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适应新常态 保持严管态 确保工程质量和安全形势稳定好转 被引量:1
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《建筑监督检测与造价》 2015年第2期2-3,共2页
陈天翼总工程师在全省房屋市政工程质量安全管理工作会议讲话摘要3月12日,省住房城乡建设厅在广州召开了2015年全省房市政工程质量安全管理暨上半年防范较大及以上建筑施工生产安全事故工作会议。省住房城乡建设厅党组成员、总工程师陈... 陈天翼总工程师在全省房屋市政工程质量安全管理工作会议讲话摘要3月12日,省住房城乡建设厅在广州召开了2015年全省房市政工程质量安全管理暨上半年防范较大及以上建筑施工生产安全事故工作会议。省住房城乡建设厅党组成员、总工程师陈天翼出席会议并作重要讲话,分析总结我省2014年全省房屋市政工程质量安全工作,对2015年工程质量安全工作做出部署和要求。全省各地级以上市住房和城乡建设局(委)。 展开更多
关键词 工程质量 城乡建设厅 管态 讲话摘要 建筑施工 施工安全监督 佛山市顺德区 建筑市场诚信 建筑业协会
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Constructing Marine Ecological Civilization of Qingdao 被引量:3
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作者 孙云潭 于晓 《Marine Science Bulletin》 CAS 2010年第1期89-96,共8页
Ocean is a distinctive and prior resource in Qingdao. This paper makes summary and analysis of the practice of constructing marine ecological civilization in Qingdao and offers suggestions for the future development o... Ocean is a distinctive and prior resource in Qingdao. This paper makes summary and analysis of the practice of constructing marine ecological civilization in Qingdao and offers suggestions for the future development of the city. With the implementation of the city's strategy of =Protecting the bay and developing the city on the bay", the suggestions focus on between management & utilization, so as to establish the harmony between the optimal utilization of madne resource and marine ecological environment protection, and to consistently promote marine ecological civilization 展开更多
关键词 marine management ecological civilization suggestions
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EXPERIMENTAL INVESTIGATION ON FLOW AND HEAT TRANSFER CHARACTERISTICS IN TENON JOINT GAP BETWEEN TURBINE BLADE AND DISK 被引量:2
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作者 常海萍 黄太平 陈万兵 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期52-56,共5页
The now and heat transfer characteristics in tenon joint gap between turbine blade and disk have been investigated experimentally with a scale up model. The characteristics of flow and heat transfer in this speCial ga... The now and heat transfer characteristics in tenon joint gap between turbine blade and disk have been investigated experimentally with a scale up model. The characteristics of flow and heat transfer in this speCial gap passage have been analyzed. The results are useful for beat transfer analysis in turbine design. 展开更多
关键词 flow heat transfer non-circular tube transition multistate flow
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DRX rules during extrusion process of large-scale thick-walled Inconel 625 pipe by FE method 被引量:4
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作者 党利 杨合 +3 位作者 郭良刚 石磊 张君 郑文达 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期3037-3047,共11页
A thermal-mechanical and micro-macro coupled finite element(FE) model for the hot extrusion process of large-scale thick-walled Inconel 625 pipe was developed based on the DEFORM-2D platform.Then,the influence rules... A thermal-mechanical and micro-macro coupled finite element(FE) model for the hot extrusion process of large-scale thick-walled Inconel 625 pipe was developed based on the DEFORM-2D platform.Then,the influence rules of the key extrusion parameters on the average grain size and grain uniformity of the extruded pipe were revealed.The results show that with the increase of initial billet temperature,extrusion speed and friction coefficient,the grain uniformity is firstly improved and then deteriorated.Larger extrusion ratio leads to more uniform grain distribution.With the increase of initial billet temperature,the average grain size of the pipe first decreases and then increases.Additionally,larger extrusion ratio can bring smaller average grain size.The extrusion speed and friction coefficient have slight effects on the average grain size of the extruded pipe. 展开更多
关键词 Inconel 625 alloy large-scale thick-walled pipe extrusion dynamic recrystallization grain size grain uniformity
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Application of Dynamic Programming Method in Optimization of Water Distribution Pipe Network 被引量:2
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作者 樊鹏 王莹 +1 位作者 杨建波 杨青伟 《Agricultural Science & Technology》 CAS 2014年第4期703-705,共3页
With a water-supply network by dynamic programming. The minimal as an example, the network was optimized annual discounted costs were taken as an objective function and node pressure etc. as constraint conditions. The... With a water-supply network by dynamic programming. The minimal as an example, the network was optimized annual discounted costs were taken as an objective function and node pressure etc. as constraint conditions. The alternative pipe diameters were optimized as per enumeration method and the group allowing objective function with the least values would be the optimized one. It is proved the optimized pipe network reduced by 11.49% in terms of cost and the optimized ben- efits proved much significant. 展开更多
