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Understanding high-emitting households in the UK through a cluster analysis

Xinfang WANG, Ming MENG

《能源前沿（英文）》 2019年 第13卷 第4期   页码 612-625 doi: 10.1007/s11708-019-0647-6

摘要： Anthropogenic climate change is a global problem that affects every country and each individual. It is largely caused by human beings emitting greenhouse gases into the atmosphere. In general, a small percentage of the population is responsible for a large amount of emissions. This paper focuses on high emitters and their CO emissions from energy use in UK homes. It applies a cluster approach, aiming to identify whether the high emitters comprise clusters where households in each cluster share similar characteristics but are different from the others. The data are mainly based on the Living Cost and Food survey in the UK. The results show that after equivalising both household emissions and income, the high emitters can be clustered into six groups which share similar characteristics within each group, but are different from the others in terms of income, age, household composition, category and size of the dwelling, and tenure type. The clustering results indicate that various combinations of socioeconomic factors, such as low-income single female living in an at least six-room property, or high-income retired couple owning a large detached house, could all lead to high CO emissions from energy use at home. Policymakers should target each high-emitter cluster differently to reduce CO emissions from energy consumption at home more effectively.

关键词： cluster analysis     emissions reduction     energy use     high emitters     household energy consumption     socioeconomic factors    

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Determination of the principal factors of river water quality through cluster analysis method and its

Liang GUO, Ying ZHAO, Peng WANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 238-245 doi: 10.1007/s11783-011-0382-7

摘要： In this paper, an artificial neural network model was built to predict the Chemical Oxygen Demand (COD ) measured by permanganate index in Songhua River. To enhance the prediction accuracy, principal factors were determined through the analysis of the weight relation between influencing factors and forecasting object using cluster analysis method, which optimized the topological structure of the prediction model input items of the artificial neural network. It was shown that application of the principal factors in water quality prediction model can improve its forecasting skill significantly through the comparison between results of prediction by artificial neural network and the measurements of the COD . This methodology is also applicable to various water quality prediction targets of other water bodies and it is valuable for theoretical study and practical application.

关键词： water quality forecast     principal factor     cluster analysis method     artificial neural network    

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圆锥滚子轴承振动的灰色模糊聚类分析

刘劲军,夏新涛,张立红

《中国工程科学》 2008年 第10卷 第7期   页码 112-117

摘要：

以30204型圆锥滚子轴承试验数据为基础，利用灰色模糊聚类分析方法对影响圆锥滚子轴承振动的 因素进行了综合分析，将圆锥滚子轴承各项参数按其对振动的影响分为三类：第一类对振动的影响最大，其 中包括滚子凸度、滚子直径偏差Dw 等参数；第二类对振动的影响较大，其中包括内滚道圆度，内滚道直线性 Li 等参数；第三类对振动的影响最小，其中包括内滚道波纹度，内滚道的角度偏差Δ２β 等参数。根据分类可 知，试验中圆锥滚子轴承的大部分参数都会对振动产生较大的影响。

关键词： 圆锥滚子轴承     振动     灰色模糊聚类分析    

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Cluster analysis for syndromes of real-world coronary heart disease with angina pectoris

Yufeng Zhao, Xueyun Yu, Xinyu Cao, Lin Luo, Liyun He, Shusong Mao, Li Ma, Peijing Rong, Yuxue Zhao, Guozheng Li, Baoyan Liu

《医学前沿（英文）》 2018年 第12卷 第5期   页码 566-571 doi: 10.1007/s11684-017-0556-1

摘要：

Syndromes of coronary heart disease with angina pectoris were analyzed to provide guidance for clinical practice and to improve accuracy of traditional Chinese medicine (TCM) diagnoses and efficacy of TCM treatment. A total of 860 cases with coronary heart disease with angina pectoris were selected from TCM Clinical Research Information Sharing System for TCM clinics and research. Syndromes were automatically extracted with the cluster method and were analyzed to provide objective evidence for clinical studies. Final syndrome classifications were recognized and confirmed by clinical experts. Popular syndromes included Qi and blood deficiency, blood stasis and obstruction collaterals, liver depression and spleen deficiency, and Qi stagnation and blood stasis. Syndromes Qi and blood deficiency and blood stasis and obstruction collaterals accounted for 28.61% of total syndromes, whereas liver depression and spleen deficiency and Qi stagnation and blood stasis accounted for 26.44%. The main syndrome elements comprised Qi deficiency, blood deficiency, blood stasis, and Qi stagnation.

