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Industrial eco-efficiency and its spatial-temporal differentiation in China

Wei YANG, Fengjun JIN, Chengjin WANG, Chen LV

《环境科学与工程前沿（英文）》 2012年第6卷第4期页码 559-568 doi: 10.1007/s11783-012-0400-4

摘要： The aim of this paper is to study the spatial-temporal differentiation of industrial eco-efficiency in China. Using methods based on the data envelopment analysis (DEA) model and exploratory spatial data analysis (ESDA) and data from 1985, 1995, 2005, and 2008 of 30 provinces in China, the spatial-temporal pattern changes in industrial eco-efficiency are discussed. The results show that: first, the patterns of industrial eco-efficiency are dominated by clustering of relatively low efficiency provinces; second, spatial relationships between the industrial eco-efficiencies of different provinces changed slightly throughout the period and the provinces persistently exhibit spatial concentration of relatively low industrial eco-efficiency; finally, there is an obvious trend in the polarization of industrial eco-efficiency, i.e., the higher level spatial units are concentrated in eastern China, and the lower level spatial units are mainly in western and central China.

关键词： industrial eco-efficiency data envelopment analysis (DEA) model exploratory spatial data analysis (ESDA)

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Using hydrochemical signatures to characterize the long-period evolution of groundwater information in the Dagu River Basin, China

《环境科学与工程前沿（英文）》 2021年第15卷第5期 doi: 10.1007/s11783-021-1393-7

摘要：

• The long-period groundwater evolution was identified by hydrochemical signatures.

关键词： Groundwater quality Hydrochemical signatures Spatial-temporal variations Water-rock interactions Anthropogenic interventions

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Assessment of temporal and spatial variations in water quality using multivariate statistical methods

Xue LI,Pengjing LI,Dong WANG,Yuqiu WANG

《环境科学与工程前沿（英文）》 2014年第8卷第6期页码 895-904 doi: 10.1007/s11783-014-0736-z

摘要： This study evaluated the temporal and spatial variations of water quality data sets for the Xin'anjiang River through the use of multivariate statistical techniques, including cluster analysis (CA), discriminant analysis (DA), correlation analysis, and principal component analysis (PCA). The water samples, measured by ten parameters, were collected every month for three years (2008–2010) from eight sampling stations located along the river. The hierarchical CA classified the 12 months into three periods (First, Second and Third Period) and the eight sampling sites into three groups (Groups 1, 2 and 3) based on seasonal differences and various pollution levels caused by physicochemical properties and anthropogenic activities. DA identified three significant parameters (temperature, pH and ) to distinguish temporal groups with close to 76% correct assignment. The DA also discovered five parameters (temperature, electricity conductivity, total nitrogen, chemical oxygen demand and total phosphorus) for spatial variation analysis, with 80.56% correct assignment. The non–parametric correlation coefficient (Spearman R) explained the relationship between the water quality parameters and the basin characteristics, and the GIS made the results visual and direct. The PCA identified four PCs for Groups 1 and 2, and three PCs for Group 3. These PCs captured 68.94%, 67.48% and 70.35% of the total variance of Groups 1, 2 and 3, respectively. Although natural pollution affects the Xin'anjiang River, the main sources of pollution included agricultural activities, industrial waste, and domestic wastewater.

关键词： Xin'anjiang River multivariable statistical analysis temporal variation spatial variation water quality

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Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

《环境科学与工程前沿（英文）》 2015年第9卷第4期页码 649-664 doi: 10.1007/s11783-014-0702-9

摘要： Fuzzy comprehensive assessment and multivariate statistical techniques including cluster analysis, discriminant analysis, principal component analysis, and factor analysis were applied to analyze the water quality status of Yuqiao Reservoir Basin, North China, for assessing its spatio-temporal variations and identifying potential pollution sources. In this paper, we considered data for 14 water quality parameters collected during 1990–2004 at 7 water quality monitoring sites. The results of fuzzy comprehensive assessment revealed that water quality in Yuqiao Reservoir Basin showed a downtrend from 1990 to 2001 with fluctuation, and a slowly upward trend after 2001. The major water quality belonged to Class III and IV. Besides, hierarchical cluster analysis divided 7 monitoring sites into two groups (Group A and B), and 12 months into three periods (low-flow (LF), normal-flow (NF), and high-flow (HF) period). Temp, pH, SS, T-har, DO, NO -N and TP were identified as significant variables affecting spatial variations, and Temp, pH and NO -N were identified as significant variables affecting temporal variations by discriminant analysis. Factor analysis identified four latent pollution sources for water quality variations: nutrient pollution, organic pollution, inorganic pollution, and natural pollution. Moreover, for Group A regions, pollution inputs mainly came from domestic wastewater and industrial sewage. For Group B regions, it is more likely that water pollution resulted from the combined effects of domestic wastewater, hospital wastewater, agriculture runoff, and fishpond discharge, as well as the incoming water from upstream.

