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Catastrophe theory-based risk evaluation model for water and mud inrush and its application in karst tunnels 被引量:23
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作者 ZHU Jian-qun LI Tian-zheng 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1587-1598,共12页
This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the ... This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the dangerousness of this geological disaster.The losses that are caused by water and mud inrush are taken into consideration to account for its harmfulness.Then a risk evaluation model based on the dangerousness-harmfulness evaluation indicator system is constructed,which is more convincing in comparison with the traditional methods.The catastrophe theory is used to evaluate the risk level of water and mud inrush and it has great advantage in handling problems involving discontinuous catastrophe processes.To validate the proposed approach,the Qiyueshan tunnel of Yichang-Wanzhou Railway is taken as an example in which four target segments are evaluated using the risk evaluation model.Finally,the evaluation results are compared with the excavation data,which shows that the risk levels predicted by the proposed approach are in good agreements with that observed in engineering.In conclusion,the catastrophe theory-based risk evaluation model is an efficient and effective approach for water and mud inrush in karst tunnels. 展开更多
关键词 risk evaluation model water and mud inrush catastrophe theory karst area TUNNELING
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A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value 被引量:5
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作者 徐润生 张建良 +3 位作者 左海滨 李克江 宋腾飞 邵久刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3990-3998,共9页
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific... The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal. 展开更多
关键词 blast furnace pulverized coal injection effective calorific value cost performance evaluation model
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Relative Efficiency Evaluation on Water Resource Utilization 被引量:3
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作者 MA Ying 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期60-64,共5页
Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM (group eigenvalue method)-MAUE (multi-attribute utility theory) mod... Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM (group eigenvalue method)-MAUE (multi-attribute utility theory) model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA (Data Envelopment Analysis) or ANN (Artificial Neural Networks), the mode was more applicable in some cases where decision-makers had preference for certain indicators 展开更多
关键词 water resource allocation group eigenvalue method multi-attribute utility theory evaluation
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Spatial quality evaluation for drinking water based on GIS and ant colony clustering algorithm 被引量:4
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作者 侯景伟 米文宝 李陇堂 《Journal of Central South University》 SCIE EI CAS 2014年第3期1051-1057,共7页
