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21世纪 1

人机识别;随机森林;支持向量机;逻辑回归;多维性能评价指标 1

充电模式;充电时长;随机森林;长短期记忆网络(LSTM);简化粒子群优化算法(SPSO) 1

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Effects of land use change on hydrological cycle from forest to upland field in a catchment, Japan

Chuan ZHANG, Keiji TAKASE, Hiroki OUE, Nobuhiro EBISU, Haofang YAN

《结构与土木工程前沿(英文)》 2013年 第7卷 第4期   页码 456-465 doi: 10.1007/s11709-013-0218-6

摘要: Understanding the effects of land use change on the hydrological cycle is very important for development of sustainable water resource in an upland field catchment. In this study, soil and hydrological properties in an upland field catchment, which was reclaimed partially from a forest catchment, were compared with another forest catchment. The soil properties of surface and subsurface layers were investigated in the two catchments. The soil was compacted and water-holding capacity of soil in the upland field catchment became smaller after the reclamation from forest to upland field, which decreased infiltration rate and water storage in the soil layers. We found that peak discharge and direct runoff in the upland field catchment increased compared with the forest catchment. Annual evapotranspiration from the upland field catchment tended to be lower due to the change in vegetation type and soil properties. Furthermore, a semi-distributed hydrological model was applied in the upland field catchment to understand the integrated effects of reclamation on the hydrological cycle. The model parameters, which were determined using a nonlinear optimization technique—the Shuffled Complex Evolution method (SCE), were compared between the two catchments. The Nash and Sutcliffe coefficient was used to evaluate the model performance. The simulated results indicated that evapotranspiration was decreased and change in discharge was more obvious in the surface layer. We considered that declined infiltration and water storage and increased peak discharge and direct runoff have a negative impact on water resources in the upland field catchment. This study will provide information for forest managers in planning and making decisions for land and water resource management.

关键词: land-use change     hydrological processes     upland field catchment     forest catchment     semi-distributed hydrological model    

Analysis of catchment evapotranspiration at different scales using bottom-up and top-down approaches

Xiangyu XU, Dawen YANG,

《结构与土木工程前沿(英文)》 2010年 第4卷 第1期   页码 65-77 doi: 10.1007/s11709-010-0002-9

摘要: Physically-based hydrological models are used to predict catchment water balance through detailed simulation of hydrological processes at small temporal and spatial scales. However, annual catchment water balance can also be easily and simply predicted using lumped conceptual model. Comparison between physically-based hydrological models and lumped conceptual models can help us understand the dominant factors on catchment water balance at different scales. In this paper, a distributed physically-based hydrological model (i.e., bottom-up approach) and a simple water-energy balance model (i.e., top-down approach) are used to predict actual evapotranspiration in nine sub-catchments, and the whole basin of the Luan River in northern China. Both simulations give very close values of annual evapotranspiration and show the same complementary relationship between actual and potential evapotranspiration at annual time scale. From the analysis at different time scales through comparison of the top-down and the bottom-up methods, it is shown that the annual catchment evapotranspiration is controlled mainly by annual precipitation and potential evapotranspiration, and the variability of soil water and vegetation becomes more important at a smaller time scale in the study areas. It is also known that the relationship between potential and actual evapotranspiration shows a highly nonlinear relationship at the annual and catchment scale but can be simplified to a linear relationship at hourly temporal and hillslope scales, which is commonly used in the physically-based hydrological models.

