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Space view of the decadal variation for typical air pollutants in the Pearl River Delta (PRD) region

Zifeng WANG, Min SHAO, Liangfu CHEN, Minghui TAO, Liuju ZHONG, Duohong CHEN, Meng FAN, Yang WANG, Xinhui WANG

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0853-y

摘要: Spatial and temporal trends of the typical pollutants in PRD viewed from space. Comparisons of the satellite retrievals with the collocated in situ data are given. Among different MCs, the control measures applied in PRD are the most effective. The unique HCHO trends imply significant contribution from the biogenic origins. The Pearl River Delta (PRD) is one of the most industrialized, urbanized and populated regions in China, and thus has been long suffering from severe air pollutions. Space data provide a unique perspective for investigating the atmospheric environment at a regional scale. By utilizing multiple satellite retrievals from 2005 to 2013, this study presented, for the first time, the spatial patterns and temporal trends of typical air pollutants over PRD and its vicinity. As viewed from space, aerosol optical depth (AOD), NO2 and SO2 all had their higher values at the central part of PRD, and showed clear descending gradients as moving to the outskirt of this region. As to the inter-annual variation, all these pollutants had decreasing trends in PRD during the study period, which generally agreed with the relevant in situ measurements. However, the satellite retrievals differed from ground measurements when addressing NO2 and SO2 in the vicinity of PRD. This work also provides the inter-comparison among PRD and three other metropolitan clusters in China: PRD had relatively high AOD, moderate NO2 and low SO2 levels, and it was the only region achieving the effective reduction of NO2 and SO2 during last decade. Unlike the previous three pollutants, HCHO observed by satellite showed very special patterns: it had a relatively homogeneous spatial distribution over both of PRD and its vicinity, and presented an opposite increasing trend from 2005 to 2010. Moreover, PRD had the highest HCHO level among all the metropolitan clusters, hinting a considerable contribution of biogenic origins of HCHO in PRD.

关键词: The Pearl River Delta (PRD)     Satellite monitoring     Regional air quality     Long-term trend     HCHO    

Evaluation of the influence of El Niño–Southern Oscillation on air quality in southern China from long-term historical observations

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1460-0

摘要:

•Strong ENSO influence on AOD is found in southern China region.

关键词: El Niño–Southern Oscillation     Aerosol concentration     Aerosol particle size     Contribution separation     Decadal trend     Southern China    

齿轮技术的创新和发展趋势

梁桂明

《中国工程科学》 2000年 第2卷 第3期   页码 1-6

摘要:

最早的齿轮是怎样发明出来的?它源于何方?用于何处?——这是近百年来人们在探索的一个谜。 两千年前,在中国、印度、希腊、罗马、埃及出土和出水的铸铁齿轮与青铜齿轮似乎解开了这个谜。其实不然, 它们只是第2代齿轮。第1代齿轮是木制齿轮。它源于四千年前,各文明古国发明水力机械中伴生。这是由于 这些文明古国聚居大河与海湾,与水有“缘分”所致。第2代齿轮的辉煌点表现在公元前200年中国的发明 ——指南车上。它在世界上第一次发明了差动机构,第一次实现半自动控制机构,第一次出现有走向功能的机 器人。1800年工业革命带来了第3代齿轮,其特征是用直刃刀具成批生产渐开线的钢制齿轮形成了现代齿轮的 技术平台。进人21世纪,以高强度复合材料代替资源匮乏的钢材,标志着新一代(第4代)齿轮的到来,它将 与知识经济共存。未来50年齿轮创新的趋势,是追求小化、净化、静化,高可靠性、高强度、高转速和低材 耗、低能耗、低重量。

关键词: 齿轮     创新     发展趋势    

Trend detection and stochastic simulation prediction of streamflow at Yingluoxia hydrological station

