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System and prospects of China’s intercity rail transit technology

Ming GONG

《机械工程前沿(英文)》 2018年 第13卷 第2期   页码 323-328 doi: 10.1007/s11465-018-0463-4

摘要:

City clusters and metropolitan areas in China are flourishing in the midst of the deepening urbanization in the country, thereby resulting in the emergence of intercity rail transit. Intercity railways connect mainline and urban railways for an integrated regional transportation system that underpins and leads the development of city clusters and metropolitan areas. This study explores the development mode and service characteristics of intercity rail transit, as well as proposes overviews on this system and prospects of its future technology in China.

关键词: intercity rail transit     city cluster     technical demand     technology system    

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: PM2.5     spatial and temporal distribution     ArcGIS     the chang-Zhu-Tan city cluster    

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    

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    

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    

Innovation Ecosystem for Green Smart City Building in China

Jin Chen

《工程管理前沿(英文)》 2015年 第2卷 第4期   页码 325-330 doi: 10.15302/J-FEM-2015058

摘要: Green Smart City (GSC), is one of the new types of cities which integrates eco-concepts and information technologies. As GSC construction is a resource intensive process, it requires a large amount of knowledge, information, talent and capital. Thus, setting up an innovation ecosystem is an astute way to promote the construction of a GSC. This paper, based on the case study by the Insigma Group, tries to explore the rules of innovation ecosystem building for the construction of GSCs in China.

关键词: green smart city     resource     innovation ecosystem building    

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    

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    

The development of roadside green swales in the Chinese Sponge City Program: Challenges and opportunities

《工程管理前沿(英文)》   页码 566-581 doi: 10.1007/s42524-023-0267-z

摘要: Roadside green swales have emerged as popular stormwater management infrastructure in urban areas, serving to mitigate stormwater pollution and reduce urban surface water discharge. However, there is a limited understanding of the various types, structures, and functions of swales, as well as the potential challenges they may face in the future. In recent years, China has witnessed a surge in the adoption of roadside green swales, especially as part of the prestigious Sponge City Program (SCP). These green swales play a crucial role in controlling stormwater pollution and conserving urban water resources by effectively removing runoff pollutants, including suspended solids, nitrogen, and phosphorus. This review critically examines recent research findings, identifies key knowledge gaps, and presents future recommendations for designing green swales for effective stormwater management, with a particular emphasis on ongoing major Chinese infrastructure projects. Despite the growing global interest in bioswales and their significance in urban development, China’s current classification of such features lacks a clear definition or specific consideration of bioswales. Furthermore, policymakers have often underestimated the adverse environmental effects of road networks, as reflected in existing laws and planning documents. This review argues that the construction and maintenance of roadside green swales should be primarily based on three critical factors: Well-thought-out road planning, suitable construction conditions, and sustainable long-term funding. The integration of quantitative environmental standards into road planning is essential to effectively address the challenge of pollution from rainfall runoff. To combat pollution associated with roads, a comprehensive assessment of potential pollution loadings should be carried out, guiding the appropriate design and construction of green swales, with a particular focus on addressing the phenomenon of first flush. One of the major challenges faced in sustaining funds for ongoing maintenance after swale construction. To address this issue, the implementation of a green finance platform is proposed. Such a platform would help ensure the availability of funds for continuous maintenance, thus maximizing the long-term effectiveness of green swales in stormwater management. Ultimately, the findings of this review aim to assist municipal governments in enhancing and implementing future urban road designs and SCP developments, incorporating effective green swale strategies.

关键词: grass swale     infiltration swale     bioswale     wet swale     sponge city    

数字城市到智慧城市的思考与探索

李成名,刘晓丽

《中国工程科学》 2013年 第15卷 第5期   页码 4-7

摘要:

首先综述了构建权威、唯一、通用的数字城市地理空间框架的必要性,然后详细介绍了我国数字城市建设的总体思路、进展情况、发挥的作用及产生的影响。接下来,针对时代发展、技术进步和需求变化,论述了当前地理空间框架面临的全新发展机遇和挑战,以及存在的问题,明确指出了智慧城市阶段时空信息框架的建设目标与内容,展望了下一步技术突破的方向。

