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A novel enhancement method for low illumination images based on microarray camera

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Applied Mathematics(A Journal of Chinese Universities) 2017年第3期32卷 313-322页

作者： ZOU Jian-cheng zheng wen-qi YANG Zhi-hui Institute of Image Processing and Pattern Recognition North China University of Technology Beijing 100144 China.

It is difficult but important to get clear information from the low illumination images. In recent years the research of the low illumination image enhancement has become a hot topic in image processing and computer vision. The Retinex algorithm is one of the most popular methods in the field and uniform illumination is necessary to enhance low illumination image quality by using this algorithm. However, for the different areas of an image with contrast brightness differences, the illumination image is not smooth and causes halo artifacts so that it cannot retain the detail information of the original images. To solve the problem, we generalize the multi-scale Retinex algorithm and propose a new enhancement method for the low illumination images based on the microarray camera. The proposed method can well make up for the deficiency of imbalanced illumination and significantly inhibit the halo artifacts as well. Experimental results show that the proposed method can get better image enhancement effect compared to the multi-scale Retinex algorithm of a single image enhancement. Advantages of the method also include that it can significantly inhibit the halo artifacts and thus retain the details of the original images, it can improve the brightness and contrast of the image as well. The newly developed method in this paper has application potential to the images captured by pad and cell phone in the low illumination environment.

关键词： low illumination microarray camera multi-scale Retinex image sharpening

Influences of solid particles on the formation of the third phase crud during solvent extraction

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Rare Metals 2007年第1期26卷 89-96页

作者： zheng qi RUAN Renman wen Jiankang SONG Yongsheng DONG qinghai WU Minglin YAO Guocheng General Research Institute for Nonferrous Metals Beijing 100088 China

The influences of solid particles in leach solution on the formation of the third phase crud during solvent extraction of copper were studied. Analyzed from the point of view of pH value and surface tension, the study results showed that the solid particle is one of the most important contributors for the formation of the third phase crud. During solvent extraction, if the pH value was greater than 2.30, the number of solid particles in the mother solution increased, in which case the possibility of forming the third phase crud could also increase, and the interface tension value might grow in pace with the quantity of the third phase crud.

关键词： solvent extraction solid particle the third phase crud surface tension

Fluorescence Properties of Porphyrin Dimers Incorporating an Anhydride Linker

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Chemical Research in Chinese Universities 2006年第6期22卷 684-687页

作者： FA Huan-bao YIN Wei zheng wen-qi LI Di SHAN Ning WANG Xing-qiao College of Chemistry Jilin University Changchun 130023 P. R. China

A preliminary study on a novel free base porphyrin dimer and a zinc prophyrin dimer by comparing their fluorescence properties with those of the corresponding monomers is presented. The fluorescence intensity of the free base dimer is five times higher than that of the monomer, but the fluorescence intensity of the zinc porphyrin dimer is nearly similar to that of the zinc porphyrin monomer. The emission spectra show that energy transfer occurs between the two units.

关键词： Porphyrin dimer Zinc dimer Fluorescence property

Fluorescence and Thermostability of Nanometer Porphyrin Trimer

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Chemical Research in Chinese Universities 2006年第1期22卷 14-16页

作者： SHI Ying-yan FA Huan-bao zheng wen-qi LI Di SHAN Ning WANG Xing-qiao College of Chemistry Jilin University Changchun 130023 P. R. China Departement of Base Science Jilin Institute of Architecture and Civil Engineering Changchun 130021 R. R. China

A nanometer porphyrin trimer was firstly synthesized with 1 ,3-dibromopropane as a bridge-linked agent and the fluorescence property and thermostability were studied. The results show that the fluorescence property and thermostability of the trimer are different from those of monoporphyrin. The effects of the molecule structure on the optical property and the thermostability were also studied in detail.