关键词： Fuzzy comprehensive assessment multivariate statistical analysis water quality

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Spatial and Temporal Distribution of PM

Xiao-hong Chen,Xiang-bo Tang

《工程管理前沿（英文）》 2016年第3卷第2期页码 171-181 doi: 10.15302/J-FEM-2016017

摘要： Utilizing the initial hourly monitoring data of PM concentrations at 23 monitoring sites across the Chang-Zhu-Tan city cluster between January 2013 and February 2014 that released in Real-time Air Quality Reporting System in Hunan Province, this paper draws diagrams and analyzes the change rule of the pollutants concentration over time. In addition, this paper studies the regional distribution of PM seasonal pollution in the vicinity of the monitoring sites using ArcGIS geographic information system with the Kriging interpolation method. On this basis, this paper puts forward some effective control strategies to cope with regional PM pollution combined with the information of industry distribution and development status in the Chang-Zhu-Tan city cluster.

关键词： PM_2.5 spatial and temporal distribution ArcGIS the chang-Zhu-Tan city cluster

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我国一次气溶胶和二次无机气溶胶大气年龄的时空分布特征 Article

Xiaodong Xie, Qi Ying, 张宏亮, 胡建林

《工程（英文）》 2023年第28卷第9期页码 117-129 doi: 10.1016/j.eng.2022.03.013

摘要：

颗粒物的老化时间尺度是确定其对空气质量、人类健康和气候影响的关键参数。本研究使用年龄可分辨的社区多尺度空气质量模型CMAQ对我国一次和二次无机细颗粒物（PM_2.5）的年龄分布进行了为期一年的模拟。结果表明，一次PM_2.5（PPM）和铵盐主要来源于本地的新鲜排放，我国大部分地区约60%~80%集中在0~24 h年龄档。夏季，大多数地区的平均年龄约为15~25 h，但冬季，我国南部地区和四川盆地（SCB）的平均年龄增加到40~50 h。硫酸盐的大气年龄明显大于PPM，表明区域输送的贡献增加。在大多数地区和季节，大气年龄> 48 h的老化硫酸盐占硫酸盐总质量浓度的30%~50%。冬季SCB地区年龄> 96 h的硫酸盐浓度可达15 µg·m⁻³。长三角、珠三角和华南地区硫酸盐大气年龄的季节变化较大，冬季的平均年龄最高为60~70 h，夏季最低为40~45 h。夏季硝酸盐的平均年龄为20~30 h，冬季增加至40~50 h。夏季，气态硝酸的占比增加导致总硝酸的沉降速率的增大；同时，更强的大气氧化性加快了氮氧化物向硝酸盐的化学转化速率，从而导致夏季硝酸盐的大气年龄较低。此外，在污染天，大多数城市和季节中老化粒子（> 24 h）对PPM和二次无机气溶胶的贡献明显增加，这表明区域输送在重污染事件中发挥着至关重要的作用。本研究中基于年龄可分辨的CMAQ模型得到的PM_2.5年龄信息可以帮助政府部分制定有效的应急排放控制措施，有助于消除重污染天气。

关键词：大气年龄 PM_2.5 CMAQ模型控制措施

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空中交通延误传播动力学的时空网络视角 Article

Qing Cai, Sameer Alam, Vu N. Duong

《工程（英文）》 2021年第7卷第4期页码 452-464 doi: 10.1016/j.eng.2020.05.027

摘要：

由于日益增长的空中交通需求与有限的空域容量之间的不平衡，空中交通出现了难以解决的延误。由于空中交通与复杂的航空运输系统有关，延误可以在这些系统中被放大和传播，从而导致所谓的延迟传播的紧急行为。对延误传播动力学的理解与现代空中交通管理有着密切的关系。本文提出了一种复杂的网络延迟传播动力学观点。具体来说，我们利用以机场为节点的时空网络对空中交通场景进行建模。为了建立节点间的动态边缘，我们提出了一种时延传播方法，并将其应用于给定的空中交通调度集合。基于所构建的时空网络，提出了三个指标（幅度、严重性和速度）来衡量延迟传播动态。为了验证该方法的有效性，我们对东南亚地区（SAR）和美国的国内航班进行了案例研究。实验表明，美国交通延误传播影响的航班数和传播延迟量的传播幅度分别是SAR的5倍和10倍。实验进一步表明，美国交通的传播速度比SAR快8倍。延迟传播动态显示，SAR约6个枢纽机场存在明显的传播延误，而美国的情况则更为严重，相应数量在16个左右。本工作为跟踪空中交通延误的演变提供了有力的工具。

