检索结果-南通市图书馆

Penetration Estimation of GMA Backing Welding Based on Weld Pool Geometry Parameters

Chinese Journal of Mechanical Engineering 2019年第3期32卷 134-144页

作者： Junfen huang Long Xue Jiqiang huang Yong Zou ke Ma Opto-Mechatronic Equipment Technology Beijing Area Major Laboratory Beijing Institute of Petrochemical Technology

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 parameter

关键词： Welding automation Passive vision sensing Weld pool geometry parameters Penetration state Mathematical model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

How about the reporting quality of case reports in nursing field?

引用

World Journal of Clinical Cases 2019年第21期7卷 3505-3516页

作者： ke-Lu Yang cun-cun Lu Yue Sun Yi-Tong Cai Bo Wang Yi Shang Jin-Hui Tian Evidence-Based Nursing Center School of NursingLanzhou UniversityLanzhou 730000Gansu ProvinceChina Evidence-Based Medicine Center School of Basic Medical SciencesLanzhou UniversityLanzhou 730000Gansu ProvinceChina Gansu Province Hospital Rehabilitation Center Lanzhou 730000Gansu ProvinceChina Lanzhou University Second Hospital Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND As a significantly important part of clinical practice,the professional nursing process can be advanced in many *** the fact that case reports are regarded to be of a lower quality grade in the hierarchy of evidence,one of the principles of evidence-based medicine is that decision-making should be based on a systematic summary of ***,the evidence on the reporting characteristics of case reports in the nursing field is *** To use the CARE guidelines to assess reporting quality and factors influencing the quality of case reports in the nursing *** Nursing science citation indexed(SCI-indexed)journals were identified from the professional *** of the identified journals was searched on their website for articles published before December ***-one sub-items on the CARE checklist were recorded as“YES”,“PARTLY”,or“NO”according to information reported by the included *** responses were assigned corresponding scores of 1,0.5,and 0,*** overall score was the sum of the 21 sub-items and was defined as“high”(more than 15),“medium”(10.5 to 14.5),and“low”(less than 10).The means,standard deviations,odds ratios(OR),and the associated 95%confidence interval(CI)were determined using Stata 12.0 *** Ultimately,184 case reports from 16 SCI-indexed journals were identified,with overall scores ranging from 6.5 to 18(mean=13.6±2.3).Of the included case reports,10.3%were regarded low-quality,52.7%were considered middle-quality,and 37%were regarded *** were statistical differences in the mean overall scores of the included case reports with funding versus those without funding(14.2±1.7 vs 13.6±2.4,respectively;P=0.4456)and journal impact factorke-away lessons)were

关键词： Systematic review Case reports Case report guidelines Nursing Reporting quality Science citation indexed journals

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Imprint of the ENSO on Rainfall and Latent Heating Variability over the Southern South China Sea from TRMM Observations

引用

Journal of Ocean University of China 2016年第2期15卷 219-231页

作者： WANG Lei huang ke State key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of Sciences Guangdong Province key Laboratory for Coastal Ocean Variation and Disaster Prediction Technologies College of Ocean and MeteorologyGuangdong Ocean University

Analyses of the Tropical Rainfall Measuring Mission （TRMM） datasets revealed a prominent interannual variation in the convective-stratiform rainfall and latent heating over the southern South China Sea （SCS） during the winter monsoon between 1998 and 2010. Although the height of maximum latent heating remained nearly constant at around 7km in all of the years, the year-to- year changes in the magnitudes of maximum latent heating over the region were noticeable. The interannual variations of the convee- tive-stratiform rainfall and latent heating over the southern SCS were highly anti-correlated with the Nifio-3 index, with more （less） rainfall and latent heating during La Nifia （El Nifio） years. Analysis of the large-scale environment revealed that years of active rain- fall and latent heating corresponded to years of large deep convergence and relative humidity at 600hPa. The moisture budget diag- nosis indicated that the interarmual variation of humidity at 600hPa was largely modulated by the vertical moisture advection. The year-to-year changes in rainfall over the southern SCS were mainly caused by the interannual variations of the dynamic component associated with anomalous upward motions in the middle troposphere, while the interannual variations of the thermodynamic com- ponent associated with changes in surface specific humidity played a minor role. Larger latent heating over the southern SCS during La Nifia years may possibly further enhance the local Hadley circulation over the SCS in the wintertime.

