资源类型

期刊论文 122

年份

2023 13

2022 13

2021 10

2020 8

2019 8

2018 14

2017 9

2016 6

2015 6

2014 4

2013 6

2012 4

2011 5

2010 3

2009 4

2008 3

2005 1

2002 1

2001 1

2000 1

展开 ︾

关键词

气候变化 12

区域气候模式 2

温室气体 2

碳中和 2

青藏高原 2

Aphanomyces euteiches 1

China TIMES模型 1

NO3-N 1

《联合国气候变化框架公约》(UNFCCC) 1

三碳经济 1

上游关键敏感区 1

东亚季风 1

中国 1

人为活动 1

人工气候 1

傅里叶变换 1

光周期 1

全气候新能源汽车 1

全球城市 1

展开 ︾

检索范围:

排序: 展示方式:

Nexus security: governance, innovation and the resilient city

Michael Bruce BECK, Rodrigo VILLARROEL WALKER

《环境科学与工程前沿(英文)》 2013年 第7卷 第5期   页码 640-657 doi: 10.1007/s11783-013-0549-5

摘要: Nexus security is a compound mix of ideas: reconciling human needs and wants with access to multiple resources; diversity of access to those resources and services; resilience in the face of weather- and climate-related variability; resilience likewise in the face of infrastructure failure; and the personal, individual sense of belonging. At the level of Systems Thinking there is a very close relationship between resilience in the behavior of natural (ecological) systems and resilience in the social dynamics of governance within communities, where such resilience establishes the viability of these communities over centuries, which in turn entails successful stewardship of the man-environment relationship. We use insights from this cross-system mapping — across natural, built, and human systems — to assess, first, the role of city governance in achieving nexus security (or not) and, second, the role of technological innovations in serving the same purpose. More specifically, eight principles, covering resilience and diversity of access to resources and services, are used to gauge security-enhancing features of city buildings and infrastructure. Case studies include new designs of resilient office blocks, nutrient (nitrogen and phosphorus) recovery systems for sanitation and wastewater treatment, and the reconstruction of urban parks for the provision of ecosystem services. Throughout the paper, matters of risk in the face of meteorological variability are prominent. We do not conclude, however, that the presence of risk implies nexus security.

关键词: cities as forces for good     climate variability     ecosystem services     energy and nutrient recovery     infrastructure failure     urban metabolism    

CLIMATE-CHANGE-INDUCED TEMPORAL VARIATION IN PRECIPITATION INCREASES NITROGEN LOSSES FROM INTENSIVE CROPPING

《农业科学与工程前沿(英文)》 2022年 第9卷 第3期   页码 457-464 doi: 10.15302/J-FASE-2022452

摘要:

● A simple model was used to evaluate how increasing temporal variability in precipitation influences crop yields and nitrogen losses.

关键词: crop yield     fertilizer timing     nitrogen loss     precipitation variability     toy model    

Soil spatial variability impact on the behavior of a reinforced earth wall

Adam HAMROUNI, Daniel DIAS, Badreddine SBARTAI

《结构与土木工程前沿(英文)》 2020年 第14卷 第2期   页码 518-531 doi: 10.1007/s11709-020-0611-x

摘要: This article presents the soil spatial variability effect on the performance of a reinforced earth wall. The serviceability limit state is considered in the analysis. Both cases of isotropic and anisotropic non-normal random fields are implemented for the soil properties. The Karhunen-Loève expansion method is used for the discretization of the random field. Numerical finite difference models are considered as deterministic models. The Monte Carlo simulation technique is used to obtain the deformation response variability of the reinforced soil retaining wall. The influences of the spatial variability response of the geotechnical system in terms of horizontal facing displacement is presented and discussed. The results obtained show that the spatial variability has an important influence on the facing horizontal displacement as well as on the failure probability.

