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Requirements in performance measurement systems of construction projects from the lean production perspective

Karina B. BARTH, Carlos T. FORMOSO

《工程管理前沿（英文）》 2021年第8卷第3期页码 442-455 doi: 10.1007/s42524-020-0108-2

摘要： Performance measurement (PM) generates useful data for process control, facilitates communication between different sectors, and helps to align efforts on the most important aspects of the business. Thus, PM plays a key role in the management of projects and organizations. PM is also important in the implementation of lean production principles and methods, such as reducing the share of nonvalue-adding activities, increasing process transparency, building continuous improvement into the process, and benchmarking. Moreover, the adoption of the lean production philosophy requires changes in PM. Despite its importance, limited studies have been conducted on the use of PM systems for assessing the impact of lean production programs in construction projects. In addition, studies on how lean companies (or projects) use performance measurement and to what extent the indicators adopted reflect the result of actions that have been undertaken are limited. This study proposes a set of requirements in PM systems of construction projects from the perspective of lean production and a taxonomy of performance metrics for lean production systems. Five empirical studies have been carried out on construction companies from South America involved in the implementation of lean production systems. The scope of this investigation is limited to the construction projects as production systems rather than PM at the level of construction organizations.

关键词： performance measurement lean construction production management continuous improvement metrics

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density measurement for plastic injection molding via ultrasonic technology

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0714-2

摘要： Density variation during the injection molding process directly reflects the state of plastic melt and contains valuable information for process monitoring and optimization. Therefore, in-situ density measurement is of great interest and has significant application value. The existing methods, such as pressure−volume−temperature (PVT) method, have the shortages of time-delay and high cost of sensors. This study is the first to propose an in-situ density measurement method using ultrasonic technology. The analyses of the time-domain and frequency-domain signals are combined in the proposed method. The ultrasonic velocity is obtained from the time-domain signals, and the acoustic impedance is computed through a full-spectral analysis of the frequency-domain signals. Experiments with different process conditions are conducted, including different melt temperature, injection speed, material, and mold structure. Results show that the proposed method has good agreement with the PVT method. The proposed method has the advantages of in-situ measurement, non-destructive, high accuracy, low cost, and is of great application value for the injection molding industry.

关键词： ultrasonic measurement melt density in-situ measurement injection molding

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立体偏转测量系统几何参数的性能分析与评价 Article

徐永佳, 高峰, 蒋向前

《工程（英文）》 2018年第4卷第6期页码 806-815 doi: 10.1016/j.eng.2018.10.007

摘要：

本文提出了一种新颖的几何参数分析方法，以提高立体偏转系统的测量精度。立体偏转测量可用于获得自由曲面的三维形貌信息。基于立体偏转测量的测量系统通常由条纹显示屏、主相机和参考相机组成。立体偏转测量系统组件的布置对于实现高精度测量十分重要。本文分析和评估了立体偏转测量系统的4个几何参数：主相机与被测物体表面之间的距离、主相机光线与被测表面法线之间的角度、条纹显示屏与被测物体之间的距离，以及主相机和参考相机之间的角度。本文通过模拟和实验数据对这些几何参数对测量精度的影响进行了验证。实验结果证实了这些参数对测量精度的影响。基于本文所提出的分析方法，一个立体偏转系统被搭建并且被用于测量一个标准的凹面镜。通过与凹面镜的给定表面参数进行比较，该系统的全局测量精度可达154.2 nm。

关键词：光学测量误差分析立体偏转测量三维形貌测量性能评估模拟

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基于亚马逊热带雨林的HY-2卫星微波散射计在轨测量性能分析

彭海龙,穆博,林明森,周武

《中国工程科学》 2014年第16卷第6期页码 33-38

摘要：

中国第一颗自主海洋动力环境卫星海洋二号（HY-2）卫星于2011 年8 月16 日成功发射，其上搭载的Ku波段微波散射计可以提供海面风矢量信息。根据国际上对已发射星载微波散射计在亚马逊热带雨林的研究结果：散射计在该地理区域观测的后向散射系数随季节的变化在0.15 dB以内。本文对HY-2 微波散射计2012—2013 年的亚马逊热带雨林区域的观测数据进行了分析，结果表明HY-2 卫星散射计在轨运行两年来的测量性能很稳定，其在亚马逊热带雨林的季节性变化特征与国际上的研究结果一致。