关键词 DYNAMICPROGRAMMING Water distribution pipe network OPTIMIZATION
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Rocky Desertification Dynamic Analysis and the Development of Management Information System 被引量:12
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作者 颜学莉 谢世友 《Agricultural Science & Technology》 CAS 2008年第2期45-48,92,共5页
With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was... With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was designed according to the natural and humane characteristics in Nanchuan of Sichuan Province. The system was composed of data management module, information query module for rocky desertification, spatial analysis module and dynamic monitoring module. 展开更多
关键词 Rocky desertification Inforumtion system Dynamic analysis Nanchuan
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Study on Bio-Ecology of the Spider Clubiona corrugate
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作者 李秦晋 王娟 +2 位作者 严真真 赵丽 王智 《Agricultural Science & Technology》 CAS 2015年第6期1243-1246,共4页
Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered w... Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered with spiderlings, adults and instars turn into adults after 6-8 molts. It had 2-3 generations each year in Hunan, and it owned the character of overlapping of generation in paddies. The average duration of generations of C. corrugate was 158.2 days, and the survival days av-eraged 223.2 days. The female and male mated several times without cannibalistic behavior, average number of eggs female laid throughout its adult life was 371.5, and hatchability can get 85.4%. The sex ratio was 1∶1. Its capability of resistance to starvation and drought was strong. Through indoor observation, the spider can sur-vive 25-61 days under the condition of no water and food. [Conclusion] The behav-ior of C. corrugate was also recorded in detail, and female usual y has a strong a-bility to protect their egg-sacs and spiderlings. At present, the bio-ecology and be-havior of the spider C. corrugate had not been reported. 展开更多
关键词 Clubiona corrugate BIOLOGY ECOLOGY SPIDER
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First-principles Study of Field Emissions from Natrium-Encapsulated Boron-Nitride Nanotube in a Perpendicular Geometry
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作者 高强 胡双林 李斌 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期553-557,621,共6页
The field emission from pure boron-nitride nanotube and boron-nitride nanotube encapsu- lated with natrium atoms with the electric field perpendicular to the axis of nanotubes is simulated based on a self-consistent m... The field emission from pure boron-nitride nanotube and boron-nitride nanotube encapsu- lated with natrium atoms with the electric field perpendicular to the axis of nanotubes is simulated based on a self-consistent method using the density-functional formalism. It has been found that the nearly-free-electron states in boron-nitride nanotube would perform very well in field emissions after natrium atom encapsulation. The characters of total energy distribution curves are analyzed to seek the function of nearly-free-electron states in the field emission, with special attention to response of the emission current to the external electric field. At last, the perpendicular emission geometry is found to possess a very sensitive response degree which is supposed to be related to specific expansion orientation of the nearly-free-electron states in this system. 展开更多
关键词 Field emission Boron-nitride nanotube Nearly-free-electron state Response
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《湖北省森林采伐管理办法》开始施行
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作者 王润章 《绿色大世界》 1996年第2期8-8,共1页
湖北省又一部重要的地方性林业法规《湖北省森林采伐管理办法》,1995年11月30日经省八届人大常委会第17次会议审议通过,已于1996年1月1日在全省正式施行。
关键词 八届人大 林业法规 日经 森林采伐限额 管理办法 管态 月将 目标管理
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A Self-organization Mapping Neural Network Algorithm and Its Application to Identify Ecosystem Service Zones 被引量:16
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作者 战金艳 史娜娜 +1 位作者 吴红 邓祥征 《Agricultural Science & Technology》 CAS 2009年第5期162-165,共4页
The self-organization mapping (SOM) neural network algorithm is a new method used to identify the ecosystem service zones at regional extent. According to the ecosystem assessment framework of Millennium Ecosystem A... The self-organization mapping (SOM) neural network algorithm is a new method used to identify the ecosystem service zones at regional extent. According to the ecosystem assessment framework of Millennium Ecosystem Assessment ( MA), this paper develops an indicator system and conducts a spatial cluster analysis at the 1km by I km grid pixel scale with the SOM neural network algorithm to sort the core ecosystem services over the vertical and horizontal dimensions. A case study was carried out in Xilingol League. The ecosystem services in Xilingol League could be divided to six different ecological zones. The SOM neural network algorithm was capable of identifying the similarities among the input data automatically. The research provides both spatially and temporally valuable information targeted sustainable ecosystem management for decision-makers. 展开更多
