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Seasonal microbial community shift in a saline sewage treatment plant

Qingmei YAN, Xuxiang ZHANG, Tong ZHANG, Herbert H P FANG

《环境科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 40-47 doi: 10.1007/s11783-011-0304-8

摘要: Activated sludge was monthly sampled from a saline sewage treatment plant of Hong Kong (China) during June 2007 to May 2008 to analyze the microbial community shift along with environmental variations using denaturing gradient gel electrophoresis of polymerase chain reaction amplified 16S rDNA fragments. Environmental changes resulted into a seasonal microbial community shift characterized by alterations in species number and abundance in the sewage treatment plant. Correspondence analysis and cluster analysis on community structure profile showed that the 12 monthly samples fell into four groups, which is in accordance with season changing in Hong Kong. Canonical correspondence analysis revealed that and posed more significant effects on community structure than total phosphorus and total nitrogen, respectively. Compared with sludge retention time, influent total phosphorus had an inverse effect on the community structure shift, and chemical oxygen demand and showed a similar effects. Results of this study may contribute to the development of new knowledge involving the microbial community shift in sewage treatment plants.

关键词: sewage treatment plants     polymerase chain reaction (PCR)     denaturing gradient gel electrophoresis (DGGE)     canonical correspondence analysis     correspondence analysis    

Interaction and independence on methane oxidation of landfill cover soil among three impact factors: water, oxygen and ammonium

Pinjing HE, Na YANG, Wenjuan FANG, Fan Lü, Liming SHAO

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 175-185 doi: 10.1007/s11783-011-0320-8

摘要: To understand the influence patterns and interactions of three important environmental factors, i.e. soil water content, oxygen concentration, and ammonium addition, on methane oxidation, the soils from landfill cover layers were incubated under full factorial parameter settings. In addition to the methane oxidation rate, the quantities and community structures of methanotrophs were analyzed to determine the methane oxidation capacity of the soils. Canonical correspondence analysis was utilized to distinguish the important impact factors. Water content was found to be the most important factor influencing the methane oxidation rate and Type II methanotrophs, and the optimum value was 15% (w/w), which induced methane oxidation rates 10- and 6- times greater than those observed at 5% (w/w) and 20% (w/w), respectively. Ambient oxygen conditions were more suitable for methane oxidation than 3% oxygen. The addition of of ammonium induced different effects on methane oxidation capacity when conducted at low or high water content. With regard to the methanotrophs, Type II was sensitive to the changes of water content, while Type I was influenced by oxygen content. Furthermore, the methanotrophic acidophile, , was detected in soils with a pH of 4.9, which extended their known living environments.

关键词: quantitative polymerase chain reaction (PCR)     denaturing gradient gel electrophoresis (DGGE)     principal component analysis (PCA)     canonical correspondence analysis (CCA)    

PM2.5 over North China based on MODIS AOD and effect of meteorological elements during 2003‒2015

Youfang Chen, Yimin Zhou, Xinyi Zhao

《环境科学与工程前沿(英文)》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1202-8

摘要: The Taihang Mountains was the boundary between high and low pollution areas. There were one high value center for PM2.5 pollution and two low value centers. In 2004, 2009 and after 2013, PM2.5 concentration was relatively low. Over the past 40 years, PM2.5 pollution in North China has become increasingly serious and progressively exposes the densely populated areas to pollutants. However, due to limited ground data, it is challenging to estimate accurate PM2.5 exposure levels, further making it unfavorable for the prediction and prevention of PM2.5 pollutions. This paper therefore uses the mixed effect model to estimate daily PM2.5 concentrations of North China between 2003 and 2015 with ground observation data and MODIS AOD satellite data. The tempo-spatial characteristics of PM2.5 and the influence of meteorological elements on PM2.5 is discussed with EOF and canonical correlation analysis respectively. Results show that overall R2 is 0.36 and the root mean squared predicted error was 30.1 μg/m3 for the model prediction. Our time series analysis showed that, the Taihang Mountains acted as a boundary between the high and low pollution areas in North China; while the northern part of Henan Province, the southern part of Hebei Province and the western part of Shandong Province were the most polluted areas. Although, in 2004, 2009 and dates after 2013, PM2.5 concentrations were relatively low. Meteorological/topography conditions, that include high surface humidity of area in the range of 34°‒40°N and 119°‒124°E, relatively low boundary layer heights, and southerly and easterly winds from the east and north area were common factors attributed to haze in the most polluted area. Overall, the spatial distribution of increasingly concentrated PM2.5 pollution in North China are consistent with the local emission level, unfavorable meteorological conditions and topographic changes.

