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Search Results: 1 - 10 of 256453 matches for " 刘兴洪 "
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地震波场的共偏移距延拓研究
耀,
地球物理学报 , 1999,
Abstract: 实现地震波场共偏移距剖面上不同偏移距之间的转换,对于精确的共反射点叠加、速度分析以及研究AVO信息等皆具有重要意义。本文从非均匀介质地震记录的微分性质出发,通过对其共反射点变化轨迹的研究,导出基于Hamilton方程的地震波场共偏移距延拓方程,建立了新的共偏移距延拓算子,通过理论模型的计算验证了此方程的正确性。
基于环境同位素技术的再生水灌区水循环特征解析
A Study of Water Cycle in Reclaimed Water Irrigation District with Isotopic
 [PDF]

, 吴文勇, , 尹世洋
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.16067
Abstract: 再生水灌区水源包括再生水、地表水、地下水等,准确、客观的表征再生水灌区各水源之间的相互转换关系是开展多水源联合调度保障灌区用水安全和提高水资源利用率的关键。本研究采用环境同位素和水化学成分作为平原灌区水循环研究的示踪剂,揭示了灌区水循环特征。结果表明,灌区地表水和地下水之间存在强烈的水力联系,整个灌区的补给排泄关系主要是地表水补给地下水,人工抽取河道再生水灌溉农田产生深层渗漏,补给地下水是导致灌区地下水电导率明显波动变化的主要原因,同位素分析结果显示灌区再生水、地表水和地下水均呈现出强烈的蒸发浓缩作用,地表再生水对地下水的补给从北到南逐渐减弱。
In reclaimed water irrigated district, the water resources characteristic with synthetic reclaimed water, stream water, ground water and so on. It is essential for security and efficiency utilization of reclaimed water to precisely assess the transformation among different water bodies in reclaimed water irrigation district. This study uses isotopic and hydrochemical data of water samples to quantity study the regional water cycle. It has shown that there is intense hydraulic connection between surface water and ground water. Most ground water is recharged from surface water. The reclaimed water irrigation is one of most important way for reclaimed water recharged to groundwater and results in obvious unstable variation of EC. The results of ground water isotopic composition showed an intense evaporation-concentration process during recharge from precipitation and surface water. The ground water isotopic concentration gradually decreases from Northwest to Southeast and results by decrease of surface water recharge to ground water.

 

北京市再生灌区地下水动态特征及数值模拟研究
Groundwater Dynamic Characteristics and Numerical Simulation for Reclaimed Water Reclaimed Water Irrigation District
 [PDF]

尹世洋, 吴文勇, ,, 徐小元
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.16070
Abstract: 本文基于GMS软件建立了北京市再生水灌区地下水数值模型,预测了不同情景下地下水的动态变化趋势及调控方案。研究表明,随着再生水灌区的再生水利用率逐步提高,灌区内的地下水水位逐步抬升,向下游地区的侧向排泄量也呈加大趋势;为了减少下游的侧向排泄量、避免该区域由于地下水位过高而产生土壤次生盐渍化,应控制灌区内的地下水位埋深;再生水利用率达到50%时,每年需开采出3307.2m3置换的浅层地下水资源,再生水利用率达到70%时,每年需开采出4567.0m3置换的浅层地下水资源,再生水利用率达到90%时,每年需开采出6128.3m3置换的浅层地下水资源。研究成果对再生水的安全利用、地下水资源的涵养具有重要意义。
 In order to predict the changing trends of groundwater under different scenarios and make regulation programs, a groundwater numerical model of reclaimed water irrigation district is developed based on GMS software. Research results indicate that with the gradual increase of reclaimed water utilization, irrigation area groundwater level progressive uplift, lateral excretion to the lower reaches also show a trend of increase. In order to avoid the soil salinization, shallow groundwater resources must be mining to control the depth of groundwater according to the different utilization rates of the reclaimed water. 50% of total water consumption is reclaimed water, 33.1 million m3 replacement of shallow
实施最严格水资源管理制度面临的技术问题与挑战
Technique Controversies and Challenges of Applying the Strictest Water Resources Control System
 [PDF]

德地, 郭生练, 郭海晋,
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.33024
Abstract:

我国水资源面临的形势十分严峻,水资源短缺、水污染严重、水生态环境恶化等问题日益突出,已成为制约经济社会可持续发展的主要瓶颈。最严格水资源管理制度是解决我国水问题的有效途径。本文根据最严格水资源管理制度的内涵,在阐述最严格水资源管理与水资源优化配置关系的基础上,分析了目前水资源优化配置研究面临的技术问题与挑战,并从最严格水资源管理的考核要求出发,提出了在最严格水资源管理制度下,动态的水资源优化配置模型结构、求解算法和方案评价等方面的对策和建议,从而为实施最严格水资源管理制度提供技术支撑和保障。
China faces a very serious situation of water resources, with increasingly conspicuous problems of water resources shortage, serious water pollution, deterioration of the water ecological environment, and so on, which have become major bottlenecks inhibiting sustainable economic and social development in the country. Applying the strictest water resources control system is the most effective way to solve these water resources problems. The optimal water resources allocation is the core issue of the strictest water resources control system. The challenges and controversies in optimal water resources allocation research under the strictest water resources control system have been analyzed according to the relationship between the strictest water resources control and the optimal water resources allocation. In order to satisfy the requirements of the strictest water resources control system, the dynamic structure of new water resources allocation model, the optimal solution algorithms and the scheme evaluation methods have been presented and suggested. What have been analyzed and suggested in this paper will be very helpful for applying the strictest water resources control system in China.

丹江口水库夏秋汛洪水相关性规律研究
Correlation Analysis of Summer and Autumn Floods for Danjiangkou Reservoir
 [PDF]

胡瑶, 郭生练, 章君,
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.32019
Abstract: 研究丹江口水库夏汛期洪水和秋汛期洪水的相关性规律,可以为丹江口水库秋汛期防洪和提前蓄水提供科学依据,有利于充分发挥水库的防洪、供水与发电等综合利用效益。利用优选的Copula函数建立丹江口水库的夏秋汛洪峰和最大7日洪量的联合分布,并进行条件概率分析,得出当夏汛期洪峰和最大7日洪量发生不同等级的洪水时,秋汛期的条件概率和洪水等级的分布。分析结果表明:丹江口水库夏秋汛洪水的实测资料具有一定的相关性规律。当夏汛期最大7日洪量发生小洪水时,秋汛期最大7日洪量发生小于二十年一遇的洪水概率为95.3%,发生小于五十年一遇的洪水概率为98.1%
Correlation rules of summer and autumn floods can provide a scientific basis for the autumn flood prevention and impoundment of Danjiangkou Reservoir, and are conducive for the reservoir’s flood control, water supply, power generation and other utilization efficiency. The optimized Copula function was used to establish the joint distribution of summer and autumn flood peaks and maximum 7-day flood volume respectively for Danjiangkou reservoir. The distributions of conditional probability during autumn flood season were derived and analyzed when the flood peak and maximum 7-day flood volume during summer flood season occur with different grades. Analysis results show that there are certain regularities between the summer and autumn floods of Danjiangkou reservoir basin. When small flood flow occurs during the maximum 7-day flood volume
赣江流域未来降雨径流变化模拟预测
Simulation and Prediction of Future Precipitation and Runoff Change in the Ganjiang Basin
 [PDF]

王乐, 郭生练, , 郭家力, 章君
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.36064
Abstract:
本文采用BCC-CSM1.1全球气候模式,在IPCC5推荐的三种代表性浓度路径RCP2.6、RCP4.5和RCP8.5情景下,应用SDSM统计降尺度技术将GCM输出进行降解,并作为分布式两参数月水量平衡模型的输入,模拟预测赣江流域未来的降雨径流变化。结果表明:在三种浓度路径下,2020s和2050s时期年径流量均比近期减少,2080s时期则存在差异:RCP2.6和RCP4.5浓度两种路径下的年径流量与近期基本持平,而RCP8.5浓度路径下相对近期有明显的增加。同时,未来主汛期径流减少,非汛期径流呈现不同程度的增加,气候变化在一定程度上有可能减轻赣江流域未来汛期的防洪压力和枯水期的供水压力。
The SDSM statistical downscaling technique was adopted to degrade the output of BCC-CSM1.1 model under three representative concentration pathways: RCP2.6, RCP4.5 and RCP8.5 scenarios recommended by IPCC5. Future precipitation and temperature series were as inputs of distributed two-parameter monthly water balance model to simulate and predict future runoff change in the Ganjiang basin. The results show that under three representative concentration pathways, simulated annual runoff volumes of 2020s and 2050s are both less than the reference value in the recent period, but there are differences for 2080s period: under RCP2.6 and RCP4.5 concentration pathways, the simulated annual runoff volumes are almost equal to the recent reference value, while more than the recent reference value under RCP8.5 concentration pathways. Meanwhile, future runoff volume decreases in the main flood season and increases in dry season, which implies that climate change is likely to alleviate flood control pressure during flood season and water supply pressure during dry season to some extent in the Ganjiang basin.
气候变化对赣江流域洪水频率的影响分析
Impact of Climate Change on Flood Frequency in the Ganjiang Basin
 [PDF]