关键词 Neural network algorithm Ecosystem services Ecosystem service zones Sustainable ecosystem management
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Simulation of temperature field and metal flow during continuous semisolid extending extrusion process of 6201 alloy tube 被引量:3
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作者 管仁国 赵占勇 +2 位作者 钞润泽 连超 温景林 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1182-1189,共8页
A continuous semisolid extending extrusion (CSEP) method was proposed. Temperature field and metal flow during continuous semisolid extending extrusion process of 6201 alloy tube were studied. During the process, th... A continuous semisolid extending extrusion (CSEP) method was proposed. Temperature field and metal flow during continuous semisolid extending extrusion process of 6201 alloy tube were studied. During the process, the temperature in the roll-shoe cavity decreases gradually, and the isothermal lines of the alloy deviate from the shoe side to the work roll side in the roll–shoe gap. Metal flow velocity decreases gradually from the surface of the work roll to the surface of the shoe. In the extrusion mould, alloy temperature decreases gradually from the entrance to the exit and from the center to the sidewall of the mould. The extending cavity is radially filled with the alloy. The flow lines in the tube corresponding to the centers of the splitflow orifices and the welding gaps are dense, and the corresponding harness values are high; there are 8 transitional bands between them. In order to prepare 6201 alloy tubes with good surface quality, the pouring temperature from 750 ℃ to 780 ℃ was suggested. 展开更多
关键词 6201 aluminum alloy SEMISOLID rheoforming extrusion EXTENDING TUBE temperature
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Ecosystem health: ecological sustainability target of strategic environment assessment 被引量:1
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作者 陈昆玉 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期146-150,共5页
Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainabili... Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainability target of SEA, the content of ecosystem health as well as the interrelations between SEA and ecosystem health. For a good SEA, its ecological sustainability principles should be provided with distinct content and a general assessment system. A framework for ecosystem health assessment was established according to the content of ecosystem health, and combined into SEA as SEA抯 ecological sustainability target, we can effectively guide decision-makers to make suitable indigenous means and local solutions. , The basic principles and procedure of SEA for ecosystem health are also discussed in the paper. 展开更多
关键词 Environment impact assessment Strategic environmental assessment Ecosystem health
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Application study of dynamic voltage scaling policies
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作者 卜爱国 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期406-409,共4页
Based on the fundamental relationship among the circuit power, the circuit delay and the supply voltage, four theorems associated with the application of dynamic voltage scaling (DVS) policies are proposed and prove... Based on the fundamental relationship among the circuit power, the circuit delay and the supply voltage, four theorems associated with the application of dynamic voltage scaling (DVS) policies are proposed and proved. First, the existence characteristics of the optimal supply voltage for a single task are proved, which suggests that the optimal supply voltage for the single task should be selected only within a one-dimensional term, and the corresponding task end time by the optimal supply voltage should be identical with its deadline. Then, it is pointed out that the minimum energy consumption that the DVS policy can obtain when completing a single task is certainly lower than that of the dynamic power management (DPM) policy or the combined DVS+DPM policy under the same conditions. Finally, the theorem of energy consumption minimization for a multi-task group is proposed, which declares that it is necessary to keep the processor in the execution state during the whole task period to obtain the minimum energy consumption, while satisfying the deadline constraints of any task. 展开更多
关键词 dynamic voltage scaling dynamic power management circuit power circuit delay
