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VoLTE网络跨Pool容灾方案研究设计与实现 预览
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作者 刘挺昕 侯华杰 马千 《电信工程技术与标准化》 2019年第2期23-28,共6页
核心网集中化、扁平化的组网特点,在实现资源共享、业务快速部署等方面具有优势的同时,机房、电源、承载网等环节成为核心网多网元同时故障的潜在隐患,网络传统的单板级、网元级、Pool级容灾技术和机制已无法应对其带来的重大影响。为... 核心网集中化、扁平化的组网特点,在实现资源共享、业务快速部署等方面具有优势的同时,机房、电源、承载网等环节成为核心网多网元同时故障的潜在隐患,网络传统的单板级、网元级、Pool级容灾技术和机制已无法应对其带来的重大影响。为了解决上述问题,通过多维风险分析和网络能力分析,提出容灾率算法,实现VoLTE网络Pool内资源容灾能力的量化判定。基于该算法构建跨Pool容灾模型,通过四级定损、场景预置、网络资源动态调用,实现VoLTE业务跨Pool网络容灾,强化VoLTE核心网容灾体系化保障能力,实现重大网络故障下的业务快速恢复。 展开更多
关键词 VoLTE POOL 容灾
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一种CSFB业务双活问题的解决方案 预览
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作者 柏洁 《信息通信》 2019年第2期252-253,共2页
CSFB是中国移动的一种过渡语音解决方案。在日常维护中,维护人员发现了一种CSFB业务双活现象,当CSFB用户在MSC POOL内其中一个端局有垃圾数据,且HSS中登记位置错误时,称为双活用户,双活用户主叫正常,但无法正常被叫。伴随CSFB用户快速发... CSFB是中国移动的一种过渡语音解决方案。在日常维护中,维护人员发现了一种CSFB业务双活现象,当CSFB用户在MSC POOL内其中一个端局有垃圾数据,且HSS中登记位置错误时,称为双活用户,双活用户主叫正常,但无法正常被叫。伴随CSFB用户快速发展,以及网络的频繁割接扩容,这种现象出现频率越来越高,严重影响了LTE语音业务感知。基于此,文章提出了一种CSFB业务双活问题的解决方案,在解决问题的同时,有效地提升了客户感知。 展开更多
关键词 客户感知 CSFB 业务双活 MSC POOL VOLTE
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Numerical Investigation of Transient Temperature Distribution during Ti-6Al-4V Selective Laser Melting
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作者 XING Xiaodong ZHOU Qiuyu +2 位作者 WANG Shiyuan WANG Liquan JIANG Fengchun 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第2期370-377,共8页
The transient temperature field in the powder bed has a crucial effect on the quality of parts fabricated using Selective Laser Melting(SLM). In this study, a finite element model is established regarding the variance... The transient temperature field in the powder bed has a crucial effect on the quality of parts fabricated using Selective Laser Melting(SLM). In this study, a finite element model is established regarding the variance of temperature-dependent thermal properties and transformation latent heat. The temperature distribution and melt pool dimensions of a laser scan track were obtained by varying multiple parameters(layer thickness, laser power and scan speed). The effects of transition of material state and heat source model are also analyzed in this paper. The finite element simulation results show that an increased laser power and/or decreased scan speed results in an elevated maximum temperature of the powder layer and a larger melt pool size. Furthermore, it is found that the maximum temperature is significantly lowered due to the heat diffusion into the previous sintered zone. The heat source model has to be selected properly according to the element size. 展开更多
关键词 Selective Laser MELTING TRANSIENT temperature field process parameters MELT POOL
A preliminary study on an upper ocean heat and salt content of the western Pacific warm pool region 预览
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作者 Xiaoxin Yang Xiaofen Wu +1 位作者 Zenghong Liu Chunxin Yuan 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期60-71,共12页
On the basis of Argo profile data of the temperature and salinity from January 2001 to July 2014, the spatial distributions of an upper ocean heat content(OHC) and ocean salt content(OSC) of the western Pacific warm p... On the basis of Argo profile data of the temperature and salinity from January 2001 to July 2014, the spatial distributions of an upper ocean heat content(OHC) and ocean salt content(OSC) of the western Pacific warm pool(WPWP) region and their seasonal and interannual variations are studied by a cyclostationary empirical orthogonal function(CSEOF) decomposition, a maximum entropy spectral analysis, and a correlation analysis.Probable reasons for variations are discussed. The results show the following.(1) The OHC variations in the subsurface layer of the WPWP are much greater than those in the surface layer. On the contrary, the OSC variations are mainly in the surface layer, while the subsurface layer varies little.