Chenglong ZHANG,Mo LI,Ping GUO

《农业科学与工程前沿(英文)》 2017年 第4卷 第1期   页码 81-96 doi: 10.15302/J-FASE-2016112

摘要: Investigating long-term variation and prediction of streamflow are critical to regional water resource management and planning. Under the continuous influence of climate change and human activity, the trends of hydrologic time series are nonstationary, and consequently the established methods for hydrological frequency analysis are no longer applicable. Five methods, including the linear regression, nonlinear regression, change point analysis, wavelet analysis and Hilbert-Huang transformation, were first selected to detect and identify the deterministic and stochastic components of streamflow. The results indicated there was a significant long-term increasing trend. To test the applicability of these five methods, a comprehensive weighted index was then used to assess their performance. This index showed that the linear regression was the best method. Secondly, using the normality test for stochastic components separated by the linear regression method, a normal distribution requirement was satisfied. Next, the Monte Carlo stochastic simulation technique was used to simulate these stochastic components with normal distribution, and thus a new ensemble hydrological time series was obtained by combining the corresponding deterministic components. Finally, according to these outcomes, the streamflow at different frequencies in 2020 was predicted.

关键词: Monte Carlo     nonstationary     trend detection     streamflow prediction     decomposition and ensemble     Yingluoxia    

Temporal trend of mortality from major cancers in Xuanwei, China

null

《医学前沿(英文)》 2015年 第9卷 第4期   页码 487-495 doi: 10.1007/s11684-015-0413-z

摘要:

Although a number of studies have examined the etiology of lung cancer in Xuanwei County, China, other types of cancer in this county have not been reported systematically. This study aimed to investigate the temporal trend of eight major cancers in Xuanwei County using data from three mortality surveys (1973–1975, 1990–1992, and 2004–2005). The Chinese population in 1990 was used as a standard population to calculate age-standardized mortality rates. Cancers of lung, liver, breast, brain, esophagus, leukemia, rectum, and stomach were identified as the leading cancers in this county in terms of mortality rate. During the three time periods, lung cancer remained as the most common type of cancer. The mortality rates for all other types of cancer were lower than those of the national average, but an increasing trend was observed for all the cancers, particularly from 1990–1992 to 2004–2005. The temporal trend could be partly explained by changes in risk factors, but it also may be due to the improvement in cancer diagnosis and screening. Further epidemiological studies are warranted to systematically examine the underlying reasons for the temporal trend of the major cancers in Xuanwei County.

关键词: cancer     mortality     Xuanwei     temporal trend    

Detection of critical road roughness sections by trend analysis and investigation of driver speed interaction

Meltem SAPLIOGLU; Ayse UNAL; Melek BOCEK

《结构与土木工程前沿(英文)》 2022年 第16卷 第4期   页码 515-532 doi: 10.1007/s11709-022-0814-4

摘要: Pavement roughness (IRI—International Roughness Index values) influence the stability of traffic movements both on intercity roads and urban roads. This study is to determine the exact locations of critical pavement roughness values that affect traffic motion stability and comfort in city centre highway arteries. Roughness data with 10 m intervals were collected on a 3140 m divided road containing three consecutive signalized intersections in the city centre arterial. These data were analysed using the distance-dependent Mann-Kendall trend analysis method and checkerboard model. The sections where roughness is important were determined at a 95% confidence interval. The results will show where future pavement improvements should be prioritized for municipalities and road maintenance engineers and will form a basis for the urban road management system.

关键词: trend analysis     checkerboard model     IRI     driver speed    

Atomic and close-to-atomic scale manufacturing—A trend in manufacturing development

Fengzhou FANG

《机械工程前沿(英文)》 2016年 第11卷 第4期   页码 325-327 doi: 10.1007/s11465-016-0402-1

摘要:

Manufacturing is the foundation of a nation’s economy. It is the primary industry to promote economic and social development. To accelerate and upgrade China’s manufacturing sector from “precision manufacturing” to “high-performance and high-quality manufacturing”, a new breakthrough should be found in terms of achieving a “leap-frog development”. Unlike conventional manufacturing, the fundamental theory of “Manufacturing 3.0” is beyond the scope of conventional theory; rather, it is based on new principles and theories at the atomic and/or close-to-atomic scale. Obtaining a dominant role at the international level is a strategic move for China’s progress.