关键词： syndrome differentiation     real-world study     coronary heart disease with angina pectoris     cluster analysis    

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Design of tandem genes cluster for isoflavone engineering

Xunli XIA PhD , Guangxiao YANG PhD , Guangyuan HE PhD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 292-296 doi: 10.1007/s11684-009-0057-y

摘要： In this paper, a universal effective novel method of constructing tandem genes cluster for isoflavone engineering was reported. A tandem genes cluster () of secondary metabolites of plant isoflavones was constructed by using the chalcone synthase (CHS), chalcone isomerase (CHI), and isoflavone synthase (IFS) (GenBank accession numbers EU526827, EU526829, EU526830) in only one recombination with the pET22b vector. The resulting expression vector pET- was heterogeneously expressed and co-incubated with barrenwort extractions, and the genistein-like component was detected.

关键词： isoflavones engineering     secondary metabolism     tandem genes cluster    

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Scaling up of cluster beam deposition technology for catalysis application

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1360-1379 doi: 10.1007/s11705-021-2101-7

摘要： Many research works have demonstrated that the combination of atomically precise cluster deposition and theoretical calculations is able to address fundamental aspects of size-effects, cluster-support interactions, and reaction mechanisms of cluster materials. Although the wet chemistry method has been widely used to synthesize nanoparticles, the gas-phase synthesis and size-selected strategy was the only method to prepare supported metal clusters with precise numbers of atoms for a long time. However, the low throughput of the physical synthesis method has severely constrained its wider adoption for catalysis applications. In this review, we introduce the latest progress on three types of cluster source which have the most promising potential for scale-up, including sputtering gas aggregation source, pulsed microplasma cluster source, and matrix assembly cluster source. While the sputtering gas aggregation source is leading ahead with a production rate of ~20 mg·h–1, the pulsed microplasma source has the smallest physical dimensions which makes it possible to compact multiple such devices into a small volume for multiplied production rate. The matrix assembly source has the shortest development history, but already show an impressive deposition rate of ~10 mg·h–1. At the end of the review, the possible routes for further throughput scale-up are envisaged.

关键词： nanoparticle     cluster     cluster beam deposition     magnetron sputtering     heterogeneous catalysis    

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面向制造企业的信息化评价方法

王慧明,齐二石,王慧敏

《中国工程科学》 2004年 第6卷 第8期   页码 86-90

摘要：

基于因子分析方法，对天津市51家制造企业的信息化状况进行定量的综合评价，并采用聚类分析方法对评价结果进行了分类，找出了各类企业的优势和不足，为企业信息化工作的开展提供了科学依据。

关键词： 制造企业信息化     因子分析     聚类分析    

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SHIFTING TO A RECOMMENDED DIETARY PATTERN COULD PROMOTE SUSTAINABLE DEVELOPMENT OF THE ENVIRONMENT AND HUMAN HEALTH

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 73-82 doi: 10.15302/J-FASE-2023489

摘要：

● Shifting from the existing dietary patterns to the alternative recommended dietary pattern could enhance the sustainable development of environment and human health.

关键词： CHNS data     cluster analysis     dietary patterns     sustainable development    

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Clustering economic sectors in China on a life cycle basis to achieve environmental sustainability

Sai LIANG, Tianzhu ZHANG, Xiaoping JIA

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 97-108 doi: 10.1007/s11783-012-0402-2

