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三峡库区植物篱系统土壤颗粒分布及粘粒与土壤理化性质关系
Soil Particle Distribution and Relationship between Soil Silt Concentration and Physicochemical Properties of Hedgerow Systems in the Three Gorges Reservoir Area
 [PDF]

, 张洪江, 陈奇伯
Hans Journal of Soil Science (HJSS) , 2014, DOI: 10.12677/HJSS.2014.23003
Abstract:
在调查分析长江三峡库区现有坡耕地植物篱的配置方式、生长状况和室内分析植物篱系统内土壤颗粒组成和土壤理化性质的基础上,对3种植物篱系统中土壤颗粒分布特征及土壤粘粒与土壤理化性质的关系进行了研究,结果表明:1) 植物篱系统中不同位置土壤颗粒含量存在显著差异,乔木类、草本类和灌木类植物篱带间坡耕地土壤砂粒含量比其对应的植物篱带内土壤砂粒平均含量分别高10.4%,13.7%和9.2%;而粘粒含量在植物篱带内富集,其平均含量比植物篱带间坡耕地土壤粘粒含量分别高14.3%,19.5%和10.7%;2) 植物篱系统内土壤粘粒含量与土壤孔隙度、土壤含水量、饱和导水率、土壤抗冲指数、土壤抗蚀指数、水稳性团聚体极显著正相关,而与土壤容重呈显著负相关关系。3) 土壤粘粒含量与土壤全氮、有效氮、土壤全钾、有效钾、全磷、有效磷和阳离子交换量具有极显著正相关关系。
To achieve the soil particle distribution characters and the relationship between physicochemical properties of hedgerow systems in the Three Gorges reservoir area, soil particle size composition and physicochemical properties of soil collected from different position in hedgerow systems with different species were tested, and the coefficient between soil silt concentration and physico-chemical properties were analyzed. The result revealed that 1) the particle size concentration in the hedgerow systems diversified significantly. The soil sand concentration in the steep land be- tween hedgerows with different species was higher than that of soil within hedgerows stipe, by 10.4%, 13.7% and 9.2% respectively. However, the soil silt concentration enriched within hedge- rows strip, and the mean value of soil silt concentration with different species increased by 14.3%, 19.5% and 10.7% respectively compared with the soil between hedgerow steeps. 2) The silt con- centration of soil in hedgerow systems were correlated positively and highly significantly (P < 0. 01) with the soil porosity, water content, soil saturated water conductivity, anti-erodibility, anti- scouribility and soil water stable aggregates content, and correlated negatively with soil bulk density. 3) The silt concentration of soil in hedgerow systems were positively correlated with soil nutrients, containing total and exchangeable nitrogen, total and exchangeable phosphorus, total and exchangeable potassium, and cation exchangeable capacity.
不确定条件下应急管理人力供应链多功能资源配置鲁棒优化问题
朱雷,,汪明
系统工程理论与实践 , 2015,
Abstract: ?在紧急甚至灾难状态下,应急管理物资及人力需求都是爆发性的,为了满足应急状况的不确定需求,实现应急人力的合理管理和配置,借鉴成熟的供应链理论,强化应急管理人力供应链的协调配置能力有很大的理论及现实意义.本文简述了人力供应链的发展,重点讨论应急状态下连续性的人力服务需求.需求到来及其长度都是不确定的,多能力的专业人员应当被合理配置以优化服务.在本文中,我们提出了一个不确定条件下的网络优化模型,强调了多能力专业人员的资源分配.随机规划模型及鲁棒优化技术将被运用来处理不确定需求及网络优化,我们也将讨论其他特殊情况如服务取消,服务延长,提前结束等,我们的模型将有较为普遍的适应性.
三峡库区植物篱系统土壤有机质分布及其与土壤 理化性质的关系
Soil Organic Matter Distribution and the Relationship between Physicochemical Properties of Hedgerow Systems in the Three Gorges Reservoir Area
 [PDF]