关键词: catchment evapotranspiration     distributed hydrological model     water-energy balance model     top-down and bottom-up approaches    

Analysis of rainfall runoff characteristics from a subtropical urban lawn catchment in South-east China

Jinliang HUANG, Zhenshun TU, Pengfei DU, Qingsheng LI, Jie LIN

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 531-539 doi: 10.1007/s11783-010-0287-x

摘要: Characteristics of rainfall runoff from a 3.26?hm urban catchment with predominant land-use as lawn in Xiamen City, South-east China were investigated and analyzed. Water quality and quantity measurements of rainfall runoff were conducted for ten rainfall events over the period March, 2008 to April, 2009. The results indicated that chemical oxygen demand (COD) and total phosphorus (TP) were the major pollutants with event mean concentrations of 56.09 and 0.44 mg·L . From hydrograph and pollutograph analysis of two typical rainfall events, it was clear that the peak rainfall preceded the peak flowrate by about 15–20 min. Meanwhile, concentrations of major pollutants showed multiple peaks and these peaks usually preceded peak flowrate. There were no distinctive first-flush effects except for the rainfall events with the longest rainfall duration and largest runoff volume, which was verified by the fact that the first 30% runoff volume (FF30) carried 39.36% of the total suspended solids (TSS) load, 35.17% of the COD load, 28.13% of the TP load and 39.03% of the nitrate nitrogen load. Multivariate regression analysis further demonstrated that the total runoff volume had a positive correlation with the FF30 of TSS and COD.

关键词: rainfall runoff     first flush     pollution characteristics     urban lawn catchment    

Progress of forest certification in China

Wenming LU, Maharaj MUTHOO

《农业科学与工程前沿(英文)》 2017年 第4卷 第4期   页码 414-420 doi: 10.15302/J-FASE-2017185

摘要: The Chinese Government is committed to forest certification as a market-based instrument to promote sustainable forest management. Forest certification includes a number of regulations, rules and policy paradigms related to certification and there are numerous challenges facing the uptake of forest certification in China. In particular, the ban on commercial logging in natural forests implemented by the Natural Forest Protection Program has resulted in little demand for forest certification of natural forest management units. However, there are also certification opportunities, such as the certification of non-timber forest products that benefit local communities who depend on forests for the goods and services they provide. This paper provides an overview of progress in forest certification in China, including its development history, organizational structure, scheme documents, certification scopes and standards, accreditation, certification bodies and auditors, and certification logos. The paper also focuses on government support for the supervision and management of forest certification through policy incentives, including the potential government procurement and subsidy policies for certified forest products. Finally, the paper analyzes certified non-timber forest products as an example of the value of certification to promote sustainable forest management and how the concept of forest certification can be used to add value to forests and ensure they are responsibly and sustainably managed. In general, forest certification in China has a clear role in sustainable forest management, both for timber and non-timber forest products.

关键词: China Forest Certification Scheme     forest certification     government support     opportunities and challenges     sustainable forest management    

Stormwater runoff pollution loads from an urban catchment with rainy climate in China

Liqing LI, Baoqing SHAN, Chenqing YIN

《环境科学与工程前沿(英文)》 2012年 第6卷 第5期   页码 672-677 doi: 10.1007/s11783-012-0447-2

摘要: An older urban district in Wuhan, China, is transitioning from discharging sewage and stormwater directly into lakes, to directing the sewage to wastewater treatment plants (WWTPs). Dealing with polluted stormwater discharge is a great challenge. Stormwater runoff from an urban catchment with a combined sewer system was sampled and analyzed over a three-year period. Results indicate that wet weather flows account for 66%, 31%, 17%, and 13% of the total load of suspended solids (SS), chemical oxygen demand (COD), total nitrogen, and total phosphorus, respectively. The first flush of COD and SS was significant in all runoff events. More than 50% of the SS and COD loads were transported by the first 30% of runoff volume. Storage and treatment of the first 10 mm from each combined sewer overflow event could reduce more than 70% of the annual COD overflow load. An integrated solution is recommended, consisting of a tank connected to the WWTP and a detention pond, to store and treat the combined sewer overflow (CSO). These results may be helpful in mitigating CSO pollution for many other urban areas in China and other developing countries.