摘要： To improve material efficiency, industrial structure optimization becomes a focal point in Chinese industrial and environmental policies. It is crucial to cluster economic sectors and determine their priority for industrial and environmental policy implementation. Integrating a set of criteria, a hybrid input-output model and the hierarchical cluster analysis, this study clusters China’s economic sectors and determines their priority on a life cycle basis. China’s economic sectors are clustered into three clusters. Industrial structure changes (industrial policy) should encourage the development of sectors in cluster 1 and limit the development of sectors in cluster 2. Technology development and materials recycling (two environmental policies) should mainly focus on sectors in clusters 1 and 2. Future industrial policies in China should limit the development of two sectors named and . Instead of limiting some industries by command-and-control, the best policy option is to remedy environmental standards and law enforcement. Enterprises belonging to the identified key sectors from the viewpoint of direct production impacts should be concerned to achieve enterprise sustainability. To achieve sustainable production chains, the identified key sectors from the viewpoint of accumulative production impacts should be concerned. For sustainable consumption, the identified key sectors from the viewpoint of consumption impacts should be concerned to transform consumption styles. Most of environmental pressure can be alleviated not only by technical improvements and material recycling, but also by the development of economic sectors in cluster 1.

关键词： cluster analysis     input-output model     life cycle     material flow analysis     sustainable development    

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Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

João Pedro SANTOS,Christian CREMONA,André D. ORCESI,Paulo SILVEIRA,Luis CALADO

《结构与土木工程前沿（英文）》 2015年 第9卷 第1期   页码 1-16 doi: 10.1007/s11709-014-0277-3

摘要： A large amount of researches and studies have been recently performed by applying statistical and machine learning techniques for vibration-based damage detection. However, the global character inherent to the limited number of modal properties issued from operational modal analysis may be not appropriate for early-damage, which has generally a local character. The present paper aims at detecting this type of damage by using static SHM data and by assuming that early-damage produces dead load redistribution. To achieve this objective a data driven strategy is proposed, consisting of the combination of advanced statistical and machine learning methods such as principal component analysis, symbolic data analysis and cluster analysis. From this analysis it was observed that, under the noise levels measured on site, the proposed strategy is able to automatically detect stiffness reduction in stay cables reaching at least 1%.

关键词： structural health monitoring     early-damage detection     principal component analysis     symbolic data     symbolic dissimilarity measures     cluster analysis     numerical model     damage simulations    

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Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

《能源前沿（英文）》   页码 782-795 doi: 10.1007/s11708-023-0905-8

摘要： China is vigorously promoting the “whole county promotion” of distributed photovoltaics (DPVs). However, the high penetration rate of DPVs has brought problems such as voltage violation and power quality degradation to the distribution network, seriously affecting the safety and reliability of the power system. The traditional centralized control method of the distribution network has the problem of low efficiency, which is not practical enough in engineering practice. To address the problems, this paper proposes a cluster voltage control method for distributed photovoltaic grid-connected distribution network. First, it partitions the distribution network into clusters, and different clusters exchange terminal voltage information through a “virtual slack bus.” Then, in each cluster, based on the control strategy of “reactive power compensation first, active power curtailment later,” it employs an improved differential evolution (IDE) algorithm based on Cauchy disturbance to control the voltage. Simulation results in two different distribution systems show that the proposed method not only greatly improves the operational efficiency of the algorithm but also effectively controls the voltage of the distribution network, and maximizes the consumption capacity of DPVs based on qualified voltage.

关键词： distributed photovoltaics (DPVs)     cluster partitioning     improved differential evolution algorithm     voltage control     consumption capacity of distributed photovoltaics    

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A density functional theory study of methane activation on MgO supported NiM cluster: role of M on C–H

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1485-1492 doi: 10.1007/s11705-022-2169-8