To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used.... To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used. Drinking water samples from 29 wells in Zhenping County, China, were collected and analyzed. 35 parameters on water quality were selected, such as chloride concentration, sulphate concentration, total hardness, nitrate concentration, fluoride concentration, turbidity, pH, chromium concentration, COD, bacterium amount, total coliforms and color. The best spatial interpolation methods for the 35 parameters were found and selected from all types of interpolation methods in GIS environment according to the minimum cross-validation errors. The ACCA was improved through three strategies, namely mixed distance function, average similitude degree and probability conversion functions. Then, the ACCA was carried out to obtain different water quality grades in the GIS environment. In the end, the result from the ACCA was compared with those from the competitive Hopfield neural network(CHNN) to validate the feasibility and effectiveness of the ACCA according to three evaluation indexes, which are stochastic sampling method, pixel amount and convergence speed. It is shown that the spatial water quality grades obtained from the ACCA were more effective, accurate and intelligent than those obtained from the CHNN. 展开更多
关键词 geographical information system (GIS) ant colony clustering algorithm (ACCA) quality evaluation drinking water spatial analysis
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Applying PP Model Based on RAGA in Water Environment Quality Evaluation
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作者 PANFeng FUQiang +1 位作者 LIANGChuan LIUDong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第2期171-175,共5页
Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the... Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the model in the water environment quality evaluation. The writer takes the water quality evaluated indexes of each sample as projection direction and turns high dimension data into low dimension projection value. Thus, the writer achieves on evaluating the grade of water samples and its optimum order. Based on this, the writer overcomes the jamming of weights calculated on fuzzy synthesize judge and gray system valuation. The paper can provide a new thought for water environment quality evaluation and other falling high dimension and optimum issue. 展开更多
关键词 RAGA PP model water environment quality evaluation
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A novel experimental system for performance evaluation of water powered percussive rock drill
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作者 李夕兵 李志国 +1 位作者 周梓荣 刘希灵 《Journal of Central South University》 SCIE EI CAS 2011年第6期1902-1909,共8页
A set of water powered excavation test system was developed for the comprehensive performance testing and evaluation of water powered percussive rock drill indoors. The whole system contains hydraulic power section, e... A set of water powered excavation test system was developed for the comprehensive performance testing and evaluation of water powered percussive rock drill indoors. The whole system contains hydraulic power section, electronic control system, test and data acquisition system, and assistant devices, such as guideway and drilling bench. Parameters of the water