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苏北农村现代化商贸流通市场体系的构建、评价及发展对策 被引量:10
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作者 周桂良 毛丽娜 +1 位作者 吴鼎新 赵钢 《江苏农业科学》 北大核心 2014年第2期385-387,共3页
苏北农村商贸流通现代化程度还不高,商贸流通市场体系还不健全。通过6个子体系完整地构建了苏北农村现代化商贸流通市场体系,在选取5个一级指标和13个二级指标的基础上建立苏北农村现代化商贸流通市场评价指标体系并进行评价分析。结果... 苏北农村商贸流通现代化程度还不高,商贸流通市场体系还不健全。通过6个子体系完整地构建了苏北农村现代化商贸流通市场体系,在选取5个一级指标和13个二级指标的基础上建立苏北农村现代化商贸流通市场评价指标体系并进行评价分析。结果表明,苏北农村农产品购销体系对苏北农村现代化商贸流通市场影响最大。最后相应地提出了推进"四大流通方式"、完善"四大流通网络"、构建"四大平台"和落实"四大保障"的发展对策。 展开更多
关键词 苏北农村 商贸流通市场体 构建 系价 发展对策
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TODGA-DHOA体系萃取金属离子 Ⅲ.对Am(Ⅲ)和三价镧系离子的萃取 被引量:11
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作者 朱文彬 叶国安 李峰峰 《核化学与放射化学》 CAS CSCD 北大核心 2014年第1期24-33,共10页
研究了以N,N,N’,N’-四辛基-3-氧戊二酰胺(TODGA)和N,N-二己基辛酰胺(DHOA)为萃取剂、正十二烷为稀释剂对Am(Ⅲ)和三价镧系元素的萃取行为,主要考察了萃取剂浓度、HNO3浓度、NaNO3浓度、金属离子浓度和温度的影响。结果表明:随着TODGA... 研究了以N,N,N’,N’-四辛基-3-氧戊二酰胺(TODGA)和N,N-二己基辛酰胺(DHOA)为萃取剂、正十二烷为稀释剂对Am(Ⅲ)和三价镧系元素的萃取行为,主要考察了萃取剂浓度、HNO3浓度、NaNO3浓度、金属离子浓度和温度的影响。结果表明:随着TODGA浓度的增加,TODGA/正十二烷和TODGA-DHOA/正十二烷两种萃取体系对Am(Ⅲ)和三价镧系元素的萃取分配比显著增加,DHOA对三价锕系和镧系萃取能力很弱,而DHOA的加入,对TODGA/正十二烷萃取Am(Ⅲ)和三价镧系元素具有一定抑制作用。TODGA萃取三价镧系元素的分配比随着镧系原子序数的增加而增加,Am的分配比与Eu相近。TODGA萃取稀土元素是放热反应,萃取过程中焓变起主导作用,吉布斯自由能变(-ΔG)变化的规律也表明随着镧系原子序数的增加,TODGA对其萃取能力增强。通过对TODGA萃取Am(Ⅲ)和三价镧系元素机理探讨,得到萃取反应方程式均为:M3+aq+3NO-3,aq+3TODGAorg→M(NO3) 展开更多
关键词 TODGA DHOA 溶剂萃取 Am(Ⅲ)
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洗扫车高压水系统清洗能力的评价与计算 被引量:3
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作者 肖庆麟 覃先云 《建设机械技术与管理》 2018年第1期54-57,共4页
针对洗扫车行车作业的特点创新性地提出了利用喷嘴打击力、喷杆单位面积打击能量和喷杆单位面积清洗水量这三个参数综合评价洗扫车高压水系统的清洗能力。以某典型洗扫车为例,详细介绍了如何获得以上三个评价参数的计算方法。对清洗喷... 针对洗扫车行车作业的特点创新性地提出了利用喷嘴打击力、喷杆单位面积打击能量和喷杆单位面积清洗水量这三个参数综合评价洗扫车高压水系统的清洗能力。以某典型洗扫车为例,详细介绍了如何获得以上三个评价参数的计算方法。对清洗喷杆的四种喷嘴布置方案的清洗能力进行对比分析表明,侧喷杆能力明显大于中喷杆,其能力是中喷杆的1.8~2.4倍;将侧喷杆的喷嘴型号由原来的A型更改为B型,使喷杆之间清洗能力差值明显降低,有利于提高路面整体清洗效果。试验测试结果进一步验证了本文方法的正确性。 展开更多
关键词 洗扫车 高压水 清洗能力 与计算
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镧系金属-有机框架材料作为荧光探针的研究进展 被引量:5
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作者 初红涛 尹杰 +4 位作者 林清 隋秉蓉 谭金铭 苏立强 马文辉 《材料导报》 EI CAS CSCD 北大核心 2022年第16期209-216,共8页
金属-有机框架(Metal-organic frameworks,MOFs)材料是由配位键将金属离子与有机配体连接而形成的结构有序的网状配合物,在离子交换、气体分离及存贮、催化、荧光传感及药物输送等领域具有重要的应用价值。利用具有荧光发射特性的MOFs... 金属-有机框架(Metal-organic frameworks,MOFs)材料是由配位键将金属离子与有机配体连接而形成的结构有序的网状配合物,在离子交换、气体分离及存贮、催化、荧光传感及药物输送等领域具有重要的应用价值。利用具有荧光发射特性的MOFs与客体分子作用后荧光强度的变化,可实现对目标组分的定量检测,而仅依靠单一配体发光的MOFs,定量方法易受外界条件的干扰,会影响结果准确性。金属离子和有机配体的性质决定了MOFs的荧光特性,是该领域学者们研究的重点。镧系元素的三价离子(Ln)具有未被完全充满的4f电子层结构,其荧光性能独特,易与氧、氮原子配位,且可与有机配体配位形成具有特殊拓扑结构的高配位配合物。Ln与有机配体形成的镧系金属-有机框架(Ln-MOFs)材料除了具有结构有序、比表面积大的特点外,同时结合了有机配体和镧系元素二者的荧光特性,作为比率型荧光探针被广泛应用。选择不同的有机配体及镧系元素,可开发出对不同组分产生响应的Ln-MOFs。本文对近年来Ln-MOFs在阴、阳离子以及小分子的荧光检测及温度传感方面的研究进展进行了综述,并对其检测结果、检测机理及影响因素等进行了分析,然后对Ln-MOFs材料作为荧光探针的设计理念进行了总结,最后对Ln-MOFs研究中存在的问题进行了分析,并对其未来发展进行了展望。 展开更多
关键词 金属-有机框架材料 荧光探针 离子 发光功能应用
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论国企体制改革与社会保障体系应变
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作者 何伟 《中国保险管理干部学院学报》 2001年第6期3-4,共2页
当前,国有企业体制改革已进入全面攻坚阶段,中心任务是通过体制创新,将企业由原来政府的附属物改造成为自主经营、自负盈亏、自我约束、自我发展的独立法人实体和市场竞争主体,建立现代企业制度。经济体制转轨要求国企实现由粗放型... 当前,国有企业体制改革已进入全面攻坚阶段,中心任务是通过体制创新,将企业由原来政府的附属物改造成为自主经营、自负盈亏、自我约束、自我发展的独立法人实体和市场竞争主体,建立现代企业制度。经济体制转轨要求国企实现由粗放型经济增长方式向集约型经营增长方式转变,通过战略性改组,缩短国企运作战线,提高运作质量,整体搞活国有经济。为此,国企以失业和下岗的方式释放出一批在计划经济体制下为承担社会就业任务而沉淀的过剩过去力。如果经济体制转轨能在本世纪前十年基本完成,预计还将向社会释放1/3以上的过剩劳动力,约3000万到3500万人^[1]。由于社会保障体系不健全,下岗职工对失业、养老、医疗等社会保障存在后顾之忧,不愿脱离与企业的劳动关系而滞留于原单位,成为制约国企绵重要因素。因此,建立和健全社会保障体系显得十分必要。 展开更多
关键词 国有企业 体制改革 社会保障
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东江河口典型河段溶解氧时空动态及低氧成因解析
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作者 黄广灵 黄本胜 +2 位作者 刘达 邱静 黄国如 《湖泊科学》 EI CAS 北大核心 2025年第1期112-121,共10页