郭家力, 郭生练, 张志强, , 章君, 王乐
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.36066
Abstract:
本文利用最新的IPCC第五次评估报告AR5发布的BCC-CSM1.1数据与SDSM统计降尺度方法耦合驱动新安江水文模型,对气候变化情景下赣江流域未来洪水的变化趋势进行分析和探讨。结果表明,RCP2.6、RCP4.5和RCP8.5情景下洪水量级相对于基准期分别减小15%、9%和11%左右。三种情景下,未来不同时期的洪水均值、最大值和最小值的洪水重现期在基准期下均有不同程度的减小,其中最大值洪水减小幅度最大,1000年一遇洪水仅相当于基准期100年一遇,150年一遇洪水仅相当于基准期15年一遇。
The Xinanjiang hydrological model was driven by the SDSM statistical downscaled BCC-CSM1.1 outputs, which were released in the latest IPCC fifth assessment report AR5 to explore flood fre-quency changes of the Ganjiang basin under future climate change scenarios. The results indicate that the averages of flood magnitude with different return periods under the RCP2.6, RCP4.5 and RCP8.5 scenarios are reduced by 15%, 9% and 15% relative to the baseline period, respectively. The return periods of average, maximum and minimum floods of future different periods reduce in some extents. The annual maximum flood reduces remarkably; a design flood of 1000-year (or 150-year) return period under future scenario is equal to that of 100-year (or 15-year) under the baseline period.
夏季长江口及邻近海域水母类生态特征研究
,
海洋科学 , 2010,
Abstract: 利用2003年6月和2006年6月在长江口及邻近海域进行的两次大面调查所采集的浮游动物网采样品,对长江口及邻近海域水母类的种类组成、优势种、数量分布及生态类群等进行了探讨。结果表明:研究水域共记录水母类77种,其中水螅水母60种,管水母12种,钵水母1种,栉水母4种。优势种有:五角水母(Muggiaeaatlantica),双生水母(Diphyeschamissonis),拟细浅室水母(Lensiasubtiloides),四叶小舌水母(Liriopetetraphylla),两手筐水母(Solmundellabitentachlata),嵊山秀氏水母(Sugiurachengshanense)和瓜水母(Ber?ecucumis)等。其中水螅水母类的优势种存在较大的年际变化,2003年为嵊山秀氏水母,2006年为四叶小舌水母和两手筐水母。研究水域内水母类平面分布不均匀,2003年平均丰度为13.3个/m3,除在长江口外存在一个由河口低盐种贝氏拟线水母(Nemopsisbachei)大量聚集形成的高值区外,在舟山群岛南部还存在一个密集中心;2006年水母类丰度略有上升,平均丰度为16.0个/m3,与2003年相比,其密集中心向东北部偏移。2006年6月研究海域温、盐较2003年同期均大幅升高是造成两航次优势种类更替及水母类分布变化的主要原因。
非定长相关时间序列集内平均序列的摆动异常及其解释
滨?,周江
气象学报 , 2003, DOI: 10.11676/qxxb2003.048
Abstract: 文中对多个时间序列的平均序列中常常出现的异常摆动问题进行了探讨.结果表明,给定时间序列集中序列个数的多少会造成其所组成的平均序列的方差的变化,即序列个数越多,平均序列方差越小的可能性就越大,由此定义了方差增长率α.当给定方差增长率限定值α0并使其满足α≤α0时,可以得到最小序列个数m0,且α0越大或序列间平均相关系数越大,所需要的时间序列数越少.这一结果可应用于气候变化研究中有关平均时间序列建立的研究中,亦可运用到其他相关研究领域.
坛紫菜雌雄叶状体的细胞分化比较
,旭升 ?
水产学报 , 2007, DOI: 10.3724/SP.J.1231
Abstract: 以室内培养20~90d的坛紫菜雌雄叶状体为研究材料,用酶解法分别获取单离细胞进行再生培养。在雌雄叶状体的体细胞再生体中,都出现9种不同发育类型。再生体发育类型的数目和比例与种藻日龄密切相关等结果,证实了离体培养的单离细胞发育成不同形态的再生体是基于其离体前处于不同分化时期所致;由壳孢子分化成性母细胞大致可划分成8个不同阶段。雌雄叶状体的细胞分化途经大致相同,但也有一定差异,雌性叶状体的细胞最终分化成雌性性母细胞,并产生大量的丝状体;而雄性叶状体的细胞最终分化成雄性性母细胞,绝大部分生成精子,但极少数产生丝状体。在雌雄叶状体的细胞再生体中,均产生“类单孢子”并长成正常叶状体。雄性叶状体成熟较雌性早,与其细胞分化速度较快有关。成熟期不同的雌性品系观察结果表明,叶状体成熟越早、生长期越短,其体细胞分化速度也越快。
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