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Multi-scale traffic vehicle detection based on faster R-CNN with NAS optimization and feature enrichment

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Defence technology 2021年第4期17卷 1542-1554页

作者： Ji-qing Luo Hu-sheng Fang Fa-ming Shao Yue zhong Xia hua Department of Mechanical Engineering College of Field Engineering Army Engineering University of PLA

It well known that vehicle detection is an important component of the field of object ***,the environment of vehicle detection is particularly sophisticated in practical *** is comparatively difficult to detect vehicles of various scales in traffic scene images,because the vehicles partially obscured by green belts,roadblocks or other vehicles,as well as influence of some low illumination *** this paper,we present a model based on Faster R-CNN with NAS optimization and feature enrichment to realize the effective detection of multi-scale vehicle targets in traffic ***,we proposed a Retinex-based image adaptive correction algorithm(RIAC) to enhance the traffic images in the dataset to reduce the influence of shadow and illumination,and improve the image ***,in order to improve the feature expression of the backbone network,we conducted Neural Architecture Search(NAS) on the backbone network used for feature extraction of Faster R-CNN to generate the optimal cross-layer connection to extract multi-layer features more ***,we used the object Feature Enrichment that combines the multi-layer feature information and the context information of the last layer after cross-layer connection to enrich the information of vehicle targets,and improve the robustness of the model for challenging targets such as small scale and severe *** the implementation of the model,K-means clustering algorithm was used to select the suitable anchor size for our dataset to improve the convergence speed of the *** model has been trained and tested on the UN-DETRAC dataset,and the obtained results indicate that our method has art-of-state detection performance.

关键词： Neural architecture search Feature enrichment Faster R-CNN Retinex-based image adaptive correction algorithm K-means UN-DETRAC

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番茄愈伤组织和植株耐盐性的比较研究

上海交通大学学报（农业科学版） 2001年第1期19卷 49-54页

作者：陈火英张建华钟建江潘重光上海交通大学植物科学系上海201101 华东理工大学生物反应器国家重点实验室上海200237

对 2.野生种和 4份栽培种的研究证明 ,子叶、下胚轴和叶片外植体诱导的愈伤组织对NaCl的反应是一致的。将4份野生种和 2.栽培种带有 2.一心的小苗扦插于附加不同浓度NaCl的MS培养基中 ,发现在 15 0mmolNaCl处理 10d时 ,1号、2.、3号... 详细信息

对 2.野生种和 4份栽培种的研究证明 ,子叶、下胚轴和叶片外植体诱导的愈伤组织对NaCl的反应是一致的。将4份野生种和 2.栽培种带有 2.一心的小苗扦插于附加不同浓度NaCl的MS培养基中 ,发现在 15 0mmolNaCl处理 10d时 ,1号、2.、3号和 4号材料的相对生根率分别为 6 5 .8% ,87.5 % ,86 .8%和 10 0 % ;4份野生种在附加有 75mmolNaCl的培养基上的生长优于对照 ,随着NaCl浓度的不断提高 ,株高和叶片数都表现下降 ,3号材料下降幅度最小。当NaCl浓度提高到 30 0mmol时 ,4份野生种的鲜重可达对照的 0 .90倍、1.0 7倍、1.6 0倍和 1.5 3倍 ,而 2.栽培种则为对照的 0 .5 5倍和0 .

关键词：番茄愈伤组织耐盐性生根生长比较研究体细胞突变体选择压力

Superior Ductile and High-barrier Poly(lactic acid)Films by Constructing Oriented Nanocrystals as Efficient Reinforcement of Chain Entanglement Network and Promising Barrier Wall

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Chinese Journal of Polymer science 2022年第10期40卷 1201-1212,I0009页

作者： Lin Zhou Ping-Ping Xu Shi-Hao Ni Ling Xu Hao Lin Gan-Ji zhong hua-Dong huang zhong-Ming Li Collge of Polymer science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

