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Industrial Greening of the Dongting Lake Eco-economic Zone

Da-yuan Li,Min Huang

《工程管理前沿(英文)》 2015年 第2卷 第3期   页码 228-233 doi: 10.15302/J-FEM-2015047

摘要: Extensive industrial development is a major challenge to ecological civilization construction. Industrial energy consumption and environmental pollution reduction are desperately needed. The Dongting Lake district, located in Wuhan and the Changsha-Zhuzhou-Xiangtan (CZT) pilot zone, bears the responsibility to ensure national food security and watershed ecological security, and it is an urgent need for the Dongting Lake district to accept the ecological transition of industries. On the analysis of the industrial development status and problems of the Dongting Lake district, some proposals based on the characteristics and reality of the district are pointed out, such as industrial cooperation, proper space layout, ecological innovation, industrial structure upgrading, building of ecological parks, clean production, elimination of backward production capacity, heavy metals governance and so on, as to develop the industrial ecology of the Dongting Lake district.

关键词: industrial greening     changing patterns of development     ecological civilization     regional collaboration     the Dongting Lake Eco-economic Zone    

Exploring the development of municipal solid waste disposal facilities in Chinese cities: patterns and

《环境科学与工程前沿(英文)》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1739-4

摘要:

● We tracked Chinese cities’ MSW disposal infrastructure development history.

关键词: China     Municipal solid waste (MSW)     Landfill     Incineration     Proliferation patterns     Driving forces    

Cusp points and assembly changing motions in the PRR-PR-PRR planar parallel manipulator

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0743-x

摘要: Most parallel manipulators have multiple solutions to the direct kinematic problem. The ability to perform assembly changing motions has received the attention of a few researchers. Cusp points play an important role in the kinematic behavior. This study investigates the cusp points and assembly changing motions in a two degrees of freedom planar parallel manipulator. The direct kinematic problem of the manipulator yields a quartic polynomial equation. Each root in the equation determines the assembly configuration, and four solutions are obtained for a given set of actuated joint coordinates. By regarding the discriminant of the repeated roots of the quartic equation as an implicit function of two actuated joint coordinates, the direct kinematic singularity loci in the joint space are determined by the implicit function. Cusp points are then obtained by the intersection of a quadratic curve and a cubic curve. Two assembly changing motions by encircling different cusp points are highlighted, for each pair of solutions with the same sign of the determinants of the direct Jacobian matrices.

关键词: planar parallel manipulator     assembly changing motions     cusp points     quartic polynomial     discriminant of repeated roots    

Analysis of driving forces behind diversified carbon dioxide emission patterns in regions of the mainland

Xin TIAN, Hidefumi IMURA, Miao CHANG, Feng SHI, Hiroki TANIKAWA

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 445-458 doi: 10.1007/s11783-011-0330-6

摘要: China has large regional disparities in carbon dioxide CO emissions with economic development among its 31 provincial mainland regions. This paper investigates these disparities in CO emission patterns and identifies the factors underlying the differences. Results show that the 30 study China's mainland provinces (Tibet not included) can be divided into seven groups with three typical CO emission patterns. Index decomposition results indicate that changes in economic development, the industrial sector, and technology contribute far more to increased CO emissions than do population, energy structure, and other sectors. Close inspection reveals that different industry structures and technology contribute greatly to the differences observed in CO emissions between provinces with similar economic output. This study highlights the importance of region-specific industrial structure adjustment policies, especially for regions transitioning to heavy industry and for those still in the primary stages of industrialization. The potential application of a domestic carbon emissions trading system, to encourage regional investment in updated technology, is also discussed.

关键词: carbon dioxide emission patterns     China     economic development     index decomposition analysis     industrialization    

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

《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    

Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 279-287 doi: 10.1007/s11783-014-0667-8