关键词：空中交通运输系统时延传播动力学时空网络

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Temporal and spatial stability of the EM/PM molecular subtypes in adult diffuse glioma

《医学前沿（英文）》 2023年第17卷第2期页码 240-262 doi: 10.1007/s11684-022-0936-z

摘要： Detailed characterizations of genomic alterations have not identified subtype-specific vulnerabilities in adult gliomas. Mapping gliomas into developmental programs may uncover new vulnerabilities that are not strictly related to genomic alterations. After identifying conserved gene modules co-expressed with EGFR or PDGFRA (EM or PM), we recently proposed an EM/PM classification scheme for adult gliomas in a histological subtype- and grade-independent manner. By using cohorts of bulk samples, paired primary and recurrent samples, multi-region samples from the same glioma, single-cell RNA-seq samples, and clinical samples, we here demonstrate the temporal and spatial stability of the EM and PM subtypes. The EM and PM subtypes, which progress in a subtype-specific mode, are robustly maintained in paired longitudinal samples. Elevated activities of cell proliferation, genomic instability and microenvironment, rather than subtype switching, mark recurrent gliomas. Within individual gliomas, the EM/PM subtype was preserved across regions and single cells. Malignant cells in the EM and PM gliomas were correlated to neural stem cell and oligodendrocyte progenitor cell compartment, respectively. Thus, while genetic makeup may change during progression and/or within different tumor areas, adult gliomas evolve within a neurodevelopmental framework of the EM and PM molecular subtypes. The dysregulated developmental pathways embedded in these molecular subtypes may contain subtype-specific vulnerabilities.

关键词： glioma progression molecular classification EM/PM subtyping intratumor heterogeneity

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Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

《农业科学与工程前沿（英文）》 2017年第4卷第1期页码 69-80 doi: 10.15302/J-FASE-2017140

摘要： To explore the distribution of food demand and the projected trend in future food demand in China, this paper analyzed the change in current (1998–2012) per-capita demand for grain, grain-consuming and herbivorous livestock products, and predicted the food demand in 2020. The results indicated that in 1998–2012, the national per-capita consumption of grain ration declined by about 36.66%, and the per-capita consumption of grain-consu-ming and herbivorous livestock products increased by about 48% and 34.09%, respectively. The grain-consu-ming livestock products have become the primary source of both calories and protein for consumers. The proportion of herbivorous livestock products in consumer diets has increased steadily and there has been huge potential in substituting beef and mutton for pork in this dynamic market. The demand for food in different provinces of China is highly variable, which is important for planning grassland agriculture development and ensuring food safety. The demand for grain, and grain-consuming and herbivorous livestock products will increase by about 3.3%, 20% and 14% respectively by 2020. Based on the food demand and trend in the development of grassland agriculture, the 31 provinces in China are divided into three priority groups for grassland agriculture development.

关键词： arable land equivalent unit (ALEU) food equivalent unit (FEU) food security grassland agriculture time trend prediction

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Trends of environmental accidents and impact factors in China

Pengli XUE, Weihua ZENG

《环境科学与工程前沿（英文）》 2011年第5卷第2期页码 266-276 doi: 10.1007/s11783-010-0267-1

摘要： An overview of the spatial and temporal variations of the environmental accidents in China in recent years was presented in this paper using available data. The results showed that the frequency of pollution accidents was significantly decreased, from 3462 in 1990 to 462 in 2007. The water and air pollution accidents were found to be the dominant types, accounting for more than 80% of the total accidents. Considering the classification of environmental accidents at 4 scales, the general environmental accident, i.e., the least serious type, was the most frequent event, taking up 58.98% of the total pollution accidents. In addition, the distribution of environmental accidents was generally in accordance with the industrial layout in the country during the past decade. It is very important to note that the extraordinarily severe environmental accidents showed an increasing trend in underdeveloped regions, which was caused by the transfer and the development of heavy polluted industry in these areas. As to the losses of environmental accidents, the casualties presented an obvious reduction tendency, while the direct economic loss per accident tended to climb up. Furthermore, some key factors that affect the spatial and temporal tendencies of environmental accidents in China were discussed and some suggestions were put forward, hoping to shed light on environmental risk management and emergency plans making associated with environmental accidents in China.