为解析东江南支流低氧现象的成因,并为水环境治理提供科学依据,本研究分别于2019年春季和夏季对该河流的主要断面进行了水质监测。监测结果显示,东江南支流的溶解氧(DO)水平从中游道滘镇的6.93 mg/L降至出海口处的4.08 mg/L。DO与影响... 为解析东江南支流低氧现象的成因,并为水环境治理提供科学依据,本研究分别于2019年春季和夏季对该河流的主要断面进行了水质监测。监测结果显示,东江南支流的溶解氧(DO)水平从中游道滘镇的6.93 mg/L降至出海口处的4.08 mg/L。DO与影响因子的相关性分析显示,DO与水温呈显著负相关,与盐度呈正相关,而与氨氮和总磷等营养物质呈显著负相关。这些营养物质的增加与DO的降低在空间上呈显著重叠,特别是在夏季。研究结果表明,东江南支流低氧现象受物理、化学和生物因素的共同影响,其中温度升高和营养物质浓度增加使得中下游水体的氧气消耗加快,河道汇流处的断面缩窄和下游水体的透光性差引起DO补给不足,从而导致下游沙田泗盛断面经常性出现氧亏(低氧)现象。 展开更多
关键词 东江南支流 溶解氧 低氧 营养物 珠江
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E-government maturity model and its evaluation 被引量:4
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作者 黄梦醒 邢春晓 杨吉江 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期389-392,共4页
In order to ensure e-government construction healthily,rapidly and orderly develop,an e-government maturity model(EGMM)is proposed based on a software capability maturity model (CMM)and a project management maturi... In order to ensure e-government construction healthily,rapidly and orderly develop,an e-government maturity model(EGMM)is proposed based on a software capability maturity model (CMM)and a project management maturity model(PMMM). Five levels of maturity in e-government development process are constructed,which include network infrastructure,information serving,information interactive,information sharing and comprehensive integrating.An index system of e-government maturity is put forward,and then an e-government maturity levels evaluation method is presented,which can provide clear,detailed and efficient decision information and investment directions of e-government for decision-makers.The EGMM and its maturity evaluation method are helpful for improving the construction of e-government. 展开更多
关键词 E-GOVERNMENT maturity model index system EVALUATION
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Study and Implementation on the Grey Comprehensive Evaluation Support System of Ecocity 被引量:2
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作者 黄鹍 陈森发 +1 位作者 孙燕 亓霞 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期356-360,共5页
According to basic connotation and design principles of ecocity, a comparatively integrated index system is constructed in the paper. And at the same time using hierarchy grey comprehensive evaluation method, a hierar... According to basic connotation and design principles of ecocity, a comparatively integrated index system is constructed in the paper. And at the same time using hierarchy grey comprehensive evaluation method, a hierarchy grey comprehensive evaluation model of ecocity is established, then on the basis of the model, a comprehensive evaluation support system is developed, and the theoretical guidance supplied for construction of ecocity is provided. 展开更多
关键词 ecocity index system evaluating level hierarchy grey comprehensive evaluation evaluation support system
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REVIEW OF ACUPUNCTURE FOR FROZEN SHOULDER 被引量:5
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作者 彭唯娜 王漪 +2 位作者 刘保延 刘志顺 毛湄 《World Journal of Acupuncture-Moxibustion》 2007年第2期1-15,共15页
Objective To assess the efficacy and possible adverse effects of acupuncture on frozen shoulder. Methods Based on the key words, i.e. acupuncture, electroacupuncture, acupuncture-moxibustion, frozen shoulder, adhesive... Objective To assess the efficacy and possible adverse effects of acupuncture on frozen shoulder. Methods Based on the key words, i.e. acupuncture, electroacupuncture, acupuncture-moxibustion, frozen shoulder, adhesive capsulitis, shoulder disorders etc., the Chinese databases were retrieved, including Oochrane Musculoskeleta Group, Oochrane Controlled Trials Register, Oochrane Complementary Medicine Field, and the central database of the Oochrane Library as well as MEDLINE, EMBASE and Chinese Biomedical CD (OBM-disc). 