powered percussive rock drill can be obtained by analyzing testing data, which contain impact energy, front and back cavity pressure, pressure and flow in each working part, drilling velocity, frequency and energy efficiency etc. The system is applied to test the self-designed water powered percussive rock drill SYYG65. The parameters of water powered percussive rock drill with impact pressure of about 8.9 MPa are 58.93 J for impact energy, and 8.97% for energy efficiency, which prove the effectiveness of system. 展开更多
关键词 water powered percussive rock drill performance test water powered excavation comprehensive evaluation
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Applying Fuzzy Matter-Element Model Based on AHP to Evaluating Bids of Water Saving Irrigation Project 被引量:4
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作者 PANFeng FUQiang +1 位作者 LIANGChuan LIUDong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期147-151,共5页
Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is base... Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is based on the matter-element analysis and combined with the concepts of fuzzy mathematics,which is called the method of fuzzy matter-element analysis.It constructs the compound fuzzy matter element with the investment projects,evaluation factors and their fuzzy value.Through establishing the best subjection degree (fuzzy value),complex fuzzy matter element of relational coefficient and weight aggregation of fuzzy matter-element model,the writer achieves on optimum order of the investment projects according to the calculated relational degree and finds the best project.In this paper,the calculation of weight adopts the analytical hierarchy process method(AHP).Through the actual example,it shows that the model is simple and its calculation is reliable.It is very significant for the engineering evaluated bid and investment decision. 展开更多
关键词 fuzzy matter element water saving irrigation evaluating bid AHP relational degree
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The Application of PPE Model Based on RAGA in Benefit Evaluating of Rice Water Saving 被引量:3
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作者 FU Qiang,YANG Guang-lin,FU Hong(Northeast Agricultural University,Harbin,Heilongjiang,150030,PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期141-146,共6页
Through applying PPE model based on RAGA to evaluate the benefit of rice water saving,the author turns multi-dimension data into low dimension space.So the optimum projection direction can stand for the best influence... Through applying PPE model based on RAGA to evaluate the benefit of rice water saving,the author turns multi-dimension data into low dimension space.So the optimum projection direction can stand for the best influence on the collectivity.Thus,the value of projection function can evaluate each item good or not.The PPE model can avoid jamming of weight matrix in the method of fuzzy synthesize judgement,and obtain better result.The author wants to provide a new method and thought for readers who are engaged in investment decision-making of water saving irrigation and other relative study. 展开更多
关键词 RAGA PPE benefit of water saving irrigation evaluation