关键词: Aerosol optical depth     PM2.5     MODIS     Mixed effect model     Canonical correlation analysis    

拟共形映射图像特征匹配 Article

Chun-xue WANG, Li-gang LIU

《信息与电子工程前沿(英文)》 2017年 第18卷 第5期   页码 644-657 doi: 10.1631/FITEE.1500411

摘要: 本文展示了一种从两幅图像的候选匹配点集中选取几何一致匹配点组并排除离群数据(outliers)的全自动方法。在给出包含离群数据的尺度不变特征转换(Scale-invariant feature transform, SIFT)候选匹配点集合的前提下,本文旨在通过在全部微分同胚空间中搜索映射,选择匹配点子集以保留更多的几何信息。该问题可转化为包含Beltrami系数(BC)项和拟共形映射的约束最优化问题。该问题可通过变量分裂迭代算法有效求解。算法的迭代涉及线性系统和线性约束凸二次规划两子问题。本文算法简洁,对离群数据有鲁棒性。实验结果表明,与现有方法相比,本算法能够获得更多的正确匹配点。

关键词: 特征匹配;拟共形映射;分裂算法    

完全信息价值的影响图求解法及其应用

刘艳琼,陈英武

《中国工程科学》 2006年 第8卷 第8期   页码 45-49

摘要:

指出了翻转决策树法求解完全信息价值时可能存在问题的根本原因,提出完全信息价值在影响图中的本质表现为信息弧,并对Howard正则型影响图定义进行修正,进而系统分析了两种不同情形下基于影响图求解完全信息价值的思路。最后举例说明。

关键词: 完全信息价值     影响图     Howard正则型    

基于四元数傅里叶变换和线性正则变换的二维四元数信号采样定理 Research Articles

胡晓晓1,程冬2,高洁欣3

《信息与电子工程前沿(英文)》 2022年 第23卷 第3期   页码 463-478 doi: 10.1631/FITEE.2000499

摘要: 本文主要研究在不同形式四元数傅里叶变换和线性正则变换下有限带宽四元数函数的采样定理。证明了有限带宽四元数函数可通过它们的直接采样或经过微分和希尔伯特变换后的采样重构。此外,讨论了不同形式变换下不同类型采样公式之间的关系。首先,如果四元数函数有限带宽区域是关于原点对称的矩形区域,则不同形式四元数傅里叶变换下四元数采样公式具有相同形式;否则,采样公式是不同的。其次,利用双边四元数傅里叶变换和线性正则变换的关系,得到不同形式四元数线性正则变换下有限带宽四元数函数采样定理。再次,分析了采样公式的截断误差。最后,通过仿真展示采样公式的应用。

关键词: 四元数傅里叶变换;四元数线性正则变换;采样定理;部分和总体四元数希尔伯特变换;部分和总体广义四元数希尔伯特变换;截断误差    

一种低剖面双极化可编程双波束扫描天线阵列 Perspective

朱世超,宁远帆,褚宏波,肖培,李高升

《信息与电子工程前沿(英文)》 2023年 第24卷 第10期   页码 1504-1512 doi: 10.1631/FITEE.2300253

摘要: 提出一种基于全息控制理论的低剖面双极化双波束扫描天线阵列。巧妙设计辐射单元,以通过控制集成在每个单元上的PIN二极管的状态实现可重构极化和辐射相位调制。将一个72通道的串并联等幅同相馈电网络与辐射阵列集成,实现阵列的低剖面特性。通过设计直流偏置电路,利用单片机对天线阵列数字编码,实现波束的二维动态精确偏转。加工制作了一个2单元子阵列和一个6×12阵列,并对该天线系统的数字可控辐射方向图特性进行实验验证。该天线系统可以在11 GHz实现−30°至30°的波束扫描,步进扫描角为5°。该天线系统具有体积小、成本低、易于集成、波束控制准确等特点,在雷达系统、智能天线等领域具有广阔的应用前景。