关键词： TRMM satellite rainfall latent heating southern South China Sea E1 Nifio-Southem Oscillation (ENSO)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation

引用

IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1239-1249页

作者： ke Li Shunyi Zhao Biao huang Fei Liu key Laboratory of Advanced Process Control for Light Industry(Ministry of Education) Institute of AutomationJiangnan UniversityWuxi 214122China Department of Chemical and Materials Engineering University of AlbertaEdmonton AB T6G 2G6Canada

In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally *** paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear *** high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense *** that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state ***,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing *** results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems.

关键词： filtering estimation error

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A user requirements-oriented privacy policy self-adaption scheme in cloud computing

引用

Frontiers of Computer Science 2023年第2期17卷 33-44页

作者： Changbo ke Fu XIAO Zhiqiu huang Fangxiong XIAO School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210003China College of computer science and technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Software Engineering Jinling Institute of TechnologyNanjing 210000China

In an ever-changing environment,Software as a Service(SaaS)can rarely protect users'*** able to manage and control the privacy is therefore an important goal for *** the participant of composite service is substituted,it is unclear whether the composite service satisfy user privacy requirement or *** this paper,we propose a privacy policies automatic update method to enhance user privacy when a service participant change in the composite ***,we model the privacy policies and service variation ***,according to the service variation rules,the privacy policies are automatically generated through the negotiation between user and service ***,we prove the feasibility and applicability of our method with the *** the service quantity is 50,ratio that the services variations are successfully checked by monitor is 81%.Moreover,ratio that the privacy policies are correctly updated is 93.6%.

关键词： cloud computing SaaS service privacy protec-tion privacy policies update

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Single photon sources with single semiconductor quantum dots

引用

Frontiers of physics 2014年第2期9卷 170-193页

作者： Guang-cun Shant Zhang-Qi Yin Chan Hung Shek Wei huang Department of Physics and Materials Science City University of Hong Kong Hong Kong SAR China The Fu Foundation School of Engineering and Applied Science Columbia University New York NY 10027 USA The Institute for Interdisciplinary Information Sciences (IHS) Tsinghua University Beijing 100084 China Singapore-Jiangsu Joint Research Center for Organic/Bio-electronics and Information Displays and Institute of Advanced Materials Nanjing University of Technology Nanjing 211816 China

In *** contribution, we briefly recall the basic concepts of quantum optics and properties of semicon- ductor quantum clot. （QD） which *** necessary to the nnderstanding of the physics of single-photon generation with single QDs. Firstly, we address the theory of quantmn emitter-cavity system, the fluorescence and optical properties of semiconductor QDs, and the photon statistics as well as opti- cal properties of the QDs. We then review the localizatioll of single semiconductor QDs in quantum confined optical microcavity systems to achieve their overall optical properties and perfornances in terms of strong coupling regime, elfieiency, directionality, and polarization control. Furthermore, we will discuss the recenl, progress on the fabrication of single photon sources, and various *** for embedding single QDs into mieroca,vities or photonic crystal nanoeavities and show how to ex- tend the wavelength range. We focus in part;icular on new generations of electrically driven QD single photon source leading to high repetition rates, efficiencies at elevated temperature operation. Besides strong eoupling regime, and high collection new development;s of room temperature sin- gle photon emission in the strong coupling regime are reviewed. The generation of indistinguishable photons and remaining challenges for pract ical single-photon sources are also discussed.

