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低能离子束在植物种粒和微生物中的穿透深度 被引量:12
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作者 吕晓桂 罗辽复 《生物物理学报》 CAS CSCD 北大核心 2006年第1期57-61,共5页
计算了低能离子注入生物体中的穿透深度,考虑生物媒质为匀相多组元系统,求出了平均射程的一般理论公式,将其用于植物种粒和微生物中。以30keV的N+注入水稻种子和100keV的As+注入微生物细胞为例,计算了平均穿透深度,结果与实验资料一致... 计算了低能离子注入生物体中的穿透深度,考虑生物媒质为匀相多组元系统,求出了平均射程的一般理论公式,将其用于植物种粒和微生物中。以30keV的N+注入水稻种子和100keV的As+注入微生物细胞为例,计算了平均穿透深度,结果与实验资料一致。指出抽真空过程中水分蒸发及离子注入时的热效应和机械效应对植物种子结构的动态影响,可使穿透深度大大加大。 展开更多
关键词 离子注入 水分蒸发 匀相系统 匀相系统 射程
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Effects of friction variability on isolation performance of rolling-spring systems 被引量:1
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作者 魏标 王鹏 +3 位作者 杨添涵 戴公连 蒋丽忠 文颖 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期233-239,共7页
By taking a rolling-spring isolation system as the study object, the effects of the non-uniform distribution of rolling friction coefficient on its isolation performance were analyzed by a compiled computer program. T... By taking a rolling-spring isolation system as the study object, the effects of the non-uniform distribution of rolling friction coefficient on its isolation performance were analyzed by a compiled computer program. The results show that the errors associated with the structural maximum relative displacement, acceleration and residual displacement due to ignoring the friction variability sequentially grow. This rule is weakened by the spring action, however, the unreasonable spring constant will cause sympathetic vibration. Under the condition of large friction variability, in the calculation of the structural maximum relative displacement and acceleration, the friction variability should be considered. When the structural residual displacement is concerned, the variability of rolling friction coefficient should be fully considered regardless of the friction variability. 展开更多
关键词 rolling-spring structure seismic isolation rolling friction seismic performance
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Research on Evenness of Woollen Cashmere Yarn
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作者 徐先林 黄故 李培玲 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期522-527,共6页
Parameters influencing the evenness of the woollen cashmere yarn were analyzed, and fifty batches of yams with fineness of 38.5 tex were used to study the quality control parameters in relation to the evenness. Throug... Parameters influencing the evenness of the woollen cashmere yarn were analyzed, and fifty batches of yams with fineness of 38.5 tex were used to study the quality control parameters in relation to the evenness. Through statistical analysis, the models of yarn evenness were built. Moreover, the relationship between the evenness of spinning yarn and roving yarn was also investigated. The results showed that a positive correlation existed between them, and the mount of thin place per kilometer was the most important factor which could influence the evenness of woollen cashmere yam. The influence of the amount of neps and thick place on the yam evenness was indistinctive. The conclusions obtained would be helpful to improve the precontrol ability on yarn evenness. 展开更多
关键词 woollen cashmere yarn yarn evenness correlation
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A brief analysis of the phase transitions and the overall correlation behavior in non uniformity computer network
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作者 Liu Zhijun Pu Xiaowei 《International Journal of Technology Management》 2014年第5期10-12,共3页
With the developing of the computer, the network is more and more liked by the users. It has become an indispensable part of the living and production. However, with the expanding of network scale, there have been som... With the developing of the computer, the network is more and more liked by the users. It has become an indispensable part of the living and production. However, with the expanding of network scale, there have been some problems in the operation of the network system. Most of people lack of understanding on these issues, so they couldn' t handle them well. Some people use the theory of phase transitions to explain the power law phenomena in computer network. But it only start from the theory, but ignores the correlation of network nodes. The lack of holistic thinking mode, make the development of computer network get into a stray area. This paper started from the phase transition theory, elaborated the connotations of phase transformation and the overall correlation, and described the problems about them. 展开更多
关键词 Computer network phase transitions theory the overall association the non uniformity
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Asymptotics of the quantization errors for in-homogeneous self-similar measures supported on self-similar sets
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作者 ZHU SanGuo 《Science China Mathematics》 SCIE CSCD 2016年第2期337-350,共14页
We study the quantization for in-homogeneous self-similar measures μ supported on self-similar sets.Assuming the open set condition for the corresponding iterated function system, we prove the existence of the quanti... We study the quantization for in-homogeneous self-similar measures μ supported on self-similar sets.Assuming the open set condition for the corresponding iterated function system, we prove the existence of the quantization dimension for μ of order r ∈(0, ∞) and determine its exact value ξ_r. Furthermore, we show that,the ξ_r-dimensional lower quantization coefficient for μ is always positive and the upper one can be infinite. A sufficient condition is given to ensure the finiteness of the upper quantization coefficient. 展开更多
关键词 condensation system in-homogeneous self-similar measures quantization coefficient quantizationdimension
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A Parallel Line Segment Intersection Strategy Based on Uniform Grids
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作者 ZHOU Qin ZHONG Ershun HUANG Yaohuan 《Geo-Spatial Information Science》 2009年第4期257-264,共8页
The line segment intersection problem is one of the basic problems in computational geometry and has been widely used in spatial analysis in Geographic Information Systems (GIS). Lots of traditional algorithms study... The line segment intersection problem is one of the basic problems in computational geometry and has been widely used in spatial analysis in Geographic Information Systems (GIS). Lots of traditional algorithms study the problem in a serial environment. However, in GIS, a spatial object is much more complicated and is considered to be always composed of multiple line segments, and one line segment connects another line segment at its endpoint. On the other hand, along with the advances made in computer hardware, more and more personal computers have multiple cores or CPUs equipped. Thus, to make full use of the increasing computing resources, parallel technique is applied as one of the most available methods. Apparently, the traditional algorithms should be improved to take advantage of the technologies. Under these circumstances, based on the modified uniform grid algorithm, which is adapted to dealing with spatial objects in GIS, this paper proposes a parallel strategy in a shared memory architecture. Also, experimental results are given in the final part of this paper to demonstrate the efficiency this strategy brings. 展开更多
关键词 line-segment intersection parallel computing GIS
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