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1. chinaXiv:202008.00091 [pdf]

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

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 Hits1444Downloads154 Comment 0

2. 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 Hits2713Downloads282 Comment 0

3. 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 Hits8902Downloads624 Comment 0

4. 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 Hits12502Downloads614 Comment 0

5. 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 Hits15736Downloads1126 Comment 0

6. 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 Hits25066Downloads1507 Comment 0

7. chinaXiv:202002.00006 [pdf]

运输,病原微生物,文化:2019-nCoV传播的动态图模型

杨晓飞; 徐暾; 贾鹏; 夏涵; 郭立; 叶凯
Subjects: Computer Science >> Computer Application Technology

自从武汉市爆发新型冠状病毒疫情以来,迅速蔓延的事态已经造成300多人死亡,一万多人感染。在中国之外有一百多起病例,影响了全球十几个国家。研究人员已经报道了冠状病毒的全基因组序列,并且正在迅速开发快速诊断试剂盒、有效的治疗方法以及预防性疫苗。最初快速增长的确诊病例触发了武汉及附近城市的封锁。世界各地的科学家尝试建立数学模型来预测未来几天内的感染病例数。但是,交通和文化习俗等主要因素尚未得到足够的权衡。我们的模型并不是为了精确预测感染病例数量,而是旨在模拟公共流行紧急情况下的动态情况以及不同影响因素的贡献。我们希望我们的模型和模拟能够为全球公共卫生机构提供更多的见解和观点信息,以便设计出更好的预防和控制解决方案。

submitted time 2020-02-03 Hits18014Downloads1402 Comment 0

8. chinaXiv:201911.00097 [pdf]

Review of Machine-Vision-Based Plant Detection Technologies for Robotic Weeding

Li,Nan; Zhang, Xiaoguang ; Zhang, Chunlong; Ge, Luzhen; He, Yong; Wu,Xinyu
Subjects: Computer Science >> Computer Application Technology

Controlling weeds with reduced reliance on herbicides is one of the main challenges to move toward a more sustainable agriculture. Robotic weeding is a thought to be a viable way to reduce the environmental loading of agrochemicals while keeping the operation efficiency high. One of the key technologies for performing robotic weeding is automatic detection of crops and weeds in fields. This paper presents an overview on various methods for detecting plants based on machine vision, mainly concentrating on two main challenges: dealing with changing light and crop/weed discrimination. To overcome the first challenge, both physical and algorithmic methods have been proposed. Physical methods can result in a more cumbersome machine while algorithmic methods are less robust. For crop/weed discrimination, deep-learning-based methods have shown obvious advantages over traditional methods based on hand-crafted features. However, traditional methods still hold some merits that can be leveraged to deep-learning-based methods. With the fast development of hardware technologies, researchers should take full advantage of advanced hardware to ease the algorithm design. In the future, the identification of crops and weeds can be more accurate and fine-grained with the support of online databases and computing resources based on the advances in artificial intelligence and communication technologies.

submitted time 2019-11-23 Hits17858Downloads915 Comment 0

9. chinaXiv:201905.00052 [pdf]

机器人自动设计初探讨:基于黑盒函数优化实现

Zhiyang Xiang
Subjects: Computer Science >> Computer Application Technology

机器人具有极大降低劳动体力需求的潜力,是目前研究热点之一。机器人设计是智力劳动密集型工业,因此机器人的自动设计方法研究具有重要的现实意义。由于现有研究中鲜有自动设计的研究,本文探讨自动设计的基本框架。将机器人设计抽象为黑盒参数优化的过程,通过物理模拟对一个特定的机器人设计进行评分,确定此次设计完成给定任务的能力。通过更改设计参数,进行完成任务能力的优化。即自动设计方法的输入是一组零件,一个需要机器人完成的任务以及一个一般是基于强化学习的机器人控制训练方法,输出是这一组零件的组合方式。由于物理模拟,或真实的实验验证在时间和劳动成本上较为昂贵,因此黑盒优化的过程须尽可能降低采样次数。本文采用贝叶斯参数优化完成设计任务。实验表明,所提出的方法可以在5次左右的模拟中完成一个两关节机器人自动设计任务。

submitted time 2019-05-05 Hits20342Downloads678 Comment 0

10. chinaXiv:201811.00043 [pdf]

区域医疗健康平台中的检查指标标准化算法研究

张佳影; 王祺; 张知行; 阮彤; 张欢欢; 何萍
Comment:CCIR2018 Accepted Paper
Subjects: Computer Science >> Computer Application Technology

由于没有完整可用的指标同义词库以进行指标映射,各家医院关于同一检验检查指标的不同称谓,已严重影响到了区域间医疗信息的互联共享,因而需要对检验检查指标进行标准化处理.这可以看作是一个实体对齐问题,但指标只有相应的取值和取值范围,难以像知识库实例匹配那般使用到属性信息,也不似实体链接那般拥有上下文信息,而且不存在一个标准知识库来提供所有指标的标准名称.该文针对以上问题,提出指标标准化算法,先根据指标字面特征进行聚类,再使用相似度特征和分块打分特征迭代地进行二分类映射.实验表明,最终的二分类映射,其F1-score可以达到85.27%,证明了该方法的有效性.

submitted time 2018-11-13 Hits1944Downloads752 Comment 0

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