MPLS网络带宽配置的Hose模型及优化算法

服务质量(QoS)和流量工程(TE)是在当前网络中提供实时应用业务的两项重要技术.多协议标记交换(MPLS)在IP网QoS提供和TE实现中起了关键作用.本文首先介绍了Hose模型,分析了MPLS网采用该模型提供多种VPN业务的流量工程问题,提出了MPLS网采用该模型提供多种VPN业务的最优带宽配置算法,给出了相关的优化模型和实例,实例优化结果表明该方法能在确保业务的QoS要求并且网络开销增加较少的情况下,有效地均衡网络负荷.

Hose不确定模型下一种新的动态选路算法研究

该文讨论了全连接结构的光交换网络在Hose不确定模型下的动态选路问题,并基于Valiant负载平衡机制,提出了一种新的动态选路算法--.分配系数可调的负载平衡选路算法(Load Balancing with Adjustable Distribution Fraction,LBADF)。LBADF算法根据网络中各条链路上空闲光路的数目对Valiant负载平衡机制中的分配系数进行动态的调整,从而达到优化网络性能的目的。计算机仿真表明LBADF算法相对于分配系数恒定的VLB算法具有更小的全网呼损率,同时也相应地降低了全网中所有节点对的最大呼损率。

Fuzzy PID control system for hose pulse experiment based on LabVIEW

The hose pulse testing bench generally uses electro-hydraulic servo system. It occupies little space, tracks signals fast and has simple structure, and therefore it is widely used in industrial control field. However, there are lots of problems such as little accuracy and instability caused by slow response of hydraulic and various interference factors. Simple proportional integra- tion derivatiation （PID） control method of traditional pulse bench is simple in principle, but it is difficult in parameter adjust- ment. According to the special requirements of the control system, a PID method based on fuzzy control is proposed in the pa- per. This method not only retains the advantages of the conventional control system, but also ameliorates the drawbacks of parameter uncertainty, instability and lag. It has been testified that the method is practicable and can improve the precision and adaptation.

Modeling Method and Control Strategy for Hose-Drogue Aerial Refueling System

Conventional method for hose-drogue model of aerial refueling system is known to be complex due to the flexible body of hose.And as reported,drogues are unstable in atmospheric turbulence,which greatly decreases docking success rates.This paper proposes a dynamic model for a hose-drogue aerial refueling system based on Kane equation and rigid multi-body dynamics,and analyzes its performance.Furthermore,the nonlinear dynamic model is linearized at the equilibrium point and simplified from full order to 2 nd order.Based on the simplified 2 nd order model,active control strategies,including proportion integral derivative(PID)and liner quadratic regulator(LQR)control laws,are designed to inhibit the pendulum movement of drogue due to,atmospheric turbulences.Numerical simulation results show the significant correctness of the proposed dynamic model by steady-state drag and balance position of drogue when the tanker flights under different conditions.Moreover,the steady state position error varies within 1 cm,thanks to either controller,when the drogue suffers from moderate-level atmospheric turbulences.Further,the PID controller exhibits better control effect and higher control precision than LQR controller.

Fluid-solid interaction of resistance loss of flexible hose in deep ocean mining

The resistance loss of transportation was studied and the influences of buoyancy layout,mineral content and elastic modulus of flexible hose were investigated based on three-dimensional finite element model of fluid-solid interaction by MSC.MARC/MENTAT software.The numerical results show that the resistance losses increase with the increase of mineral content Cv and velocity of internal fluid v and decrease with the increase of elastic modulus E of flexible hose.The buoyancy layout and the velocity of internal fluid have greater impacts on the resistance losses than the elastic modulus of flexible hose.In order to reduce the resistance losses and improve the efficiency of the deep-ocean mining,Cv and v must be restricted in a suitable range (e.g.10%-25% and 2.5-4 m/s).Effective buoyancy layout (such as Scheme C and D) should be adopted and the suitable material of moderate E should be used for the flexible hose in deep-ocean mining.

Finite element analysis of high-pressure hose for radial horizontal wells in coalbed methane extraction

Based on the serial-parallel model of single-layer board and the lamination theory, the forces exerted on different layers of the high-pressure hose and the resulting deformations were analyzed when the hose was radially stretched. An equation was proposed to calculate the anisotropic elastic constant of the composite layer with the wound steel wires. Furthermore, the finite element analysis （FEA） model of the high-pressure hose was established, followed by a simulation of the forces that act on different layers, and their deformations. The simulation results show that the stress imposed on the inner reinforced layer and external reinforced layer of the high-pressure hose are approximately 150 MPa and 115 MPa, respectively, in the presence of inner pressure. The stress of the rubber coating and polyethylene coating is lower. The lowest stress occurs on the inner surface of the high-pressure hose and the rubber coating between the two composite layers. The deformation of the rubber layer in the inner surface of the high-pressure hose decreases gradually along the radial direction from the inner surface to the external surface. The deformation of the reinforced composite layer is less than that of the external surface of the rubber coating. The equivalent stress of the reinforced composite layer is higher than that caused by the inner pressure, due to the presence of both inner pressure and axial tension.

