enhancement methods, the final enhancement result can even be better than the reference image in contrast and brightness. (Code will be available at https://github.com/hitzhangyu/image-enhancement-with-denoise)

submitted time 2020-08-26 Hits10818Downloads966 Comment 0

6. chinaXiv:202007.00035 [pdf]

PandaDB:一种面向异构数据的智能融合管理系统

沈志宏; 赵子豪; 王华进; 刘忠新; 胡川; 周园春
Subjects: Computer Science >> Computer Application Technology

随着大数据应用的不断深入,大规模结构化、非结构化数据带来的异构数据的融合管理、关联计算和即席查询需求日益突出。现有异构数据融合管理技术与系统存在着数据模型表示能力弱、查询执行实时性差等问题。本文提出了适用于结构化、非结构化数据融合管理和语义计算的智能属性图模型,并定义了相关属性操作符和查询语法。基于该模型实现了异构数据融合管理系统PandaDB,并详细介绍了PandaDB的总体架构、存储机制、查询机制、属性协存、AI算法调度和分布式架构。测试实验和案例证明,PandaDB的协存机制和分布式架构具备较好的性能加速效果,并可应用在关联数据发布、个人相册管理、学术图谱实体消歧等融合数据智能管理的场景。

submitted time 2020-07-20 Hits4397Downloads1219 Comment 0

7. chinaXiv:202004.00026 [pdf]

Learning an Adaptive Model for Extreme Low-light Raw Image Processing

付清旭; 遆晓光; 张雨1
Subjects: Computer Science >> Computer Application Technology

Low-light images suffer from severe noise and low illumination. Current deep learning models that are trained with real-world images have excellent noise reduction, but a ratio parameter must be chosen manually to complete the enhancement pipeline. In this work, we propose an adaptive low-light raw image enhancement network to avoid parameter-handcrafting and to improve image quality. The proposed method can be divided into two sub-models: Brightness Prediction (BP) and Exposure Shifting (ES). The former is designed to control the brightness of the resulting image by estimating a guideline exposure time t 1 . The latter learns to approximate an exposure-shifting operator ES, converting a low-light image with real exposure time t 0 to a noise-free image with guideline exposure time t 1 . Additionally, structural similarity (SSIM) loss and Image Enhancement Vector (IEV) are introduced to promote image quality, and a new Campus Image Dataset (CID) is proposed to overcome the limitations of the existing datasets and to supervise the training of the proposed model. In quantitative tests, it is shown that the proposed method has the lowest Noise Level Estimation (NLE) score compared with BM3D-based low-light algorithms, suggesting a superior denoising performance. Furthermore, those tests illustrate that the proposed method is able to adaptively control the global image brightness according to the content of the image scene. Lastly, the potential application in video processing is briefly discussed.

submitted time 2020-04-14 Hits18075Downloads1450 Comment 0

8. chinaXiv:202004.00007 [pdf]

完整的嗅觉神经通路假设及建模

张锦; 田恬恬
Subjects: Computer Science >> Computer Application Technology

嗅觉神经通路研究是嗅觉研究的基础,对脑科学研究同样具有多方面的重要意义。综合已有相关研究成果,探索了完整的嗅觉神经通路假设。该神经通路包括以嗅球层为核心的前端部分、以内嗅皮质为核心的中端部分和以齿状回为核心的后端部分。在此基础上,本文构建了完整的嗅觉神经通路结构模型,并进行了初步分析。

submitted time 2020-04-03 Hits13785Downloads1307 Comment 0

9. chinaXiv:202002.00063 [pdf]

Perspectives on Active Preventive Measures of Wuhan People against COVID-19 Epidemic at Home: A Comparative Study

zhidong,Xue; Lei,Zhao; Tailang,Yin; Yan,Fu; Zehua,Lyu; yiping,Dang; Yujiang,Zeng; Silou,Huang; Bing,Qu; Hongya,Lyu; Chen,Huang; Zhiyou,Kong; Kepei,Xu; Feipeng,Zhou; Hexun,Dong; He,Hu; Jing,Tang; Senyuan,Xue; Zhixiang,Fang; Jinxiang,Lu
Subjects: Computer Science >> Computer Application Technology