It is a daunting task to develop a promising strategy at an industrial scale for simultaneously ameliorating ductility and gas barrier performance of poly(lactic acid)(PLA)films in the application of green *** this work,biaxial stretching and constrained annealing were employed to prepare transparent PLA films with superior ductility and barrier *** oriented nano-sized crystals induced by biaxial stretching were developed into regularαform during constrained annealing,which could not only serve as“nano-barrier wall”to impede the diffusion and dissolution of gas molecules,but also strengthen amorphous chain entanglement network as physical crosslink to enhance *** a result,the as-prepared PLA films exhibited an outstanding comprehensive performance with a low oxygen and water vapor permeability coefficient of 0.733×10^(-14) cm^(3)·cm·cm^(-2.·s^(-1)·Pa^(-1) and 3.82.10^(-14) g·cm·cm^(-2.·s^(-1)·Pa^(-1),respectively,outstanding ductility with elongation at break of 66.0%,high yield strength of 84.2.MPa,and good transparency of more than 80%at 550 *** new insight in the relationship between microscopic amorphous and crystalline structure and macroscopic performance is conducive to alleviating the intrinsic defects of brittle and insufficient barrier PLA films without the aid of any heterogenous modifiers,facilitating their widespread commercialization in the booming sustainable packaging market.

关键词： Poly(lactic acid)films Biaxial stretching Constrained annealing Gas barrier properties Ductility

钩藤水提物Batch-2.6-羟多巴胺诱导的SH-SY5Y细胞损伤的神经保护作用(英文)

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生物化学与生物物理进展 2010年第7期37卷 769-778页

作者：石振华 XI Zhao-Wilsor 王浩关鹏于鹏常彦忠段相林赵保路河北师范大学生命科学学院石家庄050016 BioMarker Pharmaceuticals Inc.5941 Optical CourtSan JoseCA 95138USA 北京普尼公司北京100080 中国科学院生物物理研究所北京100101

以前的药理学研究表明,钩藤水溶性提取物C-MED-100TM不仅具有抗氧化活性,而且还具有很好的DNA修复和免疫功能.Batch-2.一种新的水溶性钩藤提取物,而它的自由基清除能力及神经保护作用还未见报道.首先检测了batch-2.六羟多巴胺诱导的SH... 详细信息

以前的药理学研究表明,钩藤水溶性提取物C-MED-100TM不仅具有抗氧化活性,而且还具有很好的DNA修复和免疫功能.Batch-2.一种新的水溶性钩藤提取物,而它的自由基清除能力及神经保护作用还未见报道.首先检测了batch-2.六羟多巴胺诱导的SH-SY5Y细胞损伤的神经保护作用机制,然后利用红外光谱、HPLC和分光光度技术对batch-2.组成成分进行了分析.结果表明,batch-2.有清除各种自由基的能力,尤其是对羟自由基的清除(2.mg/L的batch-2.羟自由基的清除率为60%),batch-2.剂量依赖性地抑制6-羟多巴胺诱导的细胞凋亡、脂质过氧化水平、线粒体膜电位的降低和细胞内活性氧和一氧化氮的增加.同时,batch-2.制了由6-羟多巴胺诱导的SH-SY5Y细胞内iNOS和NF-κB蛋白的上调.结果表明,batch-2.六羟多巴胺诱导的SH-SY5Y细胞损伤的神经保护作用是通过清除活性氧和一氧化氮、抑制iNOS和NF-κB表达实现的.成分分析表明,batch-2.的多酚和奎宁酸含量分别为6.43%和0.0958%.上述结果显示,batch-2.抗氧化机制部分类似于EGCG.对于帕金森病的预防,batch-2.一个潜在具有很好的神经保护作用的天然抗氧化剂.

关键词：绒毛钩藤(Uncaria tomentosa) 抗氧化剂帕金森氏病活性氧 6-羟多巴胺电子顺磁共振

内生真菌对醉马草不同生长期土壤酶活性和养分的影响

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草地学报 2024年第6期32卷 1770-1778页

作者：刘荣贵邓茂桦张瀚文郑蓉唐仲龙王超王剑峰兰州大学草种创新和草地农业生态系统全国重点实验室/兰州大学草地微生物研究中心/兰州大学草地农业科技学院甘肃兰州730020 临夏州农业科学院甘肃临夏731100

醉马草-内生真菌共生体是研究生态系统中地上与地下生物联系的独特模式,但该共生体对不同生长期土壤酶活性和养分含量的影响知之甚少。本研究采集休眠期和返青期携带内生真菌(E+)和未携带内生真菌(E-)醉马草的生境土壤,测定E+和E-醉马... 详细信息