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Evaluation on Environment State of Breeding Area in Shuidong Bay by Using Fuzzy Comprehensive Evaluation Method 被引量:1
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作者 XU Yonghua 1,and SUN Yong 2 1 Heilongjiang Agriculture Polytechnic University,Jiamusi 154007,Heilongjiang,China 2 Engineering College,Northeast Agricultural University,Harbin 150030,China 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第2期64-68,共5页
Fuzzy comprehensive evaluation method was used to develop a standard model to analyze and evaluate nearness degree of water environment quality at breeding area of Shuidong Bay in China.Results showed that certain env... Fuzzy comprehensive evaluation method was used to develop a standard model to analyze and evaluate nearness degree of water environment quality at breeding area of Shuidong Bay in China.Results showed that certain environment contamination factors in some areas seriously exceeded the standard value and led to the whole water quality at the third class level.The measurements should be taken to promote the sustainable development of breeding area in Shuidong Bay. 展开更多
关键词 fuzzy comprehensive evaluation method nearness degree water environment quality
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Importance of “connectedness” between herds for effective across herd genetic evaluation
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作者 P. K. MATHUR (Canadian Center for Swine Improvement, Central Experimental Farm, Building 54, Maple Drive, Ottawa, ON, K1A 0C6, Canada) 《华南农业大学学报》 CAS CSCD 北大核心 2005年第S1期61-68,共8页
“Connectedness” is an essential component of genetic evaluations. The degree of connectedness affects the accuracy of comparing estimated breeding values (EBVs) from one herd or contemporary group to the other. It c... “Connectedness” is an essential component of genetic evaluations. The degree of connectedness affects the accuracy of comparing estimated breeding values (EBVs) from one herd or contemporary group to the other. It can be measured through Connectedness Rating (CR) which is based on variances and covariance among the estimates of contemporary group effects. A computing algorithm and a computer program for estimating CR is available. The minimum required level of connectedness depends upon the size of the contemporary groups, the level of accuracy and the residual variance. About 48% CR is required to detect differences between EBVs that are greater than 20% of the standard deviation in the trait, for group sizes of about 100 animals. Higher levels are necessary for smaller group sizes and for more accurate comparisons. Breeders participating in a common genetic evaluation program should therefore exchange their superior genetics and possibly use some common testing facilities for meaningful estimates of breeding values. Maintaining a good connectedness level will make the genetic evaluation program more useful for selection of superior breeding animals and achieving faster rate of genetic progress. 展开更多
关键词 connectedness breeding values genetic evaluation
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A Method for Accuracy of Genetic Evaluation by Utilization of Canadian Genetic Evaluation Information to Improve Heilongjiang Holstein Herds