Background:The COVID-19 Epidemic emerged in Wuhan, Hubei province, China. Ever since Wuhan lockdown on January 23rd, mass quarantines were exercised on Wuhan and other epidemic areas of China. We aimed to clarify how ordinary Wuhan people defend against COVID-19 epidemic at home through the Internet survey. Methods:A questionnaire survey, consisting of 30 questions were posted on the Internet. The following aspects were investigated: household preventive measures, self-monitoring of discomfort symptoms, immunity boosting against the epidemic, frequency and reasons of outgoing and mental status of the isolated people. The questionnaire was circulated on Wechat. We marked the areas based on the surveyed network IP addresses and categorized respondents into group A(Wuhan), B(Hubei Province excluding Wuhan ), C, and D based on the epidemic severity of their areas announced by Baidu.com at 17:00 on February 8, 2020. And a comparative study was conducted to illustrate how Wuhan people took the anti-COVID-19 strategies and how efficient these preventive measures were. Findings:In terms of discomfort symptoms, Wuhan, as Group A, had the lowest asymptomatic percentages (70.2%), compared to the average 78.5% (±7%). Considering the three typical symptoms for the COVID-19, i.e., cough, fever and fatigue, Wuhan (9.67%) greatly deviated from the average (7.68%). The fatigue was the most significant factor in the deviation, exceeding the average by 1.35%. In terms of household protection measures, most people or families were able to take effective protection measures with very low frequency of going out, but the percentage of those who took this practice was obviously smaller in Wuhan and Hubei Province. From the aspect of going out, most of the people in Wuhan only went out for shopping and work, with a small number of people for social gathering. In terms of immunity boosting, compared with Group C and D, it was relatively lower in Wuhan. Overall, most people chose to enhance their immunity through regular schedule, exercise, sufficient nutrition. Only 33.44% of people in Group A did not go out, and 59.97% had to go out for living supplies, which was the highest level among the four groups. However, the percentage of people who went out for work and unnecessary activities remains the lowest while 1% of the population went out for public welfare activities, higher than other groups. Worry about the family health topped all the parameters for all the groups. Among them, Wuhan has reached a maximum of 49.61%, higher than the average level of 36.62% (± 10.69%). Mental status except for feeling bored and lonely were the highest in Wuhan. Suggestions:When the epidemic prevention and control is still in a sticky state, and Wuhan started a stricter control measure, the closed management of communities, on Feb 11, 2020, it is expected that our findings can provide some insights into the current household preventive actions and arouse more attentions of the public to some ignored preventive precautions. Unnecessary outgoing should be strictly abandoned. Regular schedule, exercises and nutrition were the top 3 measures participants would choose to enhance their own immunity system. It seems that people in Wuhan would choose nutrition and regular scheduler rather than exercises as the primary immunity-boosting ways. Exercise should be especially advocated as an effective way to enhance the immunity system. In terms of physical condition, people in Wuhan should take more active measures when symptoms occurred. The mentality is also an important aspect requiring intensive attention with the conduct of stricter control management in Wuhan while the rest groups gradually resume to work and ordinary life.

submitted time 2020-02-24 Hits23909Downloads1796 Comment 0

10. chinaXiv:202002.00015 [pdf]

人工智能在新型冠状病毒(2019-nCoV)肺炎的应用进展:需求和机遇

王永桂; 李强; 余晴; 杨水化; 徐子怡; 谢天奕; 胡珊
Subjects: Computer Science >> Computer Application Technology

[目的]探究人工智能在新型冠状病毒(2019-nCoV)的诊断、治疗和控制中的应用场景和进展,以利用人工智能为新型冠状病毒肺炎的防控提供助力。 [方法]剖析新型冠状病毒肺炎防控的技术需求,从人工智能基因测序、辅助诊断、远程专家系统、药物筛查与研制等方面,分析当前的应用进展,挖掘应用的机遇。 [结果]中国是新型冠状病毒疫情最严重的国家,存在诸多的技术短板有待科技助力,AI能在疫情防控中发挥出重要的作用,但目前处于初步阶段,缺乏经过验证的落地成果;AI辅助诊断领域重复性研发较多,其他方面研究较少。 [局限]当前应用的数据大部分来自网站报道,如有更多的学术性成果,进展的分析将更全面。 [结论]需要加大投入和调控,在数据、算法和算力共享的基础上,各方面全面展开研发。

submitted time 2020-02-15 Hits27574Downloads2740 Comment 0

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