关键词: reinforced earth wall     geosynthetic     random field     spatial variability     Monte Carlo simulation    

Fuel variability effect on flickering frequency of diffusion flames

Jizhao LI, Yang ZHANG

《能源前沿(英文)》 2009年 第3卷 第2期   页码 134-140 doi: 10.1007/s11708-009-0034-9

摘要: It is known that fuel variability of different gas suppliers may cause combustion instability in a gas turbine combustor. Mechanisms that control the time scale of the heat release oscillations and acoustic pressure perturbations are both physical and chemical in nature, and thus can be influenced by changes in fuel composition. The intent of this study is to investigate the fuel variability on the flickering frequency of diffusion flames in the hope of understanding some of the fundamental aspects of fuel variability effect on the dynamics of combustion. Experiments were conducted at atmospheric pressure with a matrix of methane and propane blends. An optical fibre system was applied to capture simultaneously the flame flickering at two different light frequencies (430 nm and 516 nm), which provided a means of comparing the chemistry change. It was found that the low frequency oscillation of flow and flame structures depended only weakly on the exit velocities of the fuel, while ambient conditions had a significant effect on flickering frequencies and spectrum. The results of using CH and C H as test fuels at different flow rates showed very little variations, with peak frequencies at 11-13 Hz. When the jet flame was not disturbed, harmonics to at least the third mode were obtained in most of these cases. However, the cases which included CH /C H splits of 90/10, 85/15 and 80/20 by volume showed that unstable flickering frequencies and flame harmonics were not observed. When a mixture of methane/propane at a ratio of 1:1 was used the peak flickering frequency was around 6 Hz, and slight disturbance in the environment would cause the harmonics to disappear. Mechanisms thought to produce changes in the dynamic response and frequency harmonics were discussed.

关键词: fuel variability     flickering frequency     diffusion flames     dynamics of combustion    

Treatment, residual chlorine and season as factors affecting variability of trihalomethanes in small

Roberta DYCK,Geneviève COOL,Manuel RODRIGUEZ,Rehan SADIQ

《环境科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 171-179 doi: 10.1007/s11783-014-0750-1

摘要: Seasonal variability in source water can lead to challenges for drinking water providers related to operational optimization and process control in treatment facilities. The objective of this study is to investigate seasonal variability of water quality in municipal small water systems (<3000 residents) supplied by surface waters. Residual chlorine and trihalomethanes (THM) were measured over seven years (2003–2009). Comparisons are made within each system over time, as well as between systems according to the type of their treatment technologies. THM concentrations are generally higher in the summer and autumn. The seasonal variability was generally more pronounced in systems using chlorination plus additional treatment. Chloroform, total THM (TTHM) and residual chlorine concentrations were generally lower in systems using chlorination plus additional treatment. Conversely, brominated THM concentrations were higher in systems using additional treatment. Residual chlorine was highest in the winter and lowest in the spring and summer. Seasonal variations were most pronounced for residual chlorine in systems with additional treatment. There was generally poor correlation between THM concentrations and concentrations of residual chlorine. Further study with these data will be beneficial in finding determinants and indicators for both quantity and variability of disinfection byproducts and other water quality parameters.

关键词: drinking water     residual chlorine     seasonal variability     small municipal systems     treatment technologies     trihalomethanes    

Quantifying and mapping spatial variability of Shanghai household carbon footprints

Shangguang YANG,Chunlan WANG,Kevin LO,Mark WANG,Lin LIU

《能源前沿(英文)》 2015年 第9卷 第1期   页码 115-124 doi: 10.1007/s11708-015-0348-8

摘要: Understanding the spatial variability of household carbon emissions is necessary for formulating sustainable and low-carbon energy policy. However, data on household carbon emissions is limited in China, the world’s largest greenhouse gases emitter. This study quantifies and maps household carbon emissions in Shanghai using a city-wide household survey. The findings reveal substantial spatial variability in household carbon emissions, especially in transport-related emissions. Low emission clusters are founded in Hongkou, Xuhui, Luwan, Jinshan, and Fengxian. High emission clusters are located in Jiading and Pudong. Overall, the spatial pattern of household carbon emissions in Shanghai is donut-shaped: lowest in the urban core, increasing in the surrounding suburban areas, and declining again in the urban fringe and rural regions. The household emissions are correlated with a number of housing and socioeconomic factors, including car ownership, type of dwelling, size of dwelling, age of dwelling, and income. The findings underscore the importance of a localized approach to low-carbon policy-making and implementation.