20 Chinese medical journals and relevant academic conference proceedings have been searched manually. The reference lists of identified documents were checked as the supplementary retrieval. Results 6 randomized controlled trials on frozen shoulder with acupuncture and electroacupuncture were included, indicating quite advanced study quality. There were 34 to 257 participants in the trials, 668 in total. The total OR of CMS/OSA was OR 3.49 (95 % CI - 2.64 to 9.63), the total OR of VAS was OR - 1.24 (95% CI -3.50 to 1.01), the total OR of ROM was OR 35.70 (95% CI 22.91 to 48.49); the total OR of MELLE was OR 4.30 (95% OI 2.32 to 7.98). Conclusion It is shown in the present limited inclusive trials on frozen shoulder that acupuncture is the safe therapy and effective on improving the global function, relieving pain, and improving the range of motion of shoulder. All the therapeutic effects of acupuncture are superior to those in control group. However, much more high quality trials are required to provide much stronger evidence. Additionally, much more evidences on validity of frozen shoulder with other assessing indexes involved are required in the treatment with acupuncture. 展开更多
关键词 Acupuncture Frozen shoulder Systematic review Control
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Scales,methods and technical analysis of China's residential environment evaluation 被引量:2
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作者 李绥 石铁矛 周乐 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期274-277,共4页
To improve China's residential environment evaluation system and enhance its guiding role, current research results are analyzed and summarized from three aspects including research scales, evaluation methods and app... To improve China's residential environment evaluation system and enhance its guiding role, current research results are analyzed and summarized from three aspects including research scales, evaluation methods and applied technology by means of comparison, induction and empirical application. The guiding role of the current macro-scale evaluation system of urban planning and construction is generally not obvious, whereas the guiding role of medium and micro-scale systems to the improvement of residential environments is improving. There are diversified methods for determining the threshold values and the weights of indices in China's evaluation system. For instance, the analytic hierarchy process(AHP) method is adopted to determine the weights of indices. The advantages and disadvantages of the method are analyzed on the basis of empirical calculation. In the course of comprehensive analyses, a nonlinear model can reflect interactions among indices more than a linear model; the evaluation model under the ARCGIS platform prevails since it combines space and attribute, and it has intuitive results. So far, the methodological system of China's residential environment evaluation has not been established; its subject coverage and research category should be expanded, and its guiding role should be enhanced. 展开更多
关键词 residential environment evaluation system SCALE threshold value WEIGHT evaluation model geographic information system (GIS)
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Study on the evaluation index system and evaluation method for self-elevating drilling unit design 被引量:1
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作者 王运龙 纪卓尚 《Journal of Marine Science and Application》 2009年第1期46-52,共7页
In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and me... In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis (GRA), in which the analytic hierarchy process (AHP) was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms. 展开更多