基于主动学习的不确定性感知补标签查询 Perspective

刘圣源1,陈珂2,胡天磊1,毛云青3

《信息与电子工程前沿(英文)》 2023年 第24卷 第10期   页码 1497-1503 doi: 10.1631/FITEE.2200589

摘要: 许多主动学习方法假设学习者可便捷地向注释者询问训练数据的完整标注信息。这些方法主要试图通过最小化标注数量降低标注成本。然而,对于许多现实中的分类任务来说,精确标注实例仍然非常昂贵。为降低单次标注行为成本,本文试图解决一种新的主动学习范式,称为具有补标签的主动学习(ALCL)。ALCL学习器只针对样例特定类别提出是或否的问题。在收到标注者答案后,ALCL学习器获得一些有监督实例和更多具有补标签的训练实例,这些补标签仅表示对应标签与该实例无关。。ALCL具有两个挑战性问题:如何选择要查询的实例以及如何从这些补标签和普通标签中提取信息。针对第一个问题,在主动学习范式下提出一种基于不确定性的抽样策略。针对第二个问题,改进了一种已有的ALCL方法,同时适配了我们的抽样策略。在各种数据集上的实验结果验证了本文方法的有效性。

关键词: 主动学习;图片分类;弱监督学习    

基于孔径耦合微带结构馈电的单脉冲透射阵天线 Correspondence

寇娜1,2,3,余世星1,2,3,丁召1,2,3,张正平1,2,3

《信息与电子工程前沿(英文)》 2022年 第23卷 第3期   页码 502-510 doi: 10.1631/FITEE.2000547

摘要: 设计、加工、并测试了一款X波段单脉冲透射阵天线,该天线由平面透射阵和馈源天线组成,其中馈源天线集成了基于孔径耦合的微带结构以及和差网络。仿真和测试结果表明,所提单脉冲天线具有21.5 dBi主波束增益,副瓣电平值在−13.4 dB以下,交叉极化电平值小于−20 dB。此外,和波束与差波束在E面和H面的增益比值分别为5.6 dB和4 dB。该天线具有重量轻、成本低等优点,有望用于低成本动中通系统。

关键词: 孔径耦合;单脉冲天线;微带;透射阵列    

基于迁移学习与多视角感兴趣点的膝关节运动追踪网络 Article

王聪, 谢帅宁, 李康, 王重阳, 刘旭东, 赵亮, 蔡宗远

《工程(英文)》 2021年 第7卷 第6期   页码 881-888 doi: 10.1016/j.eng.2020.03.016

摘要:

近年来,深度学习为一种基于二维(2D)—三维(3D)配准技术以测量人体膝关节运动的方法,该方法提供了快速完成配准并增加捕捉范围的可能性。但这类方法受限于大量的数据需求,因此,我们提出了一种基于特征的迁移学习法,用于提取荧光透视影像的特征。通过三个受试者以及不到100对荧光透视影像,我们获得了40%的平均配准成功率。本研究提出的基于学习的配准方法,可在荧光透视影像数量有限时使用。

关键词: 2D—3D配准     机器学习     领域自适应     点对应    

15th International Congress for Stereology and Image Analysis 第十五届国际体视学与图像分析学术会议

会议日期: 2019年05月27日

会议地点: 丹麦/奥胡斯

主办单位: 国际体视学与图像分析学会(ISSIA)

Decomposition analysis applied to energy and emissions: A literature review

《工程管理前沿(英文)》 2023年 第10卷 第4期   页码 625-639 doi: 10.1007/s42524-023-0270-4

摘要: Decomposition analysis has been widely used to assess the determinants of energy and CO2 emissions in academic research and policy studies. Both the methodology and application of decomposition analysis have been largely improved in the past decades. After more than 50 years’ developments, decomposition studies have become increasingly sophisticated and diversified, and tend to converge internally and integrate with other analytical approaches externally. A good understanding of the literature and state of the art is critical to identify knowledge gaps and formulate future research agenda. To this end, this study presents a literature survey for decomposition analysis applied to energy and emission issues, with a focus on the period of 2016–2021. A review for three individual decomposition techniques is first conducted, followed by a synthesis of emerging trends and features for the decomposition analysis literature as a whole. The findings are expected to direct future research in decomposition analysis.

