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EDCMS:A Content Management System for Engineering Documents

International Journal of Automation and computing 2007年第1期4卷 56-70页

作者： Chris McMahon Mansur Darlington steve Culley Peter Wild Department of Mechanical Engineering University of BathClaverton DownBath BA2 7AYUK

Engineers often need to look for the right pieces of information by sifting through long engineering documents, It is a very tiring and time-consuming job. To address this issue, researchers are increasingly devoting their attention to new ways to help information users, including engineers, to access and retrieve document content. The research reported in this paper explores how to use the key technologies of document decomposition （study of document structure）, document mark-up （with EXtensible Mark- up Language （XML）, HyperText Mark-up Language （HTML）, and Scalable Vector Graphics （SVG））, and a facetted classification mechanism. Document content extraction is implemented via computer programming （with Java）. An Engineering Document Content Management System （EDCMS） developed in this research demonstrates that as information providers we can make document content in a more accessible manner for information users including engineers.The main features of the EDCMS system are： 1） EDCMS is a system that enables users, especially engineers, to access and retrieve information at content rather than document level. In other words, it provides the right pieces of information that answer specific questions so that engineers don＇t need to waste time sifting through the whole document to obtain the required piece of information. 2） Users can use the EDCMS via both the data and metadata of a document to access engineering document content. 3） Users can use the EDCMS to access and retrieve content objects, i.e. text, images and graphics （including engineering drawings） via multiple views and at different granularities based on decomposition schemes. Experiments with the EDCMS have been conducted on semi-structured documents, a textbook of CADCAM, and a set of project posters in the Engineering Design domain. Experimental results show that the system provides information users with a powerful solution to access document content.

关键词： Document content management engineering design decomposition schemes document mark-up facetted classification.

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铝合金激光双光点焊接工艺特性

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焊接学报 2007年第4期28卷 108-112页

作者：姚伟巩水利 steve Shi 北京航空制造工程研究所高能束流加工技术国防科技重点实验室北京100024 英国焊接研究所

对铝合金薄板激光单光点和双光点焊接(包括不填丝和填丝)的焊缝成形、对接间隙和准直度容许裕度以及气孔状况进行了比较,并分析了双光点能量分布的激光对铝合金焊接的影响。结果表明,与激光单光点焊接相比,激光双光点焊接铝合金所得焊... 详细信息

对铝合金薄板激光单光点和双光点焊接(包括不填丝和填丝)的焊缝成形、对接间隙和准直度容许裕度以及气孔状况进行了比较,并分析了双光点能量分布的激光对铝合金焊接的影响。结果表明,与激光单光点焊接相比,激光双光点焊接铝合金所得焊缝表面质量更好,焊缝熔宽更大,对接间隙和准直度容许裕度明显放宽。激光双光点焊接铝合金可以显著减少焊缝中大气孔的数量,但对焊缝中小气孔数量的影响不明显。此外,填加焊丝可以进一步改善焊缝表面质量并放宽对接间隙和准直度容许裕度,但将增大焊缝产生大气孔的倾向,采用激光双光点焊接仍可使焊缝中大气孔的数量明显减少。

关键词：激光焊接单光点双光点填加焊丝铝合金

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基于像元和对象分类的城区植被高分辨率遥感制图比较研究

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应用基础与工程科学学报 2011年第3期19卷 441-448页

作者：谭衢霖 steve Johansen 北京交通大学土木建筑工程学院北京100044 西安大略大学地理系加拿大安大略

本研究利用高空间分辨率遥感影像和LiDAR数据,参照美国USGS植被分类体系,在两种不同分类层次上,评价了基于像元和基于对象分类两种方法的城区植被覆盖专题制图效果.采用传统的基于像元监督最大似然分类时,在下层分类层次,分类总精度仅为... 详细信息

本研究利用高空间分辨率遥感影像和LiDAR数据,参照美国USGS植被分类体系,在两种不同分类层次上,评价了基于像元和基于对象分类两种方法的城区植被覆盖专题制图效果.采用传统的基于像元监督最大似然分类时,在下层分类层次,分类总精度仅为70.5%,Kappa系数为63.5%.当在上层分类层次进行分类时,分类精度相对下层分类层次有明显提高,总精度达84%,Kappa系数为75.8%.而采用面向对象的分类方法时,在下层分类层次,分类总精度为86%,Kappa系数为82.3%.在上层分类层次,总精度达90.8%,Kappa系数为86.2%.研究结果表明,在城区两种不同植被分类层次,面向对象分类结果都取得了优于基于像元的分类结果.

