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Search Results: 1 - 10 of 327029 matches for " 王立侠 "
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中国牧草生物技术的研究现状和展望
,李桂民,路云,德利
草地学报 , 2009, DOI: 10.11733/j.issn.1007-0435.2009.03.023
Abstract: 牧草在家畜业、环境保护和土壤保持方面都有重要的作用。因此,它比其他的农作物有较高的经济价值。由于牧草种类的复杂性和传统牧草育种遇到的困难,现在人们已经认识到生物技术手段在发展改良牧草品种中的巨大潜力。近来我国在应用生物技术进行牧草遗传改良方面已经取得了许多成就,这为遗传育种的成功提供了有效的策略。本文就近年来生物技术在牧草遗传改良方面研究进展及其应用进行全面的综述,内容包括组织培养、细胞工程、分子标记、基因工程和遗传转化系统;提出了目前我国牧草生物技术研究中亟待解决的一些问题和进一步发展方向,如提高牧草的抗性和品质,建立高效的转化系统,功能基因克隆,转基因牧草风险评价等。
A new method of anisotropic pre-stack depth migration
东濮凹陷的各向异性叠前深度偏移方法

秦亚玲,,秦广胜,彦春,刘学清,王志刚
地球物理学进展 , 2010,
Abstract: The Dongpu depression is a faulted basin with versatile depositional environment, broken fault-blocks and complicated structures. Its local structure is controlled by faults. There are major lateral velocity alternations because of different buried depths of contemporaneous strata in the two sides of faults. But time migration is unable to work out this problem, so anisotropic pre-stack depth migration has been applied to this area, and high density velocity analysis is ombined with acoustic logging data. The results show coincidence of seismic and drilling with anisotropy PSDM.
利用秀丽线虫进行纳米材料安全性评价研究进展
,武秋,李隐,叶波平,大勇
中国公共卫生 , 2012, DOI: 10.11847/zgggws2012-28-04-61
Abstract: ?鉴于纳米材料易于进入生物体内且已经进入生活环境,有关其生物安全性及相应毒理学研究日益受到关注(1-2)。
3D seismic geometry design based on ore-stack imaging
基于叠前成像的三维地震观测系统设计

秦广胜,蔡其新,汪功怀,秦亚玲,
地球物理学进展 , 2010,
Abstract: The main objective of conventional 3D seismic geometry design is to obtain regularly sampled stacking dataset, which can be used to achieve good images through post-stack migration. However, pre-stack migration has strict requirements on seismic geometries. In order to exert the technical advantages of pre-stack migration and improve the accuracy of seismic images, it is very important to design seismic geometries based on pre-stack imaging. This article puts forward an approach of seismic geometry design based on pre-stack imaging. The first step is to design the basic spatial sampling of seismic geometry based on the anti-aliasing criteria of pre-stack migration. The second is to design the layout of seismic geometry according to the rule of regular sampling and uniform bin attributes. Then, it optimizes step by step and finalizes seismic geometry by using techniques such as focal beams, pre-stack migration response of scatter point, forward modeling, and wavefield illumination. This method has been applied to high accuracy seismic exploration of the Zhongyuan Oilfield in recent years and it has obtained very good results.