关键词: household carbon emissions     spatial variability     energy policy     Shanghai     China    

Distribution and temporal variability of the solar resource at a site in south-east Norway

Muyiwa S. ADARAMOLA

《能源前沿(英文)》 2016年 第10卷 第4期   页码 375-381 doi: 10.1007/s11708-016-0426-6

摘要: Globally, solar energy is expected to play a significant role in the changing face of energy economies in the near future. However, the variability of this resource has been the main barrier for solar energy development in most locations around the world. This paper investigated the distribution and variability of solar radiation using the a 10-year (2006 to 2015) data collected at Sørås meteorological station located at latitude 59° 39′ N and longitude 10° 47′E, about 93.3 m above sea level (about 30 km from Oslo), in south-eastern part of Norway. It is found that on annual basis, the total number of days with a global solar radiation of less than 1 kWh/(m ·d) is 120 days while the total number of days with an expected global solar radiation greater than 3 kWh/(m ·d) is 156 days (42.74%) per year. The potential energy output from a horizontally placed solar collector in these 156 days is approximately 75% of the estimated annual energy output. In addition, it is found that the inter-annual coefficient of variation of the global solar radiation is 4.28%, while that of diffuse radiation is 4.96%.

关键词: coefficient of variation     global solar radiation     diffuse ratio     albedo     PV energy systems    

ClimateAP: an application for dynamic local downscaling of historical and future climate data in Asia

Tongli WANG, Guangyu WANG, John L. INNES, Brad SEELY, Baozhang CHEN

《农业科学与工程前沿(英文)》 2017年 第4卷 第4期   页码 448-458 doi: 10.15302/J-FASE-2017172

摘要: While low-to-moderate resolution gridded climate data are suitable for climate-impact modeling at global and ecosystems levels, spatial analyses conducted at local scales require climate data with increased spatial accuracy. This is particularly true for research focused on the evaluation of adaptive forest management strategies. In this study, we developed an application, ClimateAP, to generate scale-free (i.e., specific to point locations) climate data for historical (1901–2015) and future (2011–2100) years and periods. ClimateAP uses the best available interpolated climate data for the reference period 1961–1990 as baseline data. It downscales the baseline data from a moderate spatial resolution to scale-free point data through dynamic local elevation adjustments. It also integrates and downscales the historical and future climate data using a delta approach. In the case of future climate data, two greenhouse gas representative concentration pathways (RCP 4.5 and 8.5) and 15 general circulation models are included to allow for the assessment of alternative climate scenarios. In addition, ClimateAP generates a large number of biologically relevant climate variables derived from primary monthly variables. The effectiveness of the local downscaling was determined based on the strength of the local linear regression for the estimate of lapse rate. The accuracy of the ClimateAP output was evaluated through comparisons of ClimateAP output against observations from 1805 weather stations in the Asia Pacific region. The local linear regression explained 70%–80% and 0%–50% of the total variation in monthly temperatures and precipitation, respectively, in most cases. ClimateAP reduced prediction error by up to 27% and 60% for monthly temperature and precipitation, respectively, relative to the original baselines data. The improvements for baseline portions of historical and future were more substantial. Applications and limitations of the software are discussed.