关键词：亚马逊热带雨林 HY-2 微波散射计在轨测量性能

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A measurement system for thin elastohydrodynamic lubrication films

WANG Xuefeng, GUO Feng, YANG Peiran

《机械工程前沿（英文）》 2007年第2卷第2期页码 193-196 doi: 10.1007/s11465-007-0032-8

摘要： An elastohydrodynamic lubrication (EHL) film measurement system using multi-beam interferometry is introduced in this paper. The measurement principle and the instrumentation are discussed. A simple and efficient method is suggested to obtain the fringe order of measured points. It is demonstrated that the presented measurement system can provide continuous measurement of lubricating films from nano to micro scales at a nano-level resolution, and can be used to investigate ultra-thin EHL films and tiny variations in EHL films.

关键词： instrumentation continuous measurement elastohydrodynamic lubrication ultra-thin measurement

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Implementation and performance evaluation of advance metering infrastructure for Borneo-Wide Power Grid

Mujahid TABASSUM,Manas K. HALDAR,Duaa Fatima S. KHAN

《能源前沿（英文）》 2020年第14卷第1期页码 192-211 doi: 10.1007/s11708-016-0438-2

摘要： In this paper, a supervisory computer network for Borneo-Wide Power Grid system have been proposed and implemented, which includes a renewable power generation and advanced metering infrastructure. An Internet-based communication network running on multiprotocol label switching (MPLS) has been implemented for a smart power grid, with the addition of the renewable energy monitoring system. The centralized supervisory control and data acquisition systems (SCADA) are replaced by a wide area monitoring system(WAMS) comprising of a phasor measurement unit (PMU). The implemented communication network used advanced metering infrastructure that operates on worldwide interoperability for microwave access (WiMAX), wireless fidelity (Wi-Fi) and low power Wi-Fi, which are proposed for the distribution systems of Sarawak Energy. The proposed wide area network (WAN) is simulated using OPNET Modeler and the results are compared with the existing WAN used by Sarawak Energy.

关键词： renewable energy multiprotocol label switching (MPLS) power grid phasor measurement unit (PMU) supervisory control and data acquisition systems (SCADA) wide area monitoring system (WAMS) worldwide interoperability for microwave access (WiMAX) synchronous digital hierarchy (SDH)

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Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

《结构与土木工程前沿（英文）》 2007年第1卷第4期页码 448-457 doi: 10.1007/s11709-007-0061-8

摘要： The double- fracture model can well describe the development of cracks undergoing during the entire fracture process in concrete. Therefore, it has been selected as the theoretical basis of the Norm for fracture test of

关键词： development concrete theoretical double- fracture

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Study on direct measurement method of vorticity from particle images

RUAN Xiaodong, FU Xin, YANG Huayong

《能源前沿（英文）》 2007年第1卷第4期页码 408-412 doi: 10.1007/s11708-007-0059-1

摘要： To overcome the shortcomings of conventional methods for vorticity measurement, a new direct measurement of vorticity (DMV) method extracting vorticity from particle images was proposed. Based on the theory of fluid flow, two matc

关键词： conventional vorticity measurement particle DMV theory

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Ultrasonic measurement of tie-bar stress for die-casting machine

《机械工程前沿（英文）》 doi: 10.1007/s11465-021-0663-1

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针对目标跟踪的两种基于最大期望算法测量值偏差估计过程的性能分析 None

Zhi-hua LU, Meng-yao ZHU, Qing-wei YE, Yu ZHOU

《信息与电子工程前沿（英文）》 2018年第19卷第9期页码 1151-1165 doi: 10.1631/FITEE.1800214

摘要：在现实目标跟踪问题中，传感器采集的测量值，比如系统缺陷，可能存在一定程度偏差。为正确估计目标的运动轨迹，测量值偏差的识别与估计将成为首要任务。首先，提出两种状态空间模型，分别把测量值偏差视为随机变量和常数。其次，假设测量值样本数足够大，基于最大期望算法，利用扩展卡尔曼滤波和平滑，针对两种模型提出不同的循环迭代偏差估计过程。最后，分析这两种估计过程的全局收敛结果，揭示其内在联系。结果表明，第二种估计过程比第一种估计过程更简单准确，并且收敛速度更快。批量处理测量值样本后，可同时获得目标运动轨迹和测量值偏差的估计结果。