基于小波分析的MSMA振动传感号处理与故障检测
鲁军,,重马,于庆洋,高琳,
电工技术学报 , 2015,
Abstract: 基于磁控形状记忆合金(MSMA)逆特性制作的振动传感器,其输出的感应电压存在较大的干扰,需要对感应信号进行数字滤波以提取有效数据。本文在小波分析滤波原理基础上,采用db5小波数字滤波算法,将不同频段的感应电压信号进行软阈值滤波,并通过小波分解MSMA振动传感器的感应信号进行故障检测。由信号处理结果可以看出小波分析具有理想的滤波效果,可用于MSMA振动传感器的信号处理与故障检测。
松嫩平原农牧渔交错区生态敏感性评价研究——以杜尔伯特蒙古族自治县为例
魏文,衍臻,陈秀万,江淼,
地球信息科学学报 , 2008,
Abstract: 生态敏感性评价对区域生态环境建设治理具有重要实践意义和科学价值。本论文在RS、GIS技术支持下,采用ETM影像、土壤分布特征以及其他相关地理信息,选用土壤类型、植被覆盖程度、土地利用现状等作为生态敏感性评价的主要因子,并利用层次分析法确定评价因子的权重值,建立生态敏感性评价模型,对农牧渔交错区(以杜尔伯特蒙古族自治县为例)进行生态敏感性评价的研究。该文的研究结论是低度生态敏感区以湿地生态系统和湖泡生态系统为主,包括生态状况维持较好的草原区域,抗自然灾害能力较强;中度生态敏感区以农田、草原复合生态系统为主,具有一定的生态恢复能力,能抵抗适度的人为扰动;高度生态敏感区以沙土农田、沙地草原以及湖泡周围的盐碱地生态系统为主,自我调节能力弱,相对稳定性较差。本文研究表明,利用遥感技术获取影像信息,结合地理信息系统相关空间分析方法进行区域的生态敏感性评价,具有实际可操作性,评价结果合理可靠,可以为区域生态建设提供科学依据。
大白菜-结球甘蓝2号单体异附加系的floweringlocusc(flc)基因鉴定
顾爱,,赵建军,许愿超,彦华,申书兴
农业生物技术学报 , 2014,
Abstract: ?floweringtimeisanimportanttraitinbrassica,andfloweringlocusc(flcs)arekeygenestoflowering.inthispaper,flcsspecificprimers,polymorphicnotonlyinbrassicarapassp.pekinensisandb.oleraceavar.capitata,respectively,butalsobetweenb.rapassp.pekinensisandb.oleraceavar.capitata,usingdnasamplesfrom4differenttypeofb.oleraceavar.capitataand4differenttypesofb.rapassp.pekinensisindividualplants,werescreened.the4specificprimerswereobtainedforgenotypingofbrflc1,brflc2,brflc3,brflc5,boflc1,boflc2,boflc3andboflc5.forwardprimersweredesignedonpolymorphicregionofexon4,andreverseprimersweredesignedonconservedregionofexon7.thecorrespondingflcsbetweenb.rapassp.pekinensisandb.oleraceavar.capitatacouldbeidentifiedby1pairofprimers.theflcsfromb.rapassp.pekinensisandb.oleraceavar.capitatain1cellcouldbedifferentiatedeasilyandquicklyusing4specificpairsofprimers.thesameflcsspecificbands,amplifiedby4specificprimers,appearedinsesquidiploidshybrid(aac)drivedfromtetraploidb.rapassp.pekinensis(aaaa)anddiploidb.oleraceavar.capitata(cc),aswellasinb.rapassp.pekinensisandb.oleraceavar.capitata.intheb.rapassp.pekinensismonosomicalienadditionline,whichintroducedchromosome2fromb.oleraceavar.capitata,besidesthe4brflcsgenes,onlyboflc3existedinthemonosomicalienadditionline,detectedby4specificprimers.theresultsprovideanewwaytoidentifyboflcsinthebackgroundofb.rapassp.pekinensis,andsupplyspecialmaterialsfortranslocationlinesaddedboflc3underb.rapassp.pekinensisbackground.
应用生物农药防治稻水象甲的试验研究
李晓光,,刘影,钟燕,马景勇,史树森
吉林农业大学学报 , 2004,
Abstract: ?采用室内药浸法和室外常规喷雾法进行了几种生物性杀虫剂防治稻水象甲的试验研究。结果表明:质量分数为24.5%多虫螨丁乳油500倍液、质量分数为0.12%灭虫丁可湿性粉剂500倍液处理后的防效与对照质量分数为36.8%维稻乳油相当;质量分数为0.26%苦参碱水剂300倍液、质量分数为46%杀苏可湿性粉剂500和1000倍液、质量分数为0.12%灭虫丁可湿性粉剂1000倍液的防效均低于对照。
神农架巴山冷杉林凋落物量养分归还及分解特征
崔鸿,,,黄志霖,,晓荣,庞宏东
南京林业大学学报(自然科学版) , 2017, DOI: 10.3969/j.issn.1000-2006.2017.01.030
Abstract: 【目的】掌握森林凋落物产量及组成的动态变化、凋落物养分归还量及凋落物分解特征,了解凋落物在森林生态系统养分循环中的作用。【方法】选择神农架巴山冷杉天然林和人工林,在样地内布置凋落物收集框和凋落物分解袋,通过1 a的连续观测,比较天然林和人工林凋落物产量及分解速率的差异。【结果】巴山冷杉天然林和人工林年凋落物总量分别为6 217.44和4 833.46 kg/hm2,天然林比人工林年凋落物总量高28.63%。凋落物中以落叶为主,天然林和人工林落叶产量分别占凋落物总量的55.24%和54.76%; 其次是落枝,分别占总量的22.18%和19.66%; 树皮及花果等其他组分含量相对较少,分别占总量的22.58%和25.58%。巴山冷杉林凋落模式为双峰型,分别在10月和次年6月具有明显高峰期,而在次年2月凋落量最小。天然林和人工林凋落物养分年归还量分别为77.84和54.47 kg/hm2,天然林比人工林凋落物年养分归还量高42.91%,5种大量元素年归还量大小顺序均为N>K>Ca>P>Mg。凋落物在初始阶段分解较快,天然林和人工林凋落物在最初2个月失重率分别达18.70%和11.35%。天然林和人工林凋落物分解常数分别为0.303和0.241,凋落物半衰期分别为1.70 a和2.57 a,而凋落物周转期分别为9.30 a和12.12 a。【结论】神农架巴山冷杉林凋落物产量较高,分解速率较慢,天然林凋落物对土壤的改良效果更好。
