Determination of the 129I transmutation rate and 129I(n, 2n)128I correction using gas mass spectrometry

Two groups of ¹²⁹I and ¹²⁷I targets were analyzed using a gas quadrupole mass spectrometer (QMS) to determine the transmutation rates via the melting method. Sodium iodide was chosen to make the target. The iodine composition in the ¹²⁹I targets is 82.7% ¹²⁹I and 17.3% ¹²⁷I. The transmutation rate of the ¹²⁹I(n, γ)¹³⁰I reaction was determined by measuring the ¹³⁰Xe with QMS. An equivalent corrective method was brought out to correct the ¹²⁹I(n, 2n)¹²⁸I branch which is interfered with by the ¹²⁷I(n, γ)¹²⁸I reaction. And the correction formula was deduced in theory. For very little ¹²⁸Xe from the ¹²⁹I(n, 2n)¹²⁸I reaction, the equivalent corrective method could not be suitable here. However, it is suitable for the mass of ¹²⁸Xe from ¹²⁹I(n,2n)¹²⁸I reaction that reaches the accurately detective level of the mass spectrometry.     

The influence of combined alignments on lateral acceleration on mountainous freeways: a driving simulator study

Combined horizontal and vertical alignments are frequently used in mountainous freeways in China; however, design guidelines that consider the safety impact of combined alignments are not currently available. Past field studies have provided some data on the relationship between road alignment and safety, but the effects of differing combined alignments on either lateral acceleration or safety have not systematically examined. The primary reason for this void in past research is that most of the prior studies used observational methods that did not permit control of the key variables. A controlled parametric study is needed that examines lateral acceleration as drivers adjust their speeds across a range of combined horizontal and vertical alignments. Such a study was conducted in Tongji University’s eight-degree-of-freedom driving simulator by replicating the full range of combined alignments used on a mountainous freeway in China. Multiple linear regression models were developed to estimate the effects of the combined alignments on lateral acceleration. Based on these models, domains were calculated to illustrate the results and to assist engineers to design safer mountainous freeways.     

运载火箭时序仿真测试系统设计

检测运载火箭地面测试设备的方法种类繁多,方法复杂,测试周期较长。设计一种运载火箭时序仿真测试系统,采用FPGA芯片的SOPC(可编程片上系统)技术,基于全双工USB 3.0控制芯片( CYUSB3014)完成上位机通信,单板模拟运载火箭飞行过程中64路时序系统发出的时序信号和时串信号,对不同测试需求的地面测试设备进行功能检测和故障诊断。具有方法简单,通用性好、精度等级高、通道数多的优点,能有效提高地面测试设备在测试任务中的测试效率。     

基于FPGA实现的PCI-I2S接口转换电路

提出了一种基于FPGA实现的PCI-I2S音频系统方法。通过在FPGA中将PCI软核、FIFO以及设计的接口电路等相结合,在FPGA上实现了PCI、I2C、I2S等多种总线,并且结合音频解码器实现了不同采样频率语音数据的传输以及播放功能。系统充分利用FPGA的片上资源及其可编程特性,减少了硬件电路的复杂度     

随钻分体巨型捞杯的研制和应用

新疆塔里木哈拉哈塘油田生产过程中,由于生产压差加大,产层压力快速下降,导致了地层垮塌出砂,严重影响了油井产能。因地层压力系数低,修井过程中井漏严重无法建立正常循环,冲砂后砂子无法通过钻井液循环携带至地面;常规捞砂工具一般不能钻磨,容易发生卡钻事故。针对哈拉哈塘油田的储层特征,结合常规捞砂工具的优缺点,研制了随钻分体巨型捞杯。利用钻井液循环过程中在杯口处流速陡然下降形成涡流,使得钻井液携带能力也大大减弱,从而使其中较重的碎物落入杯中并随起钻捞出。本文以哈11-4井和哈601-18井为例,简要介绍了随钻分体巨型捞杯在碳酸盐岩漏失层捞砂作业的成功运用。     

基于基本空间语言能力和中国人文属性的建筑设计教学改革

为解决中国当前建筑设计教学中存在的问题,研究借鉴国外建筑设计教学体系的最新发展,融入中国传统人文属性,设计一系列具有人文性,注重设计过程,富有设计教育针对性、可教授性的教学载体,将空间认识直接引入建筑学教学,以期通过空间语言的词汇、句法、结构的组织和人文浸润构建学生的专业能力。     

城市高老龄化地区社区养老设施现状及规划策略

新世纪以来,国家和北京市陆续出台的与人口老龄化相关的政策文件均明确了以社区为主导的养老模式。因此,摸清城市社区养老设施现状与老年人需求的规律,进而有针对性地提出规划战略迫在眉睫。研究以北京市朝阳区为例,通过对三个典型片区的调研发现,目前高老龄化地区养老设施普遍存在设施类型与数量短缺、配建规模偏低、功能不全、供需不平衡等问题,进而提出完善社区养老设施体系、调整社区养老设施配套标准、优化社区养老设施空间布局和应用物联网技术实现养老设施智能化的四大规划战略。     

邻里社区游园的营造--长青公园景观改造设计

作为上海浦东三林片区景观功能提升的重要工程,长青公园的整体改造项目具有着重要的意义和作用。在尊重三林传统文化、建设和谐邻里社区、提升公共绿地品质的大前提下,提炼传统民俗文化元素,向公众展示一个现代的、人文的、和谐的社区公园新形象,是公园改造设计的初衷。作为对原有长青公园的改造与升级,设计方案探索实践了“邻里中心”设计理念,在原有公园格局的基础上,从多种功能视角出发,运用多种设计手法,创建了一个充满人文文化底蕴、宜居的社区生活配套公园。     

Study on process and mechanism of laser drilling in water and air

This paper describes a particle expert system (PES) that was developed to improve particle classification for burrs, casts, and chips in the automotive production process. Image-processing techniques were deployed to extract particle information and remove noise from industrial filters and lighting systems. An advanced model of a particle classification algorithm (PCA) was built with 12 particle classes and a particle-expert-system (PES) algorithm was developed to train the PCA parameters to achieve the target success rate. The particle expert system will help the user locate the source of particles with high reliability and a stable success rate immediately after image processing and training the PCA parameters.     

预制减震墙板加固震损框架抗震性能试验研究

本文中提出先对震损框架进行局部修复,再采用预制减震墙板进行加固的预制减震墙板加固震损框架的方法,设计制作震损修复框架(RBF)、预制减震墙板加固震损框架(DWF)以及预制普通墙板加固震损框架(CWF)3榀足尺试件,对其进行拟静力加载试验,对比研究3个试件的滞回性能、承载能力、破坏形态以及延性等抗震性能。结果表明：对震损框架进行局部修复,再采用预制减震墙板对其进行抗震加固可提高震损修复框架的抗侧刚度、承载能力和屈服后的变形能力;预制减震墙板加固震损框架(DWF)滞回曲线稳定、饱满,其承载力衰减缓慢,具有良好的持续抵抗外荷载的能力,不改变震损修复框架结构的受力和破坏特征,其变形能力满足GB 50011—2010《建筑抗震设计规范》罕遇地震作用下1/50层间位移角的要求,具有良好的抗倒塌能力;预制减震墙板单元与框架间的拉结筋构造措施提高了结构的整体性,保证了预制减震墙板既定的摩擦滑移耗能机制的有效实现。