关键词: atomic manufacturing     Manufacturing 3.0     Manufacturing 2025     Industry 4.0    

Innovation-driven trend shaping COVID-19 vaccine development in China

《医学前沿(英文)》 doi: 10.1007/s11684-023-1034-6

摘要: Confronted with the coronavirus disease 2019 (COVID-19) pandemic, China has become an asset in tackling the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission and mutation, with several innovative platforms, which provides various technical means in this persisting combat. Derived from collaborated researches, vaccines based on the spike protein of SARS-CoV-2 or inactivated whole virus are a cornerstone of the public health response to COVID-19. Herein, we outline representative vaccines in multiple routes, while the merits and plights of the existing vaccine strategies are also summarized. Likewise, new technologies may provide more potent or broader immunity and will contribute to fight against hypermutated SARS-CoV-2 variants. All in all, with the ultimate aim of delivering robust and durable protection that is resilient to emerging infectious disease, alongside the traditional routes, the discovery of innovative approach to developing effective vaccines based on virus properties remains our top priority.

关键词: SARS-CoV-2     COVID-19 vaccine     vaccine development    

研发全球化是经济全球化的新趋势

张彦仲

《中国工程科学》 2005年 第7卷 第9期   页码 14-17

摘要:

分析了经济全球化对世界发展产生的重大影响,提出研发全球化是经济全球化的一个新阶段;研究了研发全球化的机遇与挑战及对经济全球化的促进和影响;分析了跨国公司在中国设立研发机构的特点;提出了鼓励在发展中国家建立研发机构的措施及发展中国家应采取的对策。

关键词: 研发全球化     经济全球化     跨国公司     研发中心     新趋势    

The development trend and practical innovation of smart cities under the integration of new technologies

Xiaohong CHEN

《工程管理前沿(英文)》 2019年 第6卷 第4期   页码 485-502 doi: 10.1007/s42524-019-0057-9

摘要: Smart cities have rapidly developed in the context of the integration of new digital technologies such as big data, Internet of Things, artificial intelligence, blockchains, and virtual reality. These cities have conducted practical innovations and typical cases in many sectors, such as in government, transportation, environmental protection, energy, medical care, and logistics, and have produced many social, economic, and ecological benefits. However, there are still some problems that continue to hinder the construction of smart cities. This paper examines such problems in depth and proposes some relevant countermeasures and suggestions.

关键词: new technology integration     smart city     big data     practical innovation    

水利水电地下工程技术现状、发展方向及创新前沿研究

马洪琪

《中国工程科学》 2011年 第13卷 第12期   页码 15-19

摘要:

介绍了我国地下工程技术取得的主要成就。面对城市化进程加快、资源短缺、环境恶化和土地衰退的严峻挑战,地下空间将成为新型国土资源加以开发利用,地下工程需求潜力巨大。提出了今后地下工程技术创新前沿研究的基础科学和关键技术问题。

关键词: 地下工程技术     现状及发展方向     创新前沿研究    

论主战坦克技术特点和发展趋势

王哲荣

《中国工程科学》 2002年 第4卷 第11期   页码 7-11

摘要:

阐述了坦克在战争中的地位,及其将光、机、电、液技术集成为复杂的武器系统,具有强大火力、高度机动与综合防护于一身的性能特点。在分析当前主战坦克存在问题和发展动态的基础上,为适应未来高新技术条件下的作战要求,综述了下一代主战坦克应向低矮化、轻量化、数字化、隐身化的方向发展。

关键词: 主战坦克     技术特点     发展趋势    

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

《机械工程前沿(英文)》 2010年 第5卷 第2期   页码 171-175 doi: 10.1007/s11465-009-0091-0

摘要: Trend prediction technology is the key technology to achieve condition-based maintenance of mechanical equipment. Large-sized water injection units are key equipment in oilfields. The traditional preventive maintenance is not economical and cannot completely avoid vicious accidents. To ensure the normal operation of units and save maintenance costs, trend prediction technology is studied to achieve condition-based maintenance for water injection units. The main methods of the technology are given, the trend prediction method based on neural network is put forward, and the expert system based on the knowledge is developed. The industrial site verification shows that the proposed trend prediction technology can reflect the operating condition trend change of the water injection units and provide technical means to achieve condition-based predictive maintenance.

