Transmission and Reflection of Water-Wave on a Floating Ship in Vast Oceans

In this paper, we study the water-wave flow under a floating body of an incident wave in a fluid. This model simulates the phenomenon of waves abording a floating ship in a vast ocean. The same model, also simulates the phenomenon of fluid-structure interaction of a large ice sheet in waves. According to this method. We divide the region of the problem into three subregions. Solutions, satisfying the equation in the fluid mass and a part of the boundary conditions in each subregion, are given. We obtain such solutions as infinite series including unknown coefficients. We consider a limited number only of the coefficients by truncating the infinite series and satisfy the remaining boundary conditions approximately. Numerical experiments show that the results are acceptable. Tables are given along with the graph of the system of the resulting streamlines and the dynamical pressure acting on the obstacle. The drawn system of streamlines shows the correctness of the solution and the pressure is maximum on the side facing the upstream extremity of the channel. The same procedure can be adequately applied for problems with more complicated geometry and other phenomenon can thus be simulated.     

Hotelling's T2 control charts with fixed and variable sample sizes for monitoring short production runs

Short production runs are common in enterprises that require a high degree of flexibility and variety in manufacturing processes. To date, past research on short production runs has little focus on the multivariate control charts. In view of this, fixed sample size (FSS) and variable sample size (VSS) Hotelling's T² charts are designed to monitor the process mean when the production horizon is finite. Optimal parameters to minimize the out‐of‐control (1) truncated average run length (TARL) and (2) expected TARL (ETARL) are provided such that the in‐control TARL is equal to the number of inspections (say I). The numerical study considers the run length performances of the FSS and VSS T² short‐run charts for both known and unknown shift sizes. The VSS T² short‐run chart performs well in swiftly detecting various mean shifts in comparison with the FSS T² short‐run chart. Additionally, the VSS T² short‐run chart is superior to the FSS T² short‐run chart, in terms of the truncated standard deviation of the run length, expected truncated standard deviation of the run length, probability that the chart signals an alarm within the I inspections, ie, P(I) and expected P(I). A case study on the impurity profile of a crystalline drug substance illustrates the implementation of the VSS T² short‐run chart.     

Detecting the process changes for multivariate nonlinear profile data

In profile monitoring for a multivariate manufacturing process, the functional relationship of the multivariate profiles rarely occurs in linear form, and the real data usually do not follow a multivariate normal distribution. Thus, in this paper, the functional relationship of multivariate nonlinear profile data is described via a nonparametric regression model. We first fit the multivariate nonlinear profile data and obtain the reference profiles through support vector regression (SVR) model. The differences between the observed multivariate nonlinear profiles and the reference profiles are used to calculate the vector of metrics. Then, a nonparametric revised spatial rank exponential weighted moving average (RSREWMA) control chart is proposed in the phase II monitoring. Moreover, a simulation study is conducted to evaluate the detecting performance of our proposed nonparametric RSREWMA control chart under various process shifts using out‐of‐control average run length (ARL₁ ). The simulation results indicate that the SREWMA control chart coupled with the metric of mean absolute deviation (MAD) can be used to monitor the multivariate nonlinear profile data when a common fixed design (CFD) is not applicable in the phase II study. Finally, a realistic multivariate nonlinear profile example is used to demonstrate the usefulness of our proposed RSREWMA control chart and its monitoring schemes.     

方向高频保护的动作行为分析：第一部分：复杂系统的复故障计算

方向高频保护高压和超高压输出电线路的主要保护方式,其动作性能对电力系统的安全运行影响甚大。     

深层搅拌法加固泥炭质土的效果

220kV草──海线碧鸡关段,地层主要为第四系滨湖相及湖沼相沉积的软土,采用深层搅拌法加固软土地基。针对泥炭质土的物理力学特性,通过室内试验,提出应用特殊的加固配方,才能达到预期的加固效果及最佳经济效益。     

一种新型变电站综合自动化系统方案

采用面向对象的设计思想,提出了一种新型的变电站综合自动化系统结构。同时,本文还提出了以继电保护为核心,以变电站二次系统为整体优化目标的变电站综合自动化系统设计思想。着重以２２０ｋＶ变电站为例,设计出贯彻该思想的变电站综合自动化系统方案。     

电磁继电器的电磁干扰现象与抑制方法

介绍了电磁继电器的电磁干扰现象及产生的原因,论述了抑制电磁干扰的技术措施以及电磁继电器抗扰度测试的内容、测试方法,对于研制和开发具有电磁兼容性的高可靠性继电器及使用继电器的电子、电气设备,提高电子、电气设备和系统抗电磁干扰的能力,具有重要的意义。     

大型发变组集成电路保护的微机自动检测装置研制

对一套大中型发电机—变压器组的继电保护装置进行全面的测试是一项必须而复杂又费时的工作,ＸＨ０１型微机自动检测装置是一种基于单片机的先进的自动测试工具,借助于此装置,继电保护工作者可以高效而可靠地对保护装置进行全面的测试和分析,对保护的性能作出评价。本文简要介绍了自动检测装置的硬件设计和软件设计,并对装置的基本工作原理做了比较详细的论述。     

河北南网继电保护异常停运统计分析

根据近两年来河北南网220kV系统继电保护装置异常停运的统计资料,就不同类型装置的数据进行了对比,深入细致地分析了造成保护装置故障的原因。提出了减小装置的故障率、缩短故障处理时间的具体措施。     

直埋敷设供热管网中井室固定墩受力分析

分析直埋敷设供热管网中井室及固定墩的受力状态及其相互间的位置关系,将井室和固定墩结合为一体进行设计,并给出了井室固定墩的力学方程和设计方法。