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51.
银行尾箱智能交接系统是以RFID射频技术、有线网络和无线网络技术为依托而建立的。实现银行尾箱交接业务链信息的实时快速采集和上传,尾箱信息随时读取,提供安全可靠的押运人员身份认证,运钞押运节点过程动态监控、审计与监督管理,实现银行尾箱管理的自动化和电子智能化。 相似文献
52.
针对RoboCup中型组足球机器人比赛中光照变化会使颜色发生色彩漂移,影响颜色识别的准确性问题,提出一种基于光照变化补偿的颜色识别方法。该方法首先利用球的历史信息预测球的位置,然后在较小的区域内用基于色调直方图反向投影的方法找到球后,通过球的亮度直方图的变化计算出光照变化率,用于动态补偿颜色查找表。实验表明该方法能提高颜色识别的光照自适应性。 相似文献
53.
为探究不同土性地基的SSI效应对层间隔震结构影响机理与动力响应规律,选取一个典型层间隔震结构,对其简化并制作缩尺模型,采用振动台试验的方法,分别在硬土、软土这两种地基上单向输入4条地震波来研究模型的动力响应。结果表明:土体具有明显的放大效应,随着地基土由硬变软,隔震结构周期延长倍数降低。隔震结构在硬土地基上能发挥较好的减震效果,而软土地基上减震效果明显减弱。软土地基上塔楼的动力响应较硬土地基增大,塔楼容易成为薄弱部位,其抗震设计应重点关注。 相似文献
54.
55.
Hyuntae ParkAuthor VitaeHyejeong HongAuthor Vitae Sungho KangAuthor Vitae 《Computer Networks》2012,56(1):231-243
Due to a tremendous increase in internet traffic, backbone routers must have the capability to forward massive incoming packets at several gigabits per second. IP address lookup is one of the most challenging tasks for high-speed packet forwarding. Some high-end routers have been implemented with hardware parallelism using ternary content addressable memory (TCAM). However, TCAM is much more expensive in terms of circuit complexity as well as power consumption. Therefore, efficient algorithmic solutions are essentially required to be implemented using network processors as low cost solutions.Among the state-of-the-art algorithms for IP address lookup, a binary search based on a balanced tree is effective in providing a low-cost solution. In order to construct a balanced search tree, the prefixes with the nesting relationship should be converted into completely disjointed prefixes. A leaf-pushing technique is very useful to eliminate the nesting relationship among prefixes [V. Srinivasan, G. Varghese, Fast address lookups using controlled prefix expansion, ACM Transactions on Computer Systems 17 (1) (1999) 1-40]. However, it creates duplicate prefixes, thus expanding the search tree.This paper proposes an efficient IP address lookup algorithm based on a small balanced tree using entry reduction. The leaf-pushing technique is used for creating the completely disjointed entries. In the leaf-pushed prefixes, there are numerous pairs of adjacent prefixes with similarities in prefix strings and output ports. The number of entries can be significantly reduced by the use of a new entry reduction method which merges pairs with these similar prefixes. After sorting the reduced disjointed entries, a small balanced tree is constructed with a very small node size. Based on this small balanced tree, a native binary search can be effectively used in address lookup issue. In addition, we propose a new multi-way search algorithm to improve a binary search for IPv4 address lookup. As a result, the proposed algorithms offer excellent lookup performance along with reduced memory requirements. Besides, these provide good scalability for large amounts of routing data and for the address migration toward IPv6. Using both various IPv4 and IPv6 routing data, the performance evaluation results demonstrate that the proposed algorithms have better performance in terms of lookup speed, memory requirement and scalability for the growth of entries and IPv6, as compared with other algorithms based on a binary search. 相似文献
56.
The irrigation in regions of brackish groundwater in many parts of the world results in the rise of the water-table very close to the groundsurface. The salinity of the productive soils is therefore increased. A proper layout of the ditch-drainage system and the prediction of the spatio-temporal variation of the water table under such conditions are of crucial importance in order to control the undesirable growth of the water-table. In this paper, an approximate solution of the nonlinear Boussinesq equation has been derived to describe the water-table variations in a ditch-drainage system with a random initial condition and transient recharge. The applications of the solution is discussed with the help of a synthetic example.Notations
a
lower value of the random variable representing the initial water-table height at the groundwater divide
-
a+b
upper value of the random variable representing the initial water-table height at the groundwater divide
-
h
variable water-table height measured from the base of the aquifer
-
K
hydraulic conductivity
-
L
half width between ditches
-
m
0
initial water-table height at the groundwater divide
-
N(t)
rate of transient recharge at time t
-
N
0
initial rate of transient recharge
-
P
N
0/K
-
S
Specific yield
-
t
time of observation
-
t
0
logarithmic decrement of the recharge function
-
T
Kt/SL
-
x
distance measured from the ditch boundary
-
X
x/L
-
Y
h/L
- Y
mean of Y
- Y
Variance of Y 相似文献
57.
文章提出了在不同操作系统以及不同平台上获取MAC地址的方法。以目前比较典型的两种操作系统:UNIX操作系统和WINDOWS操作系统为例,阐述了具体方法,并给出了相应的C/C++语言读取MAC地址的实现程序。 相似文献
58.
计算机网络和Internet网络中,存在着的MAC(物理地址)和IP地址,网络双方的通信必须按照地址来进行,本文详细对介绍网络中的MAC和IP地址的知识并对它们的一些典型的应用进行了阐述。 相似文献
59.
The nonlinear Boussinesq equation is used to understand water table fluctuations in various ditch drainage problems. An approximate solution of this equation with a random initial condition and deterministic boundary conditions, recharge rate and aquifer parameters has been developed to predict a transient water table in a ditch-drainage system. The effects of uncertainty in the initial condition on the water table are illustrated with the help of a synthetic example. These results would find applications in ditch-drainage design.Notation
A
/ tanh t
-
a
lower value of the random variable representing the initial water table height at the mid point
-
a+b
Upper value of the random variable representing the initial water table height at the midpoint
-
B
tanh t
-
C
4/
-
h
variable water table height
- h
mean of the variable water table height
-
h
m
variable water table height at the mid point
- h
m
mean of the variable water table height at the mid point
-
K
hydraulic conductivity
-
L
half spacing between the ditches
-
m
0
initial water table height at the mid point
-
N
Uniform rate of recharge
-
S
specific yield
-
t
time of observation
-
x
distance measured from the ditch boundary
-
(4/SL)(NK)1/2
-
(L/4)(N/K)1/2
-
dummy integral variable 相似文献
60.
近年来带锂离子电池的可移动式LED充电台灯引发爆炸、起火、燃烧等质量安全事件时有发生,为充分了解该类产品的质量状况,确保消费者的生命财产安全。本文选取了电商平台上销售的30批次样品进行试验、分析和评估,结果显示:样品存在标记缺失、结构不合格、耐热不合格、电池外部短路不合格等质量安全风险。依据国家相关的风险评估标准,将该类产品不同的监测项目应进行风险等级评划分,并针对风险等级程度对产品的质量提升要求提出了相关处置建议。 相似文献