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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    

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    

Advances in eucalypt research in China

Yaojian XIE, Roger J. ARNOLD, Zhihua WU, Shuaifei CHEN, Apeng DU, Jianzhong LUO

《农业科学与工程前沿(英文)》 2017年 第4卷 第4期   页码 380-390 doi: 10.15302/J-FASE-2017171

摘要: Eucalypt plantations in China currently exceed 4.5 Mhm , and this country has the third largest area of such plantations after India and Brazil. China’s eucalypt industry now comprises a complex, multifaceted industry including seedling propagation, fertilizer production and supply, plantation silviculture, harvesting and transport, wood processing for products including lumber, pulp and paper, and wood-based panels, as well as bioenergy production and various forest byproducts and non-wood forest products. In 2015, the combined value of output of this whole industry was around 300 billion CNY. Chinese research and development (R&D) has been instrumental in supporting growth and development across the whole breadth of the country’s eucalypt industry. In this report, recent advances in this R&D are reviewed under six key topics: (1) advanced propagation technology; (2) genetic resources and breeding; (3) targeted silviculture; (4) eucalypt disease and pest management; (5) enhancing plantation ecology and sustainability; and (6) wood processing and byproduct technology. R&D has greatly facilitated expansion and proliferation of all parts of China’s eucalypt industry. This industry is now of major importance to China’s economy; it involves tens of thousands of growers and companies that provide livelihoods for hundreds of thousands of people.

关键词: China Eucalypt Research Centre     timber production     tree improvement     silviculture     forest industry     Eucalyptus    

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    

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    

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    

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    

Forest resources in China ---- Figures and Graphics

《农业科学与工程前沿(英文)》 2017年 第4卷 第4期   页码 504-508 doi: 10.15302/J-FASE-2017191

林业生态工程与血吸虫病防治

彭镇华

《中国工程科学》 2001年 第3卷 第7期   页码 12-16

摘要:

回顾了血吸虫病防治历史,分析了我国血吸虫病防治取得的成就和存在问题,提出了林业生态工程防治血吸虫病的理论,并以长江中下游血吸虫病流行滩地为研究对象,以实施抑螺防病林业生态工程,改变滩地环境因子,减少甚至消灭血吸虫病的唯一中间宿主钉螺,增加环境及经济效益为主线,对长江中下游滩地的分布,钉螺密度和钉螺分布及其与环境因子的关系,滩地植被演替方式,现有滩地植被类型的改造方式及其抑螺林农复合生态系统的结构与功能等进行了系统研究。

关键词: 林业生态工程     抑螺     滩地     长江中下游    

森林火险与气象因素的多元相关性及其分析

宋卫国,马剑,Satoh K,王健

《中国工程科学》 2006年 第8卷 第2期   页码 61-66

摘要:

森林火灾发生概率预测涉及气象、树种、地理条件与人类活动等诸因素,气象参数对火灾的影响一直是森林火灾研究的重点之一。选用日平均湿度、降水量、平均风速、平均温度和日照时间等5种典型气象参数,利用BP神经网络分析了它们对火灾发生概率的综合影响;研究了多种气象参数综合作用下火灾发生概率的变化规律。结果表明,气象参数与火灾发生概率之间存在稳定的关联,神经网络在处理多参数综合影响方面具有较好的泛化能力,可以作为预测林火概率的可靠方法,为森林火灾研究提供了基础数据。

关键词: 神经网络     森林火灾     火灾发生概率     气象参数     火灾风险    

标题 作者 时间 类型 操作

我国林产化学工业发展的新动向

宋湛谦

期刊论文

Progress of forest certification in China

Wenming LU, Maharaj MUTHOO

期刊论文

Advances in eucalypt research in China

Yaojian XIE, Roger J. ARNOLD, Zhihua WU, Shuaifei CHEN, Apeng DU, Jianzhong LUO

期刊论文

森林火灾预报的新视角

赵宪文

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

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

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

Forest resources in China ---- Figures and Graphics

期刊论文

林业生态工程与血吸虫病防治

彭镇华

期刊论文

森林火险与气象因素的多元相关性及其分析

宋卫国,马剑,Satoh K,王健

期刊论文