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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time series are nonstationary, and consequently the established methods for hydrological frequency analysis are no longer applicable.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    

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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    

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Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand in China

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

《农业科学与工程前沿（英文）》 2017年 第4卷 第1期   页码 69-80 doi: 10.15302/J-FASE-2017140

摘要： To explore the distribution of food demand and the projected trend in future food demand in China, this paper analyzed the change in current (1998–2012) per-capita demand for grain, grain-consuming and herbivorous livestock products, and predicted the food demand in 2020. The results indicated that in 1998–2012, the national per-capita consumption of grain ration declined by about 36.66%, and the per-capita consumption of grain-consu-ming and herbivorous livestock products increased by about 48% and 34.09%, respectively. The grain-consu-ming livestock products have become the primary source of both calories and protein for consumers. The proportion of herbivorous livestock products in consumer diets has increased steadily and there has been huge potential in substituting beef and mutton for pork in this dynamic market. The demand for food in different provinces of China is highly variable, which is important for planning grassland agriculture development and ensuring food safety. The demand for grain, and grain-consuming and herbivorous livestock products will increase by about 3.3%, 20% and 14% respectively by 2020. Based on the food demand and trend in the development of grassland agriculture, the 31 provinces in China are divided into three priority groups for grassland agriculture development.

关键词： arable land equivalent unit (ALEU)     food equivalent unit (FEU)     food security     grassland agriculture     time trend prediction    

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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    

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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    

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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    

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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    

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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    

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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    

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Spatial prediction of soil contamination based on machine learning: a review

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1693-1

摘要：

● A review of machine learning (ML) for spatial prediction of soil contamination.

关键词： Soil contamination     Machine learning     Prediction     Spatial distribution    

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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    

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Hybrid deep learning model for risk prediction of fracture in patients with diabetes and osteoporosis

《医学前沿（英文）》 2022年 第16卷 第3期   页码 496-506 doi: 10.1007/s11684-021-0828-7

摘要： The fracture risk of patients with diabetes is higher than those of patients without diabetes due to hyperglycemia, usage of diabetes drugs, changes in insulin levels, and excretion, and this risk begins as early as adolescence. Many factors including demographic data (such as age, height, weight, and gender), medical history (such as smoking, drinking, and menopause), and examination (such as bone mineral density, blood routine, and urine routine) may be related to bone metabolism in patients with diabetes. However, most of the existing methods are qualitative assessments and do not consider the interactions of the physiological factors of humans. In addition, the fracture risk of patients with diabetes and osteoporosis has not been further studied previously. In this paper, a hybrid model combining XGBoost with deep neural network is used to predict the fracture risk of patients with diabetes and osteoporosis, and investigate the effect of patients’ physiological factors on fracture risk. A total of 147 raw input features are considered in our model. The presented model is compared with several benchmarks based on various metrics to prove its effectiveness. Moreover, the top 18 influencing factors of fracture risks of patients with diabetes are determined.

关键词： XGBoost     deep neural network     healthcare     risk prediction    

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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    

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Position-varying surface roughness prediction method considering compensated acceleration in milling

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 855-867 doi: 10.1007/s11465-021-0649-z

摘要： Machined surface roughness will affect parts’ service performance. Thus, predicting it in the machining is important to avoid rejects. Surface roughness will be affected by system position dependent vibration even under constant parameter with certain toolpath processing in the finishing. Aiming at surface roughness prediction in the machining process, this paper proposes a position-varying surface roughness prediction method based on compensated acceleration by using regression analysis. To reduce the stochastic error of measuring the machined surface profile height, the surface area is repeatedly measured three times, and Pauta criterion is adopted to eliminate abnormal points. The actual vibration state at any processing position is obtained through the single-point monitoring acceleration compensation model. Seven acceleration features are extracted, and valley, which has the highest R-square proving the effectiveness of the filtering features, is selected as the input of the prediction model by mutual information coefficients. Finally, by comparing the measured and predicted surface roughness curves, they have the same trends, with the average error of 16.28% and the minimum error of 0.16%. Moreover, the prediction curve matches and agrees well with the actual surface state, which verifies the accuracy and reliability of the model.

关键词： surface roughness prediction     compensated acceleration     milling     thin-walled workpiece    

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Improved prediction of pile bending moment and deflection due to adjacent braced excavation

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0961-2

摘要： Deep excavations in dense urban areas have caused damage to nearby existing structures in numerous past construction cases. Proper assessment is crucial in the initial design stages. This study develops equations to predict the existing pile bending moment and deflection produced by adjacent braced excavations. Influential parameters (i.e., the excavation geometry, diaphragm wall thickness, pile geometry, strength and small-strain stiffness of the soil, and soft clay thickness) were considered and employed in the developed equations. It is practically unfeasible to obtain measurement data; hence, artificial data for the bending moment and deflection of existing piles were produced from well-calibrated numerical analyses of hypothetical cases, using the three-dimensional finite element method. The developed equations were established through a multiple linear regression analysis of the artificial data, using the transformation technique. In addition, the three-dimensional nature of the excavation work was characterized by considering the excavation corner effect, using the plane strain ratio parameter. The estimation results of the developed equations can provide satisfactory pile bending moment and deflection data and are more accurate than those found in previous studies.

关键词： pile responses     excavation     prediction     deflection     bending moments    

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标题 作者 时间 类型 操作

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

Chenglong ZHANG,Mo LI,Ping GUO

期刊论文

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

期刊论文

Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand in China

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

期刊论文

齿轮技术的创新和发展趋势

梁桂明

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

Spatial prediction of soil contamination based on machine learning: a review

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

Hybrid deep learning model for risk prediction of fracture in patients with diabetes and osteoporosis

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

Position-varying surface roughness prediction method considering compensated acceleration in milling

期刊论文

Improved prediction of pile bending moment and deflection due to adjacent braced excavation

期刊论文