Thermal-Fluid-Structure Coupling Analysis of Flexible Corrugated Cryogenic Hose

This work presents a numerical investigation of the thermal–fluid–structure coupling behavior of the liquid natural gas(LNG)transported in the flexible corrugated cryogenic hose.A three-dimensional model of the corrugated hose structure composed of multiple layers of different materials is established and coupled with turbulent LNG flow and heat transfer models in the commercial software ANSYS Workbench.The flow transport behavior,heat transfer across the hose layers,and structural response caused by the flow are analyzed.Parametric studies are performed to evaluate the impacts of inlet flow rate and thermal conductivity of insulation material on the temperature and structural stress of the corrugated hose.The study found that,compared with a regular operating condition,higher inlet flow velocities not only suppress the heat gain of the LNG but also lower the flow-induced structural stress.The insulation layer exhibits excellent performance in maintaining the temperature at the fluid–structure interface,showing little temperature change with respect to material thermal conductivity and ambient temperature.The simulation results may contribute to the research and design of the flexible corrugated cryogenic hoses and provide guidance for safer and more efficient field operations.

Influence of Biogeochemical Qualities of Shizuoka Water on the Degradation of PVC Shower Hose

Recently, it has been report of polyvinyl chloride (PVC) shower hoses becoming hard and brittle throughout the eastern and middle portion of Shizuoka Prefecture, Japan. No reason has been identified for this phenomenon. The affected cities are located at the paper industries area. We have collected the stiffed hoses attached to shower faucets and examined them for chemical changes. In addition, we have analyzed the water quality of 11 affected cities in Shizuoka in an attempt to establish a probable bio-physico-chemical chain reaction that could cause such hose degradation. According to elemental analysis, oxygen-containing carbon-based plasticizers may leach out of the hose. As a result, the hoses lost flexibility after one year of use in Shizuoka. The organic nutrient (1,4-dioxane) was identified by GC-MS and the utmost number of the heterotrophic bacteria has been detected by PCR-DGGE in the shower water of Shizuoka. The study concludes that the plasticizer disappeared from the stiffed hose and the special characteristics of water in Shizuoka, consisting of organic nutrients, can be used for heterotrophic bacterial growth as a energy source at the shower water temperature, which allows prompt utilization of the plasticizer by increasing abundant bacteria, causing the brittleness of the PVC hose.

动车组集便系统HOSE阀原理及常见故障浅析

以动车集便系统DN50 HOSE阀为研究对象,统计了其使用故障频率,对HOSE阀组成及工作原理进行了介绍,根据故障现象及故障频率,对DN50 HOSE阀进行了详细分析,结合分析结论及动车组检修标准,对DN50 HOSE阀的检修提出了建议。

宏观经济因素对HOSE股票价格指数的影响分析

在衡量六个宏观经济因素对胡志明证券交易所(HOSE)的股票价格指数的影响,包括通货膨胀,利率,M2货币供应量,VND/USD汇率,工业产值与外国直接投资。研究结果表明,通胀对HOSE的股价指数有负面影响;货币供应量,汇率,利率和工业产值对大多数股票价格指数都有积极影响。

Analysis of Damaged Silicon Rubber Hose

Recently, there have been many reports of silicon rubber (SR) hoses becoming brittle in juice factory within one month of purchase. The damage is a new phenomenon, and its cause is unknown. We have collected the damaged hoses attached to UHT sterilizer (ultra-high-temperature) in juice factory and examined them for chemical changes. In addition, we have analyzed the hose-washing chemicals (NaOH and HNO333) and the exposure UTH temperature have direct effect on the brittleness of the silicon hose in juice factory.

The Mechanical Behaviour of Rubber Hose Reinforced with Warp Knitted Fabric

A new process for the rubber hose reinforced with warp knitted fabric was introduced, and the relation between the inside pressure and the radial expansion ratio of four kinds of rubber radiator hose reinforced with warp knitted fabric was investigated. The result showed that the bursting pressure and the radial direction expansion ratio of the hose could meet the requirement of ISO4081 for auto radiator hose. A new model was built up to analyse the relation between the inside pressure and the radial expansion ratio of the hose based the reinforced fabric structure parameters and yarn properties.