关键词: biologically relevant climate variables     downscaling     dynamic local regression     future climate     historical climate    

Shallow foundation response variability due to soil and model parameter uncertainty

Prishati RAYCHOWDHURY,Sumit JINDAL

《结构与土木工程前沿(英文)》 2014年 第8卷 第3期   页码 237-251 doi: 10.1007/s11709-014-0242-1

摘要: Geotechnical uncertainties may play crucial role in response prediction of a structure with substantial soil-foundation-structure-interaction (SFSI) effects. Since the behavior of a soil-foundation system may significantly alter the response of the structure supported by it, and consequently several design decisions, it is extremely important to identify and characterize the relevant parameters. Moreover, the modeling approach and the parameters required for the modeling are also critically important for the response prediction. The present work intends to investigate the effect of soil and model parameter uncertainty on the response of shallow foundation-structure systems resting on dry dense sand. The SFSI is modeled using a beam-on-nonlinear-winkler-foundation (BNWF) concept, where soil beneath the foundation is assumed to be an assembly of discrete, nonlinear elements composed of springs, dashpots and gap elements. The sensitivity of both soil and model input parameters on shallow foundation responses are investigated using first-order second-moment (FOSM) analysis and Monte Carlo simulation through Latin hypercube sampling technique. It has been observed that the degree of accuracy in predicting the responses of the shallow foundation is highly sensitive soil parameters, such as friction angle, Poisson’s ratio and shear modulus, rather than model parameters, such as stiffness intensity ratio and spring spacing; indicating the importance of proper characterization of soil parameters for reliable soil-foundation response analysis.

关键词: shallow foun dation     sensitivity analysis     centrifuge data     first-order-second-moment (FOSM) method     parameter uncertainty    

Quantification of emission variability for off-road equipment in China based on real-world measurements

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1455-x

摘要:

• Emissions from 53 in-use diesel-fueled off-road equipment were measured.

关键词: Off-road equipment     Portable emission measurement system (PEMS)     Real-world emissions     Diesel engine    

Variability of waste copper slag concrete and its effect on the seismic safety of reinforced concrete

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 117-130 doi: 10.1007/s11709-021-0788-7

摘要: Proven research output on the behavior of structures made of waste copper slag concrete can improve its utilization in the construction industry and thereby help to develop a sustainable built environment. Although numerous studies on waste copper slag concrete can be found in the published literature, no research has focused on the structural application of this type of concrete. In particular, the variability in the strength properties of waste copper slag concrete, which is required for various structural applications, such as limit state design formulation, reliability-based structural analysis, etc., has so far not attracted the attention of researchers. This paper quantifies the uncertainty associated with the compressive-, flexural- and split tensile strength of hardened concrete with different dosages of waste copper slag as fine aggregate. Best-fit probability distribution models are proposed based on statistical analyses of strength data generated from laboratory experiments. In addition, the paper presents a reliability-based seismic risk assessment of a typical waste copper slag incorporated reinforced concrete framed building, considering the proposed distribution model. The results show that waste copper slag can be safely used for seismic resistant structures as it results in an identical probability of failure and dispersion in the drift demand when compared with a conventional concrete building made of natural sand.

关键词: waste copper slag     quantification of variability     goodness-of-fit test     seismic risk assessment     PSDM    

Responding to the Paris Climate Agreement: global climate change mitigation efforts

Yong GENG, Tsuyoshi FUJITA, Anthony CHIU, Hancheng DAI, Han HAO

《能源前沿(英文)》 2018年 第12卷 第3期   页码 333-337 doi: 10.1007/s11708-018-0587-6

摘要:

关键词: valign=     top     class=     J_zhaiyao    

The most influential “Top 10 Events” in carbon neutrality and climate change in 2022

《能源前沿(英文)》 2023年 第17卷 第1期   页码 1-4 doi: 10.1007/s11708-023-0869-5

摘要: . {{custom_ra.content}} . . . {{article.highlightEn}} . . . {{article.abstractEn}} . . . {{article.authorSummayEn}} .