【Objective】 In order to reveal functions of litter in nutrient cycling of forest ecosystem, the dynamics of litter production and components, nutrient return and characteristics of decomposition process were studied in this paper. 【Method】We choose the natural and plantation forest of Abies fargesii in Shennongjia,and arranged litter collection boxes and decomposition bags in the sample area, to compare the litter production and decomposition rate differences between the natural forest and plantations through one year of continuous observation.【Result】①The total litter production of natural forest and plantation were 6 217.44 kg/hm2 and 4 833.46 kg/hm2, respectively, which of the natural forest was 28.63% higher than that of the plantation. ②The main litter fractions were leaves which accounted for 55.24%(natural forest)and 54.76%(plantation)to total litters, then the twigs(22.18%, 19.66%), and the barks, fruits and others were less relatively(22.58%, 25.58%). ③The annual dynamics mode of litter production was double peak curve, and the peak occurred in October and next June, and the nadir occurred in next February. ④The annual nutrient returns of natural forest and plantation forest were 77.84 kg/hm2 and 54.47 kg/hm2 respectively, which of the natural forest was 42.91% higher than that of the plantation, and the order of macro-element return was N>K>Ca>P>Mg. ⑤The litters were decomposed more fast in the initial phase, as the litter weight loss rate of natural forest and plantation express 18.70% and 11.35%,respectively. The litter decomposition constants of natural forest and plantation forest were 0.303 and 0.241, the half declining were 1.70 and 2.57 years, and the total declining were 9.30 and 12.12 years. 【Conclusion】 The litter production of A. fargesii forest is abundant, the litter decomposition rate of it is slow, and the effect of litters on soil improvement in natural forest is better than that in the plantation forest
舰载机着舰侧回路时变风险权值矩阵线性变参数预测控制
Aircraft lateral linear parameter varying model predictive control with time varying weight

朱齐丹,,张智,闻子
控制理论与应用 , 2015, DOI: 10.7641/CTA.2014.40224
Abstract: 针对舰载机钩索阻拦阶段, 提出阻拦风险函数的概念和计算方法, 通过离线计算获得时变状态权值矩阵和时变控制输入权值矩阵. 采用时变状态权值矩阵可以实时调整各状态之间的变化关系, 而时变的控制输入权值矩阵能够调整副翼和方向舵的输入峰值, 避免出现输入饱和情况, 提高横侧向自动着舰的效率和安全性. 建立了时变的系统输出约束函数, 增加了舰载机进舰阶段控制器的可解性. 建立了基于状态偏差的舰载机横侧向着舰模型, 针对舰载机上很多状态不能直接测量的特点, 采用离线设计状态观测器的方法来估计舰载机的真实状态值, 利用线性矩阵不等式求解系统最优解, 通过舰载机自动着舰三维仿真模拟平台验证了算法的可行性.
The concept and calculation method of arresting risk function are provided for the carrier aircraft hanging and arresting stage. Time-varying weight matrix of states and controlling inputs can be acquired by means of off-line calculation. The varied relation-ship between different states could be adjusted by employing time-varying states weight matrix in real time. At the same time, the controlling peak of aileron and rudder can be adjusted by varying controlling inputs weight matrix to avoid inputs saturation in real time. Therefore, the efficiency and safety of aircraft automatic landing could be improved. Time-varying system output constraint function is established to increase the feasibility of controller in the aircraft initial leading stage. Carrier aircraft lateral landing model is set up based on state deviations. For many states of the aircraft could not be measured directly, an off-line states observer is designed to estimate the real states of aircraft. Optimal solutions are solved by linear matrix inequalities. The simulation results verify the feasibility of the algorithm in the aircraft automatic landing three-dimensional simulation platform.
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