(2) Compared with the OSC, the OHC of the WPWP region is more affected by El Ni?o-Southern Oscillation(ENSO) events. The CSEOF analysis shows that the OHC pattern in mode 1 has strong interannual oscillation, with eastern and western parts opposite in phase. The distribution of the OSC has a positive-negative-positive tripole pattern. Time series analysis shows that the OHC has three phase adjustments with the occurrence of ENSO events after 2007, while the OSC only had one such adjustment during the same period. Further analysis indicates that the OHC variations are mainly caused by ENSO events, local winds, and zonal currents, whereas the OSC variations are caused by much more complex reasons. Two of these, the zonal current and a freshwater flux, have a positive feedback on the OSC change in the WPWP region. 展开更多
关键词 ocean HEAT CONTENT SALT CONTENT the western Pacific WARM POOL ARGO data
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Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional stimulants
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作者 Alvyn P.Berg Ting-An Fang Hao L.Tang 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期111-118,共8页
Anthropogenic organics are known to be responsible for the formation of harmful disinfection byproducts (DBPs) in swimming pool water (SPW). The research explored an important scenario of SPW with no additional anthro... Anthropogenic organics are known to be responsible for the formation of harmful disinfection byproducts (DBPs) in swimming pool water (SPW). The research explored an important scenario of SPW with no additional anthropogenic organic input. With stimulations by residual chlorine or additional chlorine and extended incubation, the formation of DBPs, especially chlorofonn, was significantly induced. Similar observations were found by investigating synthetic SPW made with sweat and urine. The presence of urine led to a massive fbmiation of chloroform, as noted by an approximate 19-fbld increase after 165-day incubation with a shock chlorine dose. The research suggests that consistent residual chlorine and long water retention as two typical features of SPW could unlock the DBP fbnnation potential of anthropogenic organics. Thus, limiting the introduction of anthropogenic organics may not have an immediate effect on reducing DBP levels, because their reactions with chlorine can be slow and long-lasting. Pool management should prioritize on control of urine and improving air ventilation. This work is useful to deepen understandings about DBP formation in SPW and provide implications for pool management and prospective legislation. 展开更多
关键词 TRIHALOMETHANES Haloacetic acids CHLOROFORM Residual chlorine ANTHROPOGENIC ORGANICS SWIMMING pool water
Regulation of mitochondrial NAD pool via NAD~+ transporter 2 is essential for matrix NADH homeostasis and ROS production in Arabidopsis
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作者 Lilan Luo Yajun He +9 位作者 Yannan Zhao Qian Xu Jian Wu Haiyan Ma Hongyan Guo Lin Bai Jianru Zuo Jian-Min Zhou Hong Yu Jiayang Li 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第8期991-1002,共12页
Reactive oxygen species(ROS) play a crucial role in numerous biological processes in plants, including development, responses to environmental stimuli, and programmed cell death(PCD). Deficiency in MOSAIC DEATH 1(MOD1... Reactive oxygen species(ROS) play a crucial role in numerous biological processes in plants, including development, responses to environmental stimuli, and programmed cell death(PCD). Deficiency in MOSAIC DEATH 1(MOD1), a plastid-localized enoyl-ACP reductase essential for de novo fatty acid biosynthesis in Arabidopsis thaliana, leads to the increased malate export from chloroplasts to mitochondria, and the subsequent accumulation of mitochondria-generated ROS and PCD. In this study, we report the identification and characterization of a mod1 suppressor, som592. SOM592 encodes mitochondrion-localized NAD~+ transporter 2(NDT2). We show that the mitochondrial NAD pool is elevated in the mod1 mutant. The som592 mutation fully suppressed mitochondrial NADH hyper-accumulation, ROS production, and PCD in the mod1 mutant, indicating a causal relationship between mitochondrial NAD accumulation and ROS/PCD phenotypes. We also show that in wild-type plants, the mitochondrial NAD+uptake is involved in the regulation of ROS production in response to continuous photoperiod. Elevation of the alternative respiration pathway can suppress ROS accumulation and PCD in mod1, but leads to growth restriction. These findings uncover a regulatory mechanism for mitochondrial ROS production via NADH homeostasis in Arabidopsis thaliana that is likely important for growth regulation in response to altered photoperiod. 展开更多
