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在线医疗平台信息生态系统的生态性评价指标体系研究
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作者 赵英 肖垚 +1 位作者 李佳 许世金 《情报理论与实践》 CSSCI 北大核心 2024年第7期59-68,共10页
[目的/意义]在线医疗平台作为一类典型的信息生态系统,其可持续发展依赖于生态性水平。构建生态性评价指标体系,不仅是对在线医疗平台评价指标体系的必要补充,还有助于拓展生态性评价的研究场景。[方法/过程]基于信息生态理论,利用德尔... [目的/意义]在线医疗平台作为一类典型的信息生态系统,其可持续发展依赖于生态性水平。构建生态性评价指标体系,不仅是对在线医疗平台评价指标体系的必要补充,还有助于拓展生态性评价的研究场景。[方法/过程]基于信息生态理论,利用德尔菲法和层次分析法,以DPSIR模型为基础,构建了由“驱动力—压力—状态—影响—响应”5个维度构成的在线医疗平台信息生态系统的生态性评价指标体系。[结果/结论]在线医疗平台应着力于内在动力的激发;信息生态位重叠问题是平台压力的主要来源;提升社会和同行对在线医疗平台的评价是改善平台状态的重要抓手;增强资源吸引力和资源巩固力是提高平台影响力的关键;系统创新能力是强化平台响应能力的重要因素。 展开更多
关键词 在线医疗平台 信息生态理论 DPSIR模型 生态性评价指标体系
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简述城市道路绿化景观生态量化的设计方法 被引量:1
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作者 袁婷 《农业与技术》 2023年第7期105-107,共3页
本文针对城市道路绿化景观的生态设计问题进行研究,构建城市道路绿化生态性量化指标体系,介绍了该量化指标体系的评价方法,结合海口市滨海大道进行实例分析。实践表明:对城市道路绿化的生态性进行量化评价,能准确发现当前道路绿化存在... 本文针对城市道路绿化景观的生态设计问题进行研究,构建城市道路绿化生态性量化指标体系,介绍了该量化指标体系的评价方法,结合海口市滨海大道进行实例分析。实践表明:对城市道路绿化的生态性进行量化评价,能准确发现当前道路绿化存在的问题,探索提高城市道路绿化生态性的建议措施,推动整个城市高质量发展。 展开更多
关键词 城市道路 生态性指标 量化研究 影响因子
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Effects of Probiotics on Growth Performance and Blood Biochemical Indexes of Cherry Valley Ducks 被引量:4
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作者 李小芬 杨晓志 +3 位作者 陶勇 张玲 顾文婕 袁旭红 《Agricultural Science & Technology》 CAS 2015年第8期1732-1734,1740,共4页
In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. To... In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight (P〈0.05) of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood (P〈0.05) and reduce the creatinine content and total cholesterol content in Cherry Valley ducks (P〉0.05); at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic. 展开更多
关键词 Cherry Valley duck Probiotic Growth performance Blood biochemicalindex Economic benefits
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Research Progress of Heat-tolerance of Brassica campestris ssp. Chinensis 被引量:5
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作者 赵晓东 张景云 +1 位作者 范淑英 缪南生 《Agricultural Science & Technology》 CAS 2013年第2期248-253,共6页
Brassica campestris ssp. chinensis, also known as non-heading Chinese cabbage, is an important vegetable widely distributed in southern China. High temperature is the most common adversity factor in vegetable producti... Brassica campestris ssp. chinensis, also known as non-heading Chinese cabbage, is an important vegetable widely distributed in southern China. High temperature is the most common adversity factor in vegetable production, because Brassica campestris ssp. chinensis is a thermophilic vegetable, which can't well grow at high temperature. In summer and autumn, high temperature stress would prevent Brassica campestris ssp. chinensis from growing and result in poor quality of its seedlings, seriously influencing yield and quality of the vegetable in later period. In this paper, present situation and latest advances in heat resistance research of Brassica campestris ssp. chinensis in recent years were reviewed at home and abroad. The research tendency in Bassica campestris ssp. chinensis was also described, providing reference for breeding of heat-resistant Brassica campestris ssp. chinensis. 展开更多
关键词 Brassica campestris ssp. chinensis High temperature stress Morphological index Physiological and biochemical indexes Heat tolerance
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Micromorphological Evidences of Climatic Change in Yazd Region,Iran 被引量:2
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作者 Ruhollah Taghizadeh Mehrjardi Shahla Mahmoodi +1 位作者 Ahmad Heidari Ali Akbarzadeh 《Journal of Mountain Science》 SCIE CSCD 2009年第2期162-172,共11页
The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past .time, particularly the paleoclimate. In this respect the micro- morphologi... The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past .time, particularly the paleoclimate. In this respect the micro- morphological properties showed to be a very good indicator. Therefore, for investigating of climate change in Ardakan-Yazd plain, Central Iran 9 pedons were digged and described. Yazd has an arid climate with less than 100 mm annual precipitation and more than 22℃ mean annual temperature (Aridic-hyper thermic soil moisture and temperature regions, respectively). Based on the morphological and physicochemical analysis Arglic, Calcic and Gypsic diagnostic horizons have been distinguished in these soils. Thin section studied showed that the illuviated form of clay includes, infillings on channel, coating on pendant, on nodules and on grains, at lower depths and also juxtaposed calcite needles on void argillan at upper part of the profiles. Mineralogical result showed fine clay in arglic horizon, too. Considering depth and forms of these pedofeatures, we concluded that, the observed illuviated clays at lower depth must be the result of the more humid climate of the past, where the carbonates have been removed completely as pendant, nodules or coating to considerable depth, following processes, clay has been dispersed and also trans located to these depths. In contrast to these features, the juxtaposed needle calcite at the shallower depth is probably the result of drier climate of today. 展开更多