摘要: A riparian ecosystem is an ecological transition zone between a river channel and terrestrial ecosystems. Riparian ecosystems play a vital role in maintaining stream health and bank stabilization. The types of riparian vegetation have changed greatly because of human activities along the Wenyu River. This study examines the impact of riparian vegetation patterns on water pollution due to soil nutrient loss. Four riparian vegetation patterns from the river channel to the upland were chosen as the focus of this study: grassland, cropland, grassland-cropland, and grassland-manmade lawn. The different distributions of soil nutrients along vegetation patterns and the potential risk of nutrient loss were observed and compared. The results showed that riparian cropland has the lowest value of total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP), and organic matter (OM), but it has the highest soil bulk density (BD). The distributions of soil TN, TP, AN, AP, and OM exhibited a declining trend from the upland toward the river channel for riparian cropland, whereas a different trend was observed for the riparian grassland. The vegetation patterns of grassland-cropland and grassland-manmade lawn show that the grassland in the lower slope has more nutrients and OM but lower soil BD than the cropland or manmade lawn in the upper slope. So, the lower-slope grassland may intercept and infiltrate surface runoff from the upland. The lower-slope grassland has higher levels of soil TN, TP, AN, and AP, and thus it may become a new source of nutrient loss. Our results suggest that the management of the riparian vegetation should be improved, particularly in densely populated areas, to control soil erosion and river pollution.

关键词: riparian     vegetation patterns     soil nutrient distribution     nutrient loss     management    

Microenvironmental time-activity patterns in Chongqing, China

Yu ZHAO, Shuxiao WANG, Gangcai CHEN, Fei WANG, Kristin AUNAN, Jiming HAO

《环境科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 200-209 doi: 10.1007/s11783-009-0010-y

摘要: An investigation using recall questionnaires was conducted in winter and autumn 2006 to evaluate the time-activity patterns in Chongqing, China. The average time spent in seven microenvironments (MEs) including outdoors, transit, living room, bedroom, kitchen, classroom/office, and other indoors were found to be about 3.5, 1.1, 2.5, 9.7, 1.4, 4.2, and 1.7 h per day, respectively. According to the results of a nonparametric test, the sampling period and day of week were significant for the variation of the time spent in all MEs except for transit and outdoors. The time budget was analyzed using a general linear model (GLM), which exhibited significant variability by demographic factors such as gender, age, residence, education, and household income.

关键词: time-activity patterns     microenvironment     general linear model (GLM)     Chongqing     China    

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence

《医学前沿(英文)》 doi: 10.1007/s11684-023-1019-5

摘要: Studies have found a U-shaped relationship between sleep duration and chronic kidney disease (CKD) risk, but limited research evaluated the association of reallocating excessive sleep to other behavior with CKD. We included 104 538 participants from the nationwide cohort of the Risk Evaluation of Cancers in Chinese Diabetic Individuals: A Longitudinal Study, with self-reported time of daily-life behavior. Using isotemporal substitution models, we found that substituting 1 h of sleeping with sitting, walking, or moderate-to-vigorous physical activity was associated with a lower CKD prevalence. Leisure-time physical activity displacement was associated with a greater prevalence reduction than occupational physical activity in working population. In stratified analysis, a lower CKD prevalence related to substitution toward physical activity was found in long sleepers. More pronounced correlations were observed in long sleepers with diabetes than in those with prediabetes, and they benefited from other behavior substitutions toward a more active way. The U-shaped association between sleep duration and CKD prevalence implied the potential effects of insufficient and excessive sleep on the kidneys, in which the pernicious link with oversleep could be reversed by time reallocation to physical activity. The divergence in the predicted effect on CKD following time reallocation to behavior of different domains and intensities and in subpopulations with diverse metabolic statuses underlined the importance of optimizing sleeping patterns and adjusting integral behavioral composition.

关键词: sleep     physical activity     chronic kidney disease     isotemporal substitution     behavioral pattern    

大型铁路建筑企业转变经营方式研究——以中铁四局为例

许宝成

《中国工程科学》 2012年 第14卷 第12期   页码 58-61

摘要:

随着国际市场后金融危机时代的来临以及国内铁路市场、房地产等行业的政策调整,以铁路为主营业务的大型建筑企业面临着很大的压力,通过分析目前建筑企业面临的困难与挑战,提出建筑企业树立先进管理理念和推进科学运营方式的必要性,并以中国中铁四局集团有限公司为例研究铁路建筑企业转变经营方式的方向、路径和措施。

关键词: 建筑企业     铁路     转型     经营方式    

Assessment of bridge expansion joints using long-term displacement measurement under changing environmental

