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Search Results: 1 - 10 of 56056 matches for " 胡青龙 "
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三维空间中一类波动方程渐近理论新探
青龙
四川师范大学学报(自然科学版) , 2000,
Abstract: 研究了三维空间中一类半线性波动方程解的渐近理论,在古典空间C2中得到了形式近似解的合理性在长时间t∈0,|ε|-12-k(p-1)(ε充分小,0<2-k(p-1)<1,03)内成立,和以前的相关结果比较,得到的时间阶函数更优化了.更多还原
关于极大Euler 3-序列(d_p=4)的平面实现
青龙
四川师范大学学报(自然科学版) , 1999,
Abstract: 研究d1-dp=3且dp=4即7k16k25k34k4的极大Euler3序列是否平面序列的问题;对p=8至14的65种极大Euler3序列(dp=4)进行了研究,其中52种序列为平面序列,给出了相应的平面实现;9种序列为非平面序列,并给出了相应的证明
非线性摄动电报方程初值问题的渐近理论
陈宗荣,青龙
四川师范大学学报(自然科学版) , 1998,
Abstract: 对一类二阶半线性摄动电报方程,给出了一个渐近方法,证明了解的渐近理论及形式近似解的合理性都在时间变量无穷大时(0≤t≤O(|ε|-1))成立,并推广了赖绍永的工作[应用数学及力学,1997,18(7)611~616].
一维空间中半线性波方程的整体解
青龙,李志洪
四川师范大学学报(自然科学版) , 2001,
Abstract: 研究Cauchy问题utt-uxx=εF(u),t>0,0
一类Boussinesq方程Cauchy问题的整体解
王颖,青龙,赖绍永
四川师范大学学报(自然科学版) , 2003,
Abstract: 研究如下带阻尼Boussinesq方程初值问题utt-2butxx=-αuxxxx+uxx+β(f(u))xx,u(x,0)=εφ(x),ut(x,0)=εψ(x)的整体解的存在性.其中x∈(-∞,+∞),α、β是正常数,β是实数,ε是小参数,f∈C∞.当α>b2时,得到了文献(DifferentialandIntegralEquations,1996,9(3)619~634.)的适定性理论.更多还原
水反应金属燃料发动机初步试验
凡?,焦绍球?,张为华?,建新?,缪万波?,青龙
推进技术 , 2008,
Abstract: 介绍了水反应金属燃料发动机试验系统,提出了水燃比、工作压强及试验燃烧效率计算方法,为试验设计和发动机性能评价提供了依据。对水反应金属燃料发动机进行了试验研究,并根据试验结果对药柱组分、发动机结构及供水系统进行了改进。试验表明,中等含量金属燃料加水后可稳定燃烧,通过增加燃料中镁含量、稳定进水流量和增加补燃室长度等措施,可有效提高发动机燃烧效率。
参照群体规范影响下的吸引效应研究
The Normative Impact of Reference Group on Attraction Effect

青龙
- , 2015,
Abstract: 吸引效应颠覆了经典偏好理论对偏好的描述,具有重大的理论价值及营销实践意义,但其研究情景需要进一步拓展。从社会影响视角出发,研究参照群体规范以选择集中的不同产品为参照点时吸引效应的变化,研究结论显示,参照群体规范可以显著影响吸引效应的效应值大小。
Attraction effect is a new definition of preference theory, which is of great theoretical value and of great significance in marketing practice. But its diversity scenes need further researching. In this paper, we discuss the variation of attraction effect when reference point changed with the perspective on reference group effect, according to the view of normative influence of reference group. It is proved that normative influence of reference group is a crucial variable to attractive factor.
一种无第三方参与的匿名指纹方案
青龙,杨波
电子学报 , 2005,
Abstract: 基于类ElGamal加密体制,本文提出了一种无第三方参与的匿名数字指纹方案.在无第三方参与的情况下,该方案巧妙实现了销售商对匿名用户的身份认证,确保了只有合法注册用户才能得到数字产品;同时,销售商在收缴到盗版拷贝时,无须用户的参与就能够追踪出真正的盗版者.此外,方案还具备不可联系性,防诬陷性.方案的安全是基于解离散对数为困难问题.
较大尖削度原木旋切方式的改进研究
李哲锋,青龙
- , 2017, DOI: 10.13360/j.issn.2096-1359.2017.05.004
Abstract: 对较大尖削度原木或小径材进行旋切加工时, 不可避免地会发生在平行于切削方向且垂直于切削平面内的单板切削方向与木材纤维方向形成夹角的现象, 这在一定程度上会增大原材料的损耗, 同时,木材纤维的走向也会影响制品的性能。为提高木材的利用率并保证所制产品的质量, 采用倾斜安装旋切刀片的切削方式进行单板旋切加工, 并测定单板所制胶合板和单板层积材的静曲强度和弹性模量。结果表明:边材部位纤维锥角的变化范围小于心材部位; 旋切刀在平行安装方式与倾斜安装方式下进行切削, 纤维锥角的变化趋势不变, 但后者更小。旋切刀倾斜安装的方式可以提高原木边材部位切削单板的质量, 对单板的静曲强度、单板层积材和薄单板所制胶合板的性能都有较好的改善效果。
When peeing the logs with large taper or small diameter, an angle between the wood grain direction and tangential plane on the side surface of the peeling veneer was unavoidable, which could increase raw material waste and worsen the product properties due to the wood grain orientation. In order to improve the utilization of wood and the quality of veneers, this study used a method that the blade had an angle with the log axle in the veneer peeling process. The modulus of rupture(MOR)and modulus of elastic(MOE)of the plywood and laminated veneer lumber(LVL)made from these veneers were examined. The results showed that the variation range of fiber taper angle for sapwood was smaller than that of heartwood. For different peeling methods resulted from the paralleled and oblique installation of the cutters, the change trend of fiber taper angle was stable although the taper angle resulted from the later installation way was smaller. The results of mechanical analysis showed that the MOR of the plywood and the LVL that made from the veneers peeled by the oblique cutter were higher than those peeled by paralleled cutter. No significant difference in the MOE of the plywood and LVL was found between these two methods. It was concluded that the oblique installation method could improve the quality of peeling products made from sapwood and improve the MOR of the LVL and plywood that made of these veneers
复合绝缘子在输电线路防污闪技术中的应用
Application of Composite Insulators Used in the Technology of Anti-Flashover in Transmission Lines
 [PDF]

青龙, 许元帅, 赵纪宗, 许园园
Smart Grid (SG) , 2014, DOI: 10.12677/SG.2014.43015
Abstract:

电力系统运行中,高压输电线路绝缘子污闪是一种常见的事故,其对于输电线路的安全运行以及电力系统安全运行有着非常重要的影响。随着输电线路的防污闪技术研究不断深入,清扫积污、调整爬电距离、使用防污闪涂料、采用复合绝缘子等技术应运而生。其中复合绝缘子以其优良的抗污特性,被广泛应用于防污闪技术中。本文综述了绝缘子污闪的机理、输电线路防污闪措施、合成绝缘子结构特点、优良性能,及在其使用过程中的常见问题。
In the operation of power system, insulator flashover is a common accident which has serious effect on high voltage transmission line. Some methods, such as cleaning contamination, creepage distance adjustment, using anti-flashover coating and using composite insulators, have been emerged with the development of anti-flashover technology. Among those methods, the composite insulators were widely used because of its excellent stain resistance characteristics. This paper reviews the mechanism of flash insulator pollution, measures of anti-flashover, structural characteristics and excellent performance of composite insulators. Finally, frequently asked questions in the course of its use were discussed.

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