关键词： Monoporphyrin Porphyrin trimer Fluorescence Thermostability

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Salt Lakes In Tibet

China's Tibet 1995年第1期6卷 42-43页

作者： zheng jinping and qi wen

ＳａｌｔＬａｋｅｓＩｎＴｉｂｅｔｂｙＺｈｅｎｇｊｉｎｐｉｎｇａｎｄＱｉＷｅｎＴｈｅＴｉｂｅｔａｎＰｌａｔｅａｕ，ｓｕｒｒｏｕｎｄｅｄｂｙｔｈｅＨｉｍａｌａｙａｓ，ＫｕｎｌｕｎａｎｄＴａｎｇｇｕｌａｍｏｕｎｔａｉｎｓ，... 详细信息

ＳａｌｔＬａｋｅｓＩｎＴｉｂｅｔｂｙＺｈｅｎｇｊｉｎｐｉｎｇａｎｄＱｉＷｅｎＴｈｅＴｉｂｅｔａｎＰｌａｔｅａｕ，ｓｕｒｒｏｕｎｄｅｄｂｙｔｈｅＨｉｍａｌａｙａｓ，ＫｕｎｌｕｎａｎｄＴａｎｇｇｕｌａｍｏｕｎｔａｉｎｓ，ｂｏａｓｔｓｍｏｒｅｌａｋｅｓｔｈ...

关键词： In Salt Lakes In Tibet

Relationship between T-cell receptor α gene polymorphisms and symptomatic differences in patients with narcolepsy type 1

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Chinese Medical Journal 2019年第15期132卷 1796-1801页

作者： Hui Ouyang Fang Han Ze-Chen Zhou qi-wen zheng Yang-Yang Wang Jun Zhang Department of Clinical Neurology Peking University People's Hospital Beijing 100044 China Department of Clinical Pulmonology Peking University People's Hospital Beijing 100044 China Department of Epidemiology and Biostatistics School of Public Health Peking University Health Science Center Beijing 100191 China

Background:Recent genome-wide association studies have identified an important role of T-cell receptor α(TRA) gene in the development of narcolepsy type ***,the role of TRA haplotype polymorphisms in the symptomatic diversity of narcolepsy remains *** study aimed to investigate whether TRA polymorphisms can influence the symptomatic diversity of ***:Totally,903 patients with narcolepsy type 1 were included in the *** were divided into different groups according to their ***,13 genotyped single nucleotide polymorphisms in the TRA were assessed for their association with symptoms of *** used the Chi-square test to determine differences in genotype frequencies in patients with ***,we identified the haplotypes and variations of the TRA and tested their association with the symptoms of narcolepsy using a logistic regression ***:According to the results of the logistic regression,TRA haplotypes TG and CT were significantly associated with auditory hallucination,with odds ratios of 1.235 (95% confidence interval [CI],1.012-1.507) and 1.236 (95% CI,1.012-1.511),respectively (P < 0.05).Contusions:The patterns of haplotype in TRA (haplotypes TG and CT) are associated with hypnagogic auditory hallucination in patients with narcolepsy type ***,further studies are needed to confirm our results and explore the underlying mechanisms.

关键词： Narcolepsy T-cell receptor α gene Symptomatic subtype Haplotype Precision medicine

Prokinetic effects of a ghrelin receptor agonist GHRP-6 in diabetic mice

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World Journal of Gastroenterology 2008年第30期14卷 4795-4799页

作者： qi zheng wen-Cai qiu Jun Yan Wei-Gang Wang Song Yu Zhi-Gang Wang Kai-Xing Ai Department of General Surgery The Affiliated Sixth Hospital of Medical School Shanghai Jiaotong University Shanghai 200233 China