关键词：高分辨率影像城区植被分类制图

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Two methods for separating the magnetospheric solar wind charge exchange soft X-ray emission from the diffuse X-ray background

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Earth and Planetary Physics 2024年第1期8卷 119-132页

作者： YingJie Zhang TianRan Sun JenniferACarter WenHao Liu steve Sembay ShuiNai Zhang Li Ji Chi Wang State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China College of Earth and Planetary Sciences The University of Chinese Academy of SciencesBeijing 100190China School of Physics and Astronomy The University of LeicesterLeicesterUK Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China

Solar wind charge exchange(SWCX)is the process of solar wind high-valence ions exchanging charges with neutral components and generating soft ***,detecting the SWCX emission from the magnetosphere is proposed as a new technique to study the magnetosphere using panoramic soft X-ray *** better prepare for the data analysis of upcoming magnetospheric soft X-ray imaging missions,this paper compares the magnetospheric SWCX emission obtained by two methods in an XMM-Newton observation,during which the solar wind changed *** two methods differ in the data used to fit the diffuse X-ray background(DXB)parameters in spectral *** method adding data from the ROSAT All-Sky Survey(RASS)is called the RASS *** method using the quiet observation data is called the Quiet method,where quiet observations usually refer to observations made by the same satellite with the same target but under weaker solar wind *** show that the spectral compositions of magnetospheric SWCX emission obtained by the two methods are very similar,and the changes in intensity over time are highly consistent,although the intensity obtained by the RASS method is about 2.68±0.56 keV cm^(-2)s^(-1)sr^(-1)higher than that obtained by the Quiet *** the DXB intensity obtained by the RASS method is about 2.84±0.74 keV cm^(-2)s^(-1)sr^(-1)lower than that obtained by the Quiet method,and the linear correlation coefficient between the difference of SWCX and DXB obtained by the two methods in diffe rent energy band is close to-1,the diffe rences in magnetospheric SWCX can be fully attributed to the diffe rences in the fitted *** difference between the two methods is most significant when the energy is less than 0.7 keV,which is also the main energy band of SWCX *** addition,the difference between the two methods is not related to the SWCX intensity and,to some extent,to solar wind conditions,because SWCX intensity typically va ries with the

关键词： solar wind charge exchange(SWCX) ROSAT All-Sky Survey(RASS) soft X-ray X-ray imaging magnetosphere

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Productivity Gap and Inward FDI Spillovers: Theory and Evidence from China

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China & World Economy 2021年第2期29卷 24-48页

作者： Jim Huangnan Shen Hao Wang steve Chu-Chia Lin School of Management Fudan UniversityChina Center for International Development Harvard Kennedy SchoolUS School of Economics and Trade Guangdong University of Foreign StudiesChina School of Slavonic and East European Studies University College LondonUK Department of Economics National Chengchi UniversityTaiwanChina

This paper constructs a two-stage sequential game model to shed light on the spillover effect of inward FDI on the efficiency of domestic firms in host *** model shows that,given an optimal joint-venture policy made by foreign firms,the impact of the spillover effect of inward FDI is contingent upon the productivity gap between the domestic firms and foreign *** particular,we demonstrate that the spillover effect of inward FDI varies negatively with the productivity gap between domestic lowproductivity firms and foreign firms but works in the opposite way for high-productivity *** suggests that once the productivity gap widens,the entry of foreign firms will increase the efficiency of high-productivity firms but reduce the efficiency of lowproductivity *** support of our theoretical model,we provide robust empirical results by using the dataset of annual survey of Chinese industrial enterprises.