Youliang DING, Aiqun LI

《结构与土木工程前沿(英文)》 2011年 第5卷 第3期   页码 374-380 doi: 10.1007/s11709-011-0122-x

摘要: This paper addresses the problem of condition assessment of bridge expansion joints using long-term measurement data under changing environmental conditions. The effects of temperature, traffic loading and wind on the expansion joint displacements are analyzed and interpreted, which reveal that measured displacements are observed to increase with an increase in temperature and to decrease with increased traffic loading, while the correlation between displacement and wind speed is very weak. Two regression models are developed to simulate the varying displacements under the changes in temperature and traffic loadings. Based on these models, the effects of the environmental conditions are removed to obtain the normalized displacement. Statistical process control using mean value control charts is further used to detect damage to the bridge expansion joints. The results reveal that the proposed method had a good capability for detecting the damage-induced 1.0% variances of the annual changes in the expansion joint displacements.

关键词: structural health monitoring     displacement     expansion joint     temperature effect     wind effect     traffic loading     statistical process control     suspension bridge    

Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

《医学前沿(英文)》 doi: 10.1007/s11684-023-1023-9

摘要: Malnutrition in early life increases the risk of osteoporosis, but the association of early-life undernutrition combined with adulthood obesity patterns with low-energy fracture remains unknown. This study included 5323 community-dwelling subjects aged ≥40 years from China. Early-life famine exposure was identified based on the participants’ birth dates. General obesity was assessed using the body mass index (BMI), and abdominal obesity was evaluated with the waist-to-hip ratio (WHR). Low-energy fracture was defined as fracture occurring after the age of 40 typically caused by falls from standing height or lower. Compared to the nonexposed group, the group with fetal, childhood, and adolescence famine exposure was associated with an increased risk of fracture in women with odds ratios (ORs) and 95% confidence intervals (CIs) of 3.55 (1.57–8.05), 3.90 (1.57–9.71), and 3.53 (1.05–11.88), respectively, but not in men. Significant interactions were observed between fetal famine exposure and general obesity with fracture among women (P for interaction = 0.0008). Furthermore, compared with the groups with normal BMI and WHR, the group of women who underwent fetal famine exposure and had both general and abdominal obesity had the highest risk of fracture (OR, 95% CI: 3.32, 1.17–9.40). These results indicate that early-life famine exposure interacts with adulthood general obesity and significantly increases the risk of low-energy fracture later in life in women.

关键词: famine     obesity     body mass index     waist-to-hip ratio     low-energy fracture    

Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source

Yilan Cui, Xing Xie, Yi Liu

《环境科学与工程前沿(英文)》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1068-1

摘要:

Check-in and survey data are explored to identify personal activity-specific places.

Ways for detecting and moderating sample bias of Weibo check-in data is proposed.

A graphic representation of urban activity intensity in Beijing, China is presented.

The potential application of Weibo check-in data for urban analysis is introduced.

关键词: Social media     Human mobility     Population bias     Sample reconstruction     Data integration    

Clinical efficacy of comprehensive therapy based on traditional Chinese medicine patterns on patients

《医学前沿(英文)》 2022年 第16卷 第5期   页码 736-744 doi: 10.1007/s11684-021-0870-5

摘要: Effective therapy options for pneumoconiosis are lacking. Traditional Chinese medicine (TCM) presents a favorable prospect in the treatment of pneumoconiosis. A pilot study on TCM syndrome differentiation can evaluate the clinical efficacy and safety of TCM and lay a foundation for further clinical research. A double-blind, randomized, and placebo-controlled trial was conducted for 24 weeks, in which 96 patients with pneumoconiosis were randomly divided into the control and treatment groups. Symptomatic treatment was conducted for the two groups. The treatment group was treated with TCM syndrome differentiation, and the control group was treated with placebo. The primary outcomes were the six-minute walking distance (6MWD) and the St. George Respiratory Questionnaire (SGRQ) score. The secondary outcomes were the modified British Medical Research Council Dyspnea Scale (mMRC), Chronic Obstructive Pulmonary Disease Assessment Test (CAT), Hospital Anxiety and Depression Scale (HADS), and pulmonary function. Only 83 patients from the 96 patients with pneumoconiosis finished the study. For the primary outcome, compared with the control groups, the treatment group showed a significantly increased 6MWD (407.90 m vs. 499.51 m; 95% confidence interval (CI) 47.25 to 135.97; P <0.001) and improved SGRQ total score (44.48 vs. 25.67; 95% CI −27.87 to −9.74; P <0.001). The treatment group also significantly improved compared with the control group on mMRC score (1.4 vs. 0.74; 95% CI −1.08 to −0.23; P =0.003), CAT score (18.40 vs. 14.65; 95% CI −7.07 to −0.43; P =0.027), and the total symptom score (7.90 vs. 5.14; 95% CI −4.40 to −1.12; P <0.001). No serious adverse events occurred. This study showed that TCM syndrome differentiation and treatment had a favorable impact on the exercise endurance and quality of life of patients with pneumoconiosis.

