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341.
《Journal of Manufacturing Processes》2014,16(1):109-122
This paper presents some new evolutions of research works in the IRWTL at SJTU on intelligentized technologies for arc welding dynamic process and robot systems, including multi-information sensing of arc welding process, such as characteristic extraction of weld pool image, voltage, current, and sound, arc-spectral features; multi-information fusion algorithms for prediction of weld penetration; intelligentized modeling of welding dynamic process; intelligent control methodology for welding dynamic process; intelligentized technologies for robotic welding, such as guiding and tracking seam technology and intelligent control of weld pool and penetration in robotic welding process; and development of autonomous welding robot system for the special environment. The ideas of intelligentized welding manufacturing technology (IWMT) and intelligentized welding manufacturing engineering (IWME) are presented in this paper for systematization of intending researches and applications on intelligentized technologies for modern welding manufacturing. The studies of intelligentized welding presented in this paper establish the foundation work of intending researches and applications on intelligentized technologies for modern welding manufacturing. 相似文献
342.
根据中国石化企业实际运行情况,介绍了整合QHSE管理体系时的过程和方法,指出了QHSE管理体系一体化整合过程中存在的问题,以及QHSE体系整合对企业的效果。 相似文献
343.
根据中国在处置石化企业及园区突发环境事件的现状,明确了消防部门在现场处置中的先锋、基础和保证的重要作用。经过分析石化行业所存在的火灾、爆炸和环境的风险,提出了在抢险救灾中的选择环保泡沫、采取控而不灭措施、妥善处理泄漏物和消防污水等要求。指出当前环保和消防部门应建立预案、信息、技术、出警等方面应急联动的机制,并在现场处置中强化防护与协同、调查与询情、监测与侦检、警戒与警示、救生与救护、控险与输转、关阀与堵漏、洗消与清理等具体联动措施。 相似文献
344.
In financial time series, persistence or inertia is a feature usually observable in absolute returns, i.e., a proxy for volatility. Moreover, asset return series should be essentially unpredictable according to the efficiency market hypothesis (EMH) in its weak form. Surprisingly, recent literature has found evidence of anti-persistence in technology stocks and commodity futures returns. Anti-persistence would be indicative of an overreaction of asset prices to incoming information. 相似文献
345.
In Europe, sustainable development (SD) is pursued with not one but two overarching strategies, i.e., the so-called Lisbon and SD strategies. While the Lisbon Strategy is a genuinely European response to global economic and social pressures, SD strategies are national efforts corresponding with international (mainly United Nations) guidance to better coordinate and integrate economic, social and, in particular, environmental policies. The present paper explores the vertical coordination and coherence of the two pan-European strategies. After reviewing the international background of SD strategies and the EU origins of the Lisbon strategy, the paper characterizes and compares the governance architectures of the two strategies. With a solid background on how vertical policy integration functions in the two processes, the paper then shows how this affects the coherence of respective strategy structures and monitoring indicators. Based on an extensive empirical stocktaking study of the objectives and indicators in Lisbon and SD strategies across Europe it is shown that, despite the stronger European coordination through the Open Method of Coordination, the Lisbon process entailed only slightly more coherent national strategies than international guidance did in the context of SD strategies. Thus, the paper concludes that the influence international organizations such as the UN and the OECD have on national policy-making must not be underestimated. 相似文献
346.
采用三维激发发射矩阵荧光光谱、平行因子分析(EEM-PARAFAC)和荧光区域积分方法(FRI),研究川西高原3200~4000m高寒土壤DOM特征及其在海拔梯度上变化规律.结果表明,高寒土壤DOC含量为0.47~0.81g/kg,随着海拔梯度的升高而呈增加趋势,表层土中含量多高于亚表层土;土壤中DOM组分均呈5个组分,即芳香蛋白类物质I(酪氨酸类,Peak I)、芳香蛋白类物质II(BOD5,Peak II)、富里酸类(Peak III)、微生物代谢产物(色氨酸类,Peak IV)和腐殖酸类(大分子腐殖酸,Peak V);高山土壤DOM中以富里酸类有机质和腐殖酸类有机质组分为主,FRI值均随着海拔的升高而降低..川西高山土壤DOM荧光特征参数(荧光指数FI、自生源指数BIX、腐殖化指数HIX、新鲜度指数β:α)表明,土壤DOM的稳定性随着海拔升高而降低,生物有效性随着海拔升高而升高.因此,气候变暖可能将导致高海拔土壤DOM分解加剧而含量降低,但稳定性升高. 相似文献
347.
348.
349.
Jin Zhang Fanhao Song Tingting Li Kefu Xie Huiying Yao Baoshan Xing Zhongyu Li Yingchen Bai 《环境科学学报(英文版)》2020,32(4):310-320
Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with the fluorescence regional integration(FRI),parallel factor(PARAFAC) analysis,and multi-order kinetic models.In the FRI analysis,fulvic-like and humic-like materials were the main constituents for both BH-FDOM and HF-FDOM.Four individual components were identified by use of PARAFAC analysis as humic-like components(C1),fulvic-like components(C2),protein-like components(C3) and unidentified components(C4).The maximum 3 DEEM fluorescence intensity of PARAFAC components C1-C3 decreased by about 60%,70% and 90%,respectively after photo-degradation.The multi-order kinetic model was acceptable to represent the photo-degradation of FDOM with correlation coefficient(R_(adj)~2)(0.963-0.998).The photo-degradation rate constants(k_n) showed differences of three orders of magnitude,from 1.09 x 10~(-6) to 4.02 x 10~(-4) min-1,and half-life of multi-order model(T_(1/2)~n)ranged from 5.26 to 64.01 min.The decreased values of fluorescence index(FI) and biogenic index(BI),the fact that of percent fluorescence response parameter of Region I(P_(Ⅰ,n)) showed the greatest change ratio,followed by percent fluorescence response parameter of Region II(P_(Ⅱ,n),while the largest decrease ratio was found for C3 components,and the lowest T_(1/2)~n was observed for C3,indicated preferential degradation of protein-like materials/components derived from biological sources during photodegradation.This research on the degradation of FDOM by 3 DEEM/FRI-PARAFAC would be beneficial to understanding the photo-degradation of FD OM in natural environments and accurately predicting the environmental behaviors of contaminants in the presence of FDOM. 相似文献
350.
Hale SS Miglarese AH Bradley MP Belton TJ Cooper LD Frame MT Friel CA Harwell LM King RE Michener WK Nicolson DT Peterjohn BG 《Environmental monitoring and assessment》2003,81(1-3):133-148
Understanding the ecology, condition, and changes of coastal areas requires data from many sources. Broad-scale and long-term ecological questions, such as global climate change, biodiversity, and cumulative impacts of human activities, must be addressed with databases that integrate data from several different research and monitoring programs. Various barriers, including widely differing data formats, codes, directories, systems, and metadata used by individual programs, make such integration troublesome. Coastal data partnerships, by helping overcome technical, social, and organizational barriers, can lead to a better understanding of environmental issues, and may enable better management decisions. Characteristics of successful data partnerships include a common need for shared data, strong collaborative leadership, committed partners willing to invest in the partnership, and clear agreements on data standards and data policy. Emerging data and metadata standards that become widely accepted are crucial. New information technology is making it easier to exchange and integrate data. Data partnerships allow us to create broader databases than would be possible for any one organization to create by itself. 相似文献