关键词: index decomposition analysis     structural decomposition analysis     production decomposition analysis     energy     CO2 emissions    

Flow, thermal, and vibration analysis using three dimensional finite element analysis for a flux reversal

B. VIDHYA,K. N. SRINIVAS

《能源前沿(英文)》 2016年 第10卷 第4期   页码 424-440 doi: 10.1007/s11708-016-0423-9

摘要: This paper presents the simulation of major mechanical properties of a flux reversal generator (FRG) viz., computational fluid dynamic (CFD), thermal, and vibration. A three-dimensional finite element analysis (FEA) based CFD technique for finding the spread of pressure and air velocity in air regions of the FRG is described. The results of CFD are mainly obtained to fine tune the thermal analysis. Thus, in this focus, a flow analysis assisted thermal analysis is presented to predict the steady state temperature distribution inside FRG. The heat transfer coefficient of all the heat producing inner walls of the machine are evaluated from CFD analysis, which forms the main factor for the prediction of accurate heat distribution. The vibration analysis is illustrated. Major vibration sources such as mechanical, magnetic and applied loads are covered elaborately which consists of a 3D modal analysis to find the natural frequency of FRG, a 3D static stress analysis to predict the deformation of the stator, rotor and shaft for different speeds, and an unbalanced rotor harmonic analysis to find eccentricity of rotor to make sure that the vibration of the rotor is within the acceptable limits. Harmonic analysis such as sine sweep analysis to identify the range of speeds causing high vibrations and steady state vibration at a mode frequency of 1500 Hz is presented. The vibration analysis investigates the vibration of the FRG as a whole, which forms the contribution of this paper in the FRG literature.

关键词: flux reversal generator     air velocity     computation fluid dynamics     thermal analysis     vibration analysis     finite element analysis    

标题 作者 时间 类型 操作

Seasonal microbial community shift in a saline sewage treatment plant

Qingmei YAN, Xuxiang ZHANG, Tong ZHANG, Herbert H P FANG

期刊论文

Interaction and independence on methane oxidation of landfill cover soil among three impact factors: water, oxygen and ammonium

Pinjing HE, Na YANG, Wenjuan FANG, Fan Lü, Liming SHAO

期刊论文

PM2.5 over North China based on MODIS AOD and effect of meteorological elements during 2003‒2015

Youfang Chen, Yimin Zhou, Xinyi Zhao

期刊论文

拟共形映射图像特征匹配

Chun-xue WANG, Li-gang LIU

期刊论文

完全信息价值的影响图求解法及其应用

刘艳琼,陈英武

期刊论文

基于四元数傅里叶变换和线性正则变换的二维四元数信号采样定理

胡晓晓1,程冬2,高洁欣3

期刊论文

一种低剖面双极化可编程双波束扫描天线阵列

朱世超,宁远帆,褚宏波,肖培,李高升

期刊论文

基于主动学习的不确定性感知补标签查询

刘圣源1,陈珂2,胡天磊1,毛云青3

期刊论文

基于孔径耦合微带结构馈电的单脉冲透射阵天线

寇娜1,2,3,余世星1,2,3,丁召1,2,3,张正平1,2,3

期刊论文

基于迁移学习与多视角感兴趣点的膝关节运动追踪网络

王聪, 谢帅宁, 李康, 王重阳, 刘旭东, 赵亮, 蔡宗远

期刊论文

15th International Congress for Stereology and Image Analysis 第十五届国际体视学与图像分析学术会议

2019年05月27日

会议信息

黄幼麟:Dynamic Consumer Preferences for Electric Vehicles — A Longitudinal Analysis(2020年7月12日)

2022年06月10日

会议视频

福田敏男:Bio Cell Analysis and Assembly by Micro and Nano Robotic Technology(2019年8月25日)

福田敏男(院士)

2021年01月20日

会议视频

Decomposition analysis applied to energy and emissions: A literature review

期刊论文

Flow, thermal, and vibration analysis using three dimensional finite element analysis for a flux reversal

B. VIDHYA,K. N. SRINIVAS

期刊论文