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Search Results: 1 - 10 of 277173 matches for " 张昌雷 "
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基于对焦深度法的自动调焦方案设计与实验验证
The Scheme Design and Test Verification of Automatic Focusing Based on Depth from Focus Method
 [PDF]

, 汪向阳, 陈佐龙, 周磊, 孙明,
Journal of Sensor Technology and Application (JSTA) , 2015, DOI: 10.12677/JSTA.2015.33008
Abstract: 相比于传统自动调焦方法,基于图像处理的光电自动调焦技术具有智能化、速度快、准确性高、便于控制等优势,已成为自动调焦技术研究的主流方向。本文首先通过构建模型,详细阐述了基于图像处理的光电自动调焦原理和流程,并简要介绍了两种常用自动调焦方法;接着,基于对焦深度法给出了本文设计的自动调焦方案;最后,利用搭建的原理性样机开展了自动调焦实验,验证了本文方案的可行性。
Compared with the traditional automatic focusing method, the photoelectric automatic focusing technology has become the main research direction due to its advantages, such as high intelligence, speediness, accuracy and convenient control. In this paper, the principle photoelectric automatic focusing based on imaging processing is stated in detail, and two common automatic focusing methods are introduced in brief. Then, this automatic focusing scheme is designed and put forward. At last, the automatic focusing test is carried out, and its feasibility is verified.
基于搜索空间可调的自适应粒子群优化算法与仿真
段其,
控制与决策 , 2008,
Abstract: 针对收缩因子粒子群优化(CPSP)算法易陷入局部最优和发生过早收敛的问题.提出了基于搜索空间可调的自适应粒子群优化(APSO)算法.该算法根据种群早熟收敛程度和个体适应值,在算法停滞时,将全部粒子有效地划分在3类不同的搜索空间,使种群始终保持搜索空间的多样性,易于跳出局部最优,从而有效地改善了算法后期的寻优能力.
矿区废弃地先锋植物齿果酸模在pb、zn污染下抗氧化酶系统的变化
冬梅*?,群*?,红叶?
生态学报 , 2009,
Abstract: 作为云南矿区废弃地常见的先锋植物,齿果酸模(rumexdentatus)已形成对重金属污染的耐性生态型,是理想的逆境生态学研究实验材料。为进一步揭示不同抗氧化酶在先锋植物幼苗早期抗逆境的耐性机理中的作用,采集了来自云南兰坪铅锌矿废弃地的齿果酸模,观察其幼苗多种抗氧化酶在实验室模拟的重金属pb与zn单一污染条件下(浓度分别为0,1,5,10,50,100,200mg/kg)的变化特征。结果表明:随着pb与zn单一污染浓度的增加,(1)mda含量持续上升,与对照相比,在200mg/kgpb或zn单一污染下,mda分别显著上升了427%和330%;而(2)sod,pod与cat三者活性变化特征则各有不同。其中sod活性呈现先升后降的趋势,pod活性则持续上升;而cat活性很低,在zn污染下未检测出,pb污染下其变化无显著规律。相关性分析结果表明,pb与zn单一污染导致先锋植物齿果酸模幼苗产生膜脂过氧化,而抗氧化酶系统在抵御这种不良影响的耐性机制中发挥了一定的作用,且不同酶发挥的效用不同,其中pod发挥了主要作用。
Lead and zinc induced changes in activity of antioxidant enzymes of Rumex dentatus, a kind of pioneer plant growing on mine tailings
矿区废弃地先锋植物齿果酸模在Pb、Zn污染下抗氧化酶系统的变化

leidongmei,
冬梅
,,红叶

生态学报 , 2009,
Abstract: As one of common pioneer plants growing on mine tailings in Yunnan Province, Rumex dentatus has generated metal tolerant ecotype and could therefore be treated as an ideal experimental material for stress ecology study. To study the roles of different antioxidant enzymes in tolerance mechanism of pioneer plant early-stage seedling to stress, the variation characteristics of antioxidant enzymes of R. dentatus seedlings, sampled from Pb/Zn mine tailings in Lanping, Yunnan Province, were then investigated under exposing to different concentrations of Pb or Zn (0, 1, 5, 10, 50, 100, 200 mg/kg) for 48h in the laboratory. Our results showed that, with the increase of pollutant concentrations, (1) the content of malondialdehyde (MDA) went up sustainably, and had significantly increased respectively to 427% and 330% under the concentrations of 200 mg/kg Pb or Zn when compared with normal control; whereas (2) the activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) varied to different extents. Specifically, SOD increased initially but decreased afterwards, and POD increased sustainably; whereas the activity of CAT could neither be detected under Zn stress nor effectively estimated under Pb stress. Subsequent correlation analyses suggested that the antioxidant enzymes have produced some protective effect in the tolerance reaction against Pb and Zn pollution, among which POD has plausibly played the central role.