关键词 Micromorphologieal indicators CLIMATECHANGE Arglic horizon Yazd region
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Taxonomic Distinctness of Macrofauna as an Ecological Indicator in Laizhou Bay and Adjacent Waters 被引量:9
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作者 ZHOU Hong HUA Er ZHANG Zhinan 《Journal of Ocean University of China》 SCIE CAS 2010年第4期350-358,共9页
In this paper, we assessed the ecological and biodiversity status in the Bohai Sea through a quantitative survey on mac-rofaunal community at 25 stations in Laizhou Bay and adjacent waters in the autumn of 2006.We tes... In this paper, we assessed the ecological and biodiversity status in the Bohai Sea through a quantitative survey on mac-rofaunal community at 25 stations in Laizhou Bay and adjacent waters in the autumn of 2006.We tested the robustness and effectiveness of taxonomic distinctness as an ecological indictor by analyzing its correlation with species richness and natural environmental variables and by analyzing other ecological indicators (Shannon-Wiener H' and W statistics from Abundance Biomass Comparison curve).Results so obtained indicated that the benthic environment of the study waters in general is not under major impact of anthropogenic disturbance, but some stations in Laizhou Bay and along the coast of the Shandong Peninsula and even in the central Bohai Sea might be moderately disturbed and showed signs of ecological degradation.The taxonomic distinctness measures △+ and Λ+ were independent of sampling effort and natural environment factors and were compliant to other ecological indicators.Further application of the taxonomic distinctness indicator to assess marine biodiversity and ecosystem health on a larger regional scale with historical data seems promising. 展开更多
关键词 Taxonomic distinctness MACROFAUNA ecological indicator BIODIVERSITY Laizhou Bay Bohai Sea
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Urban ecological sustainability assessment of the human-made system and natural system based on emergy and GIS approach
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作者 Zhang Junxue Li Shan 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期75-83,共9页
Due to the complexity of sustainable urban research,the environmental sustainability was assessed.Taking the sponge city as an example,the case study was conducted based on the integrated geographic information system... Due to the complexity of sustainable urban research,the environmental sustainability was assessed.Taking the sponge city as an example,the case study was conducted based on the integrated geographic information system(GIS)and emergy methods.The results demonstrate that the emergy of agricultural crops,major industrial products,comprehensive energy products,imports and exports,waste products and increased natural system emergy are the decisive factors for the sustainability assessment.Agricultural crops are the primary contributor,which accounts for 48.9%of the total emergy amount.Urban solid waste has a self-evident superiority in the waste products emergy proportion.Surface water and vegetal biomass emergy possess the pivotal consequences,far higher than soil organic matter.The sewage treatment stations(0.11%)play a small role in the sustainability assessment of the sponge city.The emergy sustainability index is 0.02181,which indicates poor environmental sustainability.According to the study results,increasing renewable energy input proportion and adopting the vegetal biomass of high unit emergy values(UEVs)can improve the sustainability level. 展开更多
关键词 sponge city emergy analysis geographic information system(GIS) ecological indicators sustainability evaluation
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Preliminary study on road-region ecosystem stability evaluation 被引量:1
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作者 QIN Zhi-bin LIU Zhao-hui LI Yu-zhi 《Journal of Environmental Science and Engineering》 2008年第5期48-54,共7页