关键词: combined sewer overflow     pollution load     first flush     detention basins    

森林火灾预报的新视角

赵宪文

《中国工程科学》 2000年 第2卷 第5期   页码 66-71

摘要:

从森林火灾成灾的三个基本因子(火源、环境和可燃物)入手,在宏观上对西南地区森林火灾预报方法进行了探讨。在预测林火发生方面,考虑到人为火是发生森林火灾的主要原因,有很大随机性,因而采用了马尔科夫随机过程理论。在分析成灾环境时,采用了与天、地、生相关分析的方法。特别在可燃物的贮量估测方面,用航天遥感数据,提出一套新的框算方法,为在区域的尺度上估测森林火灾给出了有效的、定量的方法,从而提高了可信度。

关键词: 森林火灾预报     航天遥感     火灾基本因子     新视角    

THE SOURCES OR SINKS OF NON-POINT SOURCE POLLUTION: OBSERVATIONS IN AN UPLAND AREA IN THE JINGLINXI CATCHMENT

《农业科学与工程前沿(英文)》 2023年 第10卷 第4期   页码 607-626 doi: 10.15302/J-FASE-2023517

摘要:

As the common features of agroecosystems, ditches and ponds benefit the irrigation and drainage, as well as intercepting non-point source pollutants. However, most ditch-pond studies have been conducted in lowland areas. To test this source-sink assumption in upland areas, this study made observations on the ecological function of the ditch and pond system in a typical catchment in China. First, the changes in ponds in the catchment were analyzed using high-resolution remote sensing data. Then, the migration of agricultural pollutants in ditches and ponds were analyzed by field sampling and laboratory detection. The results showed that over the past 15 years the length of ditches in the catchment and the number of small ponds (< 500 m2) have increased by 32% and 75%, respectively. The rate of change in nutrient concentrations in the ditches and ponds were mostly from −20% to 20%, indicating ditches and ponds can be both sources and sinks for agricultural pollutants. Lastly, the contributing factors were explored and it was found that ditches and ponds are important sinks in dry season. However, during the rainy season, ditches and ponds become sources of pollutants, with the rapid drainage of ditches and the overflow of ponds in upland areas. The results of this study revealed that the ditches and ponds could be used for ecological engineering in upland catchments to balance drainage and intercept pollutants.

关键词: ditches     ponds     non-point source pollution     mountainous areas     nitrogen     phosphorus    

我国林产化学工业发展的新动向

宋湛谦

《中国工程科学》 2001年 第3卷 第2期   页码 1-6

摘要:

林产化学工业是将可再生的森林资源经过化学加工生产出各种有用的产品。它是森林资源高效可持续利用的一个重要组成部分。文章介绍我国林产化学工业的现状,并指出今后发展方向,即加强创新研究,开发深加工产品;推进林产化工企业向大型化发展;发展木材制浆造纸和开发木质能源。

关键词: 林产化学工业     森林资源     化学加工    

Cattle manure biochar and earthworm interactively affected CO and NO emissions in agricultural and forest

《环境科学与工程前沿(英文)》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1473-8

摘要:

• Earthworms increase CO2 and N2O emissions in agricultural and forest soil.

关键词: Carbon sequestration     Forest soil     Cattle manure biochar     Greenhouse gas emissions     Soil fauna    

Floating forest: A novel breakwater-windbreak structure against wind and wave hazards

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1111-1127 doi: 10.1007/s11709-021-0757-1

摘要: A novel floating breakwater-windbreak structure (floating forest) has been designed for the protection of vulnerable coastal areas from extreme wind and wave loadings during storm conditions. The modular arch-shaped concrete structure is positioned perpendicularly to the direction of the prevailing wave and wind. The structure below the water surface acts as a porous breakwater with wave scattering capability. An array of tubular columns on the sloping deck of the breakwater act as an artificial forest-type windbreak. A feasibility study involving hydrodynamic and aerodynamic analyses has been performed, focusing on its capability in reducing wave heights and wind speeds in the lee side. The study shows that the proposed 1 km long floating forest is able to shelter a lee area that stretches up to 600 m, with 40%–60% wave energy reduction and 10%–80% peak wind speed reduction.