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Designand development of highway tunnel maintenance and management system 被引量:4
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作者 葛敏莉 孙璐 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期137-142,共6页
In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effective... In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effectiveness optimal principle objectives under the premise of guaranteeing a smooth flow of traffic; a highway tunnel maintenance and management system framework and the key modules were proposed. First, the determined highway tunnel condition assessment index system was established according to the result of expert consulting forms. Secondly, the tunnel diseases, the corresponding maintenance measurements, and many-to-many relationship between diseases and maintenance measurements were introduced. Then, three kinds of 0-1 integer programming models were built according to different tunnel operators' needs in the optimization decision module. Finally, the further development and implementation of the system was prospected. The research results can provide references to tunnel researchers and managers. 展开更多
关键词 maintenance and management system highwaytunnel condition assessment distress treatment cost-benefitanalysis
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DYNAMIC ENGINEERING DOCUMENT MANAGEMENT BASED ON XML TECHNOLOGY
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作者 翟建军 陈文亮 丁秋林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期38-41,共4页
The eXtensible markup language (XML) is a kind of new meta language for replacing HTML and has many advantages. Traditional engineering documents have too many expression forms to be expediently managed and have no dy... The eXtensible markup language (XML) is a kind of new meta language for replacing HTML and has many advantages. Traditional engineering documents have too many expression forms to be expediently managed and have no dynamic correlation functions. This paper introduces a new method and uses XML to store and manage engineering documents to realize the format unity of engineering documents and their dynamic correlations. 展开更多
关键词 XML dynamic engineering document MANAGEMENT
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Current Situation and Prevention of Soil Erosion from Construction of West-East Natural Gas Transmission (Ningxia-Shaanxi Section) 被引量:1
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作者 李永红 高照良 周茂玲 《Agricultural Science & Technology》 CAS 2012年第6期1320-1327,共8页
In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore prin... In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore principles of pipeline prevention and seek countermeasures. 展开更多
关键词 West-East Natural Gas Transmission Pipeline project Engineering construction Impact on environment Soil erosion
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Prediction of Pressure Drop of Slurry Flow in Pipeline by Hybrid Support Vector Regression and Genetic Algorithm Model 被引量:26
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作者 S.K. Lahiri K.C. Ghanta 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期841-848,共8页
This paper describes a robust support vector regression (SVR) methodology, which can offer superior performance for important process engineering problems. The method incorporates hybrid support vector regression an... This paper describes a robust support vector regression (SVR) methodology, which can offer superior performance for important process engineering problems. The method incorporates hybrid support vector regression and genetic algorithm technique (SVR-GA) for efficient tuning of SVR meta-parameters. The algorithm has been applied for prediction of pressure drop of solid liquid slurry flow. A comparison with selected correlations in the lit- erature showed that the developed SVR correlation noticeably improved the prediction of pressure drop over a wide range of operating conditions, physical properties, and pipe diameters. 展开更多
关键词 support vector regression genetic algorithm slurry pressure drop
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Spatial and temporal variations in cyanobacteria and microcystins in Aha Reservoir,Southwest China 被引量:2
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作者 HAN Mengshu LI Qiuhua +2 位作者 CHEN Hailong XIAO Jing JIANG Fan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第4期1126-1131,共6页
Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. Th... Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. This study was conducted to evaluate the water quality in the Aha Reservoir, Southwest China, focusing on cyanobacteria and cyanotoxins. Water samples were collected weekly or biweekly from May to September of 2015 and used to delineate temporal variations in density and distribution of toxic cyanobacteria and cyanotoxins in the reservoir. Toxic cyanobacteria identified consisted of Aphanizomenon flos-aquae, Pseudanabaena limnetica, Cylindrospermopsis sp., and Microcystis sp., with Aphanizomenon flos-aquae and Pseudanabaena limnetica being the most common and significant toxic genera. The total biomass of cyanobacteria was 17.0 mg/L. Identification and quantification of microcystin variants were conducted by high performance liquid chromatography(HPLC) using a system equipped with a photodiode array detector. Microcystin levels were between 0–3.0 μg/L, MC-RR was around 0–3.0 μg/L and MC-LR was approximately 0–0.9 μg/L. Overall, the results of this study indicate that the investigated reservoirs should be monitored regularly to minimize potential health risks to the human population. 展开更多
关键词 CYANOBACTERIA Aphanizomenonflos-aquae MICROCYSTIN-LR MICROCYSTIN-RR Aha Reservoir
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Numerical Prediction for Subcooled Boiling Flow of Liquid Nitrogen in a Vertical Tube with MUSIG Model 被引量:3
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作者 王斯民 文键 +3 位作者 李亚梅 杨辉著 厉彦忠 JiyuanTu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第11期1195-1205,共11页
Multiple size group (MUSIG) model combined with a threedimensional twofluid model were em ployed to predict subcooled boiling flow of liquid nitrogen in a vertical upward tube. Based on the mechanism of boiling heat... Multiple size group (MUSIG) model combined with a threedimensional twofluid model were em ployed to predict subcooled boiling flow of liquid nitrogen in a vertical upward tube. Based on the mechanism of boiling heat transfer, some important bubble model parameters were amended to be applicable to the modeling of liquid nitrogen. The distribution of different discrete bubble classes was demonstrated numerically and the distribu tion patterns of void fraction in the wallheated tube were analyzed. It was found that the average void fraction in creases nonlinearly along the axial direction with wall heat flux and it decreases with inlet mass flow rate and sub cooled temperature. The local void fraction exhibited a Ushape distribution in the radial direction. The partition of the wall heat flux along the tube was obtained. The results showed that heat flux consumed on evaporation is the leading part of surface heat transfer at the rear region of subcooled boiling. The turning point in the pressure drop curve reflects the instability of bubbly flow. Good agreement was achieved on the local heat transfer coefficient aalnst experimental measurements, which demonstrated the accuracy of the numerical model. 展开更多
关键词 liquid nitrogen subcooled boiling bubble departure diameter bubble frequency nucleation site den-sity MUSIG model
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Traditional Ecological Knowledge and Community-based Natural Resource Management in Northeast India 被引量:2
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作者 S.C. Rai 《Journal of Mountain Science》 SCIE CSCD 2007年第3期248-258,共11页
Community-based natural resource management in northeast India has a long history. Indigenous knowledge and adaptation are the collective information, with improvement from generation to generation. The expectation is... Community-based natural resource management in northeast India has a long history. Indigenous knowledge and adaptation are the collective information, with improvement from generation to generation. The expectation is that under community control, local expertise on biodiversity will play a significant role in natural resource management through traditional practices. This paper discusses the characteristics and application of the traditional ecological knowledge of aboriginal peoples in northeast India and its role in natural resource management. Examples are provided in two different eco-cultural landscapes, i.e., Demazong (the Buddhist eco-cultural landscape in Sikkim Himalaya) and the Apatani eco-cultural landscape in Arunachal Pradesh, which illustrate the utility value of traditional ecological knowledge in sustainable natural resource management. Both eco-cultural landscapes are indeed very complex and highly evolved systems with high levels of economic and ecological efficiencies. The paper concludes that traditional ecological knowledge systems and institutions could serve as entry points into the sustainable utilization and management of natural resources. This could be achieved through the exploration of the cultural practices of the local people and integrating useful aspects into the modern natural resource management expertise. With rapidly depleting biodiversity in the developing tropic regions, there is a greater utilization today than ever before of the value of respecting the "Sacred" as a tool towards better conservation of natural resources. 展开更多
关键词 Traditional ecological knowledge resource management cultural landscape sustainable development northeast India
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