关键词： efficiency improvement inward FDI productivity gap spillover effect

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A comparison of fish tissue mercury concentrations from homogenized fillet and nonlethal biopsy plugs

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Journal of Environmental Sciences 2019年第6期31卷 137-145页

作者： Alexis Knight Satyendra P.Bhavsar Brian A.Branfireun Peter Drouin Ram Prashad steve Petro Moustapha Oke Department of Biology and Centre for Environment and Sustainability Western University Ontario Ministry of the Environment Conservation and Parks

The use of biopsy plugs to sample fish muscle tissue for mercury analyses is a viable alternative to lethal sampling; however, the practice has yet to be widely implemented in routine monitoring due to concerns about variability of mercury concentrations in fish muscle tissues. Here we examine distribution of mercury in fillets of four fish species(Walleye, Northern Pike, Smallmouth Bass and Lake Trout), suitability of left/right side of fillet for biopsy sampling, and appropriateness of re-using a biopsy punch. The results showed that average mercury concentrations in left and right fillets of fish are *** concentrations in biopsy plug samples, taken from the anterior dorsal area of the fish fillet, were statistically equivalent to the mercury concentrations in homogenized fillets. There was no discernible cross contamination between samples when a biopsy punch was reused after washing in hot soapy water, and as such, biopsy punches can be recycled during sampling to reduce the sampling cost. If a tissue mass collected from a specific site on the fillet is insufficient, then we suggest sampling corresponding locations on the other fillet rather than sampling two adjacent sites on one fillet to obtain more tissue. The results presented here can improve the accuracy of fillet biopsy plug sampling,minimize fish mortality for mercury monitoring, and reduce labor and material costs in monitoring programs.

关键词： Hg or mercury Fish advisory Nonlethal Monitoring Muscle tissue Biopsy punch plug

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Interspecific competition predicts the potential impact of little fire ant Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae) invasion on resident ants in southern China

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Insect Science 2023年第5期30卷 1518-1532页

作者： Lei Nie Bamisope steve Bamisile Yuling Li Hao Ran Suhang Wang Lei Wang Yijuan Xu Red Imported Fire Ant Research Center South China Agricultural UniversityGuangzhouChina

The little fire ant Wasmannia auropunctata(Roger)is a major invasive species that seriously threatens the biodiversity of invaded *** was first reported in Chinese mainland in 2022 and its impact on native species is still *** evaluate the impact of *** invasion on the ant communities in southern China,a series of interspecific competition experiments were conducted in this *** individual aggression index and group aggression experiments showed the advantage of *** in competition with 5 resident ants under equal worker *** encountering Anoplolepis gracilipes,Camponotus nicobarensis,Tetramorium bicarinatum,Polyrhachis dives,and Solenopsis invicta,*** gradually gained a competitive advantage with an increase in its number of *** the group aggression experiments with equal worker numbers,there was a negative correlation between the body length and mortality rate of resident *** results of the foraging behavior experiments showed that *** was able to dominate food resources under competition with Carebara diversa,which also displayed weak competition in the group aggression *** addition,the abilities to recruit workers and retrieve food were inhibited under competition with *** and *** results of the nesting behavior experiments showed that in the 24-h bout of space resource competition,*** was dominant over ***,***,and *** results of this study show that *** has certain advantages in competition for food and space resources over resident ants in southern China,and some resident ant species may be replaced in the future.

关键词： aggression foraging competition interspecific competition nesting compe-tition W.auropunctata

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Genetic Interactions Reveal that Speci c Defects of Chloroplast Translation are Associated with the Suppression of var2-Mediated Leaf Variegation

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Journal of Integrative Plant Biology 2013年第10期55卷 979-993页

作者： Xiayan Liu Mengdi Zheng Rui Wang Ruijuan Wang Lijun An steve R.Rodermel Fei Yu State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences Northwest A&F University Department of Genetics Development and Cell Biology Iowa State University