关键词: floating structure     breakwater     windbreak     hydrodynamic     CFD    

Dimensionality reduction and prediction of soil consolidation coefficient using random forest coupling

Hai-Bang LY; Huong-Lan Thi VU; Lanh Si HO; Binh Thai PHAM

《结构与土木工程前沿(英文)》 2022年 第16卷 第2期   页码 224-238 doi: 10.1007/s11709-022-0812-6

摘要: The consolidation coefficient of soil (Cv) is a crucial parameter used for the design of structures leaned on soft soi. In general, the Cv is determined experimentally in the laboratory. However, the experimental tests are time-consuming as well as expensive. Therefore, researchers tried several ways to determine Cv via other simple soil parameters. In this study, we developed a hybrid model of Random Forest coupling with a Relief algorithm (RF-RL) to predict the Cv of soil. To conduct this study, a database of soil parameters collected from a case study region in Vietnam was used for modeling. The performance of the proposed models was assessed via statistical indicators, namely Coefficient of determination (R2), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE). The proposal models were constructed with four sets of soil variables, including 6, 7, 8, and 13 inputs. The results revealed that all models performed well with a high performance (R2 > 0.980). Although the RF-RL model with 13 variables has the highest prediction accuracy ( R2 = 0.9869), the difference compared with other models was negligible (i.e., R2 = 0.9824, 0.9850, 0.9825 for the cases with 6, 7, 8 inputs, respectively). Thus, it can be concluded that the hybrid model of RF-RL can be employed to predict Cv based on the basic soil parameters.

关键词: soil consolidation coefficient     machine learning     random forest     Relief    

Fault diagnosis of spur gearbox based on random forest and wavelet packet decomposition

Diego CABRERA,Fernando SANCHO,René-Vinicio SÁNCHEZ,Grover ZURITA,Mariela CERRADA,Chuan LI,Rafael E. VÁSQUEZ

《机械工程前沿(英文)》 2015年 第10卷 第3期   页码 277-286 doi: 10.1007/s11465-015-0348-8

摘要:

This paper addresses the development of a random forest classifier for the multi-class fault diagnosis in spur gearboxes. The vibration signal’s condition parameters are first extracted by applying the wavelet packet decomposition with multiple mother wavelets, and the coefficients’ energy content for terminal nodes is used as the input feature for the classification problem. Then, a study through the parameters’ space to find the best values for the number of trees and the number of random features is performed. In this way, the best set of mother wavelets for the application is identified and the best features are selected through the internal ranking of the random forest classifier. The results show that the proposed method reached 98.68% in classification accuracy, and high efficiency and robustness in the models.

关键词: fault diagnosis     spur gearbox     wavelet packet decomposition     random forest    

Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

《环境科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 218-223 doi: 10.1007/s11783-008-0037-5

摘要: To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (CHN·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cm and 20–40 cm soil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (C)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.

Regional GIS-based evaluation of the potential and supply costs of forest biomass in Sweden

Dimitris ATHANASSIADIS, Tomas NORDFJELL

《农业科学与工程前沿(英文)》 2017年 第4卷 第4期   页码 493-501 doi: 10.15302/J-FASE-2017179

摘要: The potential for harvestable forest fuel (logging residues and stumps from regeneration fellings and small diameter trees from early thinnings) in Sweden, divided in five regions, is provided. Marginal cost curves for logging residues and stumps are calculated through a GIS-based method based on forest inventory plots and locations of selected terminals, and heat and combined heat and power facilities. Four supply chains for logging residues and two for stumpwood were compared. Fixed and variable costs of harvesting equipment and transport vehicles were used for determining the costs of each of the supply systems under consideration. A list with the GPS coordinates of all facilities and terminals was made based on their geographical location. The distance from the center of each forest inventory plot to the nearest receiving point within the region, either facility or terminal, was estimated. There were large differences in the estimated potential of harvestable forest fuel between the regions. The overall annual potential for each of the five regions ranged from 0.97 to 2.73 million oven dry tonnes and the total potential amounted to 9.39 Mt (oven dry). One of the northernmost regions (R1) had the steepest slope in its marginal cost curve. For the other regions, the slope of their cost curves was less dramatic. Information on the economic availability of logging residues and stumps in each region is important for forest fuel suppliers and receiving facilities.