关键词: pneumoconiosis     randomized controlled trials     traditional Chinese medicine    

以喂养方式视角浅析新时期城市基层计生优质服务

严小青

《中国工程科学》 2014年 第16卷 第5期   页码 24-30

摘要:

通过选取杭州市上城区社区卫生院109 例婴儿及其母亲为调查对象,利用SPSS18.0 软件分别从一般参考量、影响喂养方式相关性因素以及基层计生优质服务需求进行数据统计分析,从而得到影响母乳喂养因素、喂养方式与婴儿体格关系以及服务需求重点,从而提出要从卫生计生联手、育医结合,立足基层架构群众满意服务网络;探索途径、优化服务,实现流动人口优质服务一盘棋;强化队伍、创新机制,探索建立科学规范服务考核评估体系三方面全面提升新时期基层计生优质服务水平。

关键词: 喂养方式     统计分析     计生优质服务    

contributions of friction and plastic deformation to machined surface temperatures and residual stress patterns

Subhash ANURAG, Yuebin GUO,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 247-255 doi: 10.1007/s11465-010-0097-7

摘要: Temperature on the machined surface is critical for surface integrity and the performance of a precision component. However, the temperature of a machined surface is challenging for in-situ measurement. Furthermore, the individual contribution of tool/work friction and plastic deformation of work materials to surface temperature is very difficult to quantify because the measured temperature is always the resultant temperature. This lack of understanding on the temperature distribution blocks the design of effective cutting tool geometries and materials to minimize surface temperature. This study provides a finite element method based on a predictive model to decouple the contributions of tool/work friction and material plastic deformation to surface temperature in a dry cutting process. The study shows that the plastic deformation of work material contributes to the majority of surface temperature, whereas the tool/work friction contribution is secondary. High temperatures are produced when more materials are plowed under the cutting edge. A large tool/work friction leads to higher surface temperatures, and the use of a cutting tool with physical properties in process simulation significantly improves the accuracy of predicted surface temperatures. Residual stress reversal from subsurface maximum residual to surface maximum residual stress may occur when tool/work friction increases.

关键词: surface temperature     friction     residual stress     finite element analysis (FEA)     dry cutting     tool property    

标题 作者 时间 类型 操作

Industrial Greening of the Dongting Lake Eco-economic Zone

Da-yuan Li,Min Huang

期刊论文

Exploring the development of municipal solid waste disposal facilities in Chinese cities: patterns and

期刊论文

Cusp points and assembly changing motions in the PRR-PR-PRR planar parallel manipulator

期刊论文

Analysis of driving forces behind diversified carbon dioxide emission patterns in regions of the mainland

Xin TIAN, Hidefumi IMURA, Miao CHANG, Feng SHI, Hiroki TANIKAWA

期刊论文

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

期刊论文

Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

期刊论文

Microenvironmental time-activity patterns in Chongqing, China

Yu ZHAO, Shuxiao WANG, Gangcai CHEN, Fei WANG, Kristin AUNAN, Jiming HAO

期刊论文

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence

期刊论文

大型铁路建筑企业转变经营方式研究——以中铁四局为例

许宝成

期刊论文

Assessment of bridge expansion joints using long-term displacement measurement under changing environmental

Youliang DING, Aiqun LI

期刊论文

Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

期刊论文

Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source

Yilan Cui, Xing Xie, Yi Liu

期刊论文

Clinical efficacy of comprehensive therapy based on traditional Chinese medicine patterns on patients

期刊论文

以喂养方式视角浅析新时期城市基层计生优质服务

严小青

期刊论文

contributions of friction and plastic deformation to machined surface temperatures and residual stress patterns

Subhash ANURAG, Yuebin GUO,

期刊论文