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On-line Tool Wear Classification in Unmanned-machining Environments

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厦门大学学报（自然科学版） 2002年第S1期41卷 80-81页

作者： A D Hope g A king Systems Engineering Faculty Southampton InstituteSystems Engineering Faculty Southampton Institute Southampton UKSouthampton UK

One of the most important features of the modern ma ch ining system in an "unmanned" factory is to change tools that have been subjec ted to wear and damage. An integrated tool condition monitoring system composed of multi-sensors, signal processing devices and intelligent decision making pla ns is a necessary requirement for automatic manufacturing processes. An intellig ent tool wear monitoring system will be introduced in this paper. The system is equipped with power consumption, vibration, AE and cutting force sensors, signal transformation and collection apparatus and a microcomputer. Tool condition monitoring is a pattern recognition process in which the characte ristics of the tool to be monitored are compared with those of the standard mode ls. The tool wear classification process is composed of the following parts: fea ture extraction; determination of the fuzzy membership functions of the features ; calculation of the fuzzy similarity; learning and tool wear classification. Fe atures extracted from the time domain and frequency domain for the future patter n recognition are as follows. Power consumption signal: mean value; AE-RMS sign al: mean value, skew and kutorsis; Cutting force, AE and vibration signal: mean value, standard deviation and the mean power in 10 frequency ranges. These signa l features can reflect the tool wear states comprehensively. The fuzzy approachi ng degree and the fuzzy distance between corresponding features of different obj ects are combined to describe the closeness of two fuzzy sets more accurately. A unique fuzzy driven neural network based pattern recognition algorithm has bee n developed from this research. The combination of Artificial Neural Networks (A NNs) and fuzzy logic system integrates the strong learning and classification ab ility of the former and the superb flexibility of the latter to express the dist ribution characteristics of signal features with vague boundaries. This methodol ogy indirectly solves the auto

关键词： condition monitoring feature extraction fuzzy logic and neural networks sensor fusion pattern recognition

Effect of Surfactants on the Thermoelectric Performance of Double-Walled Carbon Nanotubes

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Energy & Environmental Materials 2023年第1期6卷 274-280页

作者： Zakaria Saadi Simon g.king Jose V.Anguita Vlad Stolojan S.Ravi P.Silva Department of Electrical and Electronic Engineering Advanced Technology InstituteUniversity of SurreyGuildford GU27XHUK

Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as ***,their conversion efficiency is low and the best performing materials are brittle,toxic,and made of expensive *** challenge in developing better performing materials is in disrupting the electrical vs thermal conductivity correlation,to achieve low thermal conductivity simultaneously with a high electrical *** nanotubes allow for the decoupling of the electronic density of states from the phonon density of states and this paper shows that flexible,thin films of double-walled carbon nanotube(DWCNT)can form effective n-and p-doped semiconductors that can achieve a combined Seebeck coefficient of 157.6µV K^(−1),the highest reported for a single DWCNT device to *** is achieved through selected surfactant doping,whose role is correlated with the length of the hydrocarbon chain of the hydrophobic tail group of the surfactant’s *** functionalized with Triton X-405 show the highest output power consisting of a single junction of p-and n-type thermoelectric elements,reaching as high as 67 nW for a 45 K temperature *** enabling flexible,cheaper,and more efficient thermoelectric generators through the use of functionalized CNTs.

关键词： carbon nanotubes DWCNT functionalization surfactant thermoelectric

A two-phase study evaluating the relationship between Thimerosal-containing vaccine administration and the risk for an autism spectrum disorder diagnosis in the United States

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Translational Neurodegeneration 2013年第1期2卷 183-194页

作者： David A geier Brian S Hooker Janet K Kern Paul g king Lisa K Sykes Mark R geier The Institute of Chronic Illnesses Inc 14 Redgate CtSilver SpringMDUSA Simpson University ReddingCAUSA University of Texas Southwestern Medical Center at Dallas DallasTXUSA CoMeD Inc Silver SpringMDUSA

Background:Autism spectrum disorder(ASD)is defined by standardized criteria of qualitative impairments in social interaction,qualitative impairments in communication,and restricted and stereotyped patterns of behavior,interests,and activities.A significant number of children diagnosed with ASD suffer a loss of previously-acquired skills,which is suggestive of neurodegeneration or a type of progressive encephalopathy with an etiological pathogenic basis occurring after *** date,the etiology of ASD remains under debate,however,many studies suggest toxicity,especially from mercury(Hg),in individuals diagnosed with an *** present study evaluated concerns about the toxic effects of organic-Hg exposure from Thimerosal(49.55%Hg by weight)in childhood vaccines by conducting a two-phased(hypothesis generating/hypothesis testing)study with documented exposure to varying levels of Thimerosal from ***:A hypothesis generating cohort study was undertaken to evaluate the relationship between exposure to organic-Hg from a Thimerosal-containing Diphtheria-Tetanus-acellular-Pertussis(DTaP)vaccine in comparison to a Thimerosal-free DTaP vaccine administered,from 1998 through 2000,for the risk of ASD as reported in the Vaccine Adverse Event Reporting System(VAERS)database(phase I).A hypothesis testing case–control study was undertaken to evaluate the relationship between organic-Hg exposure from Thimerosal-containing hepatitis B vaccines administered at specific intervals in the first six months of life among cases diagnosed with an ASD and controls born between 1991 through 1999 in the Vaccine Safety Datalink(VSD)database(phase II).Results:In phase I,it was observed that there was a significantly increased risk ratio for the incidence of ASD reported following the Thimerosal-containing DTaP vaccine in comparison to the Thimerosal-free DTaP *** phase II,it was observed that cases diagnosed with an ASD were significantly more likely than controls to rece