关键词 self-elevating drilling unit evaluation index system evaluation method grey relation analysis (GRA) analytic hierarchy process (AHP)
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Seagrass Bed Ecosystem Service Valuation——A Case Research on Hepu Seagrass Bed in Guangxi Province 被引量:3
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作者 韩秋影 黄小平 +1 位作者 施平 张景平 《Marine Science Bulletin》 CAS 2008年第1期87-96,共10页
Seagrass bed ecosystem is a coastal ecosystem with abundant biodiversity and high production. It is also an important system for the sustainable development of human society and economy. Based on the local research, s... Seagrass bed ecosystem is a coastal ecosystem with abundant biodiversity and high production. It is also an important system for the sustainable development of human society and economy. Based on the local research, statistical data and prevenient research results, the main services of Hepu seagrass ecosystem were analyzed in the paper, including fishing production, nutrient cycling, scientific research, protecting the coast from eroding, climate regulation, biodiversity, culture, bequest valuation, option valuation and existence valuation and so on. At the same time, we used ecological and economic methods for economic evaluation of seagrass in Hepu of Guangxi, including the market valuation method, contingent valuation method, carbon and tax method, benefit transfer method and expert survey method. The results showed that the total valuation of the Hepu seagrass ecosystem service was about 6.29 × 10^5 Yuan RMB/ha in 2005. Among these services, the indirect using valuation is the main aspect, which was 4.47 x 10^5Yuan RMB/ha in 2005, accounting for 70.97 % of the total valuation. The non-using valuation was 1.54 × 10^5 Yuan RMB/ha in 2005, accounting for 24.52 % of the total valuation. The direct using valuation is the least, which was only 2.84 × 10^4 Yuan RMB/ha in 2005, accounting for 4.51% of the total valuation. 展开更多
关键词 Seagrass bed ecosystem service VALUATION Hepu South China
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Price linkage between Chinese and international nonferrous metals commodity markets based on VAR-DCC-GARCH models 被引量:16
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作者 岳意定 刘笃池 徐珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期1020-1026,共7页
Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal pric... Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal prices from London Metal Exchange(LME).The results show that LME nonferrous metals prices still have a greater impact on Chinese nonferrous metals prices.However,the impact of Chinese nonferrous metals prices on LME nonferrous metals prices is still weak except for lead price.The co-movement of nonferrous metal prices between LME and China presents hysteretic nature,and it lasts for 7-8trading days.Furthermore,the co-movement between LME nonferrous metals prices and Chinese nonferrous metals prices has the characteristics of time-varying,and the correlation of lead prices between LME and China is the more stable than all other nonferrous metals prices. 展开更多
关键词 price linkage nonferrous metals commodity prices Chinese metals commodity market LME CO-MOVEMENT VAR model DCC-GARCH model
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Assessment of Ecosystem Services Value in Hotan Oasis, Xingjiang 被引量:3
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作者 杨依天 王平 +2 位作者 黄宇 张月从 郭翠恩 《Agricultural Science & Technology》 CAS 2013年第3期425-432,共8页