摘要： Methane activation is a pivotal step in the application of natural gas converting into high-value added chemicals via methane steam/dry reforming reactions. Ni element was found to be the most widely used catalyst. In present work, methane activation on MgO supported Ni–M (M = Fe, Co, Cu, Pd, Pt) cluster was explored through detailed density functional theory calculations, compared to pure Ni cluster. CH4 adsorption on Cu promoted Ni cluster requires overcoming an energy of 0.07 eV, indicating that it is slightly endothermic and unfavored to occur, while the adsorption energies of other promoters M (M = Fe, Co, Pd and Pt) are all higher than that of pure Ni cluster. The role of M on the first C–H bond cleavage of CH4 was investigated. Doping elements of the same period in Ni cluster, such as Fe, Co and Cu, for C–H bond activation follows the trend of the decrease of metal atom radius. As a result, Ni–Fe shows the best ability for C–H bond cleavage. In addition, doping the elements of the same family, like Pd and Pt, for CH4 activation is according to the increase of metal atom radius. Consequently, C–H bond activation demands a lower energy barrier on Ni–Pt cluster. To illustrate the adsorptive dissociation behaviors of CH4 at different Ni–M clusters, the Mulliken atomic charge was analyzed. In general, the electron gain of CH4 binding at different Ni–M clusters follows the sequence of Ni–Cu (–0.02 e) < Ni (–0.04 e) < Ni–Pd (–0.08 e) < Ni–Pt (–0.09 e) < Ni–Co (–0.10 e) < Ni–Fe (–0.12 e), and the binding strength between catalysts and CH 4 raises with the CH4 electron gain increasing. This work provides insights into understanding the role of promoter metal M on thermal-catalytic activation of CH4 over Ni/MgO catalysts, and is useful to interpret the reaction at an atomic scale.

关键词： CH4 dissociation     Ni–M     C–H bond activation     charge transfer    

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Monte Carlo simulation of the diffusion-limited aggregating process of particle suspension systems

Jiajing XU, Lin ZHANG, Yongjian TANG, Wei DAI, Wenwen SHAN,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 270-274 doi: 10.1007/s11705-009-0273-7

摘要： The aggregating process of particle suspension systems is a very universal phenomena and crucial for various processes both in nature and in industry. In this paper, the aggregating process was simulated with off-lattice diffusion-limited cluster-cluster aggregation (DLCA) Monte Carlo programs. The self-similar fractal structures of aggregates have been clearly demonstrated by the statistical analysis of gyration radius distribution and the existence of a scaling distribution of the reduced cluster size. The fractal dimension determined from the relationship between mass and gyration radius of aggregates was 1.80 or so. The fractal dimension of the aggregates drawn from the radial distribution function and structure factor of a single aggregate is about 1.90–2.10. It was also showed that, along with the increasing of particle volume fraction, the fractal dimension will increase in a nearly square root manner, and the spatial range of the fractal structure appearing becomes narrower. Also, the gelation transition can only occur in a particle suspension system where the particle volume fraction is greater than a critical value.

关键词： cluster-cluster aggregation     distribution function     relationship     process     universal    

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Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China

Jiaquan ZHANG, Shihua QI, Xinli XING, Lingzhi TAN, Wei CHEN, Ying HU, Dan YANG, Chenxi WU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 177-183 doi: 10.1007/s11783-011-0354-y

摘要： Soil is an important source to other environmental media and organisms for organochlorine pesticides (OCPs) bioaccumulation. Twenty-four representative surface soil samples were collected from the lower reaches of the Jiulong River, China, in 2009. The concentrations of hexachlorocyclohexane isomers (HCHs) ranged from 0.38 to 39.52 ng·g , with a mean value of 9.51 ng·g . The concentrations of dichlorodiphenyltrichloroethanes (DDTs) and their metabolites were within the ranges of 0.94–700.99 ng·g , with a mean value of 71.17 ng·g . The concentrations of HCHs and DDTs in the soil were lower than the first grade level (50 ng·g ) of the Chinese Environmental Quality Standard (GB15618-1995). Hierarchical Cluster Analysis (HCA) and Pearson’s bivariate Correlations Analysis (PCA) were used to analyse the distribution and contamination levels of OCPs in this region. The results showed that DDTs were the major contaminants and there were no significant correlations between various OCPs concentrations and the total organic carbon (TOC) contents. A significant positive correlation was observed between HCHs and DDTs ( <0.01), which indicates that HCHs and DDTs may have similar sources and fate in the study area.