关键词： single-photon source quantum dot (QD) quantum optics photon correlation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deep drawing of cup shell by powder cavity flexible forming technology

引用

Journal of Central South University 2017年第4期24卷 766-772页

作者： XUE Ya-hong CHEN ke FAN cun-jie LUO Jun-ting Education Ministry key Laboratory of Advanced Forging and Stamping Technology and Science Yanshan UniversityQinhuangdao 066004China State key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

A forming method named powder cavity flexible forming was proposed. It is a forming technology which uses powder medium instead of rigid punch or die to form sheet metals. Cup shells were successfully obtained by this technology. The theoretical calculation equation of forming load was obtained through mechanical analysis and the stress state in cup shells was analyzed by finite element simulation. The results show that powder cavity flexible forming technology can improve the forming limit of sheet metal. Compared with rigid die forming process, the thickness reduction in the punch fillet area significantly decreases and the drawing ratio increases from 1.8 to 2.2. The thinning compressive stress in the bottom of cup shell emerges, which makes the bottom of the cup shell in three-dimensional stress state and the stress in punch fillet region decrease due to powder reaction force, which can effectively inhibit the sever thinning of the sheet and prevent the generation of fracture defects.

关键词： cup shell powder cavity flexible forming drawing finite element simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimization by orthogonal array design of ion-pair HPLC separation of the enzymatic hydrolysis products of yeast RNA

引用

Chinese Chemical Letters 2010年第12期21卷 1453-1456页

作者： Jie Hua ke Long huang School of Chemistry and Chemical Engineering Central South University Changsha 410083 China School of Chemistry and Chemical Engineering Hunan Institute of Science and Technology Yueyang 414000 China

The separation of enzymatic hydrolysis products of yeast RNA by ion-pair HPLC was studied.A modified chromatographic response function（MCRF） was proposed to appraise the effectiveness of chromatographic *** function takes the number of peaks,resolution and the retention time of the last peak into *** shows advantages for optimization of HPLC separation of complex *** orthogonal array design was used to separate the hydrolysate of yeast RNA and the optimal chromatographic conditions were obtained.

关键词： Chromatographic response function Orthogonal array design 5'-Phosphodiesterase Barley roots Nucleotides

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantitative relationship between flagellate abundance and suspended particle density in huanghai Sea and East China Sea in summer

引用

Acta Oceanologica Sinica 2006年第2期25卷 109-118页

作者： huang Lingfeng PAN ke GUO Feng Department of Oceanography ＆ Institute of Subtropical Oceanography Xiamen University Xiamen 361005 China State key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

An investigation was carried out in the huanghai Sea and the East China Sea to study the quantitative relationship between the abundance of flagellates and the density of suspended particles in the summer of 2001. The results show that the abundance of flagellates varies from 44-12 600 cell/cm^3, and flagellates sometimes constitutes a significant part of suspended particles. The size-spectra of suspended particles can be divided into four categories： flat spectrum, humped spectrum, plankton spectrum and mixed spectrum. In general, the abundance of flagellates varies in proportion to the density of suspended particles. However, their quantitative relations reveal different characteristics in the seawater samples of different types of particle-size spectrum. This is only a preliminary study of the quantitative relationship between flagellates and suspended particles, which might lead to a potential convenient approach to the estimation of flagellate abundance in the sea.

关键词： marine flagellates suspended particles particle-size spectra quantitative relationship

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Analysis of One-Dimensional Compression under a Wide Range of Stress with Densely Arrayed BPM

引用

Computer Modeling in Engineering & Sciences 2021年第6期127卷 1101-1117页

作者： Tao Zhang ke Xu Wenxiong huang College of Mechanics and Materials Hohai UniversityNanjing211100China School of Civil Engineering Xuchang UniversityXuchang461000China

In this paper,the densely arrayed bonded particle model is proposed for simulation of granular materials with discrete element method(DEM)considering particle *** model can solve the problem of pore calculation after the grains are crushed,and reduce the producing time of *** this work,several one-dimensional compressing simulations are carried out to investigate the effect of particle crushing on mechanical properties of granular materials under a wide range of *** results show that the crushing process of granular materials can be divided into four different stages according to er-logσy *** the end of the second stage,there exists a yield point,after which the physical and mechanical properties of specimens will change *** extremely high stress,particle crushing will wipe some initial information of specimens,and specimens with different initial gradings and void ratios present some similar *** crushing has great influence on grading,lateral pressure coefficient and compressibility of granular materials,and introduce extra irreversible volume deformation,which is necessary to be considered in modelling of granular materials in wide stress range.

关键词： Densely arrayed BPM particle crushing gradation curve lateral pressure coefficient compressibility extra volume deformation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：