关键词 MITOCHONDRIAL NAD POOL NAD~+ TRANSPORTER 2 mtROS
Penetration Estimation of GMA Backing Welding Based on Weld Pool Geometry Parameters 预览
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作者 Junfen Huang Long Xue +2 位作者 Jiqiang Huang Yong Zou Ke Ma 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期134-144,共11页
Penetration estimation is a prerequisite of the automation of backing welding based on vision sensing technology. However, the arc interference in welding process leads to the difficulties of extracting the weld pool ... Penetration estimation is a prerequisite of the automation of backing welding based on vision sensing technology. However, the arc interference in welding process leads to the difficulties of extracting the weld pool characteristic information, which brings great challenges to the penetration estimation. At present, most researches focus on the extraction of weld pool geometry parameters, and the visual sensing systems are complex in structure and complicated in the image processing algorithms. The research of penetration estimation based on weld pool geometry parameters is still in the exploratory stage. The purpose of this paper is to research the relationship between the weld pool geometry parameters and the penetration during backing welding and to estimate penetration using the weld pool geometry parameters. A passive vision sensing test system for gas metal arc (GMA) backing welding was established. An image processing algorithm was developed to extract the weld pool geometry parameters, namely, the area, maximum width and length, half-length, length-width ratio and advancing contact angle (simplified as AWP, MWWP, MLWP, HLWP, LWR and ACA, respectively). The corresponding relationships between the weld pool geometry parameters and the penetration state were explored by analysing their changes with the welding current and speed. The distribution of the weld pool geometry parameters corresponding to penetration was determined. When the AWP of the weld pool is within a certain range and the values of LWR and ACA are close to their maximum and minimum respectively, the penetration is in good condition. A mathematical model with the weld pool geometry parameters as independent variables and the back-bead width (the indicator of the penetration state) as a dependent variable was established based on multivariable linear regression analysis, and relevant statistical tests were carried out. Multivariable linear regression equations for the weld pool geometry parameters and the back-bead width were deduced according 展开更多
关键词 Welding automation PASSIVE vision sensing WELD POOL GEOMETRY PARAMETERS PENETRATION state Mathematical model
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High Above Sea Level
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《北京周报:英文版》 2019年第31期3-11,共9页
R&D Strength A total of 4.19 million people in China worked in research and development(R&D)in 2018,maintaining the world's largest pool of R&D personnel for six consecutive years,the National Bureau o... R&D Strength A total of 4.19 million people in China worked in research and development(R&D)in 2018,maintaining the world's largest pool of R&D personnel for six consecutive years,the National Bureau of Statistics(NBS)said on July 23.China's R&D spending was 1.97 trillion yuan($286 billion)in 2018,138times the amount in 1991,according to an NBS report. 展开更多
关键词 HIGH ABOVE SEA Level R&D Strength the world's LARGEST POOL
Supervised descent method for weld pool boundary extraction during fiber laser welding process 预览
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作者 赵耀邦 张登明 +1 位作者 吴远峰 杨长祺 《中国焊接:英文版》 EI CAS 2019年第1期6-10,共5页