关键词：非线性状态空间模型；测量值偏差；扩展卡尔曼滤波；扩展卡尔曼平滑；最大期望算法

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齿轮测量技术100年——回顾与展望

石照耀,费业泰,谢华锟

《中国工程科学》 2003年第5卷第9期页码 13-17

摘要：

全面概述了过去100年齿轮测量技术的发展历程，给出了6件标志性事情；着重论述了测量原理的演变、实现测量原理技术方式的发展以及测量结果的表述与利用；介绍了当今CNC齿轮测量中心的原理、组成和特点；结合90年代以来齿轮测量技术领域中几股新潮流，展望了未来齿轮测量技术的一些研究方向。

关键词：齿轮齿轮测量齿轮误差齿轮测量仪器

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脉冲中子、伽马探测系统性能表征与设计技术

欧阳晓平

《中国工程科学》 2009年第11卷第5期页码 44-53

摘要：

探测系统是获取辐射场特征信息的核心器件，是实施脉冲辐射探测的关键和技术基础，其性能直接决定测试数据的质量和测试方法的选择。对影响脉冲辐射探测的性能指标进行系统描述、表征是探测系统设计、研制、实际应用和综合性能评价的基础。用于复杂能谱脉冲中子、伽马混合辐射场时间谱、强度谱测量的探测系统，主要性能包括探测灵敏度、时间响应、能量响应、线性电流和中子、伽马分辨能力等指标参数，这些参数的获得与实现，需要根据中子、伽马射线与物质相互作用的基本原理，构建相应的探测结构和技术原理。在设计上，综合权衡能量收集和电荷收集方式选择、几何效率完备和高信噪比结合、信号响应和直照响应分离、探测效率与时间特性兼顾、综合性能与使用可靠性一致等设计原则，综合应用这些原则构成了探测系统设计方法。

关键词：中子、伽马混合场脉冲辐射探测探测系统设计原理性能参数

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Single-electromagnet levitation for density measurement and defect detection

Yuhan JIA, Peng ZHAO, Jun XIE, Xuechun ZHANG, Hongwei ZHOU, Jianzhong FU

《机械工程前沿（英文）》 2021年第16卷第1期页码 186-195 doi: 10.1007/s11465-020-0608-0

摘要： This paper presents a single-electromagnet levitation device to measure the densities and detect the internal defects of antimagnetic materials. The experimental device has an electromagnet in its lower part and a pure iron core in the upper part. When the electromagnet is activated, samples can be levitated stably in a paramagnetic solution. Compared with traditional magnetic levitation devices, the single-electromagnet levitation device is adjustable. Different currents, electromagnet shapes, and distances between the electromagnet and iron core are used in the experiment depending on the type of samples. The magnetic field formed by the electromagnet is strong. When the concentration of the MnCl aqueous solution is 3 mol/L, the measuring range of the single-electromagnet levitation device ranges from 1.301 to 2.308 g/cm . However, with the same concentration of MnCl aqueous solution (3 mol/L), the measuring range of a magnetic levitation device built with permanent magnets is only from 1.15 to 1.50 g/cm . The single-electromagnet levitation device has a large measuring range and can realize accurate density measurement and defect detection of high-density materials, such as glass and aluminum alloy.

关键词： single-electromagnet electromagnetic levitation density measurement defect detection

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Measurement and analysis of tip clearance unsteady flow spectrum in axial-flow fan rotor

LIU Bo, HOU Weimin, MA Changyou, WANG Yangang, ZHOU Qiang

《能源前沿（英文）》 2008年第2卷第4期页码 448-452 doi: 10.1007/s11708-008-0088-0

摘要： The dynamic pressure measurement device and test technology are described in this study. The tip clearance unsteady flow development from the inlet to the outlet of an axial-flow rotor was revealed by analyzing pressure frequency spectrum acquired from measuring the unsteady pressure field of the tip endwall. The experiment provides test basis for thoroughly understanding the tip clearance unsteady flow and building interaction models of tip clearance flow and main flow.

关键词： development endwall unsteady pressure pressure measurement experiment