A scientific and rational evaluation on road-region ecosystem stability is the premise to properly deal with the relationship between highway constructing and ecological environment protecting to a sustainable develop... A scientific and rational evaluation on road-region ecosystem stability is the premise to properly deal with the relationship between highway constructing and ecological environment protecting to a sustainable development. Based on the connotative meaning and the procedure of evaluation on road-region ecosystem stability, this paper studied the principles and the method on determining the evaluation index system on road-region ecosystem stability. It put forward an index system for assessing road-region ecosystem stability as a reference. On the basis of detailed analyze of the multidimensional space of road-region ecosystem, a new multi-objective comprehensive evaluation method for road-region ecosystem stability is presented and a calculation tormula for multi-objective comprehensive level of road-region ecosystem stability. This method was used to evaluate road-region ecosystem stability of Lin-Chang highway. This method possessed definite theoretical value and reliability in practice. 展开更多
关键词 road-region ecosystem evaluation of stability MULTI-OBJECTIVE multidimensional space
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The Diversity of the Environmental Impact in Kurzeme
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作者 Imants Liepa Oskars Zalkalns 《Journal of Life Sciences》 2014年第7期570-581,共12页
The analysis of environmental impact effects on forest ecosystems has a theoretical and practical nature. Many methods have been developed to determine characteristics and intensity of this impact. Methodologically, t... The analysis of environmental impact effects on forest ecosystems has a theoretical and practical nature. Many methods have been developed to determine characteristics and intensity of this impact. Methodologically, they can be divided into three groups: environmental parameter, bioindicative and combined methods. To evaluate the environmental impact a combined method was used in this study, it was based on trees as the bioindicators and their response reactions, and environmental parameter analysis. In this study the bioindicator was Norway spruce (Picea abies (L.) Karst.), whose response reaction was used to explain total impact volumes of environmental factors in different places in the region of Kurzeme and try to interpret the causes of these differences. As the bioindicators criterion was used response reaction of Norway spruce during a period of 20 years, which was expressed with cumulative and annual additional volume increment, and was depending on the location of the stand and its morphometric characteristics. The empirical material was collected in Kurzeme region in 28 sample plots that are located on two transects and in one reference stand. For the evaluation the widths of the last 40 year growth rings were measured. To express the environmental impact in Kurzeme region a multiple regression model was developed, which explains the environmental impact in the volume of 68.2%, the rest part can be explained by the local conditions of each stand. It must be noted that methodology used in this study is very sensitive, thus, each of the nuances in the dynamics of volume's annual reduced additional increments has biological and ecological cause. 展开更多
关键词 Norway spruce additional volume increment BIOINDICATION environmental impact.
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A DISCRETE-TIME Geo/G/1 RETRIAL QUEUE WITH J-VACATION POLICY AND GENERAL RETRIAL TIMES 被引量:4
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作者 YUE Dequan ZHANG Feng 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第4期556-571,共16页
The authors discuss a discrete-time Geo/G/1 retrial queue with J-vacation policy and general retrial times.As soon as the orbit is empty,the server takes a vacation.However,the server is allowed to take a maximum numb... The authors discuss a discrete-time Geo/G/1 retrial queue with J-vacation policy and general retrial times.As soon as the orbit is empty,the server takes a vacation.However,the server is allowed to take a maximum number J of vacations,if the system remains empty after the end of a vacation.If there is at least one customer in the orbit at the end of a vacation,the server begins to serve the new arrivals or the arriving customers from the orbit.For this model,the authors focus on the steady-state analysis for the considered queueing system.Firstly,the authors obtain the generating functions of the number of customers in the orbit and in the system.Then,the authors obtain the closed-form expressions of some performance measures of the system and also give a stochastic decomposition result for the system size.Besides,the relationship between this discrete-time model and the corresponding continuous-time model is also investigated.Finally,some numerical results are provided. 展开更多
关键词 DISCRETE-TIME generating function J-vacation policy Markov chain retrial queue.
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