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作者 DINGKe-wei TAKEOKayaba 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期23-29,共7页
The objectives of this study were to set up a new genetic evaluation procedure to predict the breeding values of Holstein herds in Heilongjiang Province of China for milk and fat production by utilizing Canadian pedig... The objectives of this study were to set up a new genetic evaluation procedure to predict the breeding values of Holstein herds in Heilongjiang Province of China for milk and fat production by utilizing Canadian pedigree and genetic evaluation information and to compare the breeding values of the sires from different countries. The data used for evaluating young sires for the Chinese Holstein population consisted of records selected from 21 herds in Heilongjiang Province. The first lactation records of 2 496 daughters collected in 1989 and 2000 were analyzed. A single-trait animal model including a fixed herd-year effect, random animal and residual effects was used by utilizing Canadian pedigree and genetic evaluation information of 5 126 sires released from the Canadian Dairy Network in August 2000. The BLUP procedure was used to evaluate all cattle in this study and the Estimated Breeding Values (EBV)for milk and fat production of 6 697 cattle (including 673 sires and 6 024 cows) were predicted. The genetic levels of the top 100 sires originated from different countries were compared. Unlike the BLUP procedure that is being used in conjunction with the single-trait sire model in Heilongjiang Province of China now, the genetic evaluation procedure used in this study not only can be used simultaneously to evaluate sires and cows but also increase the accuracy of evaluation due to using the relationships and genetic values of the Canadian evaluated sires with more daughters. The results showed that the new procedure was useful for genetic evaluation of dairy herds and the comparison of the breeding values of these sires imported from different countries showed that a significant genetic improvement has been achieved for milk production of the Heilongjiang Holstein dairy population by importing sires from foreign countries, especially from the United States due to the higher breeding values. 展开更多
关键词 MILK FAT Heilongjiang Chinese Holsteins genetic evaluations breeding values
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新时代职业院校学生发展评价体系构建——基于成长增值和画像视角 被引量:5
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作者 黄贤智 王彬谕 +1 位作者 盘霞 黄君 《职业技术教育》 北大核心 2025年第2期74-79,共6页
深化职业教育评价改革的重要内涵之一是提高技术技能人才培养质量,也是职业教育高质量发展的重要抓手。针对当前职业院校学生发展评价中存在的评价指标缺乏“精准性”、评价特征缺乏“职教性”、评价方法缺乏“过程性”、评价机制缺乏... 深化职业教育评价改革的重要内涵之一是提高技术技能人才培养质量,也是职业教育高质量发展的重要抓手。针对当前职业院校学生发展评价中存在的评价指标缺乏“精准性”、评价特征缺乏“职教性”、评价方法缺乏“过程性”、评价机制缺乏“全面性”等问题,结合新时代职业教育技术技能人才个性化、多元化特点,充分利用学校多平台学生基础数据,坚持强化过程评价、改进结果评价、探索增值评价,基于学生成长增值和画像的视角,构建了职业院校学生评价体系。在运用该评价指标体系时,需要建立人才发展评价程序形成基础数据库、运用人才发展增值评价强化过程监控、绘制人才发展全息画像激发学生发展意识、形成人才发展数据简历匹配用人需求。 展开更多
关键词 职业教育 增值评价 学生画像 人才评价 数字化转型 就业质量
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陕北白绒山羊几种非常规饲料营养成分、体外发酵参数和酶活性研究 被引量:3
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作者 李陇平 吴仪 +5 位作者 王旭辉 杜媛媛 曹萌霜 李托 屈雷 李强 《动物营养学报》 北大核心 2025年第1期603-616,共14页