金环蛇(Bungarus fasciatus)蛇毒类心脏毒素的纯化及生化分析
,洪基,克健
动物学研究 , 1981,
Abstract: 金环蛇(Bungarus fasciatus)蛇毒经磷酸纤维素P11柱层析分离所得的第8峰(即类心脏毒素),再经磺乙基—葡聚糖凝胶G—25柱层析分离得8A、8B。再将8A、8B分别经葡聚糖凝胶G—50柱层析,得纯化的类心脏毒素A、B。经聚丙烯酰胺凝胶电泳鉴定为单一的条带。无酶活性。其氨基酸组成及含量基本与Shiau Lin 1975等所测定的结果一致。
胶东大庄子构造角砾岩型金矿床地质地球化学特征及其成矿流体来源探讨
邹为,李光明,
矿床地质 , 2010,
Abstract: 大庄子金矿受胶莱盆地边缘发育于荆山群内的顺层状低角度断裂带控制,以大理岩质碎裂岩及角砾岩等张性构造岩胶结物发生矿化为特点。容矿岩石与成矿流体具有强烈的物质交换,矿化与SiO2、Fe2O3、Na2O及As、Cd、Hg、Cu、Pb等元素关系密切。矿石具有富集轻稀土元素、铕正异常的特征,其稀土元素特征和基性脉岩具有一定的相似性,又具有原岩的一些特点,表明容矿岩石受到了深部成矿流体的影响。硫、铅、碳-氧及氢-氧等同位素地球化学及流体包裹体研究显示,成矿物质较复杂,成矿流体来源于地壳深部或上地幔的岩浆热液,在成矿作用中,萃取了部分围岩,并与围岩发生了强烈反应。
既有建筑围护结构综合热工性能评价方法研究
,小慧,,王琳
- , 2018,
Abstract: 针对既有建筑围护结构提出了一种综合热工性能评价方法——等效传热系数法.等效传热系数评价法是基于指标评价法和等效能耗模型提出来的,将围护结构多个参数指标综合为一个等效指标,通过比较既有建筑和标准节能建筑的等效传热系数来评价既有建筑围护结构的热工性能与节能潜力.研究分析表明,该方法只需要测试室内外温度,不需要对围护结构各项热工性能参数进行全面布点测试,可以克服既有建筑围护结构现场测试困难和实际围护结构热工性能并不均衡难以全面把握的问题,缩短围护结构热工性能诊断周期.可以用于指导既有建筑围护结构的节能改造.
This paper proposed a method for the comprehensive thermal performance assessment (equivalent heat transfer coefficient) of building envelopes in existing buildings. This method is based on the index evaluation and equivalent energy consumption model, which integrates many evaluation indexes into an equivalent index. The thermal performance and energy-saving potentiality of the building envelope are evaluated by calculating and comparing the heat transfer coefficient of the two equivalent energy consumption models. It is shown that only measurement of indoor and outdoor temperature is needed, while measurement of every parameter in the envelope structure is not needed, which can overcome the difficulties in testing the existing buildings with complex structures. The proposed method can assess the total thermal performance of building envelope rapidly and evaluate the necessity of retrofitting before energy-saving renovation.