[Objective] The study aimed to assess the ecosystem services value in Hotan Oasis, Xingjiang. [Method] The visual interpretation method was adopted to process TM/ETM+ images based on field investigation in Hotan Oasi... [Objective] The study aimed to assess the ecosystem services value in Hotan Oasis, Xingjiang. [Method] The visual interpretation method was adopted to process TM/ETM+ images based on field investigation in Hotan Oasis. These inter- pretation data, along with two periods of land use data, were reclassified to farm- land, forest, grassland and so on. Then, the ecosystem services value was calculat- ed and analyzed. [Result] Analysis indicated that the ecosystem services value had been increased by 30.44x108 Yuan (16.51%) in the study area during 1980-2010, which can be explained by the increase of glacier and snowfield distributed in the south mountain with the increase of annual precipitation. At the same time, the con- tribution rate of grassland to ecosystem services value had been decreased as a result of degradation of grassland and occupation from farmland. For the whole basin, the increase of ecosystem services value came from the upper reaches, while the ecosystem services value had been reduced in the middle and lower reaches. In the middle reaches, the reduction came mainly from wetland (-1.83x10s Yuan), waters (-1.68x10s Yuan), forest (-0.86x108 Yuan) and grassland (-0.80x108 Yuan). But in the lower reaches, the ecosystem services values of waters, grassland and forest were -0.61 x108 Yuan, -0.24x108 Yuan, and -0.07x10s Yuan, respectively. [Conclusion] If some effective policies, such as the implementation of returning farm- land to forest and ceasing from farming to grazing, would be taken, the ecosystem degradation can be constrained and reversed in the northwest arid region. 展开更多
关键词 Arid region Ecosystem services value ASSESSMENT Hotan Oasis
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Impacts of Land Use Change on Ecosystem Service Value in Yanchi County of Ningxia 被引量:3
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作者 杨越 孙保平 +3 位作者 哈斯 杜会石 赵岩 赵瑞 《Agricultural Science & Technology》 CAS 2013年第11期1687-1692,共6页
Based on TM image data in 1989, 1995, 1999, 2003, 2006 and 2009 of Yanchi County of Ningxia, the land use date of Yanchi County in each year were extracted supported by RS and GIS technology, and used to analyze the d... Based on TM image data in 1989, 1995, 1999, 2003, 2006 and 2009 of Yanchi County of Ningxia, the land use date of Yanchi County in each year were extracted supported by RS and GIS technology, and used to analyze the dynamic change of land use. The land use data were studied for estimating the change of ecosystem services value caused by the land use change of Yanchi County, using the evaluation method of China terrestrial ecosystem services value. The results showed that the changes of land use were obvious during 1989 to 2009. The area of woodland and construction land had an increasing tendency; grassland area changed from decreasing to increasing, which was in contrary to farmland and un-used land areas (from increasing to decreasing); water area fluctuated slightly. The ecosystem services value of Yanchi County had an increasing tendency during 1989 to 1995, because the increasing woodland area had took the major role in raising the total ecosystem services value. The grassland accounted for a large proportion of the total ecosystem service value of Yanchi County, with its contribution rate from 49.8% to 60.4%. And the composition of the ecosystem services value of Yanchi County happened benign change for the increasing contribution rate of woodland. The ecosystem services value sensitivity index of each land use type was less than 1, indicating that the ecosystem services value of Yanchi County lacks flexibility on its service value index, and the research results are reliable. 展开更多
关键词 Ecosystem services value Land use change Yanchi County of Ningxia