关键词: water injection units     condition-based maintenance     trend prediction    

Development trend of urban design in “digital age”: Pan-dimensionality and individual-ubiquity

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 569-575 doi: 10.1007/s11709-021-0735-7

摘要: The wave of “digital age” featuring digital information is coming. Digital technology is profoundly changing the societal development direction and evolution paths. It also has significant bearing on production modes, social interactions and lifestyles. With regard to urban design, a system of knowledge about the creation and adaptation of material space forms that integrate humanities, art, technology and materials, digital technology has provided it with a brand-new and revolutionary scientific impetus for its evolution. The result of this evolution is “digital urban design paradigm based on human-computer interaction”, i.e., the urban development is moving toward “pan-dimensionality” and “individual ubiquity”. The future of urban design will construct a new approach to urban research and engineering, which is more complex, capable of accommodating and compatible with multiple goals of “instrumental rationality” and “value rationality”. Such a new approach shall be led by the probabilistic theory of “gray scale thinking”, reflecting quaternary synergetic view of “scientific rationality, ecological rationality, cultural rationality and technical rationality” to realize the cognitive progress of “engineering for the benefit of mankind”.

关键词: digital age     urban design     multiple objectives     human-computer interaction     pan-dimensionality     individual-ubiquity    

论地对空雷达干扰系统在局部战争中的作用及其发展

张锡祥

《中国工程科学》 2000年 第2卷 第7期   页码 55-65

摘要:

文章介绍了从地对空干扰机的发展概况,从单一干扰轰炸瞄准雷达,发展成地对空干扰系统和系列,可以干扰空载作战飞机雷达、导弹制导雷达、精密制导雷达、预警机雷达、星载探测雷达等,分析了这些雷达的干扰原理、干扰方法和干扰机的布局。文章对新体制雷达的干扰压制系数进行了分析,导出各类新体制雷达的干扰压制系数表达式,并提供了计算机仿真和实际试验的结果。文章分析了90年代以来两次现代化局部战争,地对空干扰系统若能发挥作用,将使被入侵国家的损失率下降,使入侵者的损失率升高。地对空干扰系统具有攻防兼备的立体干扰系列功能,需要经费较低,很适合于第三世界国家的需求,具有广泛的发展前景。

关键词: 地对空干扰系统     在现代化战争中作用     发展前景    

标题 作者 时间 类型 操作

Space view of the decadal variation for typical air pollutants in the Pearl River Delta (PRD) region

Zifeng WANG, Min SHAO, Liangfu CHEN, Minghui TAO, Liuju ZHONG, Duohong CHEN, Meng FAN, Yang WANG, Xinhui WANG

期刊论文

Evaluation of the influence of El Niño–Southern Oscillation on air quality in southern China from long-term historical observations

期刊论文

齿轮技术的创新和发展趋势

梁桂明

期刊论文

Trend detection and stochastic simulation prediction of streamflow at Yingluoxia hydrological station

Chenglong ZHANG,Mo LI,Ping GUO

期刊论文

Temporal trend of mortality from major cancers in Xuanwei, China

null

期刊论文

Detection of critical road roughness sections by trend analysis and investigation of driver speed interaction

Meltem SAPLIOGLU; Ayse UNAL; Melek BOCEK

期刊论文

Atomic and close-to-atomic scale manufacturing—A trend in manufacturing development

Fengzhou FANG

期刊论文

Innovation-driven trend shaping COVID-19 vaccine development in China

期刊论文

研发全球化是经济全球化的新趋势

张彦仲

期刊论文

The development trend and practical innovation of smart cities under the integration of new technologies

Xiaohong CHEN

期刊论文

水利水电地下工程技术现状、发展方向及创新前沿研究

马洪琪

期刊论文

论主战坦克技术特点和发展趋势

王哲荣

期刊论文

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

期刊论文

Development trend of urban design in “digital age”: Pan-dimensionality and individual-ubiquity

期刊论文

论地对空雷达干扰系统在局部战争中的作用及其发展

张锡祥

期刊论文