BUILDING CLIMATE-RESILIENT FOOD SYSTEMS IN EAST AND SOUTHEAST ASIA: VULNERABILITIES, RESPONSES AND FINANCING

《农业科学与工程前沿(英文)》 2023年 第10卷 第1期   页码 16-30 doi: 10.15302/J-FASE-2023492

摘要:

● Food systems in East and Southeast Asia are vulnerable to global warming.

关键词: food systems     climate change     East     policy     resilience and Southeast Asia    

Tackling climate change and promoting the energy revolution

Xiangwan DU

《能源前沿(英文)》 2018年 第12卷 第3期   页码 338-343 doi: 10.1007/s11708-018-0535-5

摘要:

Following the Paris Agreement, green and low-carbon development has entered into a new stage. China’s international responsibility to combat climate change is consistent with the inherent sustainable development needs of the country. In this paper, the reasonability of China’s Intended Nationally Determined Contributions (INDC) is examined and the fact that low-carbon development can lead to modernization is demonstrated based on data analysis of energy economics from developed countries. Considering the fact that such an energy revolution forms the basis for China’s low-carbon transition, a roadmap of the China’s energy utilization is presented. Based on research results from the Chinese Academy of Engineering, the three historical stages of China’s energy structure reform are analyzed. Promoting a low-carbon transition through an energy revolution is a long-term and arduous process that requires a genuine transformation of development outlook and patterns. By empirically analyzing situations at home and abroad, a conclusion is made that economic development and a low-carbon transition can be achieved simultaneously; specifically, low-carbon development fosters new points of economic growth and gives rise to different development paths.

关键词: climate change     Paris Agreement     low-carbon transition     energy revolution    

标题 作者 时间 类型 操作

Nexus security: governance, innovation and the resilient city

Michael Bruce BECK, Rodrigo VILLARROEL WALKER

期刊论文

CLIMATE-CHANGE-INDUCED TEMPORAL VARIATION IN PRECIPITATION INCREASES NITROGEN LOSSES FROM INTENSIVE CROPPING

期刊论文

Soil spatial variability impact on the behavior of a reinforced earth wall

Adam HAMROUNI, Daniel DIAS, Badreddine SBARTAI

期刊论文

Fuel variability effect on flickering frequency of diffusion flames

Jizhao LI, Yang ZHANG

期刊论文

Treatment, residual chlorine and season as factors affecting variability of trihalomethanes in small

Roberta DYCK,Geneviève COOL,Manuel RODRIGUEZ,Rehan SADIQ

期刊论文

Quantifying and mapping spatial variability of Shanghai household carbon footprints

Shangguang YANG,Chunlan WANG,Kevin LO,Mark WANG,Lin LIU

期刊论文

Distribution and temporal variability of the solar resource at a site in south-east Norway

Muyiwa S. ADARAMOLA

期刊论文

ClimateAP: an application for dynamic local downscaling of historical and future climate data in Asia

Tongli WANG, Guangyu WANG, John L. INNES, Brad SEELY, Baozhang CHEN

期刊论文

Shallow foundation response variability due to soil and model parameter uncertainty

Prishati RAYCHOWDHURY,Sumit JINDAL

期刊论文

Quantification of emission variability for off-road equipment in China based on real-world measurements

期刊论文

Variability of waste copper slag concrete and its effect on the seismic safety of reinforced concrete

期刊论文

Responding to the Paris Climate Agreement: global climate change mitigation efforts

Yong GENG, Tsuyoshi FUJITA, Anthony CHIU, Hancheng DAI, Han HAO

期刊论文

The most influential “Top 10 Events” in carbon neutrality and climate change in 2022

期刊论文

BUILDING CLIMATE-RESILIENT FOOD SYSTEMS IN EAST AND SOUTHEAST ASIA: VULNERABILITIES, RESPONSES AND FINANCING

期刊论文

Tackling climate change and promoting the energy revolution

Xiangwan DU

期刊论文