关键词： Autism Ethylmercury Merthiolate Thimerosal Thiomersal Vaccine

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英国煤炭公司的条一条3.3KV采煤工作面

矿业译文 1995年第1期 1-6页

作者： king,g 卢共平

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4—D地震技术改善了油藏管理决策（一）

石油勘探开发情报 1996年第3期 25-28页

作者： king,g 吴官生

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4—D地球技术改善了油藏管理决策（二）

石油勘探开发情报 1996年第4期 15-21页

作者： king..,g 吴官生

geophysical and Hydrogeological groundwater Prospectivity Mapping in the Kraaipan granite-greenstone Terrain, Southeast Botswana

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Journal of Water Resource and Protection 2017年第11期9卷 1270-1298页

作者： Rubeni T. Ranganai Moikwathai D. Moidaki James g. king Zibisani B. Bagai Department of Physics University of Botswana Gaborone Botswana Department of geology University of Botswana Gaborone Botswana

Application of regional geophysical methods for hydrogeological purposes has increased over the last two decades especially in arid and semi-arid areas. A project to map the Kraaipan granite-greenstone terrain in southeast Botswana has recently been undertaken using regional aeromagnetic and gravity data with the aim to map the rocks at depth to understand the geology while the secondary objective was to subsequently assess the mineralization and groundwater potential in the area. An integrated analysis of the aeromagnetic and gravity data and their derived/processed products is hereby investigated for groundwater for drinking and agricultural purposes. The studies include: subsurface characterisation and delineation of structural framework suitable for groundwater exploration and determination of petrophysical relationships used to link the geophysical properties (e.g., density) to hydrological properties (e.g., porosity). The results of interpretation indicate that the rocks are under ~50 m of Kalahari cover and the study area is composed of three aquifers: the extensive hard rock aquifer (granitic and volcanic), the important (fractured) karst aquifer and the minor sedimentary aquifer. The area is dissected by an ENE-to-EW-trending dyke swarm visible on the regional aeromagnetic data and much clearer on high resolution aeromagnetic data. Minor fault and/or dyke elements of NW-SE and NE-SW trend are observed. Spectral analysis reveals three main average ensample interfaces at depths of 0.7 km, 1.99 km and 4.8 km. The linear Euler solutions maps reveal that the majority depths to top of magnetic bodies range from 40 m to 400 m throughout the survey area. The shallowest depths are the most significant one in this case as they probably relate to depth of bedrock and thickness of regolith or thickest sediments. For 2695 existing boreholes analysed, maximum borehole depth is 482 m (mean 108 m), and almost half (1263) were dry with another 972 having low yield (1 - 5 m3

关键词： Aeromagnetic Data gravity Data Crystalline Basement Karst Aquifer groundwater Prospectivity Borehole Yield Southeast Botswana

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4-D地震提高油藏管理决策

石油物探译丛 1996年第6期 22-23页

作者： g. king 杨斌

如今,地震技术日益发展,我们可以获得油藏中流体区域分布以及与深度有关的可靠信息。这种信息可以帮助我们更好地作出决策,模拟各种不同的方案来优化石油开采,提高采收率,降低成本。这些发展的整体就是4-D或称为时间推移3-D地震勘探。... 详细信息

如今,地震技术日益发展,我们可以获得油藏中流体区域分布以及与深度有关的可靠信息。这种信息可以帮助我们更好地作出决策,模拟各种不同的方案来优化石油开采,提高采收率,降低成本。这些发展的整体就是4-D或称为时间推移3-D地震勘探。在过去的十年中,许多对各种地质条件和储层条件保密的成功的地震油藏监测技术的实例研究已经公开。本文研究4-D技术的主要问题,同时考虑到正在进行的成功的4-D工程所需要的不同阶段。

关键词： 4-D地震油气采收率储层特征油藏

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大陆走滑地震断层参数的标定

世界地震译丛 2008年第4期39卷 13-21页

作者： g.C.P.king S.g.Wesnousky 吴江星吉林省地震局长春三岗地震台

通过应用简单的位移-深度函数,并假定"孕震区的基底并非发生了粘性张弛而产生,而是在介质(该介质在破裂处或邻近破裂处仍保持应力状态)中转变为稳定滑动的结果",我们解决了弹性位错模型预报地震与平均同震滑动随着破裂长度的增加而增加... 详细信息

通过应用简单的位移-深度函数,并假定"孕震区的基底并非发生了粘性张弛而产生,而是在介质(该介质在破裂处或邻近破裂处仍保持应力状态)中转变为稳定滑动的结果",我们解决了弹性位错模型预报地震与平均同震滑动随着破裂长度的增加而增加的观测情况之间长期存在的矛盾。最终结果模型含有在地震尺度的整个波谱上地震具有自相似性的概念。

关键词：地震孕震区滑动分布破裂长度震源参数应力降应变阶跃位移场断层长度走滑大陆地貌