In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainl... In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainless steel is welded by a 5kW high-power fiber laser and a high-speed camera is employed to capture the topside images of weld pools. Then we propose a robust visual-detection approach for the molten pool based on the supervised descent method. It provides an elegant framework for representing the outline of a weld pool and is especially efficient for weld pool detection in the presence of strong uncertainties and disturbances. Finally, welding experimental results verified that the proposed approach can extract the weld pool boundary accurately, which will lay a solid foundation for controlling the weld quality of fiber laser welding process. 展开更多
关键词 FIBER laser welding MOLTEN POOL supervised DESCENT method BOUNDARY extraction
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MATERIALS AND METHODS 预览
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《水稻科学:英文版》 CSCD 2019年第4期I0008-I0009,共2页
Rice germplasm A total of 208 indica P/TGMS lines were selected for analysis from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 2), and 100 typical indica and 100 japonica accessions to ... Rice germplasm A total of 208 indica P/TGMS lines were selected for analysis from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 2), and 100 typical indica and 100 japonica accessions to identify the indica/japonica component of them were also from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 5). 展开更多
关键词 RICE mid-term gene POOL JAPONICA Indica/Japonica RICE
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Analysis of Determinants for an Enhanced and Long-lasting Coastal Convective System by Means of a Case Study (26 July 2011) 预览
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作者 Jung-Tae LEE Dong-In LEE +1 位作者 Shingo SHIMIZU Cheol-Hwan YOU 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第12期1327-1339,共13页
A precipitation system developed continuously along the western coastline of the Korean Peninsula and created considerable precipitation both along the coast and inland on 26 July 2011. In this study, the causes for t... A precipitation system developed continuously along the western coastline of the Korean Peninsula and created considerable precipitation both along the coast and inland on 26 July 2011. In this study, the causes for this nearshore convective system are investigated from observations and the results of model experiments. Three-dimensional radar fields clearly show that a change of wind at the surface border played an important role in the development of the nearshore convection system. The simulation results, which are very similar to the observations, show that the surface border generated and maintained the convergence zone. The roughness change enhanced the convergence, and the interaction between the deepening cold pool and downward flow maintained the convergence zone. The surface mechanical discontinuity affected by the roughness change between sea and land formed the convergence (gradient of wind stress), which induced momentum transfer to the upper layer. The cold pool created a steep gradient of potential temperature and provided the reason for the propagated convergence zone with the downward flow. The maximum value of the surface change factor, which comprises the influencing factors for the long-lasting convective system, reflects the enhancement of the system at the coast. 展开更多
关键词 COASTAL precipitation ROUGHNESS convergence zone cold POOL propagation DOWNWARD flow
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Carbon cycle in response to residue management and fertilizer application in a cotton field in arid Northwest China 预览
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作者 ZHANG Peng-peng XU Shou-zhen +3 位作者 ZHANG Guo-juan PU Xiao-zhen WANG Jin ZHANG Wang-feng 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第5期1103-1119,共17页
