活塞式热量表检定系统研究

提出了一种基于活塞式体积管的新型热量表动态检定技术.阐述了热量表检定装置的工作原理,设计了一种以工控机为控制核心,在VC++环境下进行数据自动采集及过程控制,实现检定参数实时准确测试的高精度热量表检定系统,从理论上分析了影响热量表热水流量检测系统的不确定度因素.研究表明,相对于现有的以质量法结合标准表法的热量表检定方法,本方案能有效提高热量表检定效率和精度.     

Boyer-Moore串匹配算法的改进

在分析Boyer-Moore (BM)算法的基础上,提出了BM算法的一个新的变形。其基本思想是在算法的预处理阶段,对扩展模式串Pa建立好后缀规则,其中：P是模式串,a是字母表中的任一字符,既加大了已匹配后缀的长度,同时隐含了Sunday算法的坏字符规则,从而获得更大的窗口跳跃距离。理论分析证明,该算法具有线性最差时间复杂度和亚线性平均时间复杂度,空间复杂度为O(m(σ+1))。实验结果表明,该算法的实际性能与BM算法相比有明显改善,尤其适合小字母表的情形。     

Correlation of the leakage flow rate with pressure changes in a clearance-sealed piston prover

Leakage flow rate is one of the most important contributions to the measurement uncertainty when measuring small gas flow rates with a clearance-sealed piston prover. Our previous study has shown that the systematic effects related to the change of the gas viscosity can be successfully corrected, whereas the effects related to the reproducibility of the leakage flow rate are poorly understood. This paper focuses on the interpretation and correction of the reproducibility related effects by analysing experimentally identified variations of the leakage flow rate and the gas pressure in the inclined piston prover. Small changes of the leakage flow in the inclined piston prover indicate that the position of the piston relative to the cylinder remains approximately the same. The obtained relationship between the leakage flow rate and the gas pressure below the piston led to the pressure-based correction of the leakage flow rate.     

关于提升装载机电子秤检定结果测量准确度的探讨

装载机电子秤广泛应用于货场、建筑工地,如何使检定结果准确可靠,本文对自动衡器检定装置标准器量值的管理方法进行了一些探讨。     

一个用于指针程序验证的自动定理证明器的设计与实现

对高可信软件需求的增加使得指针程序的验证成为近期的研究热点.指针逻辑作为Hoare逻辑的扩展,可以对指针程序进行精确的分析.介绍一个针对指针逻辑的自动定理证明器的设计和实现,描述了一些算法.实验结果表明,该定理证明器可以完全自动的证明用类C语言编写的关于单链表,双链表和二叉树的指针程序的验证条件,并生成机器可检查的证明.     

苏丹石油工程外输流量计量及在线标定橇的设计

介绍了苏丹石油工程中原油外输流量计量及自动标定系统橇块的设计.计量橇采用涡轮流量计作为流量检测仪表,流量信号上传到流量计量管理系统,从而实现流量的交接计量和在线自动标定.     

Uncertainty evaluation procedure and intercomparison of bell provers as a calibration system for gas flow meters

Many NMIs (national measurement institutes) and calibration laboratories worldwide use a bell prover as a calibration system for gas flow meters. The basic definition and procedure to estimate the bell prover uncertainty have been given in previous studies. After the announcement of a mutual recognition agreement (MRA) in 1998 by the BIPM (Bureau International des Poids at Mesures), many NMIs have needed to have more details of uncertainty evaluation procedure of the bell prover. In this study, more details of the test procedure of bell prover uncertainty are presented with a modification of position of the temperature and the pressure sensor to measure more exact values. The other modification is to use three precise guide rods with bearings to make the pressure in the bell more stable. Furthermore, a laser interferometer is used to enhance the measurement accuracy of the testing time and the traveling length of the bell. The uncertainty of the bells estimated by the procedure given in this study is 0.13% at the confidence level of 95%, rather than 0.17% of the previous one. Recently, the results of CCM.FF-K6, which is an international comparison of NMIs organized by the CIPM (Comité International des Poids et Mesures), show that the uncertainty of the KRISS (Korea Research Institute of Standards and Science) bell prover estimated by this study is reasonable.     

Investigation into calibration performance of small volume prover for hydrocarbon flow

Several kinds of commercial flowmeters, namely, Coriolis flowmeters, turbine meters, ultrasonic flowmeters, and positive displacement flowmeters, have been calibrated using the primary standard for hydrocarbon flow measurement in Japan (which is based on static and gravimetric methods with a flying start and finish) and a small volume prover (SVP) at the same calibration condition in order to investigate the performance of the SVP. The differences in calibration results for the mechanical flowmeters between the primary standard and the SVP apparently depend on the flow rate, although the results show agreement within 0.04%. The computer-based flowmeters, which have a time delay in the output pulse signal, indicated larger differences due to the effect of the sudden flow rate change caused by the proving action of the SVP at larger flow damping times.     

钟罩式气体流量标准装置自动检定系统的研究与设计

针对目前国内生产的钟罩装置多采用人工操作,在检测中需要测得被检表前和标准装置内部的温度、压力以及标定时间、体积流量、累计流量等一系列数据,再进行计算,其工作量大、数据多,且原有装置的同步控制由人工操作来保证,检定过程中存在效率低、操作繁琐等弊端,容易因人为的失误增大检定误差甚至产生错误,并且数据查询困难.因此,笔者研制了由ARM7微处理器为下位机和计算机为上位机的钟罩气体流量标准装置控制自动检定系统,以实现对检定过程的自动控制及数据处理.     

Verification of Software Requirements on Program Systems Represented by Attribute Transition Systems

An approach to the verification of requirements is presented. A formal requirement language is described and the properties to be checked are formulated. A scheme for proving some important dynamic properties is developed.