, 张洪江, 陈奇伯, 周红芬
Open Journal of Soil and Water Conservation (OJSWC) , 2013, DOI: 10.12677/ojswc.2013.11005
Abstract: 在调查分析长江上游现有坡耕地植物篱的配置方式、生长状况和室内分析植物篱系统内土壤有机质和土壤理化性质分析的基础上,对3种植物篱系统中土壤有机质分布特征及其与土壤理化性质的关系进行了研究,结果表明:坡耕地系统中不同位置土壤有机质含量存在显著差异,3种植物篱带间坡耕地土壤有机质平均含量为6.33 g?kg?1,植物篱带上、带内和植物篱带下土壤有机质含量比植物篱带间坡耕地土壤有机质平均含量分别增加27.9%67.3%31.6%;植物篱系统内土壤有机质与土壤孔隙度、土壤含水量、饱和导水率、土壤抗冲指数、土壤抗蚀指数、水稳性团聚体极显著正相关,而与土壤容重呈显著负相关关系。土壤有机质与土壤全氮、水解氮、土壤全钾、有效钾、全磷、有效磷和阳离子交换量具有极显著正相关关系。
 To achieve the soil organic matter distribution characters and the relationship between physicochemical properties of hedgerow systems in the Three Gorges reservoir area, soil organic matter and physicochemical properties of soil collected from different position in hedgerow systems with different species were tested, and the coefficient between soil organic matter and physicochemical properties was analyzed. The result revealed that 1) the mean value of soil organic matter of the steep land between hedgerows was 6.33 g?kg?1, and the soil organic matter of soil before, within and behind the hedgerows were higher than that of soil in steep land between hedgerows, by 27.9%, 67.3% and 31.6% respectively. 2) The organic matter of soil in hedgerow systems was correlated positively and highly significantly (P < 0. 01) with the soil porosity, water content, soil saturated water conductivity, anti-erodibility, anti-scouribility and soil water stable aggregates content, and correlated negatively with soil bulk density. In addition, the organic matter of soil in hedgerow systems was highly correlated with soil nutrients, containing total and exchangeable nitrogen, total and exchangeable phosphorus, total and exchangeable potassium, and cation exchangeable capacity.
大突发事件对原油价格的影响
张珣,余乐安,,汪寿阳
系统工程理论与实践 , 2009,
Abstract: 基于结构性断点检验和常收益事件分析模型,分析了伊朗革命、海湾战争和伊拉克战争三次重大突发事件对原油价格的影响. 结果表明:三次事件均对原油价格走势产生了显著影响,其中伊朗革命和伊拉克战争导致了油价结构性断点的产生.三次战争对油价的影响模式均满足危机模型.
用卡尔曼滤波分光光度法测定安钠咖注射液的含量
张璀,,夏重玉,李树英
药学学报 , 1988,
Abstract:
基于p2p网络的大规模视频直播系统
光?,张萌?,,杨士
软件学报 , 2007,
Abstract: 介绍了一种基于p2p(peer-to-peer)网络的大规模视频直播系统gridmedia.该系统采用gossip协议构建无结构的应用层覆盖网络,每个节点可以独立地选择自己的伙伴节点.在覆盖网络上,每个节点通过一种推拉结合的流传输策略从邻居节点获取数据.与donet中的纯拉策略相比,推拉结合策略大幅度减小了终端用户观看视频的延迟,并有效降低了直播系统的控制开销.planetlab上的大量实验充分表明了该策略的有效性.gridmedia的原型系统通过300kbps的视频码流对2005年春节联欢晚会进行了全球互联网直播.晚会期间,全球范围内有超过500000人次通过系统观看了直播,最高在线人数达到了15239人,充分验证了系统的性能.
复合主拱圈加固石拱桥力学性态分析
,小刚,,韩雪,徐正
重庆交通大学学报(自然科学版) , 2010,
Abstract: :?从复合主拱圈加固石拱桥加固前后力学性态的角度,结合具体的实际加固工程,对加固前后主拱圈截面内力进行计算,阐述主拱圈截面强度和整体“强度-稳定”性提高率,验算新旧拱圈结合面抗剪承载力和新增结构对原结构的影响,提出一项基于承载力提高率的加固增强总体效果评价指标,以期对石拱桥加固设计方案比选、加固质量评定有一定的积极指导作用。
新疆雪莲水孔蛋白sikPIP1基因的克隆与功能分析
玉顺,刘逸泠,刘步仓,,
生物技术通报 , 2015, DOI: 10.13560/j.cnki.biotech.bull.1985.2015.09.013
Abstract: 利用PCR技术从已建立的新疆雪莲cDNA文库中克隆雪莲水孔蛋白基因sikPIP1,构建植物表达载体pBI121-sikPIP1,利用农杆菌介导法获得转基因烟草,PCR和RT-PCR检测证明该基因成功导入并得以转录,并对检测结果均为阳性的植株通过水分胁迫和温度胁迫进行抗旱性和抗寒性分析。结果显示:(1)克隆得到长为880bp,具有水孔蛋白特性的sikPIP1基因,完整ORF为840bp。(2)水分胁迫中,断水7d后转基因烟草生长表型明显优于野生型烟草,生理指标测定结果显示,转基因烟草的相对电导率和丙二醛含量均低于野生型烟草,相对含水量高于野生型烟草。(3)不同温度胁迫处理,转基因烟草表型显著优于野生型,特别是0℃以下低温胁迫,野生型烟草出现严重的萎蔫,而转基因烟草受伤害程度较轻;生理指标结果显示转基因烟草相对电导率、丙二醛含量低于野生型烟草。结果表明,转sikPIP1基因提高了烟草抗旱能力和抗寒能力。
Research on supply chain dynamic balanced scorecard based on fuzzy evaluation and Markov forecast techniques
基于模糊评估和马尔可夫预测的供应链动态平衡记分卡

ZHENG Pei,Kin Keung LAI,
郑 培
,

系统工程理论与实践 , 2008,
Abstract: 传统的供应链绩效评价方法大多属于静态评价,而实际上供应链是一个动态系统,需要使用动态的绩效评价方法来进行考量.为了适应动态联盟整体绩效评价之需要,把传统的四维平衡计分卡扩展为五维动态平衡计分卡,然后运用层次分析法(AHP)来捕捉重要绩效驱动指标的扰动对于供应链整体绩效评价的影响,去除对绩效评价贡献较小的指标.在此基础上,利用模糊综合评估方法计算出供应链在各个时期的绩效评价结果.最后,结合Markov预测理论的决策支持功能,给出了动态供应链未来的绩效评价结果及发展趋势.计算实例表明本文提出的动态供应链绩效评价模型是合理、有效的,能够为供应链的合理分析和决策制定提供依据.
A Dynamic Programming Model for Tax Collection and Payment Based on the Time Value of Tax Payment
基于税款时间价值的税企动态规划模型

LIU Jing-juan,LAI K K,
刘京娟
,

系统工程理论与实践 , 2006,
Abstract: In view of the current situation for tax payment and audit,we consider in this paper the time value of tax payment.We first prove that the penalty rate for late tax payment should be higher than bank loan rate when tax payment delay for a business follows a Poisson distribution.Subsequently,we set up a dynamic programming model to analyze the decisions of a tax collection agent and a tax paying business.Using backward induction,we obtain the taxpayer's optimal policy for tax filing and payment at different stages.Using analysis of elasticity,we derive that,when the penalty coefficient is fixed,the daily penalty rate for late tax payment should be lowered.Finally,suggestions are given to encourage corporations to pay their taxes in time.
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