Understanding the influence of farming practices on carbon(C) cycling is important for maintaining soil quality and mitigating climate change, especially in arid regions where soil infertility, water deficiency, and c... Understanding the influence of farming practices on carbon(C) cycling is important for maintaining soil quality and mitigating climate change, especially in arid regions where soil infertility, water deficiency, and climate change had significantly influenced on agroecosystem. A field experiment was set up in 2009 to examine the influence of residue management and fertilizer application on the C cycle in a cotton field in the Xinjiang Uygur Autonomous Region of Northwest China. The study included two residue management practices(residue incorporation(S) and residue removal(NS)) and four fertilizer treatments(no fertilizer(CK), organic manure(OM), chemical fertilizer(NPK), chemical fertilizer plus organic manure(NPK+OM)). Soil organic carbon(SOC) and some of its labile fractions, soil CO2 flux, and canopy apparent photosynthesis were measured during the cotton growing seasons in 2015 and 2016. The results showed that SOC, labile SOC fractions, canopy apparent photosynthesis, and soil CO2 emission were significantly greater in S+NPK+OM(residue incorporation+chemical fertilizer) than in the other treatments. Analysis of all data showed that canopy apparent photosynthesis and soil CO2 emission increased as SOC increased. The S+OM(residue incorporation+organic manure) and S+NPK+OM treatments were greater for soil C sequestration, whereas the other treatments resulted in soil C loss. The S+NPK treatment is currently the standard management practice in Xinjiang. The results of this study indicate that S+NPK cannot offset soil C losses due to organic matter decomposition and autotrophic respiration. Residue return combined with NPK fertilizer and organic manure application is the preferred strategy in arid regions for increasing soil C sequestration. 展开更多
关键词 residue fertilizer SOC pool CANOPY apparent PHOTOSYNTHESIS SOIL RESPIRATION SOIL C balance
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Welding deviation detection method based on weld pool image contour features 预览
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作者 朱彦军 吴志生 +1 位作者 李科 杨培新 《中国焊接:英文版》 EI CAS 2019年第2期35-44,共10页
Automatic on-line detection of welding deviation based on machine vision is one of the key technologies of arc welding robot tracking welding,in which obtaining high quality weld pool image and accurate welding deviat... Automatic on-line detection of welding deviation based on machine vision is one of the key technologies of arc welding robot tracking welding,in which obtaining high quality weld pool image and accurate welding deviation detection algorithm are two important steps of tracking welding.Through the research and analysis of the weld pool image of gas metal arc welding(GMAW),it was found that the weld pool contains abundant welding information.First,the average gray value of the weld pool image can reflect the interference degree of arc to weld pool image and the heat input of welding process.Secondly,the tip of the weld pool image contour can reflect the center of the groove gap.Finally,the horizontal distance between the center coordinate of the wire contour and the tip coordinate of the weld pool image contour can reflect the welding deviation.On the basis of analyzing the characteristics of weld pool image,this paper proposes a new method of weld seam deviation detection,which includes the collection of weld pool image,image preprocessing,contour extraction and deviation calculation.The results of the tests and analyses showed that the maximum error of the on-line welding deviation obtained was about 2 pixels(0.17 mm)when the welding speed was≤60 cm/min,and the algorithm was stable enough to meet the requirements of real-time deviation detection for I-groove butt welding.The method can be applied to the on-line automatic welding deviation detection of arc welding robot. 展开更多
关键词 I-groove WELD POOL IMAGE deviation DETECTION algorithm
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On the Study of Wave Propagation and Distributionin the Global Ocean 预览
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作者 LIU Min ZHAO Dongliang 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第4期803-811,共9页