关键词： environmental accidents spatial and temporal trends environmental risk

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High resolution satellite imaging sensors for precision agriculture

Chenghai YANG

《农业科学与工程前沿（英文）》 2018年第5卷第4期页码 393-405 doi: 10.15302/J-FASE-2018226

摘要：

The central concept of precision agriculture is to manage within-field soil and crop growth variability for more efficient use of farming inputs. Remote sensing has been an integral part of precision agriculture since the farming technology started developing in the mid to late 1980s. Various types of remote sensors carried on ground-based platforms, manned aircraft, satellites, and more recently, unmanned aircraft have been used for precision agriculture applications. Original satellite sensors, such as Landsat and SPOT, have commonly been used for agricultural applications over large geographic areas since the 1970s, but they have limited use for precision agriculture because of their relatively coarse spatial resolution and long revisit time. Recent developments in high resolution satellite sensors have significantly narrowed the gap in spatial resolution between satellite imagery and airborne imagery. Since the first high resolution satellite sensor IKONOS was launched in 1999, numerous commercial high resolution satellite sensors have become available. These imaging sensors not only provide images with high spatial resolution, but can also repeatedly view the same target area. The high revisit frequency and fast data turnaround time, combined with their relatively large aerial coverage, make high resolution satellite sensors attractive for many applications, including precision agriculture. This article will provide an overview of commercially available high resolution satellite sensors that have been used or have potential for precision agriculture. The applications of these sensors for precision agriculture are reviewed and application examples based on the studies conducted by the author and his collaborators are provided to illustrate how high resolution satellite imagery has been used for crop identification, crop yield variability mapping and pest management. Some challenges and future directions on the use of high resolution satellite sensors and other types of remote sensors for precision agriculture are discussed.

关键词： high resolution satellite sensor multispectral imagery precision agriculture spatial resolution temporal resolution

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Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

《环境科学与工程前沿（英文）》 2009年第3卷第2期页码 194-199 doi: 10.1007/s11783-009-0018-3

摘要： Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, I and I, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from I and I both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With I as the sample, the pair wise -tests also revealed that variations were minor between each pair of marine environments, with ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites ( ranging from 0.282 to 0.349).

关键词： terminal restriction fragment length polymorphism (T-RFLP) bacterial community structure marine microbial diversity HhaI MspI

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基于惯性能时空最优分布的高加速轻载机构精密定位方法 Article

陈新,白有盾,杨志军,高健,陈贡发

《工程（英文）》 2015年第1卷第3期页码 391-398 doi: 10.15302/J-ENG-2015063

摘要：

高速运动精密定位是微电子封装设备中高加速轻载执行机构的基本运动需求。本文推导了高加速机构瞬态非线性动力学响应方程，揭示了刚度、频率、阻尼 (与材料空间布局相关) 和驱动频率 (与运动规划相关) 是主要影响因素。据此，在满足高加速机构精密定位的条件下，笔者提出了一种基于最优非线性动力学响应的结构优化和速度规划新方法。在结构优化中，首先分析了目前流行的基于等效静态载荷的柔性多体动力学优化方法未充分考虑惯性载荷的不足，然后提出了基于等效模态的柔性多体动力学最优动态响应优化新方法；在速度规划上，针对传统的几何光滑方法不能反映系统动态特性的缺陷，提出了基于变边界条件非线性动力学响应优化的速度规划新方法。将所提方法应用到高速固晶焊头的优化设计中，通过结构优化，降低振幅超过20%，再经非对称变加速规划，缩短定位时间超过40%。本文提出的方法为微电子封装类装备等高加速轻载机构精密定位的实现提供了有效的理论支撑和解决途径。

关键词：高加速轻载机构精密定位时空分布惯性能等效静态载荷方法速度规划

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大鼠周围神经诱发脑皮层电位时空图——一种研究脑对周围神经反应模式的新方法 Article

殷晓峰, 邓玖旭, 陈博, 金博, 谷馨怡, 齐志丹, 冷坤鹏, 姜保国

《工程（英文）》 2022年第14卷第7期页码 147-155 doi: 10.1016/j.eng.2021.04.018

摘要：

将大脑作为一个整体，观察周围神经受到刺激后大脑反应的动态过程，是深入了解脑功能的基础，也是一个科学难题。本研究发展了一种新型大鼠脑皮层诱发电位微创正交记录方法，结果显示，在该方法下，刺激大鼠正中神经、尺神经和桡神经及其分支，首次获得了可重复、具有不同波形特点、可辨别的脑皮层诱发电位图谱，并将其时空变化规律以可视化的方式呈现出来。此外本研究也记录了正中神经离断4个月后，大鼠脑皮层诱发电位的变化。结果表明，大脑皮层对周围神经刺激的反应具有精确和可重复的时空顺序。本实验方法和波形图谱可作为测试平台用于探索周围神经系统和脑中枢神经系统之间的整体功能交互与动态重塑的时相机制。

关键词：周围神经大脑诱发皮层电位时空图谱