AIM： To investigate the effects of a ghrelin receptor agonist GHRP-6 on delayed gastrointestinal transit in alloxan-induced diabetic mice. METHODS： A diabetic mouse model was established by intraperitoneal injection with alloxan. Mice were randomized into two main groups： normal mice and diabetic mice treated with GHRP-6 at doses of 0, 20, 50, 100 and 200 μg/kg ip. Gastric emptying （GE）, intestinal transit （IT）, and colonic transit （CT） were studied in mice after they had a phenol red meal following injection of GHRP-6. Based on the most effective GHRP-6 dosage, atropine was given at 1 mg/kg for 15 rain before the GHRP-6 injection for each measurement. The mice in each group were sacrificed 20 min later and the percentages of GE, IT, and CT were calculated. RESULTS： Percentages of GE, IT, and CT were significantly decreased in diabetic mice as compared to control mice. In the diabetic mice, GHRP-6 improved both GE and IT, but not CT. The most effective dose of GHRP-6 was 200 μg/kg and atropine blocked the prokinetic effects of GHRP-6 on GE and IT. CONCLUSION： GHRP-6 accelerates delayed GE and IT, but has no effect on CT in diabetic mice. GHRP-6 may exert its prokinetic effects via the cholinergic pathway in the enteric nervous system, and therefore, has therapeutic potential for diabetic patients with delayed upper gastrointestinal transit.

关键词： GHRP-6 Diabetes mellitus Gastric emptying Intestinal transit Colonic transit

Analysis of functional failure mode of commercial deep sub-micron SRAM induced by total dose irradiation

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Chinese Physics B 2015年第10期24卷 380-385页

作者：郑齐文崔江维周航余德昭余学峰陆妩郭旗任迪远 Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics and ChemistryChinese Academy of Sciences Xinjiang Key Laboratory of Electronic Information Material and Device University of Chinese Academy of Sciences

Functional failure mode of commercial deep sub-micron static random access memory（SRAM） induced by total dose irradiation is experimentally analyzed and verified by circuit simulation. We extensively characterize the functional failure mode of the device by testing its electrical parameters and function with test patterns covering different functional failure modes. Experimental results reveal that the functional failure mode of the device is a temporary function interruption caused by peripheral circuits being sensitive to the standby current rising. By including radiation-induced threshold shift and off-state leakage current in memory cell transistors, we simulate the influence of radiation on the functionality of the memory cell. Simulation results reveal that the memory cell is tolerant to irradiation due to its high stability, which agrees with our experimental result.

关键词： total dose irradiation static random access memory functional failure mode

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车身俯仰运动对气动升力的影响

中国公路学报 2017年第1期30卷 150-158页

作者：黄泰明谷正气陈阵文琪罗泽轩湖南大学汽车车身先进设计制造国家重点实验室湖南长沙410082 湖南理工学院机械工程学院湖南岳阳414006 湖南文理学院洞庭湖生态经济区建设与发展省级协同中心湖南常德415000

为了明确汽车车身俯仰运动对气动升力的影响,建立了某轿车车身俯仰运动模型,并采用大涡模拟对其进行了准静态及瞬态模拟分析。利用动网格技术实现了车身绕前轴中心的正弦俯仰运动,并通过稳态的1∶3模型风洞试验验证了大涡模拟法的准确... 详细信息

为了明确汽车车身俯仰运动对气动升力的影响,建立了某轿车车身俯仰运动模型,并采用大涡模拟对其进行了准静态及瞬态模拟分析。利用动网格技术实现了车身绕前轴中心的正弦俯仰运动,并通过稳态的1∶3模型风洞试验验证了大涡模拟法的准确性。从车身周围流场、车身表面压力等不同的角度对气动升力变化规律及机理进行了分析。结果表明:车身正弦俯仰运动时,瞬态气动升力也随之发生周期性变化,与准静态下气动升力的变化完全不一致,准静态模拟与试验条件下气动升力变化趋势基本一致;瞬态模拟时最大和最小气动升力系数都约为准静态模拟时的3倍;瞬态模拟时,由于流场中气流受到惯性以及黏性作用的影响,导致最大和最小气动升力系数都出现在车身接近水平位置时,与准静态模拟及试验中出现位置完全不同;车身俯仰运动时,车身上表面的压力变化相对较小,而车底板的压力变化很大,且对气动升力有着重要影响,车身从不同方向运动到水平位置时,底板后端的气动压力相差近40N;后轮胎周围的流场变化对气动升力也有重要影响,车身从不同方向运动到水平位置时,后轮罩中心截面上相同位置处和后轮胎后端表面的压力系数最大差值均约为0.4。

关键词：汽车工程气动升力大涡模拟俯仰运动瞬态模拟