Based on the simulation with SWAN wave model and data of ERA-Interim from 1979 to 2016, how the waves propagate globally and why swell pools distribute in the eastern ocean were investigated in this study. The simulat... Based on the simulation with SWAN wave model and data of ERA-Interim from 1979 to 2016, how the waves propagate globally and why swell pools distribute in the eastern ocean were investigated in this study. The simulation results show that waves from North Pacific and North Atlantic mainly propagate southeastward or southward and swells generated in Southern Ocean spread northeastward. The waves from high latitude regions spread along the east coast and encounter in the tropical Pacific and Atlantic to form swell fronts around equator and then turn eastward. As the weak wind field with numerous swell inflows, swell pools are gener- ally located on the eastern side of the ocean basin, where the swell index S are greater than 0.9 calculated using ERA-20C data for the period of 1981 2010. Another remarkable feature is that swell pools move southward and split into two parts in winter, while they move northward and merge together in summer. 展开更多
关键词 WAVE propagation SWAN SWELL FRONT SWELL POOL WAVE energy density
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Anisotropy in mechanical properties and corrosion resistance of 316L stainless steel fabricated by selective laser melting 预览
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作者 Xiao-qing Ni De-cheng Kong +5 位作者 Ying Wen Liang Zhang Wen-heng Wu Bei-bei He Lin Lu De-xiang Zhu 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第3期319-328,共10页
The corrosion behavior and mechanical properties of 316L stainless steel (SS) fabricated via selective laser melting (SLM) were clarified by potentiodynamic polarization measurements, immersion tests, and tensile expe... The corrosion behavior and mechanical properties of 316L stainless steel (SS) fabricated via selective laser melting (SLM) were clarified by potentiodynamic polarization measurements, immersion tests, and tensile experiments. The microstructural anisotropy of SLMed 316L SS was also investigated by electron back-scattered diffraction and transmission electron microscopy. The grain sizes of the SLMed 316L SS in the XOZ plane were smaller than those of the SLMed 316L SS in the XOY plane, and a greater number of low-angle boundaries were present in the XOY plane, resulting in lower elongation for the XOY plane than for the XOZ plane. The SLMed 316L was expected to exhibit higher strength but lower ductility than the wrought 316L, which was attributed to the high density of dislocations. The pitting potentials of the SLMed 316L samples were universally higher than those of the wrought sample in chloride solutions because of the annihilation of MnS or (Ca,Al)-oxides during the rapid solidification. However, the molten pool boundaries preferentially dissolved in aggressive solutions and the damage of the SLMed 316L in FeCl3 solution was more serious after long-term service, indicating poor durability. 展开更多
关键词 selective laser MELTING mechanical property corrosion resistance 316L STAINLESS steel ANISOTROPY MOLTEN POOL boundary
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What Can We Deal with 2019?Build the Flow Pool by Stores Themselves! 预览
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作者 Yang Ting 《日用化学品科学(英文版)》 2019年第1期23-24,共2页
In 2018,cosmetics stores no longer complained about the difficulty in doing business.Instead,it has been found that a fewer number of stores stuck to their business.Adopting the supermarket model for CS has just compl... In 2018,cosmetics stores no longer complained about the difficulty in doing business.Instead,it has been found that a fewer number of stores stuck to their business.Adopting the supermarket model for CS has just completed the function of commodity transfer.Therefore,the value of this channel has already been cannibalized by e-commerce.But the value of CS is not only reflected in commodity transfer but information transfer and service experience.If we look at the well-performed CS right now,they are either stores selling special goods or stores offering special service for shoppers to experience. 展开更多