根系互作对间作玉米大豆氮和磷吸收利用的影响
,汤利,董艳,郑毅
南京农业大学学报 , 2016, DOI: 10.7685/jnau.201601010
Abstract: [目的] 探明根系互作对玉米大豆氮、磷吸收利用的影响,为作物高产优质提供依据。[方法] 通过水培试验,来实现根系互作效应,共设3个处理:单作玉米、单作大豆、间作玉米大豆。处理13、31、45、57 d时采样分析植株各部位的氮、磷含量。[结果] 根系互作提高了玉米各器官与地上部氮、磷累积量,而大豆各器官及地上部氮、磷累积量则表现出了根系互作劣势。与单作相比,间作玉米地上部氮累积量在处理13和31 d分别提高了224.6%和24.0%(P<0.05),但是在后期,与单作相比有所降低。在处理13和45 d时,与单作相比,间作玉米地上部磷累积量提高了145.8%和46.4%(P<0.05)。与单作相比,处理13、45、57 d时,间作大豆地上部氮累积量分别降低了47.5%、34.9%、46.0%(P<0.05),处理13、31、45、57 d时,间作大豆地上部磷累积量分别降低了17.5%、24.9%、14.5%、40.1%(P>0.05)。[结论] 根系互作提高了玉米各器官及地上部氮、磷累积量,因此,玉米大豆间作体系具有明显的氮、磷吸收利用优势。
[Objectives] The paper aims to explore the effect of interaction roots on soybean and maize’s absorption and utilization of nitrogen and phosphorus,to provide the basis for high-qualit and high-yield crops.[Methods] Through hydroponic experiment,this study implemented the interaction effect of root,with three treatments:monoculture maize,monoculture soybean,maize and soybean intercropping.According to the processing after 13,31,45 and 57 d sampling analysis,root,stem and leaf were separated,and then the crush was dried to measure the nitrogen and phosphorus,with molybdenum antimony colorimetric method.[Results] Root interactions improved nitrogen and phosphorus accumulation of the maize organs and aboveground,howere,nitrogen and phosphorus accumulation of soybean organs and aboveground showed root interaction as disadvantage.Compared with the monoculture,nitrogen accumulation of aboveground interplanting maize after processing 13,31 d incresded by 224.6% and 24.0%(P<0.05),respectively,but in the later stage,it was lower than monoculture. After treatment of 13,45 d,compared with monoculture,the phosphorus accumulation of maize with interplanting increased by 145.8% and 46.4%,respectively(P<0.05).Compared with monoculture,after treatment of 13,45,57 d,nitrogen accumulation of aboveground soybean interplanting was reduced by 47.5%,34.9%,46.0%(P<0.05)respectively,after treatment of 13,31,45,57 d,phosphorus accumulation of aboveground interplanting soybean reduced by 17.5%,24.9%,14.5%,40.1% respectively(P<0.05).[Conclusions] Root interactions improve organs and nitrogen and phosphorus accumulation of aboveground with maize. Therefore,maze and soybean intercropping system has obvious advantages in nitrogen and phosphorus absorption and utilization
节能减排:中国能源战略的必然选择
Energy Conservation and Emission Reduction: An Inevitable Choice of China’s Energy Strategy
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Sustainable Energy (SE) , 2016, DOI: 10.12677/SE.2016.61003
Abstract:
随着科学技术的发展,人类文明的进步最终实现了生命物质能量向非生命物质能量(矿物燃料)的根本性转变。全球实践表明,大量矿物燃料使用所产生的极化效应正在对人类文明的可持续发展形成日趋严峻的挑战。为此需要重新思考人类的能源利用行为模式。作为世界最大的能源消费和碳排放国,中国未来低碳经济的发展应遵循从目前的“重开发、轻使用”传统能源利用模式向“使用与开发并重”模式的过渡,并最终定格于“重使用、轻开发”的地球友好能源利用模式。
The progress of human civilization has reached a crucial transition of energy use. In the past, the widespread use of mineral fuels has not only brought about remarkable increases in wealth (as measured by the Gross Domestic Product, for example) but also resulted in increased environ-mental pollution, as indicated by heightened CO2 emissions. This phenomenon, which is referred to as the bipolarized effect of energy use, has hindered future sustainable development. Therefore, it is important to consider new methods for building models of energy use in order to develop a low-carbon economy, just like China’s common saying “energy conservation and emission reduction”. As the largest consumer of fossil fuels and the largest emitter of CO2 of the world, China may face mounting challenges in protecting its vulnerable environment unless it can successfully transit from the traditional economic model, which promotes energy exploitation rather than energy conservation, to a model that considers energy exploitation and conservation equally and, finally, to a model that focuses primarily on energy conservation.
海底环境促使C4, C5异构体分异因素的研究
陈立,贺行良,,培玉,媛媛,李凤
海洋科学 , 2014, DOI: 10.11759/hykx20130112002
Abstract: 模拟海底微环境,研究促使C4,C5异构体分异的因素。39d后,i-C4/n-C4变化率:灭菌固液混合组为1.67%,灭菌固液分离组为7.96%,未灭菌固液混合组为2.54%,未灭菌固液分离组为14.21%;i-C5/n-C5变化率:灭菌固液混合组为1.19%,灭菌固液分离组为8.18%,未灭菌固液混合组为2.26%,未灭菌固液分离组为10.19%。表明海底环境对烷烃组分产生复杂的溶解、吸附和生物降解作用,使异构体产生分异效应;碳原子数增加,综合作用相对减弱;同碳原子数,对正构烷烃的作用效果更显著。碳同位素分析发现:i-C4,n-C4,i-C5,n-C5的δ13C均有微弱的变重趋势,CO2的δ13C则发生明显的变轻趋势,并且未灭菌组比灭菌组变化大。表明海底环境使烷烃组分发生了碳同位素分馏,生物降解作用显著。
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