Arabidopsis thaliana L. yellow variegated （var2） mutant is defective in a chloroplast FtsH family metalloprotease, AtFtsH2/VAR2, and displays an intriguing green and white leaf variegation. This unique var2-mediated leaf variegation offers a simple yet powerful tool for dissecting the genetic regulation of chloroplast development. Here, we report the isolation and characterization of a new var2 suppressor gene, SUPPRESSOR OF VARIEGA TION8 （SVR8）, which encodes a putative chloroplast ribosomal large subunit protein, L24. Mutations in SVR8 suppress var2 leaf variegation at ambient temperature and partially suppress the cold-induced chlorosis phenotype of var2. Loss of SVR8 causes unique chloroplast rRNA processing defects, particularly the 23S-4.5S dicistronic precursor. The recovery of the major abnormal processing site in svr823S-4.5S precursor indicate that it does not lie in the same position where SVR8/L24 binds on the ribosome. Surprisingly, we found that the loss of a chloroplast ribosomal small subunit protein, $21, results in aberrant chloroplast rRNA processing but not suppression of var2 variegation. These findings suggest that the disruption of specific aspects of chloroplast translation, rather than a general impairment in chloroplast translation, suppress var2variegation and the existence of complex genetic interactions in chloroplast development.

关键词： Chloroplast ribosomal protein L24 chloroplast rRNA processing genetic suppressor leaf variegation var2.

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New Opportunities for Lanthanide Luminescence

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Journal of Rare Earths 2007年第3期25卷 257-274页

作者： Jean-Claude G. Bünzli steve Comby Anne-Sophie Chauvin Caroline D. B. Vandevyver Laboratory of Lanthanide Supramolecular Chemistry Ecole Polytechnique Fédérale de Lausanne BCH 1402 CH-1015 Lausanne Switzerland

Trivalent lanthanide ions display fascinating optical properties. The discovery of the corresponding elements and their first industrial uses were intimately linked to their optical properties. This relationship has been kept alive until today when many high-technology applications of lanthanide-containing materials such as energy-saving lighting devices, displays, optical fibers and amplifiers, lasers, responsive luminescent stains for biomedical analyses and in cellulo sensing and imaging, heavily rely on the brilliant and pure-color emission of lanthanide ions. In this review we first outlined the basics of lanthanide luminescence with emphasis on f-f transitions, the sensitization mechanisms, and the assessment of the luminescence efficiency of lanthanide-containing emissive molecular edifices. Emphasis was then put on two fast developing aspects of lanthanide luminescence： materials for telecommunications and light emitting diodes, and biomedical imaging and sensing. Recent advances in NIR-emitting materials for plastic amplifiers and waveguides were described, together with the main solutions brought by researchers to minimize non-radiative deactivation of excited states. The demonstration in 1999 that erbium tris（8-hydroxyquinolinate） displayed a bright green emission suitable for organic light emitting diodes （OLEDs） was followed by realizing that in OLEDs, 25% of the excitation energy leads to singlet states and 75% to triplet states. Since lanthanide ions are good triplet quenchers, they now also play a key role in the development of these lighting devices. Luminescence analyses of biological molecules are among the most sensitive analytical techniques known. The long lifetime of the lanthanide excited states allows time-resolved spectroscopy to be used, suppressing the sample autofluorescence and reaching very low detection limits. Not only visible lanthanide sensors are now ubiquitously provided in medical diagnosis and in cell imaging, but the feasibili

关键词： lanthanide luminescence sensitization near infrared telecommunications organic light emitting diode (OLED) time-resolved luminescence in cellulo sensing cell imaging rare earths

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辉光放电质谱法测定超高纯铜中痕量杂质的记忆效应研究

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冶金分析 2011年第9期31卷 22-23页

作者： GUILFOYLE steve Nu仪器公司

随着高纯材料的需求日益增大,分析这种材料的辉光放电质谱技术也在不断的完善,其中一个困扰业界的问题就是记忆效应。本文采用辉光放电质谱法在分析锌样品前后分别两次测定了超高纯铜样品中10种痕量杂质(Mg、Al、Cr、Mn、Fe、Ni、Zn、As... 详细信息

随着高纯材料的需求日益增大,分析这种材料的辉光放电质谱技术也在不断的完善,其中一个困扰业界的问题就是记忆效应。本文采用辉光放电质谱法在分析锌样品前后分别两次测定了超高纯铜样品中10种痕量杂质(Mg、Al、Cr、Mn、Fe、Ni、Zn、As、Hg、Pb)。结果表明,两次测定结果基本一致,尤其是两次测定所得痕量锌含量结果一致,说明改变样品基体时,采用只清洗辉光放电池的方法可消除记忆效应。

关键词：超高纯铜辉光放电质谱法记忆效应

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