醉马草-内生真菌共生体是研究生态系统中地上与地下生物联系的独特模式,但该共生体对不同生长期土壤酶活性和养分含量的影响知之甚少。本研究采集休眠期和返青期携带内生真菌(E+)和未携带内生真菌(E-)醉马草的生境土壤,测定E+和E-醉马草土壤酶活性和养分含量。结果表明:在休眠期和返青期,内生真菌显著增加了醉马草土壤速效磷含量,较E-醉马草分别提高34.7%和36.7%。在返青期内生真菌增加了醉马草土壤硝态氮含量,较E-醉马草提高了32.3%。此外,返青期温度升高增强了E+和E-醉马草土壤蔗糖酶和碱性磷酸酶活性,这提高了土壤N、P的有效性,为醉马草的生长返青提供基本养分。以上结果表明内生真菌通过调节土壤养分提高土壤肥力,返青期土壤酶活性和养分含量的变化保证了醉马草顺利返青。本研究为深入理解禾草-内生真菌共生体的生态学作用提供理论依据。

关键词：醉马草内生真菌土壤酶活性和养分含量休眠期和返青期

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Improvement on Conventional Load Distribution Algorithm in Hot Tandem Mills

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Journal of Iron and Steel Research International 2007年第2期14卷 36-41页

作者： LIHai-jun XU Jian-zhong WANG Guo-dong LIU Xiang-hua state key {2. of Rolling Teehnology and Automation Northeastern University Shenyang 110004 Liaoning China

Load distribution is a key technology in strip hot rolling process, which influences the coil＇s mierostrueture and performance. Currently, Newton-Raphson algorithm is applied to load distribution of hot tandem mills in many hot rolling plants and has some serious defects such as having a strict restriction on initial iterative calculation value and requiring coefficient matrix of nonlinear equations to be nonsingular. To eliminate these defects and improve the online performance of the process control computer, Newton descendent numeric algorithm is introduced to this field to widen the initial value range and a new model named error conversion algorithm is put forth to deal with special conditions when the coefficient matrix is singular. Furthermore, considering the characteristics of load distribution, a condition of strip thickness distribution abnormality and corresponding solutions are provided which ensure that rolling parameters can be calculated normally. Simulation results show that the improved algorithm has overcome the defects of the Newton-Raphson algorithm and is suitable for online application.

关键词： load distribution hot tandem mill process control computer Newton-Raphson algorithm

Organochlorine pesticides in soils from the Issyk-Kul region in the western Tian Shan Mountains,Kyrgyzstan：Implication for spatial distribution,source apportionment and ecological risk assessment

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Journal of Mountain science 2018年第7期15卷 1520-1531页

作者： LI Qian-yu WU Jing-lu ZHAO zhong-hua SAKIEV Kadyrbek state key {2. of Lake science and Environment Research Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Ecology and Environment of CentraIAsia Chinese Academy of Sciences Urumqi 830011 China university of Chinese Academy of sciences Beijing 100039 China Institute of Geology National Academy of Sciences Bishkek 720001 Kyrgyz Republic

As organchlorine pesticides(OCPs) may be an ecologic threat to mountain environments due to their tendency to deposit and accumulate in mountain regions undergoing long-range air transport, OCPs were analyzed in soils collected from an intermontane basin of the western Tian Shan Mountains, which is the UNESCO protected natural reserve of Issyk-Kul. Total OCP concentrations in the Issyk-Kul region ranged from 4.63 to 414 ng/g dw, of which two extraordinary high OCP concentrations(414 ng/g dw and 2.3 ng/g dw, respectively) influenced by an abandoned dumping site and urban sewage, respectively, were found. Principal component analysis(PCA) and correlation analysis inferred that the OCP inputs in the east of the Issyk-Kul region were mainly from local endogenous sources, and exogenous input via LRAT processes were prominent in the west and south. Additionally, the isomeric and parent substance/metabolite ratios revealed most pesticides accumulated in this region were from old usage, while DDTs had fresh input because of possibly illegal regional application and a slow degradation from the dumping site. Furthermore, ecological risk assessment revealed that no frequently adverse ecological effects were observed in the Issyk-Kul region, but potential risks on neighbouring organisms induced by p,p'-DDT and γ-HCH in dumping site and urban sewage should be considered when devising an efficient management plan to prevent secondary pollution.