本试验旨在通过研究几种非常规饲料营养成分、体外发酵参数和酶活性,筛选适宜陕北白绒山羊高效利用的非常规饲料资源。试验测定柳枝稷、菊芋秸秆、葵花头、沙打旺、马铃薯秧、花生秧、羊草和玉米秸秆的常规营养成分、相对饲用价值(RFV)... 本试验旨在通过研究几种非常规饲料营养成分、体外发酵参数和酶活性,筛选适宜陕北白绒山羊高效利用的非常规饲料资源。试验测定柳枝稷、菊芋秸秆、葵花头、沙打旺、马铃薯秧、花生秧、羊草和玉米秸秆的常规营养成分、相对饲用价值(RFV)和有效能值,结合体外发酵产气试验,测定产气量、甲烷产量、发酵参数和发酵液酶活性等指标,进行综合营养价值评价。结果表明:1)葵花头和沙打旺粗蛋白质(CP)含量极显著高于其他6种饲料(P<0.01),菊芋秸秆和马铃薯秧粗灰分(Ash)和钙含量极显著高于其他6种饲料(P<0.01),羊草中性洗涤纤维(NDF)(玉米秸秆除外)和酸性洗涤纤维(ADF)含量极显著高于其他7种饲料(P<0.01)。2)菊芋秸秆干物质采食量(DMI)极显著高于其他7种饲料(P<0.01),葵花头总可消化养分(TDN)含量以及RFV和相对牧草品质(RFQ)最高,羊草DMI(玉米秸秆除外)、TDN含量以及RFV和RFQ极显著低于其他7种饲料(P<0.01)。3)葵花头和沙打旺消化能(DE)、代谢能(ME)和增重净能(NEg)极显著高于其他6种饲料(P<0.01)。4)各种饲料72 h发酵累积产气量由高到低依次为葵花头>菊芋秸秆>沙打旺>柳枝稷>玉米秸秆>羊草>花生秧>马铃薯秧,花生秧和马铃薯秧甲烷产量极显著高于其他6种饲料(P<0.01)。5)菊芋秸秆发酵液pH极显著高于其他7种饲料(P<0.01);菊芋秸秆、马铃薯秧和葵花头发酵液氨态氮(NH 3-N)含量极显著高于其他5种饲料(P<0.01);花生秧、马铃薯秧和葵花头发酵液微生物蛋白(MCP)含量较高;花生秧、葵花头和菊芋秸秆发酵液乙酸含量较高;柳枝稷发酵液乙酸/丙酸值最低;葵花头发酵液总挥发性性脂肪酸含量最高。6)花生秧发酵液α-淀粉酶、葵花头发酵液胰蛋白酶、沙打旺发酵液纤维素酶以及菊芋秸秆发酵液果胶酶活性均分别显著高于其他7种饲料(P<0.05),柳枝稷、羊草、玉米秸秆和花生秧发酵液脂肪酶活性极显著高于其他4种饲料(P<0.01)。综上所述,葵花头、菊芋秸秆和沙打旺在陕北白绒山羊养殖中具有较高的利用价值。 展开更多
关键词 陕北白绒山羊 非常规饲料 营养价值 评价
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2025中国茶叶区域公用品牌价值评估报告 被引量:9
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作者 胡晓云 魏春丽 单子昊 《中国茶叶》 2025年第5期30-42,共13页
2024年底至2025年4月,由4个相关单位组成的课题组以“中国农产品区域公用品牌价值评估模型”(简称CARD模型)为理论工具,延续2010年至今的“中国茶叶区域公用品牌价值评估研究”专项课题,开展了多方调研,并结合数字化信息技术,对2022—2... 2024年底至2025年4月,由4个相关单位组成的课题组以“中国农产品区域公用品牌价值评估模型”(简称CARD模型)为理论工具,延续2010年至今的“中国茶叶区域公用品牌价值评估研究”专项课题,开展了多方调研,并结合数字化信息技术,对2022—2024年3年间的相关数据进行分析、评估,得出2025年中国茶叶区域公用品牌价值的评估结论。文章以评估数据为基础,结合近年来中国茶产业、茶品牌发展的相关数据与资料,综合分析了中国茶品牌建设的现象与问题,并对中国茶品牌的未来发展提出了4条针对性建议。 展开更多
关键词 茶叶 区域公用品牌 品牌价值 价值评估
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西藏雅尼湿地水质评价及污染源分析 被引量:1
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作者 李伟 杨崛园 +3 位作者 熊健 黄瑞卿 杨博 吕学斌 《水生态学杂志》 北大核心 2025年第4期119-131,共13页
评价雅尼湿地水质状况,解析水体的污染来源,为雅尼湿地环境监测与保护提供科学依据。基于雅尼湿地流域平水期58个样品的9项理化指标,运用综合营养状态指数法(TLI)、综合污染指数法和综合水质指数法(WQI)对目标水体水质状况和富营养化水... 评价雅尼湿地水质状况,解析水体的污染来源,为雅尼湿地环境监测与保护提供科学依据。基于雅尼湿地流域平水期58个样品的9项理化指标,运用综合营养状态指数法(TLI)、综合污染指数法和综合水质指数法(WQI)对目标水体水质状况和富营养化水平进行评估,采用主成分分析法(PCA)和绝对主成分-多元线性回归(APCS-MLR)模型对雅尼湿地水质特征及污染来源进行分析。结果表明:(1)雅尼湿地总磷(TP)、氨氮(NH_(3)-N)和化学需氧量(COD)指标均达到《地表水环境质量标准》Ⅰ类水质标准,总氮(TN)达到Ⅱ类水质标准,湿地整体水质良好;湿地TLI为36.88,为中营养状态;综合污染指数为0.74,表现为轻污染,TN和TP值的污染分担率高于60%,是湿地水体主要的污染因子;WQI总体处于“良好”水平;(2)PCA结果显示,前4项因子的累计贡献率为82.497%,第1主成分(PC1)推测为自然源,第2主成分(PC2)推测为农业-生活源,第3主成分(PC3)推测为畜禽养殖-农业源,第4主成分(PC4)推测为藻类暴发源;根据主成分/综合主成分得分分析雅尼湿地水质空间变化总体呈上游优于中下游的特征;(3)APCS-MLR模型结果显示,自然源对雅尼湿地水质影响的贡献率为31.64%,未知源贡献率为30.47%,畜禽养殖-农业混合源贡献率为23.30%。TN、TP和NH_(3)-N的主要来源为农村化肥施用、牲畜集聚排泄。 展开更多
关键词 雅尼湿地 水质评价 污染源解析 西藏
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低渗透砂岩储层解水锁剂优选及效果评价——以鄂尔多斯盆地X气田为例 被引量:2
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作者 蒲万芬 侯帅 +4 位作者 沈超 杜代军 刘锐 郭健 徐东晓 《大庆石油地质与开发》 北大核心 2025年第2期50-57,共8页
为解决低渗透砂岩气藏特别是存在边底水的气藏在勘探开发过程中容易产生严重水锁现象的问题,利用表面张力测试、接触角实验、气驱液岩心驱替实验以及核磁共振技术等多种方法,从解水锁剂的优选和解水锁效果评价2方面进行了深入研究。结... 为解决低渗透砂岩气藏特别是存在边底水的气藏在勘探开发过程中容易产生严重水锁现象的问题,利用表面张力测试、接触角实验、气驱液岩心驱替实验以及核磁共振技术等多种方法,从解水锁剂的优选和解水锁效果评价2方面进行了深入研究。结果表明:在约3倍模拟地层水矿化度条件下,以及在渗透率大于等于2.0×10^(-3)µm^(2)的岩心中,优选的0.3%(质量分数)配2+模拟地层水的解水锁剂体系仍表现出良好的降低水锁损害的效果;利用核磁共振T2谱测试实验和核磁成像技术对比单一模拟地层水与加入解水锁剂后的驱替效果,结果显示驱替结束后对应的峰面积相较于未加解水锁剂的峰面积明显减小,充分证实了优选的解水锁剂体系在降低水锁损害方面的良好效果。研究成果提供了一种有效优选及评价解水锁剂的方法,有助于最大程度地发挥优选的解水锁剂体系的解水锁效果。 展开更多
关键词 低渗透 边底水气藏 水锁 解水锁剂 效果评价 核磁共振 鄂尔多斯盆地
