针对非均匀光照图像不能满足"视觉匹配"的问题,依据人眼视觉机制提出了非均匀光照图像二次曝光算法.首先,融合退化过程模拟模型(Degradation process simulation model,DPSM)和Retinex模型得到了非均匀光照图像的成像模型,利...针对非均匀光照图像不能满足"视觉匹配"的问题,依据人眼视觉机制提出了非均匀光照图像二次曝光算法.首先,融合退化过程模拟模型(Degradation process simulation model,DPSM)和Retinex模型得到了非均匀光照图像的成像模型,利用修正的变分Retinex求解方法,获取乘性光照图像;在人眼视觉阈值性的引导下去除加性光照图像,获取反射图像;依据视觉感光适应性对乘性光照图像进行动态范围调整,并同反射图像相乘获取全局增强结果;将全局增强结果同原始图像融合,并对低照度区域进行颜色校正,获取"视觉匹配"结果.实验证明本文算法的场景再现结果可以较好地满足"视觉匹配",性能达到或者超越了现有算法.展开更多
In this paper we show how light emitting diodes (LEDs) can be used in conjunction with existing display technologies as a means for achieving ultra-rapid visual stimulus exposure durations. We review existing rapid vi...In this paper we show how light emitting diodes (LEDs) can be used in conjunction with existing display technologies as a means for achieving ultra-rapid visual stimulus exposure durations. We review existing rapid visual display methods, and show how our apparatus overcomes the limitations inherent with each technique. Our apparatus, the LED tachistoscope, takes advantage of the fast-switching times and high-brightness capabilities of LEDs in order to present stimuli at previously unachievable durations as rapid as 1 ms. The rapid exposure durations are achieved by external LED backlight illumination of images on a liquid crystal display (LCD) after the components of the LCD have stabilized. This ensures that stimulus onset and offset are discrete. Furthermore, the fast-switching of the LEDs enables stimuli to be revealed for very rapid durations. The paper also describes studies in which the LED tachistoscope has already been applied, and offers suggestions for other possible applications. Interestingly, in our studies we show that the human visual system is very adept at extracting information with only very minimal stimulus exposure durations. Such studies have not been possible with existing display equipment. The LED tachistoscope opens up avenues for a variety of psychological and physiological experiments and provides a means for revealing the limits of human visual perception.展开更多
A growing number of studies have shown that impaired visibility caused by particulate matter pollution influences emotional wellbeing.However,evidence is still scant on how this effect varies across individuals and ov...A growing number of studies have shown that impaired visibility caused by particulate matter pollution influences emotional wellbeing.However,evidence is still scant on how this effect varies across individuals and over repetitive visual exposure in a controlled environment.Herein,we designed a lab-based experiment(41 subjects,6 blocks)where participants were presented with real-scene images of 12 different PM_(2.5) concentrations in each block.Emotional valence(negative to positive)and arousal(calm to excited)were self-rated by participants per image,and the response time for each rating was recorded.We find that as pollution level increases from 10 to 260µg/m3,valence scores decrease,whereas arousal scores decline first and then bounce back,following a U-shaped trend.When air quality deteriorates,individual variability decreases in hedonic valence but increases in arousal.Over blocks,repetitive visual exposure increases valence at a moderate pollution level but aggravates negative emotions in severely polluted conditions(>150µg/m3).Finally,we find females,people who are slow in making responses,and those who are highly aroused by clean air tend to express more negative responses(so-called negativity bias)to ambient pollution than their respective counterparts.These results provide deeper insights into individual-level emotional responses to dirty air in a controlled environment.Although the findings in our pilot study should only be directly applied to the conditions assessed herein,we introduce a framework that can be replicated in different regions to assess the impact of air pollution on local emotional wellbeing.展开更多
目的通过文献计量分析,系统了解苯中毒的研究情况,了解研究趋势和热点。方法于2020年8月,选择美国国家医学图书馆文献数据库查询系统PubMed、美国科学引文索引(Web of Science)、中国生物医学文献服务系统(SinoMed)、中国期刊全文数据库...目的通过文献计量分析,系统了解苯中毒的研究情况,了解研究趋势和热点。方法于2020年8月,选择美国国家医学图书馆文献数据库查询系统PubMed、美国科学引文索引(Web of Science)、中国生物医学文献服务系统(SinoMed)、中国期刊全文数据库(CNKI)为检索数据库,以"苯""甲苯"等为关键词对2020年8月31日前发表的苯中毒相关文献进行检索,对文献的发表时间、数量、国家、研究机构以及发表期刊进行描述,并采用VOSviewer 1.6.10软件对文献进行关键词共现分析。结果苯中毒相关英文文献共510篇,43个国家曾发表过相关文献,其中美国发文量最大(43.92%,224/510),中国次之(11.57%,59/510);257种英文期刊发表了苯中毒相关研究成果,发表量最多的期刊是Environmental Health Perspectives(4.90%,25/510)。苯中毒相关中文文献共536篇,368家研究机构曾发表相关文献,发文量最多的机构是深圳市职业病防治院(3.36%,18/536),其次是中国疾病预防控制中心(3.17%,17/536);共有170种期刊发表相关研究成果,发表量最多的期刊是《中华劳动卫生职业病杂志》(12.13%,65/536)。关键词共现分析显示国内外文献对于苯中毒的职业暴露、血液毒性、骨髓抑制、遗传多态性等的关注度较大。结论苯中毒研究以中美两国居多,近年来研究聚焦苯中毒的血液毒性、致癌性、遗传毒性、免疫毒性相关机制的研究。展开更多