关键词： Jiulong River     hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethan (DDT)     classification     Hierarchical Cluster Analysis (HCA)     Pearson’s bivariate Correlations Analysis (PCA)    

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Heterometallic cluster-based organic frameworks as highly active electrocatalysts for oxygen reduction

《化学科学与工程前沿（英文）》 2023年 第17卷 第5期   页码 570-580 doi: 10.1007/s11705-022-2247-y

摘要： Recently, metal–organic frameworks are one of the potential catalytic materials for electrocatalytic applications. The oxygen reduction reaction and oxygen evolution reaction catalytic activities of heterometallic cluster-based organic frameworks are investigated using density functional theory. Firstly, the catalytic activities of heterometallic clusters are investigated. Among all heterometallic clusters, Fe2Mn–Mn has a minimum overpotential of 0.35 V for oxygen reduction reaction, and Fe2Co–Co possesses the smallest overpotential of 0.32 V for oxygen evolution reaction, respectively 100 and 50 mV lower than those of Pt(111) and RuO2(110) catalysts. The analysis of the potential gap of Fe2M clusters indicates that Fe2Mn, Fe2Co, and Fe2Ni clusters possess good bifunctional catalytic activity. Additionally, the catalytic activity of Fe2Mn and Fe2Co connected through 3,3′,5,5′-azobenzenetetracarboxylate linker to form Fe2M–PCN–Fe2M is explored. Compared with Fe2Mn–PCN–Fe2Mn, Fe2Co–PCN–Fe2Co, and isolated Fe2M clusters, the mixed-metal Fe2Co–PCN–Fe2Mn possesses excellent bifunctional catalytic activity, and the values of potential gap on the Mn and Co sites of Fe2Co–PCN–Fe2Mn are 0.69 and 0.70 V, respectively. Furthermore, the analysis of the electron structure indicates that constructing a mixed-metal cluster can efficiently enhance the electronic properties of the catalyst. In conclusion, the mixed-metal cluster strategy provides a new approach to further design and synthesize high-efficiency bifunctional electrocatalysts.

关键词： bimetallic metal–organic frameworks     bifunctional electrocatalyst     density functional theory     oxygen reduction reaction     oxygen evolution reaction    

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标题 作者 时间 类型 操作

Understanding high-emitting households in the UK through a cluster analysis

Xinfang WANG, Ming MENG

期刊论文

Determination of the principal factors of river water quality through cluster analysis method and its

Liang GUO, Ying ZHAO, Peng WANG

期刊论文

圆锥滚子轴承振动的灰色模糊聚类分析

刘劲军,夏新涛,张立红

期刊论文

Cluster analysis for syndromes of real-world coronary heart disease with angina pectoris

Yufeng Zhao, Xueyun Yu, Xinyu Cao, Lin Luo, Liyun He, Shusong Mao, Li Ma, Peijing Rong, Yuxue Zhao, Guozheng Li, Baoyan Liu

期刊论文

Design of tandem genes cluster for isoflavone engineering

Xunli XIA PhD , Guangxiao YANG PhD , Guangyuan HE PhD ,

期刊论文

Scaling up of cluster beam deposition technology for catalysis application

期刊论文

面向制造企业的信息化评价方法

王慧明,齐二石,王慧敏

期刊论文

SHIFTING TO A RECOMMENDED DIETARY PATTERN COULD PROMOTE SUSTAINABLE DEVELOPMENT OF THE ENVIRONMENT AND HUMAN HEALTH

期刊论文

Clustering economic sectors in China on a life cycle basis to achieve environmental sustainability

Sai LIANG, Tianzhu ZHANG, Xiaoping JIA

期刊论文

Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

João Pedro SANTOS,Christian CREMONA,André D. ORCESI,Paulo SILVEIRA,Luis CALADO

期刊论文

Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

期刊论文

A density functional theory study of methane activation on MgO supported NiM cluster: role of M on C–H

期刊论文

Monte Carlo simulation of the diffusion-limited aggregating process of particle suspension systems

Jiajing XU, Lin ZHANG, Yongjian TANG, Wei DAI, Wenwen SHAN,

期刊论文

Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China

Jiaquan ZHANG, Shihua QI, Xinli XING, Lingzhi TAN, Wei CHEN, Ying HU, Dan YANG, Chenxi WU

期刊论文

Heterometallic cluster-based organic frameworks as highly active electrocatalysts for oxygen reduction

期刊论文