关键词: 数字城市     智慧城市     时空信息云平台    

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    

China’s Sponge City construction: A discussion on technical approaches

Haifeng Jia, Zheng Wang, Xiaoyue Zhen, Mike Clar, Shaw L. Yu

《环境科学与工程前沿(英文)》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0984-9

摘要: Since 2014, China has been implementing the Sponge City Construction initiative, which represents an enormous and unprecedented effort by any government in the world for achieving urban sustainability. According to preliminary estimates, the total investment on the Sponge City Plan is roughly 100 to 150 million Yuan (RMB) ($15 to $22.5 million) average per square kilometer or 10 Trillion Yuan (RMB) ($1.5 Trillion) for the 657 cities nationwide. The Sponge City Plan (SCP) calls for the use of natural processes such as soil and vegetation as part of the urban runoff control strategy, which is similar to that of low impact development (LID) and green infrastructure (GI) practices being promoted in many parts of the world. The SCP includes as its goals not only effective urban flood control, but also rainwater harvest, water quality improvement and ecological restoration. So far, the SCP implementation has encountered some barriers and challenges due to many factors. The present paper presents a review of those barriers and challenges, offers discussions and recommendations on several technical aspects such as control goals and objectives; planning/design and construction of LID/GI practices; performance evaluation. Several key recommendations are proposed on Sponge City implementation strategy, Site-specific regulatory framework and technical guidance, Product innovation and certification, LID/GI Project financing, LID/GI professional training and certification, public outreach and education. It is expected that the successful implementation of the SCP not only will bring about a sustainable, eco-friendly urbanization process in China, but also contribute enormously to the LID/GI research and development with the vast amount of relevant data and experiences generated from the Sponge City construction projects.

关键词: Low impact development (LID)     Green infrastructure (GI)     Sponge City     Barriers     Construction strategies    

Substance flow analysis for an urban drainage system of a representative hypothetical city in China

Hua BAI, Siyu ZENG, Xin DONG, Jining CHEN

《环境科学与工程前沿(英文)》 2013年 第7卷 第5期   页码 746-755 doi: 10.1007/s11783-013-0551-y

摘要: This paper discusses the use of substance flow analysis (SFA) as a tool to support quantified research on urban drainage systems. Based on the principle of mass balance, a static substance flow model is established to describe and examine the routes and intensities of water, chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) for a representative hypothetical city (RH city) in China, which is a devised and scaled city using statistical characteristics of urban circumstances at the national level. It is estimated that the annual flux of water, COD, TN and TP through the urban drainage system in 2010 was 55.1 million m , 16037.3 t, 1649.5 t and 209.7 t, respectively. The effluent of wastewater treatment plant (WWTP) was identified as the most important pathway for pollutant emissions, which contributed approximately 60% of COD, 65% of TN and 50% of TP to receiving water. During the wastewater treatment process, 1.0 million m , 7042.5 t, 584.2 t and 161.4 t of the four studied substances had been transmitted into sludge, meanwhile 3813.0 t of COD and 394.0 t of TN were converted and emitted to the atmosphere. Compared with the representative hypothetical city of 2000, urban population and the area of urban built districts had expanded by approximately 90% and 80% respectively during the decade, resulting in a more than threefold increase in the input of substances into the urban drainage system. Thanks to the development of urban drainage systems, the total loads of the city were maintained at a similar level.

关键词: substance flow analysis (SFA)     urban drainage system     representative hypothetical city (RH city)     water pollution control    

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    

Prevalence and causes of air pollution and lung cancer in Xuanwei City and Fuyuan County, Yunnan Province

null

《医学前沿(英文)》 2012年 第6卷 第2期   页码 217-220 doi: 10.1007/s11684-012-0192-8

标题 作者 时间 类型 操作

System and prospects of China’s intercity rail transit technology

Ming GONG

期刊论文

Spatial and Temporal Distribution of PM

Xiao-hong Chen,Xiang-bo Tang

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

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

Xinfang WANG, Ming MENG

期刊论文

Scaling up of cluster beam deposition technology for catalysis application

期刊论文

Innovation Ecosystem for Green Smart City Building in China

Jin Chen

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

期刊论文

The development of roadside green swales in the Chinese Sponge City Program: Challenges and opportunities

期刊论文

数字城市到智慧城市的思考与探索

李成名,刘晓丽

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

China’s Sponge City construction: A discussion on technical approaches

Haifeng Jia, Zheng Wang, Xiaoyue Zhen, Mike Clar, Shaw L. Yu

期刊论文

Substance flow analysis for an urban drainage system of a representative hypothetical city in China

Hua BAI, Siyu ZENG, Xin DONG, Jining CHEN

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

Prevalence and causes of air pollution and lung cancer in Xuanwei City and Fuyuan County, Yunnan Province

null

期刊论文