噪声是煤矿井下主要危害,对人体视觉系统的影响不容忽视。为了提高暴露在噪声环境中工人的视觉认知能力,进而减少人因事故的发生,针对视觉认知随噪声暴露时间的变化进行研究,利用Eye Link II眼动仪采集被试者的平均注视时间、平均眼跳...噪声是煤矿井下主要危害,对人体视觉系统的影响不容忽视。为了提高暴露在噪声环境中工人的视觉认知能力,进而减少人因事故的发生,针对视觉认知随噪声暴露时间的变化进行研究,利用Eye Link II眼动仪采集被试者的平均注视时间、平均眼跳幅度和眼跳次数3个眼动指标来衡量视觉认知能力随着综采工作面噪声暴露时间的变化。结果表明：1）噪声能够使视觉注意力下降,对视觉认知效率的影响不显著,对视觉辨识能力的影响较复杂;2）噪声在0-10 min和40-55 min时间段对视觉注意力影响较严重,在0-15 min和50-80 min时间段对视觉辨识能力影响较严重;3）被试者随时间变化出现视觉性疲劳后,噪声可轻微提高视觉认知效率和视觉辨识能力。展开更多
文摘针对非均匀光照图像不能满足"视觉匹配"的问题,依据人眼视觉机制提出了非均匀光照图像二次曝光算法.首先,融合退化过程模拟模型(Degradation process simulation model,DPSM)和Retinex模型得到了非均匀光照图像的成像模型,利用修正的变分Retinex求解方法,获取乘性光照图像;在人眼视觉阈值性的引导下去除加性光照图像,获取反射图像;依据视觉感光适应性对乘性光照图像进行动态范围调整,并同反射图像相乘获取全局增强结果;将全局增强结果同原始图像融合,并对低照度区域进行颜色校正,获取"视觉匹配"结果.实验证明本文算法的场景再现结果可以较好地满足"视觉匹配",性能达到或者超越了现有算法.
文摘In this paper we show how light emitting diodes (LEDs) can be used in conjunction with existing display technologies as a means for achieving ultra-rapid visual stimulus exposure durations. We review existing rapid visual display methods, and show how our apparatus overcomes the limitations inherent with each technique. Our apparatus, the LED tachistoscope, takes advantage of the fast-switching times and high-brightness capabilities of LEDs in order to present stimuli at previously unachievable durations as rapid as 1 ms. The rapid exposure durations are achieved by external LED backlight illumination of images on a liquid crystal display (LCD) after the components of the LCD have stabilized. This ensures that stimulus onset and offset are discrete. Furthermore, the fast-switching of the LEDs enables stimuli to be revealed for very rapid durations. The paper also describes studies in which the LED tachistoscope has already been applied, and offers suggestions for other possible applications. Interestingly, in our studies we show that the human visual system is very adept at extracting information with only very minimal stimulus exposure durations. Such studies have not been possible with existing display equipment. The LED tachistoscope opens up avenues for a variety of psychological and physiological experiments and provides a means for revealing the limits of human visual perception.
基金financially supported by the National Natural Science Foundation of China(Nos.71921003 and 72174084).
文摘A growing number of studies have shown that impaired visibility caused by particulate matter pollution influences emotional wellbeing.However,evidence is still scant on how this effect varies across individuals and over repetitive visual exposure in a controlled environment.Herein,we designed a lab-based experiment(41 subjects,6 blocks)where participants were presented with real-scene images of 12 different PM_(2.5) concentrations in each block.Emotional valence(negative to positive)and arousal(calm to excited)were self-rated by participants per image,and the response time for each rating was recorded.We find that as pollution level increases from 10 to 260µg/m3,valence scores decrease,whereas arousal scores decline first and then bounce back,following a U-shaped trend.When air quality deteriorates,individual variability decreases in hedonic valence but increases in arousal.Over blocks,repetitive visual exposure increases valence at a moderate pollution level but aggravates negative emotions in severely polluted conditions(>150µg/m3).Finally,we find females,people who are slow in making responses,and those who are highly aroused by clean air tend to express more negative responses(so-called negativity bias)to ambient pollution than their respective counterparts.These results provide deeper insights into individual-level emotional responses to dirty air in a controlled environment.Although the findings in our pilot study should only be directly applied to the conditions assessed herein,we introduce a framework that can be replicated in different regions to assess the impact of air pollution on local emotional wellbeing.
文摘目的通过文献计量分析,系统了解苯中毒的研究情况,了解研究趋势和热点。方法于2020年8月,选择美国国家医学图书馆文献数据库查询系统PubMed、美国科学引文索引(Web of Science)、中国生物医学文献服务系统(SinoMed)、中国期刊全文数据库(CNKI)为检索数据库,以"苯""甲苯"等为关键词对2020年8月31日前发表的苯中毒相关文献进行检索,对文献的发表时间、数量、国家、研究机构以及发表期刊进行描述,并采用VOSviewer 1.6.10软件对文献进行关键词共现分析。结果苯中毒相关英文文献共510篇,43个国家曾发表过相关文献,其中美国发文量最大(43.92%,224/510),中国次之(11.57%,59/510);257种英文期刊发表了苯中毒相关研究成果,发表量最多的期刊是Environmental Health Perspectives(4.90%,25/510)。苯中毒相关中文文献共536篇,368家研究机构曾发表相关文献,发文量最多的机构是深圳市职业病防治院(3.36%,18/536),其次是中国疾病预防控制中心(3.17%,17/536);共有170种期刊发表相关研究成果,发表量最多的期刊是《中华劳动卫生职业病杂志》(12.13%,65/536)。关键词共现分析显示国内外文献对于苯中毒的职业暴露、血液毒性、骨髓抑制、遗传多态性等的关注度较大。结论苯中毒研究以中美两国居多,近年来研究聚焦苯中毒的血液毒性、致癌性、遗传毒性、免疫毒性相关机制的研究。