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中国农业农村现代化的发展水平测度与障碍因子识别 被引量:7
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作者 王勇 李明颢 《统计与信息论坛》 北大核心 2025年第3期14-29,共16页
农业农村现代化是当前社会主义现代化建设的重大任务。在这一背景下,把握农业农村现代化进度、弥补农业农村现代化短板具有重要意义。首先构建农业农村现代化评价指标体系并确定2035年目标值,在此基础上,以2011—2021年为研究区间,运用... 农业农村现代化是当前社会主义现代化建设的重大任务。在这一背景下,把握农业农村现代化进度、弥补农业农村现代化短板具有重要意义。首先构建农业农村现代化评价指标体系并确定2035年目标值,在此基础上,以2011—2021年为研究区间,运用线性加权综合模型及障碍度模型,从全国、区域及省域三个层面分析中国农业农村现代化发展水平并识别主要障碍因子。研究结果表明,在发展水平方面:首先,全国农业农村现代化发展水平持续提升,农业现代化水平高于农村现代化水平,但发展速度慢于后者;其次,东部地区农业农村现代化水平始终较高,已进入转型跨越阶段,四大经济区域在各子系统层与准则层间存在发展水平与发展速度差异;最后,省域间农业农村现代化水平差距较大,11省份农业农村现代化处于发展阶段,16省份农业农村现代化进入提升阶段,江苏、天津、上海、北京四地农业农村现代化已进入转型跨越阶段。在障碍因子方面:首先,农业保险深度、农村燃气普及率、农村生活污水处理率及村庄绿地率始终是全国农业农村现代化发展的主要障碍,2021年,农产品加工业产值与农业总产值之比替代农村生活污水处理率成为阻碍全国农业农村现代化推进的最大障碍;其次,农业保险深度、村庄绿地率及农产品加工业产值与农业总产值之比是各区域农业农村现代化发展的共同主要障碍,东部地区主要障碍因子逐渐向农业现代化子系统内部转移,东北、中部及西部地区则与全国层面障碍因子情况较为一致;最后,在障碍度大于等于5%的指标中,农业保险深度、农村燃气普及率、农村居民人均生活用电量、农村生活污水处理率、村庄绿地率及农产品加工业产值与农业总产值之比六项指标对各省份农业农村现代化发展具有普遍制约作用。本文对明确农业农村现代化进程与短板、分层面制定农业农村现代化规划具有借鉴意义。 展开更多
关键词 农业农村现代化 目标值 指标体系 发展水平 障碍因子
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江西省首单水土保持生态产品交易价值核算主要做法及探讨 被引量:2
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作者 李智广 涂安国 +4 位作者 于来会 盛菲 肖胜生 王海燕 郑海金 《中国水土保持》 2025年第1期24-28,31,I0005,共7页
2024年12月10日,江西省上饶市广丰区祝家坞马家柚基地水土保持生态产品交易在南昌签约成交,这是江西省推动水土保持生态产品价值实现的第一单交易,是贯彻落实《关于建立健全生态清洁小流域水土保持生态产品价值实现机制的意见》在全国... 2024年12月10日,江西省上饶市广丰区祝家坞马家柚基地水土保持生态产品交易在南昌签约成交,这是江西省推动水土保持生态产品价值实现的第一单交易,是贯彻落实《关于建立健全生态清洁小流域水土保持生态产品价值实现机制的意见》在全国的率先突破,对进一步拓宽“两山”转化的水土保持新路径、推动“两山”理念指导发展水土保持新质生产力提供了实践案例。以本次交易为例,阐述了水土保持生态产品价值核算的主要做法:①研究确定生态产品价值核算基本原则与技术路线;②全面查清项目区概况及水土保持措施现状;③依规研判确定生态产品价值核算指标;④调查研判生态产品功能量与其单价;⑤核算生态产品价值量。为增加生态产品价值核算的科学性和可靠性,提升生态产品价值市场化实现程度,在下一步工作中应注意坚持合规性、客观性、可比性的原则,全面调研掌握项目实际情况,分析和确定生态产品类型及其价值核算的指标与功能量、单价,保证核算所得价值量科学、合理。 展开更多
关键词 水土保持 生态产品 价值核算 “两山”转化 江西省
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劳动价值论视角下生态产品价值实现机制的系统构建 被引量:3
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作者 贺超 蒋雯文 崔权雪 《价格月刊》 北大核心 2025年第2期1-8,共8页
生态产品价值实现与“两山”理念一脉相承,是对马克思劳动价值论的丰富和发展,体现了党和国家推进生态文明建设的坚定决心。现有的生态产品内涵尚未形成科学共识,理论研究滞后实践的困境尤为突出。通过剖析生态产品价值构成,厘清了建构... 生态产品价值实现与“两山”理念一脉相承,是对马克思劳动价值论的丰富和发展,体现了党和国家推进生态文明建设的坚定决心。现有的生态产品内涵尚未形成科学共识,理论研究滞后实践的困境尤为突出。通过剖析生态产品价值构成,厘清了建构生态产品价值实现机制的内在逻辑;从排他性、非竞争性等属性出发,提出了以明晰产权建构生态产品价值实现机制的实践优化方向;讨论了设置、界定产权和维护产权的交易成本约束问题。基于研究结论,提出了以生态产品价值实现统筹国土、自然资源资产登记确权工作,创新以价值实现为导向的生态产品产权体系,强化技术支撑,降低产权路径交易成本,进一步聚焦纯公共资源类生态产品的保护,引导推动生态产业化来强化产权路径的效果等对策建议。 展开更多
关键词 生态产品 价值实现机制 劳动价值论 “两山”理念 产权
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50份黄淮产区大豆种质资源苗期耐盐性评价 被引量:1
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作者 徐宗昌 鲁雪莉 +6 位作者 姜奇彦 宋奕汝 王晓宇 曲迎玉 张成省 李义强 王萌 《中国油料作物学报》 北大核心 2025年第4期851-860,共10页
为减少我国大豆对外依存度,筛选耐盐碱品种,对主要来自黄淮夏大豆产区的50份大豆种质进行盐胁迫处理,即苗期1.6%浓度的NaCl处理,调查盐害指数、测定苗期株高、根长、地上生物量干/鲜重、根干/鲜重、倒二叶面积、主根粗和主茎粗等农艺指... 为减少我国大豆对外依存度,筛选耐盐碱品种,对主要来自黄淮夏大豆产区的50份大豆种质进行盐胁迫处理,即苗期1.6%浓度的NaCl处理,调查盐害指数、测定苗期株高、根长、地上生物量干/鲜重、根干/鲜重、倒二叶面积、主根粗和主茎粗等农艺指标,对大豆种质资源进行苗期耐盐评价与筛选。结果表明:盐胁迫下大豆苗期农艺性状指标变化丰富,变异系数为17.14%~35.16%。通过盐害指数评价方法鉴定到高耐盐材料2份、耐盐材料29份;采用D值综合评价方法鉴定到耐盐材料9份。两种评价中均为耐盐材料的有华育6号、临选3号、临豆21、齐黄39、冀豆12、徐豆18以及临选2号等7个。对盐害指数评价和D值综合评价下的大豆耐盐能力排名进行关联分析,发现两种评价方式对大豆耐盐性排名具有极显著正相关性,同时,D值综合评价方法耐盐阈值更高,较盐害指数评价法或更为可靠,可为高通量筛选大豆耐盐品种提供依据。 展开更多
关键词 大豆 盐胁迫 盐害指数 D值综合评价 耐盐种质资源
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