The Experimental Research of the Control System of Flexible Hose Instability

The experimental control system of the superelastic hose instability is based on S7-200PLC as controller. The superelastic hoses are sealed at their both ends. The breakdown condition of that is taken as the object of study under different combined and working conditions. The upper computer of the experimental bench adopts MCGS configuration software. The test of experiment can meet the control and real-time monitoring of experimental platform conditions. In the experiment,we measure and monitor the data of temperature,tensile force,pressure and so on by the analog modules. During the process of experiment,the actuators like the solenoid valve and the motor are controlled by the switch. The paper describes that the constitution of experimental control system of the superelastic hose instability, control function and the achievement of monitoring condition. It is convenient to operate in the control system,the design cost is low,the man-machine interface is simple and understandable,and the experimental control system will be significant in bio-engineering and medical research.

Hose模型的虚拟专用网建造研究

虚拟专用网在共享的公共网络上提供了专用网络的连接。在考虑VPN提供服务的服务质量和灵活性的同时,希望通过适合的模型、通过链路复用的方式来节约成本。Hose模型可以很好地解决这一问题。文章主要讨论了VPN的几个不同的变种,并从其思想、实现和模拟结果等几个方面进行了探讨。文章系统地阐述了解决建VPN Hose时所遇到的问题,最后对它们进行了验证。文章在前部分讨论了几种树的路由,然后加上了一些算法和对不分裂、分裂路由作了线性约束。

VPN资源管理中Hose模型的研究

文章首先介绍了虚拟专用网(VPN)中提供服务质量(QoS)的两种模型(管道模型和软管模型)的基本概念,然后通过对两种模型的比较,给出了软管(Hose)模型的优点以及实现方式,最后给出了在Hose模型下最小生成树的求解的基本理论和实现算法。

LNG低温复合软管疲劳特性及参数化分析研究

LNG低温复合软管具有强度高、重量轻、柔韧性好等优点,可以满足恶劣海况下LNG的输送需求,但其结构复杂,且面临多种耦合载荷作用下的疲劳失效问题。首先建立了LNG低温复合软管的有限元模型,研究了复合软管在弯曲和内压载荷下的力学响应和弯曲疲劳寿命特性;然后改变螺旋钢丝直径、预紧间距、导程和纤维层数及摩擦系数等参数,对软管的弯曲疲劳寿命进行了参数化分析。结果表明预紧间距、导程和纤维层数对复合软管的疲劳损伤影响显著:预紧间距增大时,复合软管疲劳损伤先增大后减小;导程减小或者层数增加时,复合软管的疲劳损伤会明显减小。摩擦系数对疲劳损伤几乎没有影响。研究成果可为低温复合软管的结构设计提供理论参考。

燃气爆炸事故中软管物证案例分析及数据库建立

连接燃气源与灶具的软管是室内燃气爆炸事故现场中常见的一类物证,在事故调查中起到重要作用。该文以数起真实发生的室内燃气爆炸事故为案例,分析软管物证及痕证在事故调查及反演分析中的作用。结果表明,在某2起燃气爆炸事故案例中,通过分析软管形貌并测试软管特性参数,证实软管的玻璃化转变温度较高,现场温度远低于玻璃化转变温度导致的软管脆化开裂,是燃气泄漏的主要原因。在某起燃气爆炸火灾事故案例中,软管形貌完好无损,能够排除因软管连接的液化气罐泄漏导致的燃气爆炸事故。建立燃气爆炸事故中燃气软管痕证数据库,可向数据库内添加事故信息及软管图片信息,并检索数据库内已有信息。研究结果可为燃气爆炸事故调查及反演提供参考。

船艏装载原油外输软管动力影响因素分析

针对船艏装载原油外输软管安全作业问题,进行软管动力响应影响因素分析。基于集中质量法,建立船艏外输漂浮软管与穿梭油轮和FPSO的整体耦合动力分析模型,分析影响软管受力的影响因素,在此基础上确定软管受力最小的方案,并给出软管安全作业的环境工况。计算结果表明,在作业工况下设计漂浮软管管串长度为170.6 m,FPSO与穿梭油轮的距离为80 m,此时软管的有效张力最小。提出软管的极限作业工况范围为流速1.1 m/s,浪高7 m。研究提出的软管外输方案可为船艏外输漂浮软管设计提供参考。

导弹发射筒疏水系统改进设计

针对导弹发射筒疏水系统在实际使用时不能将筒底水排尽,需要人工清理的问题,在保持系统功能和布局基本不变的前提下,采用在筒底疏水口处加装疏水软管和吸入滤器的改进方案,设计了疏水软管和疏水法兰的连接方式,进行了吸入滤器结构设计及其与疏水软管连接设计。实际使用表明,改进后的系统能将筒底水基本排尽,提高了疏水效率。

FPSO外输软管安装方法分析

基于企鹅浮式生产储卸油装置(Floating Production Storage and Offloading,FPSO)项目,对比不同安装方法的优缺点,采用盘卷安装法完成外输软管安装。采用盘卷安装法进行FPSO外输软管安装在国内鲜有实例,详细描述该方法的施工顺序和要点,可为其他类似项目的外输软管安装提供参考。