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Changes in Grassland Ecosystem Service Values in the Three-River Headwaters Region,China 被引量:3
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作者 赖敏 吴绍洪 +1 位作者 尹云鹤 潘韬 《Agricultural Science & Technology》 CAS 2013年第4期654-660,共7页
[Method] This study aimed to assess the changes in grassland ecosystem Service values in the Three-River Headwaters Region of China, the source of the Yangtze, Yellow (Huang He) and Lantsang (Mekong) rivers. [Meth... [Method] This study aimed to assess the changes in grassland ecosystem Service values in the Three-River Headwaters Region of China, the source of the Yangtze, Yellow (Huang He) and Lantsang (Mekong) rivers. [Method] Biophysical values of four services were monetized within the region, including water regulation, air quality regulation, climate regulation and soil conservation. [Result] The total ESVs were 884.97×10^8 Yuan, 1 302.06×10^8 Yuan and 1 299.49×10^8 Yuan in 2000, 2005 and 2008, respectively. The amount of value per unit area experienced a steep increase from 2000 to 2005(18.10×10^4 Yuan/km2), and then remained almost unchanged from 2005 to 2008 (-0.31×10^4 Yuan/km2). The ESV tended to decline from the southeastern to the northwestern. ESV in the eastern and central part increased faster than that in the south-central and western part of the TRHR from 2000 to 2008. It could be seen that the ecosystem condition of grassland in the TRHR improved signifi- cantly over the study period of 2000-2008. [Conelusion] The results provided good information to assess the effectiveness of current ecological protection measures in the TRHR and support regional sustainable management policies. 展开更多
关键词 Grassland ecosystem Ecosystem service value (ESV) VALUATION The Three-River Headwaters Region (TRHR)
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Water Quality Evaluation Index System for Freshwater Aquaculture Pond 被引量:5
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作者 刘曼红 于洪贤 +1 位作者 刘其根 王瑞梅 《Agricultural Science & Technology》 CAS 2011年第7期1025-1028,1038,共5页
[Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of fact... [Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of factors influencing water quality of freshwater aquaculture pond,and the importance degree of 14 factors influencing water quality of freshwater aquaculture pond was ordered.Then,five factors were selected as index to establish the water quality evaluation index system of freshwater aquaculture with the determination for thresholds of these factors.[Result] The importance degree of water quality of freshwater aquaculture pond showed an order of Dissolved oxygenpHPhytoplankton biomassSecchi depthTotal NitrogenZooplankton biomassWater temperatureBiochemical Oxygen DemandWater colorSalinityTotal hardness;according to the value of importance degree,the dissolved oxygen,pH,secchi depth,phytoplankton biomass and total nitrogen these five factors were selected as the index system of water quality evaluation of pond.The level of water quality of freshwater aquaculture pond was divided into five,and the tolerance range of fish to each index was obtained by expert observation.[Conclusion] This study had provided a scientific basis for water quality evaluation system of freshwater aquaculture pond. 展开更多
关键词 Freshwater aquaculture Water quality assessment Indexes system
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Response of Ecosystem Service Value Based on Land Use Changes and Analysis of its Driving Factors in Typical Hilly Region with Red Soil 被引量:6
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作者 邹金浪 王金政 +1 位作者 王鹏 乐文年 《Agricultural Science & Technology》 CAS 2010年第11期150-154,共5页
