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Assessment of Direct Eco-value of Liangzi Lake
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作者 封瑛 李兆华 刘化吉 《Agricultural Science & Technology》 CAS 2013年第6期882-885,共4页
[Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environm... [Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environment was introduced and the productivity of the lake was investigated both through the literature materials and the investigations. The market value method was clarified in this paper as well as its operation process and the application fields. [Result] Based on the introduction of the current situation in Liangzi Lake, the direct usage value was estimated as 1.32 billion Yuan/year. Plant resources value was 318 million Yuan/year; animal resources value was 675 million Yuan/year; and water storage value was 325 million Yuan/year for the three parts. [Conclusion] This paper will attract more attention to the emphasis of the reasonable development of nature sources. 展开更多
关键词 Valuation assessment direct usage value Market value method Liangzi Lake
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ON THE SINGULAR DIRECTIONS OF VALUE DISTRIBUTION OF HOLOMORPHIC CURVES IN P^n(C) 被引量:2
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作者 涂振汉 李平丽 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期702-710,共9页
This article proves the existence of singular directions of value distribution theory for some transcendental holomorphic curves in the n-dimensional complex projective space P^n(C).. An example is given to compleme... This article proves the existence of singular directions of value distribution theory for some transcendental holomorphic curves in the n-dimensional complex projective space P^n(C).. An example is given to complement these results. 展开更多
关键词 Complex projective spaces holomorphic mappings normal families singular directions and value distribution theory
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Value of direct vision internal urethrotomy in treatment of urethral stricture-twenty-year clinical experience
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作者 张炯 《外科研究与新技术》 2011年第4期254-254,共1页
Objective To summarize the experience and evaluate the efficacy of treatment of urethral stricture using direct visual internal urethrotomy ( DVIU) . Methods The clinical data of 361 patients ( age range 16 - 72 years... Objective To summarize the experience and evaluate the efficacy of treatment of urethral stricture using direct visual internal urethrotomy ( DVIU) . Methods The clinical data of 361 patients ( age range 16 - 72 years, mean age 38 years) with urethral stricture who underwent urethrotomy from 1990 to 2010 was retrospectively ana- 展开更多
关键词 LENGTH THAN value of direct vision internal urethrotomy in treatment of urethral stricture-twenty-year clinical experience
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Community Perception of Riparian Corridors Ecosystem Services and Implications for Environmental Education in Upper Oueme Catchment in Benin, West Africa
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作者 Socrate Mercator Dossou Kinnoumè Serge Adomou +1 位作者 Gérard Nounagnon Gouwakinnou Thierry Dèhouégnon Houéhanou 《Open Journal of Ecology》 2024年第2期125-147,共23页
The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the per... The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the perception and importance attributed to the ecosystem services (ESs) provided by riparian corridors in 368 households across 70 villages located in a buffer zone of 5 km of servitude around the permanent rivers of the Upper Oueme watershed in Benin. We found that local communities easily reported provisioning and cultural ESs than regulating and supporting ones, indicating their misunderstanding of the main role of riparian corridor. Moreover, the supply of cropping areas was perceived as the most important ES. Educated respondents and high-income households had more knowledge of regulating ESs and supporting ESs, respectively. Overall, the highly perceived importance of the provision of cropping areas indicates a potential risk of agricultural encroachment of riparian corridors. We suggest the consideration of the current local perception of riparian corridor’s role in designing a sound environmental education aiming at the change of local population’s perception. This perception shift will promote a sustainable management of the riparian corridors. 展开更多
关键词 Local Knowledge direct Use value Soil Formation Migration Importance value BENIN
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New model for deducing directional extrema based on multivariate extremum statistical theory 被引量:2
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作者 王莉萍 刘天娇 韩润雨 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1323-1328,共6页
The parameters of principal and directional extrema in a marine environment are important in marine engineering design, especially for appropriate construction of oceanic platforms and other structures. When designing... The parameters of principal and directional extrema in a marine environment are important in marine engineering design, especially for appropriate construction of oceanic platforms and other structures. When designing wave walls and break water structures, the orientation of the breakwater or seawall depends mainly on the direction of the strongest waves. However, the strength of the breakwater and the elevation of the seawall depend on the magnitude of the biggest wave height of the strongest waves. Thus, identification of directional extrema plays an important role in the design of wave factors. When calculating the directional extremum, different materials may require different specific computational methods, yet few theoretical studies have been conducted in this field of research. Based on multivariate extremnm statistical theory, this paper utilizes a discrete random variable to build a joint probability model compounded by a discrete random variable and a multivariate continuous random variable. Furthermore, this paper provides the first investigation on the theories and methodologies to deduce wave directional extrema. The results provide tools for both creating the calculation method of the directional extremum value and providing the rational directional extremum parameters for marine engineering design. 展开更多
关键词 discrete random variable multivariate extreme value directional extreme value statisticaltheory joint probability mode
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