关键词： Organchlorine pesticides Pesticide distribution Pesticide sources Ecological risks Issyk-Kul region Tian Shan Mountains

Effects of adsorption interferents on removal of Reactive Red 195 dye in wastewater by chitosan

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Journal of Environmental sciences 2005年第5期17卷 766-769页

作者： WEN Yue-zhong LIU Wen-qi FANG Zhao-hua LIU Wei-ping Institute of Environmental science Zhejiang University Hangzhou 310027 China Department of Environment science and Engineering Nanchang University Nanchang 330029 China

Reactive Red 195, which is an azoic anionic dye characterized by the presence of five sulfonic groups and one azoic group, is efficiently removed using chitosan. The increasing chitosan dose had a dramatic positive impact on the achieved color removal, there was approximately a linear relationship between chitosan dose and color removal of dye before color removal reach maximum. Also, the increase of dye concentration led to the increase of chitosan dosage in order to get the same color remova l.92.mg/L of chitosan dosage was sufficient to achieve complete remove of dye at initial concentration of dye at 2.0 mg/L. For the higher concentrations of dye, high dosages were necessary to reach complete color removal. On the other hand, the use of adsorption interferents（Fe^2. , Na^＋ , HCO3^- and others） can be interesting, addition of ions had effect on the color removal of Reactive Red 195. Comparing with blank, addition of chemical species approximately decreased the color removal except Na^＋ and combination of Fe^2. ＋ HCO3^- . However, comparing with Fe^2. alone and HCO3^- alone, combination of Fe^2. ＋ HCO3^- increased the color removal.

关键词： chitosan Reactive Red 195 dye coagulation color removal

Patterns and driving factors of leaf C,N,and P stoichiometry in two forest types with different stand ages in a mid-subtropical zone

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Forest Ecosystems 2022年第1期9卷 47-56页

作者： Yunni Chang Quanlin zhong Hong Yang Chaobin Xu Weiping hua Baoyin Li Fujian Provincial key laboratory for Plant Eco-physiology Fujian Normal UniversityFuzhou350007China College of Geographical sciences Fujian Normal UniversityFuzhou350007China state key {2. for Subtropical Mountain Ecology of the Ministry of science and technology and Fujian Province Fujian Normal UniversityFuzhou350007China College of Environmental science and Engineering Fujian Normal UniversityFuzhou350007China Department of Geography and Environmental science University of ReadingReadingUK College of Ecological and Resources Engineering Wuyi UniversityWuyishan354300China College of Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China

Background:Carbon(C),nitrogen(N),and phosphorus(P)stoichiometry is a key indicator of nutrient utilization in plants,and C/N/P ratios are related to the life histories and adaptation strategies of tree ***,no consensus has been reached on how leaf stoichiometric characteristics are affected by forest type and stand *** relationships between leaf stoichiometry and geographical,meteorological,and soil factors also remain poorly ***:Leaf and soil were sampled from forest stands of different age groups(young,middle-aged,near-mature,and mature)in two forest types(Chinese fir(Cunninghamia lanceolata)forests and evergreen broadleaved forests).The relationships between leaf C,N,and P stoichiometric parameters and geographical,meteorological,and soil factors were analysed by using redundancy analysis(RDA)and stepwise linear regression ***:Leaf C concentrations peaked in the near-mature stands with increasing age irrespective of forest *** N and P concentrations fluctuated with a rising trend in Chinese fir forests,while decreased first and increased later from young to mature phases in natural evergreen broadleaved *** fir forests were primarily limited by N and P,while natural evergreen broadleaved forests were more susceptible to P *** C,N,and P stoichiometric characteristics in Chinese fir forests were mainly affected by the soil total P concentration(SP),longitude(LNG),growing season precipitation(GSP)and mean temperature in July(JUT).The leaf C concentration was mainly affected by GSP and JUT;leaf N and P concentrations were both positively correlated with LNG;and leaf P was positively correlated with *** evergreen broadleaved forests,however,leaf stoichiometric parameters displayed significant correlations with latitude(LAT)and mean annual precipitation(MAP).Conclusions:Leaf stoichiometry differed among forest stands of different age groups and forest *** C,N,and P stoichiometry was pri

关键词： Leaf stoichiometry C/N/P ratios Environmental factors Stand age groups Chinese fir forest Natural evergreen broadleaved forest