关键词: GIS     logging residues     heat and-power faci-lities     stumpwood    

Modeling oblique load carrying capacity of batter pile groups using neural network, random forest regression

Tanvi SINGH, Mahesh PAL, V. K. ARORA

《结构与土木工程前沿(英文)》 2019年 第13卷 第3期   页码 674-685 doi: 10.1007/s11709-018-0505-3

摘要: M5 model tree, random forest regression (RF) and neural network (NN) based modelling approaches were used to predict oblique load carrying capacity of batter pile groups using 247 laboratory experiments with smooth and rough pile groups. Pile length ( ), angle of oblique load ( ), sand density ( ), number of batter piles ( ), and number of vertical piles ( ) as input and oblique load ( ) as output was used. Results suggest improved performance by RF regression for both pile groups. M5 model tree provides simple linear relation which can be used for the prediction of oblique load for field data also. Model developed using RF regression approach with smooth pile group data was found to be in good agreement for rough piles data. NN based approach was found performing equally well with both smooth and rough piles. Sensitivity analysis using all three modelling approaches suggest angle of oblique load ( ) and number of batter pile ( ) affect the oblique load capacity for both smooth and rough pile groups.

关键词: batter piles     oblique load test     neural network     M5 model tree     random forest regression     ANOVA    

标题 作者 时间 类型 操作

Effects of land use change on hydrological cycle from forest to upland field in a catchment, Japan

Chuan ZHANG, Keiji TAKASE, Hiroki OUE, Nobuhiro EBISU, Haofang YAN

期刊论文

Analysis of catchment evapotranspiration at different scales using bottom-up and top-down approaches

Xiangyu XU, Dawen YANG,

期刊论文

Analysis of rainfall runoff characteristics from a subtropical urban lawn catchment in South-east China

Jinliang HUANG, Zhenshun TU, Pengfei DU, Qingsheng LI, Jie LIN

期刊论文

Progress of forest certification in China

Wenming LU, Maharaj MUTHOO

期刊论文

Stormwater runoff pollution loads from an urban catchment with rainy climate in China

Liqing LI, Baoqing SHAN, Chenqing YIN

期刊论文

森林火灾预报的新视角

赵宪文

期刊论文

THE SOURCES OR SINKS OF NON-POINT SOURCE POLLUTION: OBSERVATIONS IN AN UPLAND AREA IN THE JINGLINXI CATCHMENT

期刊论文

我国林产化学工业发展的新动向

宋湛谦

期刊论文

Cattle manure biochar and earthworm interactively affected CO and NO emissions in agricultural and forest

期刊论文

Floating forest: A novel breakwater-windbreak structure against wind and wave hazards

期刊论文

Dimensionality reduction and prediction of soil consolidation coefficient using random forest coupling

Hai-Bang LY; Huong-Lan Thi VU; Lanh Si HO; Binh Thai PHAM

期刊论文

Fault diagnosis of spur gearbox based on random forest and wavelet packet decomposition

Diego CABRERA,Fernando SANCHO,René-Vinicio SÁNCHEZ,Grover ZURITA,Mariela CERRADA,Chuan LI,Rafael E. VÁSQUEZ

期刊论文

Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

期刊论文

Regional GIS-based evaluation of the potential and supply costs of forest biomass in Sweden

Dimitris ATHANASSIADIS, Tomas NORDFJELL

期刊论文

Modeling oblique load carrying capacity of batter pile groups using neural network, random forest regression

Tanvi SINGH, Mahesh PAL, V. K. ARORA

期刊论文