关键词 FLOW POOL STORES Themselves
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一种生命线工程地震直接经济损失预测的改进算法 ——以水池和供水管网为例 预览
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作者 孙晨雨 郭恩栋 +2 位作者 李玉芹 于天洋 李倩 《世界地震工程》 CSCD 北大核心 2019年第4期182-189,共8页
生命线工程对区域内的经济和社会功能维系起到重要作用,一旦遭到地震破坏,将带来巨大的经济损失和诸多次生的负面影响。因此,生命线工程的地震损失评估工作是十分重要的。针对传统的生命线工程地震直接经济损失预测的计算方法时常会带... 生命线工程对区域内的经济和社会功能维系起到重要作用,一旦遭到地震破坏,将带来巨大的经济损失和诸多次生的负面影响。因此,生命线工程的地震损失评估工作是十分重要的。针对传统的生命线工程地震直接经济损失预测的计算方法时常会带来的缺乏区分度的问题,利用线性插值法,提出了一种改进公式。并以水池和供水管网为例,进行了计算和比对。证明了改进方法具有以下优点:能够克服传统方法缺乏区分度的问题,对某一地震破坏等级对应的震害指数的变化导致预测结果展现出足够的区分度;足够简便,不会带来过多的运算量上升;没有引入新的概念,能够较好地融入现有震害评估体系。 展开更多
关键词 生命线工程 水池 供水管网 地震直接经济损失分析 改进算法
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Effects of electrode configuration on electroslag remelting process of M2 high-speed steel ingot
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作者 Fu-xing Yin Yu Liang +3 位作者 Zhi-xia Xiao Jian-hang Feng Zhi-bin Xie Yong-wang Mi 《中国铸造:英文版》 SCIE 2019年第2期126-134,共9页
The electrode configuration determines the thermophysical field during the electroslag remelting(ESR) process and affects the final microstructure of the ingot. In this work, ingot with a diameter of 400 mm was prepar... The electrode configuration determines the thermophysical field during the electroslag remelting(ESR) process and affects the final microstructure of the ingot. In this work, ingot with a diameter of 400 mm was prepared with two electrode configuration modes of single power ESR process, namely one electrode(OE) and two series-connected electrodes(TSCE). Finite element simulation was employed to calculate the electromagnetic field, flow field and temperature field of the ESR system. The results show that the temperature of the slag pool and the metal pool of the TSCE process is lower and more uniform than that of the OE process.The calculated temperature distribution of the ingot could be indirectly verified from the shape of the metal pool by the experiment. The experimental results show that the depth of the metal pool in the OE ingot is about 160 mm, while the depth of the TSCE ingot is nearly 40 mm shallower than that of the OE ingot. Microstructural comparisons indicate that coarse eutectic carbides are formed in the center of the OE ingot, whereas more even eutectic carbides appear in the center of the TSCE ingot. In general, compared with the OE process, the TSCE process is preferred to remelt high speed steel ingots. 展开更多
关键词 ELECTROSLAG REMELTING metal POOL shape electromagnetic field EUTECTIC carbides high SPEED steel
HBV核酸筛查混检反应性拆分成功的多因素分析及预测的研究
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作者 蒋瑞馨 郝庆钦 +2 位作者 王庆辉 夏卫 钱惠忠 《中国输血杂志》 CAS 2019年第7期703-706,共4页
目的探讨影响HBV核酸筛查中混检(pool)反应性拆分成功的相关因素及其预测价值,为本站制定重复拆分标准改进血液筛查策略,降低输血残余风险提供依据。方法回顾性分析2017年1月-2018年12月本站罗氏HBV核酸筛查pool反应性标本,收集相应献... 目的探讨影响HBV核酸筛查中混检(pool)反应性拆分成功的相关因素及其预测价值,为本站制定重复拆分标准改进血液筛查策略,降低输血残余风险提供依据。方法回顾性分析2017年1月-2018年12月本站罗氏HBV核酸筛查pool反应性标本,收集相应献血者临床、实验室检查资料。采用逐步多因素Logistic回归分析筛选影响HBV核酸筛查pool反应性拆分成功的相关因素,并通过ROC曲线评价其预测拆分结果的价值。结果近2年本站罗氏核酸筛查系统共检测20 332 pool(约12 1962份无偿献血者标本),呈反应性的有199个(约占0.98%),拆分反应性的有123个,拆分成功率为59.80%。其中HBs Ag-/HBV DNA+感染无偿献血者119人,在性别、年龄和教育程度方面分布有差异(χ~2分别为8.46,71.61,7.41,P均<0.01)。多因素Logistic回归分析显示,仅Ct(HBV)是HBV核酸筛查pool反应性拆分成功的独立相关因素(OR:0.762,95%CI:0.654-0.889)。在拆分反应性与无反应性pool组间,Ct(HBV)差异为2.04(t=3.15,P<0.01)。Ct(HBV)可预测拆分结果(AUC=0.66),最佳临界值为36.6,敏感性为38.8%,特异性为96.3%,阳性预测值为93.75%,阴性预测值为52.03%;临界值为37时,敏感性为46.60%,特异性为81.3%,阳性预测值为78.26%,阴性预测值为51.18%。结论 Ct(HBV)能独立预测HBV核酸筛查pool反应性标本拆分结果,但效能较低,当≤37时可考虑重复拆分,将来可联合其它实验室检测最大限度降低输血残余风险。 展开更多
关键词 乙型肝炎病毒 核酸检测 混样检测 LOGISTIC回归分析 风险因素
用于手写汉字识别的文本分割方法 预览
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作者 雷鑫 李俊阳 +1 位作者 宋宇 赛琳伟 《智能计算机与应用》 2018年第2期126-128,共3页
本文提出了一种手写汉字文本的分割方法,填补了汉字识别领域在文本行分割方面的空白。本方法首先对预处理后的文本图片进行池化处理,然后运用并查集算法得到每行为一个连通区域,最后调整每行上下的孤立区域的归属,最终把多行文本图片分... 本文提出了一种手写汉字文本的分割方法,填补了汉字识别领域在文本行分割方面的空白。本方法首先对预处理后的文本图片进行池化处理,然后运用并查集算法得到每行为一个连通区域,最后调整每行上下的孤立区域的归属,最终把多行文本图片分割为单行,为后期的汉字列分割做准备。此方法虽然用行分割,但也为汉字的列分割提供了新的思路。 展开更多
关键词 手写汉字识别 池化 文本分割 并查集
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