The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation w... The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation was employed to explore the contribution level of the indicators such as total population,urbanization level,proportion of primary industry and investment of social fixed assets on ecosystem service value,and the correlation analysis was also carried out.The results showed that the ecosystem service value in Xingguo County during 1996-2005 mainly was woodland,and the decrease of woodland area was the major reason for the sustained reduction of ecosystem service value.With the further increase of market demand and the incentives of local government,the garden area rapidly increased during 2001-2005,and the influence degree of garden towards the changes of ecosystem service value was only second to woodland,ranking No.2.Four socio-economic indicators had different correlation degree with ecosystem service value during the different research periods.Total population,urbanization level and proportion of primary industry had high correlation degree with ecosystem service value,whereas the influence degree of various socio-economic indicators on ecosystem service value was equal with each other day by day.Urbanization level,investment of social fixed assets and total population had significant negative correlation with ecosystem service value,while the proportion of primary industry had positive correlation with ecosystem service value. 展开更多
关键词 Ecosystem service value Land use change Gray correlation analysis Driving factor Hilly region with red soil
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Selection of Third-party Logistics Provider for Agricultural Products Based on System Comprehensive Evaluation 被引量:4
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作者 隋博文 庄丽娟 《Agricultural Science & Technology》 CAS 2015年第8期1824-1827,共4页
Through the analysis on the meanings and features as well as the ad- vantages of the third-party logistics for agricultural products, the quantization index system for the selection of third-party logistics providers ... Through the analysis on the meanings and features as well as the ad- vantages of the third-party logistics for agricultural products, the quantization index system for the selection of third-party logistics providers for agricultural products was constructed based on the system comprehensive evaluation theory. Analytic hierar- chy process (AHP) was used to determine the weight of the index system of each level, and AHP and fuzzy comprehensive evaluation method were used to determine the selection steps for the third-party logistics providers for agricultural products. The method was proved to be scientific and reasonable through calculation examples. 展开更多
关键词 System comprehensive evaluation Agricultural products Third-party lo-gistics provider Index system
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Happiness Index-oriented Tourism Area Management 被引量:1
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作者 余子萍 《Journal of Landscape Research》 2010年第3期55-57,共3页
The establishment of happiness index evaluation system for tourism resorts is an effective approach to enhance the scientific development of resorts and the well-being of people. Through analyzing happiness indexes of... The establishment of happiness index evaluation system for tourism resorts is an effective approach to enhance the scientific development of resorts and the well-being of people. Through analyzing happiness indexes of population in tourism resorts, this study aims to provide references for the scientific development of resorts. 展开更多
关键词 RESORTS Happiness index Evaluation system HUMAN-CENTERED
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